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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * EMIF driver
   4 *
   5 * Copyright (C) 2012 Texas Instruments, Inc.
   6 *
   7 * Aneesh V <aneesh@ti.com>
   8 * Santosh Shilimkar <santosh.shilimkar@ti.com>
 
 
 
 
   9 */
  10#include <linux/err.h>
  11#include <linux/kernel.h>
  12#include <linux/reboot.h>
  13#include <linux/platform_data/emif_plat.h>
  14#include <linux/io.h>
  15#include <linux/device.h>
  16#include <linux/platform_device.h>
  17#include <linux/interrupt.h>
  18#include <linux/slab.h>
  19#include <linux/of.h>
  20#include <linux/debugfs.h>
  21#include <linux/seq_file.h>
  22#include <linux/module.h>
  23#include <linux/list.h>
  24#include <linux/spinlock.h>
  25#include <linux/pm.h>
  26
  27#include "emif.h"
  28#include "jedec_ddr.h"
  29#include "of_memory.h"
  30
  31/**
  32 * struct emif_data - Per device static data for driver's use
  33 * @duplicate:			Whether the DDR devices attached to this EMIF
  34 *				instance are exactly same as that on EMIF1. In
  35 *				this case we can save some memory and processing
  36 * @temperature_level:		Maximum temperature of LPDDR2 devices attached
  37 *				to this EMIF - read from MR4 register. If there
  38 *				are two devices attached to this EMIF, this
  39 *				value is the maximum of the two temperature
  40 *				levels.
  41 * @node:			node in the device list
  42 * @base:			base address of memory-mapped IO registers.
  43 * @dev:			device pointer.
 
  44 * @regs_cache:			An array of 'struct emif_regs' that stores
  45 *				calculated register values for different
  46 *				frequencies, to avoid re-calculating them on
  47 *				each DVFS transition.
  48 * @curr_regs:			The set of register values used in the last
  49 *				frequency change (i.e. corresponding to the
  50 *				frequency in effect at the moment)
  51 * @plat_data:			Pointer to saved platform data.
  52 * @debugfs_root:		dentry to the root folder for EMIF in debugfs
  53 * @np_ddr:			Pointer to ddr device tree node
  54 */
  55struct emif_data {
  56	u8				duplicate;
  57	u8				temperature_level;
  58	u8				lpmode;
  59	struct list_head		node;
  60	unsigned long			irq_state;
  61	void __iomem			*base;
  62	struct device			*dev;
 
  63	struct emif_regs		*regs_cache[EMIF_MAX_NUM_FREQUENCIES];
  64	struct emif_regs		*curr_regs;
  65	struct emif_platform_data	*plat_data;
  66	struct dentry			*debugfs_root;
  67	struct device_node		*np_ddr;
  68};
  69
  70static struct emif_data *emif1;
  71static DEFINE_SPINLOCK(emif_lock);
  72static unsigned long	irq_state;
 
  73static LIST_HEAD(device_list);
  74
  75#ifdef CONFIG_DEBUG_FS
  76static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
  77	struct emif_regs *regs)
  78{
  79	u32 type = emif->plat_data->device_info->type;
  80	u32 ip_rev = emif->plat_data->ip_rev;
  81
  82	seq_printf(s, "EMIF register cache dump for %dMHz\n",
  83		regs->freq/1000000);
  84
  85	seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
  86	seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
  87	seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
  88	seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
  89
  90	if (ip_rev == EMIF_4D) {
  91		seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
  92			regs->read_idle_ctrl_shdw_normal);
  93		seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
  94			regs->read_idle_ctrl_shdw_volt_ramp);
  95	} else if (ip_rev == EMIF_4D5) {
  96		seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
  97			regs->dll_calib_ctrl_shdw_normal);
  98		seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
  99			regs->dll_calib_ctrl_shdw_volt_ramp);
 100	}
 101
 102	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
 103		seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
 104			regs->ref_ctrl_shdw_derated);
 105		seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
 106			regs->sdram_tim1_shdw_derated);
 107		seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
 108			regs->sdram_tim3_shdw_derated);
 109	}
 110}
 111
 112static int emif_regdump_show(struct seq_file *s, void *unused)
 113{
 114	struct emif_data	*emif	= s->private;
 115	struct emif_regs	**regs_cache;
 116	int			i;
 117
 118	if (emif->duplicate)
 119		regs_cache = emif1->regs_cache;
 120	else
 121		regs_cache = emif->regs_cache;
 122
 123	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
 124		do_emif_regdump_show(s, emif, regs_cache[i]);
 125		seq_putc(s, '\n');
 126	}
 127
 128	return 0;
 129}
 130
 131DEFINE_SHOW_ATTRIBUTE(emif_regdump);
 
 
 
 
 
 
 
 
 
 132
 133static int emif_mr4_show(struct seq_file *s, void *unused)
 134{
 135	struct emif_data *emif = s->private;
 136
 137	seq_printf(s, "MR4=%d\n", emif->temperature_level);
 138	return 0;
 139}
 140
 141DEFINE_SHOW_ATTRIBUTE(emif_mr4);
 
 
 
 
 
 
 
 
 
 142
 143static int __init_or_module emif_debugfs_init(struct emif_data *emif)
 144{
 145	emif->debugfs_root = debugfs_create_dir(dev_name(emif->dev), NULL);
 146	debugfs_create_file("regcache_dump", S_IRUGO, emif->debugfs_root, emif,
 147			    &emif_regdump_fops);
 148	debugfs_create_file("mr4", S_IRUGO, emif->debugfs_root, emif,
 149			    &emif_mr4_fops);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 150	return 0;
 
 
 
 
 151}
 152
 153static void __exit emif_debugfs_exit(struct emif_data *emif)
 154{
 155	debugfs_remove_recursive(emif->debugfs_root);
 156	emif->debugfs_root = NULL;
 157}
 158#else
 159static inline int __init_or_module emif_debugfs_init(struct emif_data *emif)
 160{
 161	return 0;
 162}
 163
 164static inline void __exit emif_debugfs_exit(struct emif_data *emif)
 
 
 
 165{
 
 
 166}
 167#endif
 168
 169/*
 170 * Get bus width used by EMIF. Note that this may be different from the
 171 * bus width of the DDR devices used. For instance two 16-bit DDR devices
 172 * may be connected to a given CS of EMIF. In this case bus width as far
 173 * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
 174 */
 175static u32 get_emif_bus_width(struct emif_data *emif)
 176{
 177	u32		width;
 178	void __iomem	*base = emif->base;
 179
 180	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
 181			>> NARROW_MODE_SHIFT;
 182	width = width == 0 ? 32 : 16;
 183
 184	return width;
 185}
 186
 
 
 
 
 
 
 
 
 
 
 
 
 
 187static void set_lpmode(struct emif_data *emif, u8 lpmode)
 188{
 189	u32 temp;
 190	void __iomem *base = emif->base;
 191
 192	/*
 193	 * Workaround for errata i743 - LPDDR2 Power-Down State is Not
 194	 * Efficient
 195	 *
 196	 * i743 DESCRIPTION:
 197	 * The EMIF supports power-down state for low power. The EMIF
 198	 * automatically puts the SDRAM into power-down after the memory is
 199	 * not accessed for a defined number of cycles and the
 200	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
 201	 * As the EMIF supports automatic output impedance calibration, a ZQ
 202	 * calibration long command is issued every time it exits active
 203	 * power-down and precharge power-down modes. The EMIF waits and
 204	 * blocks any other command during this calibration.
 205	 * The EMIF does not allow selective disabling of ZQ calibration upon
 206	 * exit of power-down mode. Due to very short periods of power-down
 207	 * cycles, ZQ calibration overhead creates bandwidth issues and
 208	 * increases overall system power consumption. On the other hand,
 209	 * issuing ZQ calibration long commands when exiting self-refresh is
 210	 * still required.
 211	 *
 212	 * WORKAROUND
 213	 * Because there is no power consumption benefit of the power-down due
 214	 * to the calibration and there is a performance risk, the guideline
 215	 * is to not allow power-down state and, therefore, to not have set
 216	 * the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
 217	 */
 218	if ((emif->plat_data->ip_rev == EMIF_4D) &&
 219	    (lpmode == EMIF_LP_MODE_PWR_DN)) {
 220		WARN_ONCE(1,
 221			  "REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
 222		/* rollback LP_MODE to Self-refresh mode */
 223		lpmode = EMIF_LP_MODE_SELF_REFRESH;
 224	}
 225
 226	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
 227	temp &= ~LP_MODE_MASK;
 228	temp |= (lpmode << LP_MODE_SHIFT);
 229	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
 230}
 231
 232static void do_freq_update(void)
 233{
 234	struct emif_data *emif;
 235
 236	/*
 237	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
 238	 *
 239	 * i728 DESCRIPTION:
 240	 * The EMIF automatically puts the SDRAM into self-refresh mode
 241	 * after the EMIF has not performed accesses during
 242	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
 243	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
 244	 * to 0x2. If during a small window the following three events
 245	 * occur:
 246	 * - The SR_TIMING counter expires
 247	 * - And frequency change is requested
 248	 * - And OCP access is requested
 249	 * Then it causes instable clock on the DDR interface.
 250	 *
 251	 * WORKAROUND
 252	 * To avoid the occurrence of the three events, the workaround
 253	 * is to disable the self-refresh when requesting a frequency
 254	 * change. Before requesting a frequency change the software must
 255	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
 256	 * frequency change has been done, the software can reprogram
 257	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
 258	 */
 259	list_for_each_entry(emif, &device_list, node) {
 260		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
 261			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
 262	}
 263
 264	/*
 265	 * TODO: Do FREQ_UPDATE here when an API
 266	 * is available for this as part of the new
 267	 * clock framework
 268	 */
 269
 270	list_for_each_entry(emif, &device_list, node) {
 271		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
 272			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
 273	}
 274}
 275
 276/* Find addressing table entry based on the device's type and density */
 277static const struct lpddr2_addressing *get_addressing_table(
 278	const struct ddr_device_info *device_info)
 279{
 280	u32		index, type, density;
 281
 282	type = device_info->type;
 283	density = device_info->density;
 284
 285	switch (type) {
 286	case DDR_TYPE_LPDDR2_S4:
 287		index = density - 1;
 288		break;
 289	case DDR_TYPE_LPDDR2_S2:
 290		switch (density) {
 291		case DDR_DENSITY_1Gb:
 292		case DDR_DENSITY_2Gb:
 293			index = density + 3;
 294			break;
 295		default:
 296			index = density - 1;
 297		}
 298		break;
 299	default:
 300		return NULL;
 301	}
 302
 303	return &lpddr2_jedec_addressing_table[index];
 304}
 305
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 306static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
 307		bool cs1_used, bool cal_resistors_per_cs)
 308{
 309	u32 zq = 0, val = 0;
 310
 311	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
 312	zq |= val << ZQ_REFINTERVAL_SHIFT;
 313
 314	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
 315	zq |= val << ZQ_ZQCL_MULT_SHIFT;
 316
 317	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
 318	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
 319
 320	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
 321
 322	if (cal_resistors_per_cs)
 323		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
 324	else
 325		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
 326
 327	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
 328
 329	val = cs1_used ? 1 : 0;
 330	zq |= val << ZQ_CS1EN_SHIFT;
 331
 332	return zq;
 333}
 334
 335static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
 336		const struct emif_custom_configs *custom_configs, bool cs1_used,
 337		u32 sdram_io_width, u32 emif_bus_width)
 338{
 339	u32 alert = 0, interval, devcnt;
 340
 341	if (custom_configs && (custom_configs->mask &
 342				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
 343		interval = custom_configs->temp_alert_poll_interval_ms;
 344	else
 345		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
 346
 347	interval *= 1000000;			/* Convert to ns */
 348	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
 349	alert |= (interval << TA_REFINTERVAL_SHIFT);
 350
 351	/*
 352	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
 353	 * also to this form and subtract to get TA_DEVCNT, which is
 354	 * in log2(x) form.
 355	 */
 356	emif_bus_width = __fls(emif_bus_width) - 1;
 357	devcnt = emif_bus_width - sdram_io_width;
 358	alert |= devcnt << TA_DEVCNT_SHIFT;
 359
 360	/* DEVWDT is in 'log2(x) - 3' form */
 361	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
 362
 363	alert |= 1 << TA_SFEXITEN_SHIFT;
 364	alert |= 1 << TA_CS0EN_SHIFT;
 365	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
 366
 367	return alert;
 368}
 369
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 370static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
 371{
 372	u32 pwr_mgmt_ctrl	= 0, timeout;
 373	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
 374	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
 375	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
 376	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
 377	u32 mask;
 378	u8 shift;
 379
 380	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
 381
 382	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
 383		lpmode		= cust_cfgs->lpmode;
 384		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
 385		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
 386		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
 387	}
 388
 389	/* Timeout based on DDR frequency */
 390	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
 391
 392	/*
 393	 * The value to be set in register is "log2(timeout) - 3"
 394	 * if timeout < 16 load 0 in register
 395	 * if timeout is not a power of 2, round to next highest power of 2
 396	 */
 397	if (timeout < 16) {
 398		timeout = 0;
 399	} else {
 400		if (timeout & (timeout - 1))
 401			timeout <<= 1;
 402		timeout = __fls(timeout) - 3;
 
 
 403	}
 404
 405	switch (lpmode) {
 406	case EMIF_LP_MODE_CLOCK_STOP:
 407		shift = CS_TIM_SHIFT;
 408		mask = CS_TIM_MASK;
 409		break;
 410	case EMIF_LP_MODE_SELF_REFRESH:
 411		/* Workaround for errata i735 */
 412		if (timeout < 6)
 413			timeout = 6;
 414
 415		shift = SR_TIM_SHIFT;
 416		mask = SR_TIM_MASK;
 417		break;
 418	case EMIF_LP_MODE_PWR_DN:
 419		shift = PD_TIM_SHIFT;
 420		mask = PD_TIM_MASK;
 421		break;
 422	case EMIF_LP_MODE_DISABLE:
 423	default:
 424		mask = 0;
 425		shift = 0;
 426		break;
 427	}
 428	/* Round to maximum in case of overflow, BUT warn! */
 429	if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
 430		pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
 431		       lpmode,
 432		       timeout_perf,
 433		       timeout_pwr,
 434		       freq_threshold);
 435		WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
 436		     timeout, mask >> shift);
 437		timeout = mask >> shift;
 438	}
 439
 440	/* Setup required timing */
 441	pwr_mgmt_ctrl = (timeout << shift) & mask;
 442	/* setup a default mask for rest of the modes */
 443	pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
 444			  ~mask;
 445
 446	/* No CS_TIM in EMIF_4D5 */
 447	if (ip_rev == EMIF_4D5)
 448		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
 449
 450	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
 451
 452	return pwr_mgmt_ctrl;
 453}
 454
 455/*
 456 * Get the temperature level of the EMIF instance:
 457 * Reads the MR4 register of attached SDRAM parts to find out the temperature
 458 * level. If there are two parts attached(one on each CS), then the temperature
 459 * level for the EMIF instance is the higher of the two temperatures.
 460 */
 461static void get_temperature_level(struct emif_data *emif)
 462{
 463	u32		temp, temperature_level;
 464	void __iomem	*base;
 465
 466	base = emif->base;
 467
 468	/* Read mode register 4 */
 469	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
 470	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
 471	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
 472				MR4_SDRAM_REF_RATE_SHIFT;
 473
 474	if (emif->plat_data->device_info->cs1_used) {
 475		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
 476		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
 477		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
 478				>> MR4_SDRAM_REF_RATE_SHIFT;
 479		temperature_level = max(temp, temperature_level);
 480	}
 481
 482	/* treat everything less than nominal(3) in MR4 as nominal */
 483	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
 484		temperature_level = SDRAM_TEMP_NOMINAL;
 485
 486	/* if we get reserved value in MR4 persist with the existing value */
 487	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
 488		emif->temperature_level = temperature_level;
 489}
 490
 491/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 492 * setup_temperature_sensitive_regs() - set the timings for temperature
 493 * sensitive registers. This happens once at initialisation time based
 494 * on the temperature at boot time and subsequently based on the temperature
 495 * alert interrupt. Temperature alert can happen when the temperature
 496 * increases or drops. So this function can have the effect of either
 497 * derating the timings or going back to nominal values.
 498 */
 499static void setup_temperature_sensitive_regs(struct emif_data *emif,
 500		struct emif_regs *regs)
 501{
 502	u32		tim1, tim3, ref_ctrl, type;
 503	void __iomem	*base = emif->base;
 504	u32		temperature;
 505
 506	type = emif->plat_data->device_info->type;
 507
 508	tim1 = regs->sdram_tim1_shdw;
 509	tim3 = regs->sdram_tim3_shdw;
 510	ref_ctrl = regs->ref_ctrl_shdw;
 511
 512	/* No de-rating for non-lpddr2 devices */
 513	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
 514		goto out;
 515
 516	temperature = emif->temperature_level;
 517	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
 518		ref_ctrl = regs->ref_ctrl_shdw_derated;
 519	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
 520		tim1 = regs->sdram_tim1_shdw_derated;
 521		tim3 = regs->sdram_tim3_shdw_derated;
 522		ref_ctrl = regs->ref_ctrl_shdw_derated;
 523	}
 524
 525out:
 526	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
 527	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
 528	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
 529}
 530
 531static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
 532{
 533	u32		old_temp_level;
 534	irqreturn_t	ret = IRQ_HANDLED;
 535	struct emif_custom_configs *custom_configs;
 536
 537	spin_lock_irqsave(&emif_lock, irq_state);
 538	old_temp_level = emif->temperature_level;
 539	get_temperature_level(emif);
 540
 541	if (unlikely(emif->temperature_level == old_temp_level)) {
 542		goto out;
 543	} else if (!emif->curr_regs) {
 544		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
 545		goto out;
 546	}
 547
 548	custom_configs = emif->plat_data->custom_configs;
 549
 550	/*
 551	 * IF we detect higher than "nominal rating" from DDR sensor
 552	 * on an unsupported DDR part, shutdown system
 553	 */
 554	if (custom_configs && !(custom_configs->mask &
 555				EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
 556		if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
 557			dev_err(emif->dev,
 558				"%s:NOT Extended temperature capable memory. Converting MR4=0x%02x as shutdown event\n",
 559				__func__, emif->temperature_level);
 560			/*
 561			 * Temperature far too high - do kernel_power_off()
 562			 * from thread context
 563			 */
 564			emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
 565			ret = IRQ_WAKE_THREAD;
 566			goto out;
 567		}
 568	}
 569
 570	if (emif->temperature_level < old_temp_level ||
 571		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
 572		/*
 573		 * Temperature coming down - defer handling to thread OR
 574		 * Temperature far too high - do kernel_power_off() from
 575		 * thread context
 576		 */
 577		ret = IRQ_WAKE_THREAD;
 578	} else {
 579		/* Temperature is going up - handle immediately */
 580		setup_temperature_sensitive_regs(emif, emif->curr_regs);
 581		do_freq_update();
 582	}
 583
 584out:
 585	spin_unlock_irqrestore(&emif_lock, irq_state);
 586	return ret;
 587}
 588
 589static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
 590{
 591	u32			interrupts;
 592	struct emif_data	*emif = dev_id;
 593	void __iomem		*base = emif->base;
 594	struct device		*dev = emif->dev;
 595	irqreturn_t		ret = IRQ_HANDLED;
 596
 597	/* Save the status and clear it */
 598	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
 599	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
 600
 601	/*
 602	 * Handle temperature alert
 603	 * Temperature alert should be same for all ports
 604	 * So, it's enough to process it only for one of the ports
 605	 */
 606	if (interrupts & TA_SYS_MASK)
 607		ret = handle_temp_alert(base, emif);
 608
 609	if (interrupts & ERR_SYS_MASK)
 610		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
 611
 612	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
 613		/* Save the status and clear it */
 614		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
 615		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
 616
 617		if (interrupts & ERR_LL_MASK)
 618			dev_err(dev, "Access error from LL port - %x\n",
 619				interrupts);
 620	}
 621
 622	return ret;
 623}
 624
 625static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
 626{
 627	struct emif_data	*emif = dev_id;
 628
 629	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
 630		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
 631
 632		/* If we have Power OFF ability, use it, else try restarting */
 633		if (kernel_can_power_off()) {
 634			kernel_power_off();
 635		} else {
 636			WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
 637			kernel_restart("SDRAM Over-temp Emergency restart");
 638		}
 639		return IRQ_HANDLED;
 640	}
 641
 642	spin_lock_irqsave(&emif_lock, irq_state);
 643
 644	if (emif->curr_regs) {
 645		setup_temperature_sensitive_regs(emif, emif->curr_regs);
 646		do_freq_update();
 647	} else {
 648		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
 649	}
 650
 651	spin_unlock_irqrestore(&emif_lock, irq_state);
 652
 653	return IRQ_HANDLED;
 654}
 655
 656static void clear_all_interrupts(struct emif_data *emif)
 657{
 658	void __iomem	*base = emif->base;
 659
 660	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
 661		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
 662	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
 663		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
 664			base + EMIF_LL_OCP_INTERRUPT_STATUS);
 665}
 666
 667static void disable_and_clear_all_interrupts(struct emif_data *emif)
 668{
 669	void __iomem		*base = emif->base;
 670
 671	/* Disable all interrupts */
 672	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
 673		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
 674	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
 675		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
 676			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
 677
 678	/* Clear all interrupts */
 679	clear_all_interrupts(emif);
 680}
 681
 682static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
 683{
 684	u32		interrupts, type;
 685	void __iomem	*base = emif->base;
 686
 687	type = emif->plat_data->device_info->type;
 688
 689	clear_all_interrupts(emif);
 690
 691	/* Enable interrupts for SYS interface */
 692	interrupts = EN_ERR_SYS_MASK;
 693	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
 694		interrupts |= EN_TA_SYS_MASK;
 695	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
 696
 697	/* Enable interrupts for LL interface */
 698	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
 699		/* TA need not be enabled for LL */
 700		interrupts = EN_ERR_LL_MASK;
 701		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
 702	}
 703
 704	/* setup IRQ handlers */
 705	return devm_request_threaded_irq(emif->dev, irq,
 706				    emif_interrupt_handler,
 707				    emif_threaded_isr,
 708				    0, dev_name(emif->dev),
 709				    emif);
 710
 711}
 712
 713static void __init_or_module emif_onetime_settings(struct emif_data *emif)
 714{
 715	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
 716	void __iomem			*base = emif->base;
 717	const struct lpddr2_addressing	*addressing;
 718	const struct ddr_device_info	*device_info;
 719
 720	device_info = emif->plat_data->device_info;
 721	addressing = get_addressing_table(device_info);
 722
 723	/*
 724	 * Init power management settings
 725	 * We don't know the frequency yet. Use a high frequency
 726	 * value for a conservative timeout setting
 727	 */
 728	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
 729			emif->plat_data->ip_rev);
 730	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
 731	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
 732
 733	/* Init ZQ calibration settings */
 734	zq = get_zq_config_reg(addressing, device_info->cs1_used,
 735		device_info->cal_resistors_per_cs);
 736	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
 737
 738	/* Check temperature level temperature level*/
 739	get_temperature_level(emif);
 740	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
 741		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
 742
 743	/* Init temperature polling */
 744	temp_alert_cfg = get_temp_alert_config(addressing,
 745		emif->plat_data->custom_configs, device_info->cs1_used,
 746		device_info->io_width, get_emif_bus_width(emif));
 747	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
 748
 749	/*
 750	 * Program external PHY control registers that are not frequency
 751	 * dependent
 752	 */
 753	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
 754		return;
 755	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
 756	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
 757	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
 758	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
 759	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
 760	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
 761	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
 762	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
 763	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
 764	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
 765	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
 766	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
 767	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
 768	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
 769	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
 770	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
 771	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
 772	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
 773	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
 774	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
 775	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
 776}
 777
 778static void get_default_timings(struct emif_data *emif)
 779{
 780	struct emif_platform_data *pd = emif->plat_data;
 781
 782	pd->timings		= lpddr2_jedec_timings;
 783	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
 784
 785	dev_warn(emif->dev, "%s: using default timings\n", __func__);
 786}
 787
 788static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
 789		u32 ip_rev, struct device *dev)
 790{
 791	int valid;
 792
 793	valid = (type == DDR_TYPE_LPDDR2_S4 ||
 794			type == DDR_TYPE_LPDDR2_S2)
 795		&& (density >= DDR_DENSITY_64Mb
 796			&& density <= DDR_DENSITY_8Gb)
 797		&& (io_width >= DDR_IO_WIDTH_8
 798			&& io_width <= DDR_IO_WIDTH_32);
 799
 800	/* Combinations of EMIF and PHY revisions that we support today */
 801	switch (ip_rev) {
 802	case EMIF_4D:
 803		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
 804		break;
 805	case EMIF_4D5:
 806		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
 807		break;
 808	default:
 809		valid = 0;
 810	}
 811
 812	if (!valid)
 813		dev_err(dev, "%s: invalid DDR details\n", __func__);
 814	return valid;
 815}
 816
 817static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
 818		struct device *dev)
 819{
 820	int valid = 1;
 821
 822	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
 823		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
 824		valid = cust_cfgs->lpmode_freq_threshold &&
 825			cust_cfgs->lpmode_timeout_performance &&
 826			cust_cfgs->lpmode_timeout_power;
 827
 828	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
 829		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
 830
 831	if (!valid)
 832		dev_warn(dev, "%s: invalid custom configs\n", __func__);
 833
 834	return valid;
 835}
 836
 837#if defined(CONFIG_OF)
 838static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
 839		struct emif_data *emif)
 840{
 841	struct emif_custom_configs	*cust_cfgs = NULL;
 842	int				len;
 843	const __be32			*lpmode, *poll_intvl;
 844
 845	lpmode = of_get_property(np_emif, "low-power-mode", &len);
 846	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
 847
 848	if (lpmode || poll_intvl)
 849		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
 850			GFP_KERNEL);
 851
 852	if (!cust_cfgs)
 853		return;
 854
 855	if (lpmode) {
 856		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
 857		cust_cfgs->lpmode = be32_to_cpup(lpmode);
 858		of_property_read_u32(np_emif,
 859				"low-power-mode-timeout-performance",
 860				&cust_cfgs->lpmode_timeout_performance);
 861		of_property_read_u32(np_emif,
 862				"low-power-mode-timeout-power",
 863				&cust_cfgs->lpmode_timeout_power);
 864		of_property_read_u32(np_emif,
 865				"low-power-mode-freq-threshold",
 866				&cust_cfgs->lpmode_freq_threshold);
 867	}
 868
 869	if (poll_intvl) {
 870		cust_cfgs->mask |=
 871				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
 872		cust_cfgs->temp_alert_poll_interval_ms =
 873						be32_to_cpup(poll_intvl);
 874	}
 875
 876	if (of_find_property(np_emif, "extended-temp-part", &len))
 877		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
 878
 879	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
 880		devm_kfree(emif->dev, cust_cfgs);
 881		return;
 882	}
 883
 884	emif->plat_data->custom_configs = cust_cfgs;
 885}
 886
 887static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
 888		struct device_node *np_ddr,
 889		struct ddr_device_info *dev_info)
 890{
 891	u32 density = 0, io_width = 0;
 892	int len;
 893
 894	if (of_find_property(np_emif, "cs1-used", &len))
 895		dev_info->cs1_used = true;
 896
 897	if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
 898		dev_info->cal_resistors_per_cs = true;
 899
 900	if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s4"))
 901		dev_info->type = DDR_TYPE_LPDDR2_S4;
 902	else if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s2"))
 903		dev_info->type = DDR_TYPE_LPDDR2_S2;
 904
 905	of_property_read_u32(np_ddr, "density", &density);
 906	of_property_read_u32(np_ddr, "io-width", &io_width);
 907
 908	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
 909	if (density & (density - 1))
 910		dev_info->density = 0;
 911	else
 912		dev_info->density = __fls(density) - 5;
 913
 914	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
 915	if (io_width & (io_width - 1))
 916		dev_info->io_width = 0;
 917	else
 918		dev_info->io_width = __fls(io_width) - 1;
 919}
 920
 921static struct emif_data * __init_or_module of_get_memory_device_details(
 922		struct device_node *np_emif, struct device *dev)
 923{
 924	struct emif_data		*emif = NULL;
 925	struct ddr_device_info		*dev_info = NULL;
 926	struct emif_platform_data	*pd = NULL;
 927	struct device_node		*np_ddr;
 928	int				len;
 929
 930	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
 931	if (!np_ddr)
 932		goto error;
 933	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
 934	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
 935	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
 936
 937	if (!emif || !pd || !dev_info) {
 938		dev_err(dev, "%s: Out of memory!!\n",
 939			__func__);
 940		goto error;
 941	}
 942
 943	emif->plat_data		= pd;
 944	pd->device_info		= dev_info;
 945	emif->dev		= dev;
 946	emif->np_ddr		= np_ddr;
 947	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
 948
 949	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
 950		emif->plat_data->ip_rev = EMIF_4D;
 951	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
 952		emif->plat_data->ip_rev = EMIF_4D5;
 953
 954	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
 955
 956	if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
 957		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
 958
 959	of_get_ddr_info(np_emif, np_ddr, dev_info);
 960	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
 961			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
 962			emif->dev)) {
 963		dev_err(dev, "%s: invalid device data!!\n", __func__);
 964		goto error;
 965	}
 966	/*
 967	 * For EMIF instances other than EMIF1 see if the devices connected
 968	 * are exactly same as on EMIF1(which is typically the case). If so,
 969	 * mark it as a duplicate of EMIF1. This will save some memory and
 970	 * computation.
 971	 */
 972	if (emif1 && emif1->np_ddr == np_ddr) {
 973		emif->duplicate = true;
 974		goto out;
 975	} else if (emif1) {
 976		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
 977			__func__);
 978	}
 979
 980	of_get_custom_configs(np_emif, emif);
 981	emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
 982					emif->plat_data->device_info->type,
 983					&emif->plat_data->timings_arr_size);
 984
 985	emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
 986	goto out;
 987
 988error:
 989	return NULL;
 990out:
 991	return emif;
 992}
 993
 994#else
 995
 996static struct emif_data * __init_or_module of_get_memory_device_details(
 997		struct device_node *np_emif, struct device *dev)
 998{
 999	return NULL;
1000}
1001#endif
1002
1003static struct emif_data *__init_or_module get_device_details(
1004		struct platform_device *pdev)
1005{
1006	u32				size;
1007	struct emif_data		*emif = NULL;
1008	struct ddr_device_info		*dev_info;
1009	struct emif_custom_configs	*cust_cfgs;
1010	struct emif_platform_data	*pd;
1011	struct device			*dev;
1012	void				*temp;
1013
1014	pd = pdev->dev.platform_data;
1015	dev = &pdev->dev;
1016
1017	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
1018			pd->device_info->density, pd->device_info->io_width,
1019			pd->phy_type, pd->ip_rev, dev))) {
1020		dev_err(dev, "%s: invalid device data\n", __func__);
1021		goto error;
1022	}
1023
1024	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1025	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1026	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1027
1028	if (!emif || !temp || !dev_info)
 
1029		goto error;
 
1030
1031	memcpy(temp, pd, sizeof(*pd));
1032	pd = temp;
1033	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1034
1035	pd->device_info		= dev_info;
1036	emif->plat_data		= pd;
1037	emif->dev		= dev;
1038	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1039
1040	/*
1041	 * For EMIF instances other than EMIF1 see if the devices connected
1042	 * are exactly same as on EMIF1(which is typically the case). If so,
1043	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1044	 * This will save some memory and some computation later.
1045	 */
1046	emif->duplicate = emif1 && (memcmp(dev_info,
1047		emif1->plat_data->device_info,
1048		sizeof(struct ddr_device_info)) == 0);
1049
1050	if (emif->duplicate) {
1051		pd->timings = NULL;
1052		pd->min_tck = NULL;
1053		goto out;
1054	} else if (emif1) {
1055		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1056			__func__);
1057	}
1058
1059	/*
1060	 * Copy custom configs - ignore allocation error, if any, as
1061	 * custom_configs is not very critical
1062	 */
1063	cust_cfgs = pd->custom_configs;
1064	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1065		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1066		if (temp)
1067			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
 
 
 
1068		pd->custom_configs = temp;
1069	}
1070
1071	/*
1072	 * Copy timings and min-tck values from platform data. If it is not
1073	 * available or if memory allocation fails, use JEDEC defaults
1074	 */
1075	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1076	if (pd->timings) {
1077		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1078		if (temp) {
1079			memcpy(temp, pd->timings, size);
1080			pd->timings = temp;
1081		} else {
 
 
1082			get_default_timings(emif);
1083		}
1084	} else {
1085		get_default_timings(emif);
1086	}
1087
1088	if (pd->min_tck) {
1089		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1090		if (temp) {
1091			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1092			pd->min_tck = temp;
1093		} else {
 
 
1094			pd->min_tck = &lpddr2_jedec_min_tck;
1095		}
1096	} else {
1097		pd->min_tck = &lpddr2_jedec_min_tck;
1098	}
1099
1100out:
1101	return emif;
1102
1103error:
1104	return NULL;
1105}
1106
1107static int __init_or_module emif_probe(struct platform_device *pdev)
1108{
1109	struct emif_data	*emif;
1110	int			irq, ret;
1111
1112	if (pdev->dev.of_node)
1113		emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
1114	else
1115		emif = get_device_details(pdev);
1116
 
1117	if (!emif) {
1118		pr_err("%s: error getting device data\n", __func__);
1119		goto error;
1120	}
1121
1122	list_add(&emif->node, &device_list);
 
1123
1124	/* Save pointers to each other in emif and device structures */
1125	emif->dev = &pdev->dev;
1126	platform_set_drvdata(pdev, emif);
1127
1128	emif->base = devm_platform_ioremap_resource(pdev, 0);
1129	if (IS_ERR(emif->base))
 
 
 
 
 
 
 
 
 
1130		goto error;
 
1131
1132	irq = platform_get_irq(pdev, 0);
1133	if (irq < 0)
 
 
1134		goto error;
 
1135
1136	emif_onetime_settings(emif);
1137	emif_debugfs_init(emif);
1138	disable_and_clear_all_interrupts(emif);
1139	ret = setup_interrupts(emif, irq);
1140	if (ret)
1141		goto error;
1142
1143	/* One-time actions taken on probing the first device */
1144	if (!emif1) {
1145		emif1 = emif;
 
1146
1147		/*
1148		 * TODO: register notifiers for frequency and voltage
1149		 * change here once the respective frameworks are
1150		 * available
1151		 */
1152	}
1153
1154	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1155		__func__, emif->base, irq);
1156
1157	return 0;
1158error:
1159	return -ENODEV;
1160}
1161
1162static void __exit emif_remove(struct platform_device *pdev)
1163{
1164	struct emif_data *emif = platform_get_drvdata(pdev);
1165
1166	emif_debugfs_exit(emif);
 
 
1167}
1168
1169static void emif_shutdown(struct platform_device *pdev)
1170{
1171	struct emif_data	*emif = platform_get_drvdata(pdev);
1172
1173	disable_and_clear_all_interrupts(emif);
1174}
1175
1176#if defined(CONFIG_OF)
1177static const struct of_device_id emif_of_match[] = {
1178		{ .compatible = "ti,emif-4d" },
1179		{ .compatible = "ti,emif-4d5" },
1180		{},
1181};
1182MODULE_DEVICE_TABLE(of, emif_of_match);
1183#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1184
1185static struct platform_driver emif_driver = {
1186	.remove_new	= __exit_p(emif_remove),
1187	.shutdown	= emif_shutdown,
1188	.driver = {
1189		.name = "emif",
1190		.of_match_table = of_match_ptr(emif_of_match),
1191	},
1192};
1193
1194module_platform_driver_probe(emif_driver, emif_probe);
 
 
 
 
 
 
 
 
1195
 
 
1196MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1197MODULE_LICENSE("GPL");
1198MODULE_ALIAS("platform:emif");
1199MODULE_AUTHOR("Texas Instruments Inc");
v3.5.6
 
   1/*
   2 * EMIF driver
   3 *
   4 * Copyright (C) 2012 Texas Instruments, Inc.
   5 *
   6 * Aneesh V <aneesh@ti.com>
   7 * Santosh Shilimkar <santosh.shilimkar@ti.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
 
  13#include <linux/kernel.h>
  14#include <linux/reboot.h>
  15#include <linux/platform_data/emif_plat.h>
  16#include <linux/io.h>
  17#include <linux/device.h>
  18#include <linux/platform_device.h>
  19#include <linux/interrupt.h>
  20#include <linux/slab.h>
 
  21#include <linux/debugfs.h>
  22#include <linux/seq_file.h>
  23#include <linux/module.h>
  24#include <linux/list.h>
  25#include <linux/spinlock.h>
  26#include <memory/jedec_ddr.h>
 
  27#include "emif.h"
 
 
  28
  29/**
  30 * struct emif_data - Per device static data for driver's use
  31 * @duplicate:			Whether the DDR devices attached to this EMIF
  32 *				instance are exactly same as that on EMIF1. In
  33 *				this case we can save some memory and processing
  34 * @temperature_level:		Maximum temperature of LPDDR2 devices attached
  35 *				to this EMIF - read from MR4 register. If there
  36 *				are two devices attached to this EMIF, this
  37 *				value is the maximum of the two temperature
  38 *				levels.
  39 * @node:			node in the device list
  40 * @base:			base address of memory-mapped IO registers.
  41 * @dev:			device pointer.
  42 * @addressing			table with addressing information from the spec
  43 * @regs_cache:			An array of 'struct emif_regs' that stores
  44 *				calculated register values for different
  45 *				frequencies, to avoid re-calculating them on
  46 *				each DVFS transition.
  47 * @curr_regs:			The set of register values used in the last
  48 *				frequency change (i.e. corresponding to the
  49 *				frequency in effect at the moment)
  50 * @plat_data:			Pointer to saved platform data.
  51 * @debugfs_root:		dentry to the root folder for EMIF in debugfs
 
  52 */
  53struct emif_data {
  54	u8				duplicate;
  55	u8				temperature_level;
  56	u8				lpmode;
  57	struct list_head		node;
  58	unsigned long			irq_state;
  59	void __iomem			*base;
  60	struct device			*dev;
  61	const struct lpddr2_addressing	*addressing;
  62	struct emif_regs		*regs_cache[EMIF_MAX_NUM_FREQUENCIES];
  63	struct emif_regs		*curr_regs;
  64	struct emif_platform_data	*plat_data;
  65	struct dentry			*debugfs_root;
 
  66};
  67
  68static struct emif_data *emif1;
  69static spinlock_t	emif_lock;
  70static unsigned long	irq_state;
  71static u32		t_ck; /* DDR clock period in ps */
  72static LIST_HEAD(device_list);
  73
 
  74static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
  75	struct emif_regs *regs)
  76{
  77	u32 type = emif->plat_data->device_info->type;
  78	u32 ip_rev = emif->plat_data->ip_rev;
  79
  80	seq_printf(s, "EMIF register cache dump for %dMHz\n",
  81		regs->freq/1000000);
  82
  83	seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
  84	seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
  85	seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
  86	seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
  87
  88	if (ip_rev == EMIF_4D) {
  89		seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
  90			regs->read_idle_ctrl_shdw_normal);
  91		seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
  92			regs->read_idle_ctrl_shdw_volt_ramp);
  93	} else if (ip_rev == EMIF_4D5) {
  94		seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
  95			regs->dll_calib_ctrl_shdw_normal);
  96		seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
  97			regs->dll_calib_ctrl_shdw_volt_ramp);
  98	}
  99
 100	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
 101		seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
 102			regs->ref_ctrl_shdw_derated);
 103		seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
 104			regs->sdram_tim1_shdw_derated);
 105		seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
 106			regs->sdram_tim3_shdw_derated);
 107	}
 108}
 109
 110static int emif_regdump_show(struct seq_file *s, void *unused)
 111{
 112	struct emif_data	*emif	= s->private;
 113	struct emif_regs	**regs_cache;
 114	int			i;
 115
 116	if (emif->duplicate)
 117		regs_cache = emif1->regs_cache;
 118	else
 119		regs_cache = emif->regs_cache;
 120
 121	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
 122		do_emif_regdump_show(s, emif, regs_cache[i]);
 123		seq_printf(s, "\n");
 124	}
 125
 126	return 0;
 127}
 128
 129static int emif_regdump_open(struct inode *inode, struct file *file)
 130{
 131	return single_open(file, emif_regdump_show, inode->i_private);
 132}
 133
 134static const struct file_operations emif_regdump_fops = {
 135	.open			= emif_regdump_open,
 136	.read			= seq_read,
 137	.release		= single_release,
 138};
 139
 140static int emif_mr4_show(struct seq_file *s, void *unused)
 141{
 142	struct emif_data *emif = s->private;
 143
 144	seq_printf(s, "MR4=%d\n", emif->temperature_level);
 145	return 0;
 146}
 147
 148static int emif_mr4_open(struct inode *inode, struct file *file)
 149{
 150	return single_open(file, emif_mr4_show, inode->i_private);
 151}
 152
 153static const struct file_operations emif_mr4_fops = {
 154	.open			= emif_mr4_open,
 155	.read			= seq_read,
 156	.release		= single_release,
 157};
 158
 159static int __init_or_module emif_debugfs_init(struct emif_data *emif)
 160{
 161	struct dentry	*dentry;
 162	int		ret;
 163
 164	dentry = debugfs_create_dir(dev_name(emif->dev), NULL);
 165	if (IS_ERR(dentry)) {
 166		ret = PTR_ERR(dentry);
 167		goto err0;
 168	}
 169	emif->debugfs_root = dentry;
 170
 171	dentry = debugfs_create_file("regcache_dump", S_IRUGO,
 172			emif->debugfs_root, emif, &emif_regdump_fops);
 173	if (IS_ERR(dentry)) {
 174		ret = PTR_ERR(dentry);
 175		goto err1;
 176	}
 177
 178	dentry = debugfs_create_file("mr4", S_IRUGO,
 179			emif->debugfs_root, emif, &emif_mr4_fops);
 180	if (IS_ERR(dentry)) {
 181		ret = PTR_ERR(dentry);
 182		goto err1;
 183	}
 184
 185	return 0;
 186err1:
 187	debugfs_remove_recursive(emif->debugfs_root);
 188err0:
 189	return ret;
 190}
 191
 192static void __exit emif_debugfs_exit(struct emif_data *emif)
 193{
 194	debugfs_remove_recursive(emif->debugfs_root);
 195	emif->debugfs_root = NULL;
 196}
 
 
 
 
 
 197
 198/*
 199 * Calculate the period of DDR clock from frequency value
 200 */
 201static void set_ddr_clk_period(u32 freq)
 202{
 203	/* Divide 10^12 by frequency to get period in ps */
 204	t_ck = (u32)DIV_ROUND_UP_ULL(1000000000000ull, freq);
 205}
 
 206
 207/*
 208 * Get bus width used by EMIF. Note that this may be different from the
 209 * bus width of the DDR devices used. For instance two 16-bit DDR devices
 210 * may be connected to a given CS of EMIF. In this case bus width as far
 211 * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
 212 */
 213static u32 get_emif_bus_width(struct emif_data *emif)
 214{
 215	u32		width;
 216	void __iomem	*base = emif->base;
 217
 218	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
 219			>> NARROW_MODE_SHIFT;
 220	width = width == 0 ? 32 : 16;
 221
 222	return width;
 223}
 224
 225/*
 226 * Get the CL from SDRAM_CONFIG register
 227 */
 228static u32 get_cl(struct emif_data *emif)
 229{
 230	u32		cl;
 231	void __iomem	*base = emif->base;
 232
 233	cl = (readl(base + EMIF_SDRAM_CONFIG) & CL_MASK) >> CL_SHIFT;
 234
 235	return cl;
 236}
 237
 238static void set_lpmode(struct emif_data *emif, u8 lpmode)
 239{
 240	u32 temp;
 241	void __iomem *base = emif->base;
 242
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 243	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
 244	temp &= ~LP_MODE_MASK;
 245	temp |= (lpmode << LP_MODE_SHIFT);
 246	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
 247}
 248
 249static void do_freq_update(void)
 250{
 251	struct emif_data *emif;
 252
 253	/*
 254	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
 255	 *
 256	 * i728 DESCRIPTION:
 257	 * The EMIF automatically puts the SDRAM into self-refresh mode
 258	 * after the EMIF has not performed accesses during
 259	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
 260	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
 261	 * to 0x2. If during a small window the following three events
 262	 * occur:
 263	 * - The SR_TIMING counter expires
 264	 * - And frequency change is requested
 265	 * - And OCP access is requested
 266	 * Then it causes instable clock on the DDR interface.
 267	 *
 268	 * WORKAROUND
 269	 * To avoid the occurrence of the three events, the workaround
 270	 * is to disable the self-refresh when requesting a frequency
 271	 * change. Before requesting a frequency change the software must
 272	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
 273	 * frequency change has been done, the software can reprogram
 274	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
 275	 */
 276	list_for_each_entry(emif, &device_list, node) {
 277		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
 278			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
 279	}
 280
 281	/*
 282	 * TODO: Do FREQ_UPDATE here when an API
 283	 * is available for this as part of the new
 284	 * clock framework
 285	 */
 286
 287	list_for_each_entry(emif, &device_list, node) {
 288		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
 289			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
 290	}
 291}
 292
 293/* Find addressing table entry based on the device's type and density */
 294static const struct lpddr2_addressing *get_addressing_table(
 295	const struct ddr_device_info *device_info)
 296{
 297	u32		index, type, density;
 298
 299	type = device_info->type;
 300	density = device_info->density;
 301
 302	switch (type) {
 303	case DDR_TYPE_LPDDR2_S4:
 304		index = density - 1;
 305		break;
 306	case DDR_TYPE_LPDDR2_S2:
 307		switch (density) {
 308		case DDR_DENSITY_1Gb:
 309		case DDR_DENSITY_2Gb:
 310			index = density + 3;
 311			break;
 312		default:
 313			index = density - 1;
 314		}
 315		break;
 316	default:
 317		return NULL;
 318	}
 319
 320	return &lpddr2_jedec_addressing_table[index];
 321}
 322
 323/*
 324 * Find the the right timing table from the array of timing
 325 * tables of the device using DDR clock frequency
 326 */
 327static const struct lpddr2_timings *get_timings_table(struct emif_data *emif,
 328		u32 freq)
 329{
 330	u32				i, min, max, freq_nearest;
 331	const struct lpddr2_timings	*timings = NULL;
 332	const struct lpddr2_timings	*timings_arr = emif->plat_data->timings;
 333	struct				device *dev = emif->dev;
 334
 335	/* Start with a very high frequency - 1GHz */
 336	freq_nearest = 1000000000;
 337
 338	/*
 339	 * Find the timings table such that:
 340	 *  1. the frequency range covers the required frequency(safe) AND
 341	 *  2. the max_freq is closest to the required frequency(optimal)
 342	 */
 343	for (i = 0; i < emif->plat_data->timings_arr_size; i++) {
 344		max = timings_arr[i].max_freq;
 345		min = timings_arr[i].min_freq;
 346		if ((freq >= min) && (freq <= max) && (max < freq_nearest)) {
 347			freq_nearest = max;
 348			timings = &timings_arr[i];
 349		}
 350	}
 351
 352	if (!timings)
 353		dev_err(dev, "%s: couldn't find timings for - %dHz\n",
 354			__func__, freq);
 355
 356	dev_dbg(dev, "%s: timings table: freq %d, speed bin freq %d\n",
 357		__func__, freq, freq_nearest);
 358
 359	return timings;
 360}
 361
 362static u32 get_sdram_ref_ctrl_shdw(u32 freq,
 363		const struct lpddr2_addressing *addressing)
 364{
 365	u32 ref_ctrl_shdw = 0, val = 0, freq_khz, t_refi;
 366
 367	/* Scale down frequency and t_refi to avoid overflow */
 368	freq_khz = freq / 1000;
 369	t_refi = addressing->tREFI_ns / 100;
 370
 371	/*
 372	 * refresh rate to be set is 'tREFI(in us) * freq in MHz
 373	 * division by 10000 to account for change in units
 374	 */
 375	val = t_refi * freq_khz / 10000;
 376	ref_ctrl_shdw |= val << REFRESH_RATE_SHIFT;
 377
 378	return ref_ctrl_shdw;
 379}
 380
 381static u32 get_sdram_tim_1_shdw(const struct lpddr2_timings *timings,
 382		const struct lpddr2_min_tck *min_tck,
 383		const struct lpddr2_addressing *addressing)
 384{
 385	u32 tim1 = 0, val = 0;
 386
 387	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
 388	tim1 |= val << T_WTR_SHIFT;
 389
 390	if (addressing->num_banks == B8)
 391		val = DIV_ROUND_UP(timings->tFAW, t_ck*4);
 392	else
 393		val = max(min_tck->tRRD, DIV_ROUND_UP(timings->tRRD, t_ck));
 394	tim1 |= (val - 1) << T_RRD_SHIFT;
 395
 396	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab, t_ck) - 1;
 397	tim1 |= val << T_RC_SHIFT;
 398
 399	val = max(min_tck->tRASmin, DIV_ROUND_UP(timings->tRAS_min, t_ck));
 400	tim1 |= (val - 1) << T_RAS_SHIFT;
 401
 402	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
 403	tim1 |= val << T_WR_SHIFT;
 404
 405	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD, t_ck)) - 1;
 406	tim1 |= val << T_RCD_SHIFT;
 407
 408	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab, t_ck)) - 1;
 409	tim1 |= val << T_RP_SHIFT;
 410
 411	return tim1;
 412}
 413
 414static u32 get_sdram_tim_1_shdw_derated(const struct lpddr2_timings *timings,
 415		const struct lpddr2_min_tck *min_tck,
 416		const struct lpddr2_addressing *addressing)
 417{
 418	u32 tim1 = 0, val = 0;
 419
 420	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
 421	tim1 = val << T_WTR_SHIFT;
 422
 423	/*
 424	 * tFAW is approximately 4 times tRRD. So add 1875*4 = 7500ps
 425	 * to tFAW for de-rating
 426	 */
 427	if (addressing->num_banks == B8) {
 428		val = DIV_ROUND_UP(timings->tFAW + 7500, 4 * t_ck) - 1;
 429	} else {
 430		val = DIV_ROUND_UP(timings->tRRD + 1875, t_ck);
 431		val = max(min_tck->tRRD, val) - 1;
 432	}
 433	tim1 |= val << T_RRD_SHIFT;
 434
 435	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab + 1875, t_ck);
 436	tim1 |= (val - 1) << T_RC_SHIFT;
 437
 438	val = DIV_ROUND_UP(timings->tRAS_min + 1875, t_ck);
 439	val = max(min_tck->tRASmin, val) - 1;
 440	tim1 |= val << T_RAS_SHIFT;
 441
 442	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
 443	tim1 |= val << T_WR_SHIFT;
 444
 445	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD + 1875, t_ck));
 446	tim1 |= (val - 1) << T_RCD_SHIFT;
 447
 448	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab + 1875, t_ck));
 449	tim1 |= (val - 1) << T_RP_SHIFT;
 450
 451	return tim1;
 452}
 453
 454static u32 get_sdram_tim_2_shdw(const struct lpddr2_timings *timings,
 455		const struct lpddr2_min_tck *min_tck,
 456		const struct lpddr2_addressing *addressing,
 457		u32 type)
 458{
 459	u32 tim2 = 0, val = 0;
 460
 461	val = min_tck->tCKE - 1;
 462	tim2 |= val << T_CKE_SHIFT;
 463
 464	val = max(min_tck->tRTP, DIV_ROUND_UP(timings->tRTP, t_ck)) - 1;
 465	tim2 |= val << T_RTP_SHIFT;
 466
 467	/* tXSNR = tRFCab_ps + 10 ns(tRFCab_ps for LPDDR2). */
 468	val = DIV_ROUND_UP(addressing->tRFCab_ps + 10000, t_ck) - 1;
 469	tim2 |= val << T_XSNR_SHIFT;
 470
 471	/* XSRD same as XSNR for LPDDR2 */
 472	tim2 |= val << T_XSRD_SHIFT;
 473
 474	val = max(min_tck->tXP, DIV_ROUND_UP(timings->tXP, t_ck)) - 1;
 475	tim2 |= val << T_XP_SHIFT;
 476
 477	return tim2;
 478}
 479
 480static u32 get_sdram_tim_3_shdw(const struct lpddr2_timings *timings,
 481		const struct lpddr2_min_tck *min_tck,
 482		const struct lpddr2_addressing *addressing,
 483		u32 type, u32 ip_rev, u32 derated)
 484{
 485	u32 tim3 = 0, val = 0, t_dqsck;
 486
 487	val = timings->tRAS_max_ns / addressing->tREFI_ns - 1;
 488	val = val > 0xF ? 0xF : val;
 489	tim3 |= val << T_RAS_MAX_SHIFT;
 490
 491	val = DIV_ROUND_UP(addressing->tRFCab_ps, t_ck) - 1;
 492	tim3 |= val << T_RFC_SHIFT;
 493
 494	t_dqsck = (derated == EMIF_DERATED_TIMINGS) ?
 495		timings->tDQSCK_max_derated : timings->tDQSCK_max;
 496	if (ip_rev == EMIF_4D5)
 497		val = DIV_ROUND_UP(t_dqsck + 1000, t_ck) - 1;
 498	else
 499		val = DIV_ROUND_UP(t_dqsck, t_ck) - 1;
 500
 501	tim3 |= val << T_TDQSCKMAX_SHIFT;
 502
 503	val = DIV_ROUND_UP(timings->tZQCS, t_ck) - 1;
 504	tim3 |= val << ZQ_ZQCS_SHIFT;
 505
 506	val = DIV_ROUND_UP(timings->tCKESR, t_ck);
 507	val = max(min_tck->tCKESR, val) - 1;
 508	tim3 |= val << T_CKESR_SHIFT;
 509
 510	if (ip_rev == EMIF_4D5) {
 511		tim3 |= (EMIF_T_CSTA - 1) << T_CSTA_SHIFT;
 512
 513		val = DIV_ROUND_UP(EMIF_T_PDLL_UL, 128) - 1;
 514		tim3 |= val << T_PDLL_UL_SHIFT;
 515	}
 516
 517	return tim3;
 518}
 519
 520static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
 521		bool cs1_used, bool cal_resistors_per_cs)
 522{
 523	u32 zq = 0, val = 0;
 524
 525	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
 526	zq |= val << ZQ_REFINTERVAL_SHIFT;
 527
 528	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
 529	zq |= val << ZQ_ZQCL_MULT_SHIFT;
 530
 531	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
 532	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
 533
 534	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
 535
 536	if (cal_resistors_per_cs)
 537		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
 538	else
 539		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
 540
 541	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
 542
 543	val = cs1_used ? 1 : 0;
 544	zq |= val << ZQ_CS1EN_SHIFT;
 545
 546	return zq;
 547}
 548
 549static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
 550		const struct emif_custom_configs *custom_configs, bool cs1_used,
 551		u32 sdram_io_width, u32 emif_bus_width)
 552{
 553	u32 alert = 0, interval, devcnt;
 554
 555	if (custom_configs && (custom_configs->mask &
 556				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
 557		interval = custom_configs->temp_alert_poll_interval_ms;
 558	else
 559		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
 560
 561	interval *= 1000000;			/* Convert to ns */
 562	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
 563	alert |= (interval << TA_REFINTERVAL_SHIFT);
 564
 565	/*
 566	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
 567	 * also to this form and subtract to get TA_DEVCNT, which is
 568	 * in log2(x) form.
 569	 */
 570	emif_bus_width = __fls(emif_bus_width) - 1;
 571	devcnt = emif_bus_width - sdram_io_width;
 572	alert |= devcnt << TA_DEVCNT_SHIFT;
 573
 574	/* DEVWDT is in 'log2(x) - 3' form */
 575	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
 576
 577	alert |= 1 << TA_SFEXITEN_SHIFT;
 578	alert |= 1 << TA_CS0EN_SHIFT;
 579	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
 580
 581	return alert;
 582}
 583
 584static u32 get_read_idle_ctrl_shdw(u8 volt_ramp)
 585{
 586	u32 idle = 0, val = 0;
 587
 588	/*
 589	 * Maximum value in normal conditions and increased frequency
 590	 * when voltage is ramping
 591	 */
 592	if (volt_ramp)
 593		val = READ_IDLE_INTERVAL_DVFS / t_ck / 64 - 1;
 594	else
 595		val = 0x1FF;
 596
 597	/*
 598	 * READ_IDLE_CTRL register in EMIF4D has same offset and fields
 599	 * as DLL_CALIB_CTRL in EMIF4D5, so use the same shifts
 600	 */
 601	idle |= val << DLL_CALIB_INTERVAL_SHIFT;
 602	idle |= EMIF_READ_IDLE_LEN_VAL << ACK_WAIT_SHIFT;
 603
 604	return idle;
 605}
 606
 607static u32 get_dll_calib_ctrl_shdw(u8 volt_ramp)
 608{
 609	u32 calib = 0, val = 0;
 610
 611	if (volt_ramp == DDR_VOLTAGE_RAMPING)
 612		val = DLL_CALIB_INTERVAL_DVFS / t_ck / 16 - 1;
 613	else
 614		val = 0; /* Disabled when voltage is stable */
 615
 616	calib |= val << DLL_CALIB_INTERVAL_SHIFT;
 617	calib |= DLL_CALIB_ACK_WAIT_VAL << ACK_WAIT_SHIFT;
 618
 619	return calib;
 620}
 621
 622static u32 get_ddr_phy_ctrl_1_attilaphy_4d(const struct lpddr2_timings *timings,
 623	u32 freq, u8 RL)
 624{
 625	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_ATTILAPHY, val = 0;
 626
 627	val = RL + DIV_ROUND_UP(timings->tDQSCK_max, t_ck) - 1;
 628	phy |= val << READ_LATENCY_SHIFT_4D;
 629
 630	if (freq <= 100000000)
 631		val = EMIF_DLL_SLAVE_DLY_CTRL_100_MHZ_AND_LESS_ATTILAPHY;
 632	else if (freq <= 200000000)
 633		val = EMIF_DLL_SLAVE_DLY_CTRL_200_MHZ_ATTILAPHY;
 634	else
 635		val = EMIF_DLL_SLAVE_DLY_CTRL_400_MHZ_ATTILAPHY;
 636
 637	phy |= val << DLL_SLAVE_DLY_CTRL_SHIFT_4D;
 638
 639	return phy;
 640}
 641
 642static u32 get_phy_ctrl_1_intelliphy_4d5(u32 freq, u8 cl)
 643{
 644	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_INTELLIPHY, half_delay;
 645
 646	/*
 647	 * DLL operates at 266 MHz. If DDR frequency is near 266 MHz,
 648	 * half-delay is not needed else set half-delay
 649	 */
 650	if (freq >= 265000000 && freq < 267000000)
 651		half_delay = 0;
 652	else
 653		half_delay = 1;
 654
 655	phy |= half_delay << DLL_HALF_DELAY_SHIFT_4D5;
 656	phy |= ((cl + DIV_ROUND_UP(EMIF_PHY_TOTAL_READ_LATENCY_INTELLIPHY_PS,
 657			t_ck) - 1) << READ_LATENCY_SHIFT_4D5);
 658
 659	return phy;
 660}
 661
 662static u32 get_ext_phy_ctrl_2_intelliphy_4d5(void)
 663{
 664	u32 fifo_we_slave_ratio;
 665
 666	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
 667		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
 668
 669	return fifo_we_slave_ratio | fifo_we_slave_ratio << 11 |
 670		fifo_we_slave_ratio << 22;
 671}
 672
 673static u32 get_ext_phy_ctrl_3_intelliphy_4d5(void)
 674{
 675	u32 fifo_we_slave_ratio;
 676
 677	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
 678		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
 679
 680	return fifo_we_slave_ratio >> 10 | fifo_we_slave_ratio << 1 |
 681		fifo_we_slave_ratio << 12 | fifo_we_slave_ratio << 23;
 682}
 683
 684static u32 get_ext_phy_ctrl_4_intelliphy_4d5(void)
 685{
 686	u32 fifo_we_slave_ratio;
 687
 688	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
 689		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
 690
 691	return fifo_we_slave_ratio >> 9 | fifo_we_slave_ratio << 2 |
 692		fifo_we_slave_ratio << 13;
 693}
 694
 695static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
 696{
 697	u32 pwr_mgmt_ctrl	= 0, timeout;
 698	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
 699	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
 700	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
 701	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
 
 
 702
 703	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
 704
 705	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
 706		lpmode		= cust_cfgs->lpmode;
 707		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
 708		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
 709		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
 710	}
 711
 712	/* Timeout based on DDR frequency */
 713	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
 714
 715	/* The value to be set in register is "log2(timeout) - 3" */
 
 
 
 
 716	if (timeout < 16) {
 717		timeout = 0;
 718	} else {
 
 
 719		timeout = __fls(timeout) - 3;
 720		if (timeout & (timeout - 1))
 721			timeout++;
 722	}
 723
 724	switch (lpmode) {
 725	case EMIF_LP_MODE_CLOCK_STOP:
 726		pwr_mgmt_ctrl = (timeout << CS_TIM_SHIFT) |
 727					SR_TIM_MASK | PD_TIM_MASK;
 728		break;
 729	case EMIF_LP_MODE_SELF_REFRESH:
 730		/* Workaround for errata i735 */
 731		if (timeout < 6)
 732			timeout = 6;
 733
 734		pwr_mgmt_ctrl = (timeout << SR_TIM_SHIFT) |
 735					CS_TIM_MASK | PD_TIM_MASK;
 736		break;
 737	case EMIF_LP_MODE_PWR_DN:
 738		pwr_mgmt_ctrl = (timeout << PD_TIM_SHIFT) |
 739					CS_TIM_MASK | SR_TIM_MASK;
 740		break;
 741	case EMIF_LP_MODE_DISABLE:
 742	default:
 743		pwr_mgmt_ctrl = CS_TIM_MASK |
 744					PD_TIM_MASK | SR_TIM_MASK;
 
 745	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 746
 747	/* No CS_TIM in EMIF_4D5 */
 748	if (ip_rev == EMIF_4D5)
 749		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
 750
 751	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
 752
 753	return pwr_mgmt_ctrl;
 754}
 755
 756/*
 757 * Get the temperature level of the EMIF instance:
 758 * Reads the MR4 register of attached SDRAM parts to find out the temperature
 759 * level. If there are two parts attached(one on each CS), then the temperature
 760 * level for the EMIF instance is the higher of the two temperatures.
 761 */
 762static void get_temperature_level(struct emif_data *emif)
 763{
 764	u32		temp, temperature_level;
 765	void __iomem	*base;
 766
 767	base = emif->base;
 768
 769	/* Read mode register 4 */
 770	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
 771	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
 772	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
 773				MR4_SDRAM_REF_RATE_SHIFT;
 774
 775	if (emif->plat_data->device_info->cs1_used) {
 776		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
 777		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
 778		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
 779				>> MR4_SDRAM_REF_RATE_SHIFT;
 780		temperature_level = max(temp, temperature_level);
 781	}
 782
 783	/* treat everything less than nominal(3) in MR4 as nominal */
 784	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
 785		temperature_level = SDRAM_TEMP_NOMINAL;
 786
 787	/* if we get reserved value in MR4 persist with the existing value */
 788	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
 789		emif->temperature_level = temperature_level;
 790}
 791
 792/*
 793 * Program EMIF shadow registers that are not dependent on temperature
 794 * or voltage
 795 */
 796static void setup_registers(struct emif_data *emif, struct emif_regs *regs)
 797{
 798	void __iomem	*base = emif->base;
 799
 800	writel(regs->sdram_tim2_shdw, base + EMIF_SDRAM_TIMING_2_SHDW);
 801	writel(regs->phy_ctrl_1_shdw, base + EMIF_DDR_PHY_CTRL_1_SHDW);
 802
 803	/* Settings specific for EMIF4D5 */
 804	if (emif->plat_data->ip_rev != EMIF_4D5)
 805		return;
 806	writel(regs->ext_phy_ctrl_2_shdw, base + EMIF_EXT_PHY_CTRL_2_SHDW);
 807	writel(regs->ext_phy_ctrl_3_shdw, base + EMIF_EXT_PHY_CTRL_3_SHDW);
 808	writel(regs->ext_phy_ctrl_4_shdw, base + EMIF_EXT_PHY_CTRL_4_SHDW);
 809}
 810
 811/*
 812 * When voltage ramps dll calibration and forced read idle should
 813 * happen more often
 814 */
 815static void setup_volt_sensitive_regs(struct emif_data *emif,
 816		struct emif_regs *regs, u32 volt_state)
 817{
 818	u32		calib_ctrl;
 819	void __iomem	*base = emif->base;
 820
 821	/*
 822	 * EMIF_READ_IDLE_CTRL in EMIF4D refers to the same register as
 823	 * EMIF_DLL_CALIB_CTRL in EMIF4D5 and dll_calib_ctrl_shadow_*
 824	 * is an alias of the respective read_idle_ctrl_shdw_* (members of
 825	 * a union). So, the below code takes care of both cases
 826	 */
 827	if (volt_state == DDR_VOLTAGE_RAMPING)
 828		calib_ctrl = regs->dll_calib_ctrl_shdw_volt_ramp;
 829	else
 830		calib_ctrl = regs->dll_calib_ctrl_shdw_normal;
 831
 832	writel(calib_ctrl, base + EMIF_DLL_CALIB_CTRL_SHDW);
 833}
 834
 835/*
 836 * setup_temperature_sensitive_regs() - set the timings for temperature
 837 * sensitive registers. This happens once at initialisation time based
 838 * on the temperature at boot time and subsequently based on the temperature
 839 * alert interrupt. Temperature alert can happen when the temperature
 840 * increases or drops. So this function can have the effect of either
 841 * derating the timings or going back to nominal values.
 842 */
 843static void setup_temperature_sensitive_regs(struct emif_data *emif,
 844		struct emif_regs *regs)
 845{
 846	u32		tim1, tim3, ref_ctrl, type;
 847	void __iomem	*base = emif->base;
 848	u32		temperature;
 849
 850	type = emif->plat_data->device_info->type;
 851
 852	tim1 = regs->sdram_tim1_shdw;
 853	tim3 = regs->sdram_tim3_shdw;
 854	ref_ctrl = regs->ref_ctrl_shdw;
 855
 856	/* No de-rating for non-lpddr2 devices */
 857	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
 858		goto out;
 859
 860	temperature = emif->temperature_level;
 861	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
 862		ref_ctrl = regs->ref_ctrl_shdw_derated;
 863	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
 864		tim1 = regs->sdram_tim1_shdw_derated;
 865		tim3 = regs->sdram_tim3_shdw_derated;
 866		ref_ctrl = regs->ref_ctrl_shdw_derated;
 867	}
 868
 869out:
 870	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
 871	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
 872	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
 873}
 874
 875static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
 876{
 877	u32		old_temp_level;
 878	irqreturn_t	ret = IRQ_HANDLED;
 
 879
 880	spin_lock_irqsave(&emif_lock, irq_state);
 881	old_temp_level = emif->temperature_level;
 882	get_temperature_level(emif);
 883
 884	if (unlikely(emif->temperature_level == old_temp_level)) {
 885		goto out;
 886	} else if (!emif->curr_regs) {
 887		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
 888		goto out;
 889	}
 890
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 891	if (emif->temperature_level < old_temp_level ||
 892		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
 893		/*
 894		 * Temperature coming down - defer handling to thread OR
 895		 * Temperature far too high - do kernel_power_off() from
 896		 * thread context
 897		 */
 898		ret = IRQ_WAKE_THREAD;
 899	} else {
 900		/* Temperature is going up - handle immediately */
 901		setup_temperature_sensitive_regs(emif, emif->curr_regs);
 902		do_freq_update();
 903	}
 904
 905out:
 906	spin_unlock_irqrestore(&emif_lock, irq_state);
 907	return ret;
 908}
 909
 910static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
 911{
 912	u32			interrupts;
 913	struct emif_data	*emif = dev_id;
 914	void __iomem		*base = emif->base;
 915	struct device		*dev = emif->dev;
 916	irqreturn_t		ret = IRQ_HANDLED;
 917
 918	/* Save the status and clear it */
 919	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
 920	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
 921
 922	/*
 923	 * Handle temperature alert
 924	 * Temperature alert should be same for all ports
 925	 * So, it's enough to process it only for one of the ports
 926	 */
 927	if (interrupts & TA_SYS_MASK)
 928		ret = handle_temp_alert(base, emif);
 929
 930	if (interrupts & ERR_SYS_MASK)
 931		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
 932
 933	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
 934		/* Save the status and clear it */
 935		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
 936		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
 937
 938		if (interrupts & ERR_LL_MASK)
 939			dev_err(dev, "Access error from LL port - %x\n",
 940				interrupts);
 941	}
 942
 943	return ret;
 944}
 945
 946static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
 947{
 948	struct emif_data	*emif = dev_id;
 949
 950	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
 951		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
 952		kernel_power_off();
 
 
 
 
 
 
 
 953		return IRQ_HANDLED;
 954	}
 955
 956	spin_lock_irqsave(&emif_lock, irq_state);
 957
 958	if (emif->curr_regs) {
 959		setup_temperature_sensitive_regs(emif, emif->curr_regs);
 960		do_freq_update();
 961	} else {
 962		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
 963	}
 964
 965	spin_unlock_irqrestore(&emif_lock, irq_state);
 966
 967	return IRQ_HANDLED;
 968}
 969
 970static void clear_all_interrupts(struct emif_data *emif)
 971{
 972	void __iomem	*base = emif->base;
 973
 974	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
 975		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
 976	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
 977		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
 978			base + EMIF_LL_OCP_INTERRUPT_STATUS);
 979}
 980
 981static void disable_and_clear_all_interrupts(struct emif_data *emif)
 982{
 983	void __iomem		*base = emif->base;
 984
 985	/* Disable all interrupts */
 986	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
 987		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
 988	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
 989		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
 990			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
 991
 992	/* Clear all interrupts */
 993	clear_all_interrupts(emif);
 994}
 995
 996static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
 997{
 998	u32		interrupts, type;
 999	void __iomem	*base = emif->base;
1000
1001	type = emif->plat_data->device_info->type;
1002
1003	clear_all_interrupts(emif);
1004
1005	/* Enable interrupts for SYS interface */
1006	interrupts = EN_ERR_SYS_MASK;
1007	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
1008		interrupts |= EN_TA_SYS_MASK;
1009	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
1010
1011	/* Enable interrupts for LL interface */
1012	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1013		/* TA need not be enabled for LL */
1014		interrupts = EN_ERR_LL_MASK;
1015		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
1016	}
1017
1018	/* setup IRQ handlers */
1019	return devm_request_threaded_irq(emif->dev, irq,
1020				    emif_interrupt_handler,
1021				    emif_threaded_isr,
1022				    0, dev_name(emif->dev),
1023				    emif);
1024
1025}
1026
1027static void __init_or_module emif_onetime_settings(struct emif_data *emif)
1028{
1029	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
1030	void __iomem			*base = emif->base;
1031	const struct lpddr2_addressing	*addressing;
1032	const struct ddr_device_info	*device_info;
1033
1034	device_info = emif->plat_data->device_info;
1035	addressing = get_addressing_table(device_info);
1036
1037	/*
1038	 * Init power management settings
1039	 * We don't know the frequency yet. Use a high frequency
1040	 * value for a conservative timeout setting
1041	 */
1042	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
1043			emif->plat_data->ip_rev);
1044	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
1045	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
1046
1047	/* Init ZQ calibration settings */
1048	zq = get_zq_config_reg(addressing, device_info->cs1_used,
1049		device_info->cal_resistors_per_cs);
1050	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
1051
1052	/* Check temperature level temperature level*/
1053	get_temperature_level(emif);
1054	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
1055		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1056
1057	/* Init temperature polling */
1058	temp_alert_cfg = get_temp_alert_config(addressing,
1059		emif->plat_data->custom_configs, device_info->cs1_used,
1060		device_info->io_width, get_emif_bus_width(emif));
1061	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
1062
1063	/*
1064	 * Program external PHY control registers that are not frequency
1065	 * dependent
1066	 */
1067	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
1068		return;
1069	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
1070	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
1071	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
1072	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
1073	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
1074	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
1075	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
1076	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
1077	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
1078	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
1079	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
1080	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
1081	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
1082	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
1083	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
1084	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
1085	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
1086	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
1087	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
1088	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
1089	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
1090}
1091
1092static void get_default_timings(struct emif_data *emif)
1093{
1094	struct emif_platform_data *pd = emif->plat_data;
1095
1096	pd->timings		= lpddr2_jedec_timings;
1097	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
1098
1099	dev_warn(emif->dev, "%s: using default timings\n", __func__);
1100}
1101
1102static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
1103		u32 ip_rev, struct device *dev)
1104{
1105	int valid;
1106
1107	valid = (type == DDR_TYPE_LPDDR2_S4 ||
1108			type == DDR_TYPE_LPDDR2_S2)
1109		&& (density >= DDR_DENSITY_64Mb
1110			&& density <= DDR_DENSITY_8Gb)
1111		&& (io_width >= DDR_IO_WIDTH_8
1112			&& io_width <= DDR_IO_WIDTH_32);
1113
1114	/* Combinations of EMIF and PHY revisions that we support today */
1115	switch (ip_rev) {
1116	case EMIF_4D:
1117		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
1118		break;
1119	case EMIF_4D5:
1120		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
1121		break;
1122	default:
1123		valid = 0;
1124	}
1125
1126	if (!valid)
1127		dev_err(dev, "%s: invalid DDR details\n", __func__);
1128	return valid;
1129}
1130
1131static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
1132		struct device *dev)
1133{
1134	int valid = 1;
1135
1136	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
1137		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
1138		valid = cust_cfgs->lpmode_freq_threshold &&
1139			cust_cfgs->lpmode_timeout_performance &&
1140			cust_cfgs->lpmode_timeout_power;
1141
1142	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
1143		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
1144
1145	if (!valid)
1146		dev_warn(dev, "%s: invalid custom configs\n", __func__);
1147
1148	return valid;
1149}
1150
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1151static struct emif_data *__init_or_module get_device_details(
1152		struct platform_device *pdev)
1153{
1154	u32				size;
1155	struct emif_data		*emif = NULL;
1156	struct ddr_device_info		*dev_info;
1157	struct emif_custom_configs	*cust_cfgs;
1158	struct emif_platform_data	*pd;
1159	struct device			*dev;
1160	void				*temp;
1161
1162	pd = pdev->dev.platform_data;
1163	dev = &pdev->dev;
1164
1165	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
1166			pd->device_info->density, pd->device_info->io_width,
1167			pd->phy_type, pd->ip_rev, dev))) {
1168		dev_err(dev, "%s: invalid device data\n", __func__);
1169		goto error;
1170	}
1171
1172	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1173	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1174	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1175
1176	if (!emif || !pd || !dev_info) {
1177		dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__);
1178		goto error;
1179	}
1180
1181	memcpy(temp, pd, sizeof(*pd));
1182	pd = temp;
1183	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1184
1185	pd->device_info		= dev_info;
1186	emif->plat_data		= pd;
1187	emif->dev		= dev;
1188	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1189
1190	/*
1191	 * For EMIF instances other than EMIF1 see if the devices connected
1192	 * are exactly same as on EMIF1(which is typically the case). If so,
1193	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1194	 * This will save some memory and some computation later.
1195	 */
1196	emif->duplicate = emif1 && (memcmp(dev_info,
1197		emif1->plat_data->device_info,
1198		sizeof(struct ddr_device_info)) == 0);
1199
1200	if (emif->duplicate) {
1201		pd->timings = NULL;
1202		pd->min_tck = NULL;
1203		goto out;
1204	} else if (emif1) {
1205		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1206			__func__);
1207	}
1208
1209	/*
1210	 * Copy custom configs - ignore allocation error, if any, as
1211	 * custom_configs is not very critical
1212	 */
1213	cust_cfgs = pd->custom_configs;
1214	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1215		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1216		if (temp)
1217			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
1218		else
1219			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1220				__LINE__);
1221		pd->custom_configs = temp;
1222	}
1223
1224	/*
1225	 * Copy timings and min-tck values from platform data. If it is not
1226	 * available or if memory allocation fails, use JEDEC defaults
1227	 */
1228	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1229	if (pd->timings) {
1230		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1231		if (temp) {
1232			memcpy(temp, pd->timings, sizeof(*pd->timings));
1233			pd->timings = temp;
1234		} else {
1235			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1236				__LINE__);
1237			get_default_timings(emif);
1238		}
1239	} else {
1240		get_default_timings(emif);
1241	}
1242
1243	if (pd->min_tck) {
1244		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1245		if (temp) {
1246			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1247			pd->min_tck = temp;
1248		} else {
1249			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1250				__LINE__);
1251			pd->min_tck = &lpddr2_jedec_min_tck;
1252		}
1253	} else {
1254		pd->min_tck = &lpddr2_jedec_min_tck;
1255	}
1256
1257out:
1258	return emif;
1259
1260error:
1261	return NULL;
1262}
1263
1264static int __init_or_module emif_probe(struct platform_device *pdev)
1265{
1266	struct emif_data	*emif;
1267	struct resource		*res;
1268	int			irq;
 
 
 
 
1269
1270	emif = get_device_details(pdev);
1271	if (!emif) {
1272		pr_err("%s: error getting device data\n", __func__);
1273		goto error;
1274	}
1275
1276	list_add(&emif->node, &device_list);
1277	emif->addressing = get_addressing_table(emif->plat_data->device_info);
1278
1279	/* Save pointers to each other in emif and device structures */
1280	emif->dev = &pdev->dev;
1281	platform_set_drvdata(pdev, emif);
1282
1283	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1284	if (!res) {
1285		dev_err(emif->dev, "%s: error getting memory resource\n",
1286			__func__);
1287		goto error;
1288	}
1289
1290	emif->base = devm_request_and_ioremap(emif->dev, res);
1291	if (!emif->base) {
1292		dev_err(emif->dev, "%s: devm_request_and_ioremap() failed\n",
1293			__func__);
1294		goto error;
1295	}
1296
1297	irq = platform_get_irq(pdev, 0);
1298	if (irq < 0) {
1299		dev_err(emif->dev, "%s: error getting IRQ resource - %d\n",
1300			__func__, irq);
1301		goto error;
1302	}
1303
1304	emif_onetime_settings(emif);
1305	emif_debugfs_init(emif);
1306	disable_and_clear_all_interrupts(emif);
1307	setup_interrupts(emif, irq);
 
 
1308
1309	/* One-time actions taken on probing the first device */
1310	if (!emif1) {
1311		emif1 = emif;
1312		spin_lock_init(&emif_lock);
1313
1314		/*
1315		 * TODO: register notifiers for frequency and voltage
1316		 * change here once the respective frameworks are
1317		 * available
1318		 */
1319	}
1320
1321	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1322		__func__, emif->base, irq);
1323
1324	return 0;
1325error:
1326	return -ENODEV;
1327}
1328
1329static int __exit emif_remove(struct platform_device *pdev)
1330{
1331	struct emif_data *emif = platform_get_drvdata(pdev);
1332
1333	emif_debugfs_exit(emif);
1334
1335	return 0;
1336}
1337
1338static void emif_shutdown(struct platform_device *pdev)
1339{
1340	struct emif_data	*emif = platform_get_drvdata(pdev);
1341
1342	disable_and_clear_all_interrupts(emif);
1343}
1344
1345static int get_emif_reg_values(struct emif_data *emif, u32 freq,
1346		struct emif_regs *regs)
1347{
1348	u32				cs1_used, ip_rev, phy_type;
1349	u32				cl, type;
1350	const struct lpddr2_timings	*timings;
1351	const struct lpddr2_min_tck	*min_tck;
1352	const struct ddr_device_info	*device_info;
1353	const struct lpddr2_addressing	*addressing;
1354	struct emif_data		*emif_for_calc;
1355	struct device			*dev;
1356	const struct emif_custom_configs *custom_configs;
1357
1358	dev = emif->dev;
1359	/*
1360	 * If the devices on this EMIF instance is duplicate of EMIF1,
1361	 * use EMIF1 details for the calculation
1362	 */
1363	emif_for_calc	= emif->duplicate ? emif1 : emif;
1364	timings		= get_timings_table(emif_for_calc, freq);
1365	addressing	= emif_for_calc->addressing;
1366	if (!timings || !addressing) {
1367		dev_err(dev, "%s: not enough data available for %dHz",
1368			__func__, freq);
1369		return -1;
1370	}
1371
1372	device_info	= emif_for_calc->plat_data->device_info;
1373	type		= device_info->type;
1374	cs1_used	= device_info->cs1_used;
1375	ip_rev		= emif_for_calc->plat_data->ip_rev;
1376	phy_type	= emif_for_calc->plat_data->phy_type;
1377
1378	min_tck		= emif_for_calc->plat_data->min_tck;
1379	custom_configs	= emif_for_calc->plat_data->custom_configs;
1380
1381	set_ddr_clk_period(freq);
1382
1383	regs->ref_ctrl_shdw = get_sdram_ref_ctrl_shdw(freq, addressing);
1384	regs->sdram_tim1_shdw = get_sdram_tim_1_shdw(timings, min_tck,
1385			addressing);
1386	regs->sdram_tim2_shdw = get_sdram_tim_2_shdw(timings, min_tck,
1387			addressing, type);
1388	regs->sdram_tim3_shdw = get_sdram_tim_3_shdw(timings, min_tck,
1389		addressing, type, ip_rev, EMIF_NORMAL_TIMINGS);
1390
1391	cl = get_cl(emif);
1392
1393	if (phy_type == EMIF_PHY_TYPE_ATTILAPHY && ip_rev == EMIF_4D) {
1394		regs->phy_ctrl_1_shdw = get_ddr_phy_ctrl_1_attilaphy_4d(
1395			timings, freq, cl);
1396	} else if (phy_type == EMIF_PHY_TYPE_INTELLIPHY && ip_rev == EMIF_4D5) {
1397		regs->phy_ctrl_1_shdw = get_phy_ctrl_1_intelliphy_4d5(freq, cl);
1398		regs->ext_phy_ctrl_2_shdw = get_ext_phy_ctrl_2_intelliphy_4d5();
1399		regs->ext_phy_ctrl_3_shdw = get_ext_phy_ctrl_3_intelliphy_4d5();
1400		regs->ext_phy_ctrl_4_shdw = get_ext_phy_ctrl_4_intelliphy_4d5();
1401	} else {
1402		return -1;
1403	}
1404
1405	/* Only timeout values in pwr_mgmt_ctrl_shdw register */
1406	regs->pwr_mgmt_ctrl_shdw =
1407		get_pwr_mgmt_ctrl(freq, emif_for_calc, ip_rev) &
1408		(CS_TIM_MASK | SR_TIM_MASK | PD_TIM_MASK);
1409
1410	if (ip_rev & EMIF_4D) {
1411		regs->read_idle_ctrl_shdw_normal =
1412			get_read_idle_ctrl_shdw(DDR_VOLTAGE_STABLE);
1413
1414		regs->read_idle_ctrl_shdw_volt_ramp =
1415			get_read_idle_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1416	} else if (ip_rev & EMIF_4D5) {
1417		regs->dll_calib_ctrl_shdw_normal =
1418			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_STABLE);
1419
1420		regs->dll_calib_ctrl_shdw_volt_ramp =
1421			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1422	}
1423
1424	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
1425		regs->ref_ctrl_shdw_derated = get_sdram_ref_ctrl_shdw(freq / 4,
1426			addressing);
1427
1428		regs->sdram_tim1_shdw_derated =
1429			get_sdram_tim_1_shdw_derated(timings, min_tck,
1430				addressing);
1431
1432		regs->sdram_tim3_shdw_derated = get_sdram_tim_3_shdw(timings,
1433			min_tck, addressing, type, ip_rev,
1434			EMIF_DERATED_TIMINGS);
1435	}
1436
1437	regs->freq = freq;
1438
1439	return 0;
1440}
1441
1442/*
1443 * get_regs() - gets the cached emif_regs structure for a given EMIF instance
1444 * given frequency(freq):
1445 *
1446 * As an optimisation, every EMIF instance other than EMIF1 shares the
1447 * register cache with EMIF1 if the devices connected on this instance
1448 * are same as that on EMIF1(indicated by the duplicate flag)
1449 *
1450 * If we do not have an entry corresponding to the frequency given, we
1451 * allocate a new entry and calculate the values
1452 *
1453 * Upon finding the right reg dump, save it in curr_regs. It can be
1454 * directly used for thermal de-rating and voltage ramping changes.
1455 */
1456static struct emif_regs *get_regs(struct emif_data *emif, u32 freq)
1457{
1458	int			i;
1459	struct emif_regs	**regs_cache;
1460	struct emif_regs	*regs = NULL;
1461	struct device		*dev;
1462
1463	dev = emif->dev;
1464	if (emif->curr_regs && emif->curr_regs->freq == freq) {
1465		dev_dbg(dev, "%s: using curr_regs - %u Hz", __func__, freq);
1466		return emif->curr_regs;
1467	}
1468
1469	if (emif->duplicate)
1470		regs_cache = emif1->regs_cache;
1471	else
1472		regs_cache = emif->regs_cache;
1473
1474	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
1475		if (regs_cache[i]->freq == freq) {
1476			regs = regs_cache[i];
1477			dev_dbg(dev,
1478				"%s: reg dump found in reg cache for %u Hz\n",
1479				__func__, freq);
1480			break;
1481		}
1482	}
1483
1484	/*
1485	 * If we don't have an entry for this frequency in the cache create one
1486	 * and calculate the values
1487	 */
1488	if (!regs) {
1489		regs = devm_kzalloc(emif->dev, sizeof(*regs), GFP_ATOMIC);
1490		if (!regs)
1491			return NULL;
1492
1493		if (get_emif_reg_values(emif, freq, regs)) {
1494			devm_kfree(emif->dev, regs);
1495			return NULL;
1496		}
1497
1498		/*
1499		 * Now look for an un-used entry in the cache and save the
1500		 * newly created struct. If there are no free entries
1501		 * over-write the last entry
1502		 */
1503		for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++)
1504			;
1505
1506		if (i >= EMIF_MAX_NUM_FREQUENCIES) {
1507			dev_warn(dev, "%s: regs_cache full - reusing a slot!!\n",
1508				__func__);
1509			i = EMIF_MAX_NUM_FREQUENCIES - 1;
1510			devm_kfree(emif->dev, regs_cache[i]);
1511		}
1512		regs_cache[i] = regs;
1513	}
1514
1515	return regs;
1516}
1517
1518static void do_volt_notify_handling(struct emif_data *emif, u32 volt_state)
1519{
1520	dev_dbg(emif->dev, "%s: voltage notification : %d", __func__,
1521		volt_state);
1522
1523	if (!emif->curr_regs) {
1524		dev_err(emif->dev,
1525			"%s: volt-notify before registers are ready: %d\n",
1526			__func__, volt_state);
1527		return;
1528	}
1529
1530	setup_volt_sensitive_regs(emif, emif->curr_regs, volt_state);
1531}
1532
1533/*
1534 * TODO: voltage notify handling should be hooked up to
1535 * regulator framework as soon as the necessary support
1536 * is available in mainline kernel. This function is un-used
1537 * right now.
1538 */
1539static void __attribute__((unused)) volt_notify_handling(u32 volt_state)
1540{
1541	struct emif_data *emif;
1542
1543	spin_lock_irqsave(&emif_lock, irq_state);
1544
1545	list_for_each_entry(emif, &device_list, node)
1546		do_volt_notify_handling(emif, volt_state);
1547	do_freq_update();
1548
1549	spin_unlock_irqrestore(&emif_lock, irq_state);
1550}
1551
1552static void do_freq_pre_notify_handling(struct emif_data *emif, u32 new_freq)
1553{
1554	struct emif_regs *regs;
1555
1556	regs = get_regs(emif, new_freq);
1557	if (!regs)
1558		return;
1559
1560	emif->curr_regs = regs;
1561
1562	/*
1563	 * Update the shadow registers:
1564	 * Temperature and voltage-ramp sensitive settings are also configured
1565	 * in terms of DDR cycles. So, we need to update them too when there
1566	 * is a freq change
1567	 */
1568	dev_dbg(emif->dev, "%s: setting up shadow registers for %uHz",
1569		__func__, new_freq);
1570	setup_registers(emif, regs);
1571	setup_temperature_sensitive_regs(emif, regs);
1572	setup_volt_sensitive_regs(emif, regs, DDR_VOLTAGE_STABLE);
1573
1574	/*
1575	 * Part of workaround for errata i728. See do_freq_update()
1576	 * for more details
1577	 */
1578	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1579		set_lpmode(emif, EMIF_LP_MODE_DISABLE);
1580}
1581
1582/*
1583 * TODO: frequency notify handling should be hooked up to
1584 * clock framework as soon as the necessary support is
1585 * available in mainline kernel. This function is un-used
1586 * right now.
1587 */
1588static void __attribute__((unused)) freq_pre_notify_handling(u32 new_freq)
1589{
1590	struct emif_data *emif;
1591
1592	/*
1593	 * NOTE: we are taking the spin-lock here and releases it
1594	 * only in post-notifier. This doesn't look good and
1595	 * Sparse complains about it, but this seems to be
1596	 * un-avoidable. We need to lock a sequence of events
1597	 * that is split between EMIF and clock framework.
1598	 *
1599	 * 1. EMIF driver updates EMIF timings in shadow registers in the
1600	 *    frequency pre-notify callback from clock framework
1601	 * 2. clock framework sets up the registers for the new frequency
1602	 * 3. clock framework initiates a hw-sequence that updates
1603	 *    the frequency EMIF timings synchronously.
1604	 *
1605	 * All these 3 steps should be performed as an atomic operation
1606	 * vis-a-vis similar sequence in the EMIF interrupt handler
1607	 * for temperature events. Otherwise, there could be race
1608	 * conditions that could result in incorrect EMIF timings for
1609	 * a given frequency
1610	 */
1611	spin_lock_irqsave(&emif_lock, irq_state);
1612
1613	list_for_each_entry(emif, &device_list, node)
1614		do_freq_pre_notify_handling(emif, new_freq);
1615}
1616
1617static void do_freq_post_notify_handling(struct emif_data *emif)
1618{
1619	/*
1620	 * Part of workaround for errata i728. See do_freq_update()
1621	 * for more details
1622	 */
1623	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1624		set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
1625}
1626
1627/*
1628 * TODO: frequency notify handling should be hooked up to
1629 * clock framework as soon as the necessary support is
1630 * available in mainline kernel. This function is un-used
1631 * right now.
1632 */
1633static void __attribute__((unused)) freq_post_notify_handling(void)
1634{
1635	struct emif_data *emif;
1636
1637	list_for_each_entry(emif, &device_list, node)
1638		do_freq_post_notify_handling(emif);
1639
1640	/*
1641	 * Lock is done in pre-notify handler. See freq_pre_notify_handling()
1642	 * for more details
1643	 */
1644	spin_unlock_irqrestore(&emif_lock, irq_state);
1645}
1646
1647static struct platform_driver emif_driver = {
1648	.remove		= __exit_p(emif_remove),
1649	.shutdown	= emif_shutdown,
1650	.driver = {
1651		.name = "emif",
 
1652	},
1653};
1654
1655static int __init_or_module emif_register(void)
1656{
1657	return platform_driver_probe(&emif_driver, emif_probe);
1658}
1659
1660static void __exit emif_unregister(void)
1661{
1662	platform_driver_unregister(&emif_driver);
1663}
1664
1665module_init(emif_register);
1666module_exit(emif_unregister);
1667MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1668MODULE_LICENSE("GPL");
1669MODULE_ALIAS("platform:emif");
1670MODULE_AUTHOR("Texas Instruments Inc");