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   1/*
   2 * Amlogic SD/eMMC driver for the GX/S905 family SoCs
   3 *
   4 * Copyright (c) 2016 BayLibre, SAS.
   5 * Author: Kevin Hilman <khilman@baylibre.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of version 2 of the GNU General Public License as
   9 * published by the Free Software Foundation.
  10 *
  11 * This program is distributed in the hope that it will be useful, but
  12 * WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 * The full GNU General Public License is included in this distribution
  19 * in the file called COPYING.
  20 */
  21#include <linux/kernel.h>
  22#include <linux/module.h>
  23#include <linux/init.h>
  24#include <linux/device.h>
  25#include <linux/of_device.h>
  26#include <linux/platform_device.h>
  27#include <linux/ioport.h>
  28#include <linux/spinlock.h>
  29#include <linux/dma-mapping.h>
  30#include <linux/mmc/host.h>
  31#include <linux/mmc/mmc.h>
  32#include <linux/mmc/sdio.h>
  33#include <linux/mmc/slot-gpio.h>
  34#include <linux/io.h>
  35#include <linux/clk.h>
  36#include <linux/clk-provider.h>
  37#include <linux/regulator/consumer.h>
  38#include <linux/interrupt.h>
  39#include <linux/bitfield.h>
  40#include <linux/pinctrl/consumer.h>
  41
  42#define DRIVER_NAME "meson-gx-mmc"
  43
  44#define SD_EMMC_CLOCK 0x0
  45#define   CLK_DIV_MASK GENMASK(5, 0)
  46#define   CLK_SRC_MASK GENMASK(7, 6)
  47#define   CLK_CORE_PHASE_MASK GENMASK(9, 8)
  48#define   CLK_TX_PHASE_MASK GENMASK(11, 10)
  49#define   CLK_RX_PHASE_MASK GENMASK(13, 12)
  50#define   CLK_TX_DELAY_MASK GENMASK(19, 16)
  51#define   CLK_RX_DELAY_MASK GENMASK(23, 20)
  52#define   CLK_DELAY_STEP_PS 200
  53#define   CLK_PHASE_STEP 30
  54#define   CLK_PHASE_POINT_NUM (360 / CLK_PHASE_STEP)
  55#define   CLK_ALWAYS_ON BIT(24)
  56
  57#define SD_EMMC_DELAY 0x4
  58#define SD_EMMC_ADJUST 0x8
  59#define SD_EMMC_CALOUT 0x10
  60#define SD_EMMC_START 0x40
  61#define   START_DESC_INIT BIT(0)
  62#define   START_DESC_BUSY BIT(1)
  63#define   START_DESC_ADDR_MASK GENMASK(31, 2)
  64
  65#define SD_EMMC_CFG 0x44
  66#define   CFG_BUS_WIDTH_MASK GENMASK(1, 0)
  67#define   CFG_BUS_WIDTH_1 0x0
  68#define   CFG_BUS_WIDTH_4 0x1
  69#define   CFG_BUS_WIDTH_8 0x2
  70#define   CFG_DDR BIT(2)
  71#define   CFG_BLK_LEN_MASK GENMASK(7, 4)
  72#define   CFG_RESP_TIMEOUT_MASK GENMASK(11, 8)
  73#define   CFG_RC_CC_MASK GENMASK(15, 12)
  74#define   CFG_STOP_CLOCK BIT(22)
  75#define   CFG_CLK_ALWAYS_ON BIT(18)
  76#define   CFG_CHK_DS BIT(20)
  77#define   CFG_AUTO_CLK BIT(23)
  78
  79#define SD_EMMC_STATUS 0x48
  80#define   STATUS_BUSY BIT(31)
  81#define   STATUS_DATI GENMASK(23, 16)
  82
  83#define SD_EMMC_IRQ_EN 0x4c
  84#define   IRQ_RXD_ERR_MASK GENMASK(7, 0)
  85#define   IRQ_TXD_ERR BIT(8)
  86#define   IRQ_DESC_ERR BIT(9)
  87#define   IRQ_RESP_ERR BIT(10)
  88#define   IRQ_CRC_ERR \
  89	(IRQ_RXD_ERR_MASK | IRQ_TXD_ERR | IRQ_DESC_ERR | IRQ_RESP_ERR)
  90#define   IRQ_RESP_TIMEOUT BIT(11)
  91#define   IRQ_DESC_TIMEOUT BIT(12)
  92#define   IRQ_TIMEOUTS \
  93	(IRQ_RESP_TIMEOUT | IRQ_DESC_TIMEOUT)
  94#define   IRQ_END_OF_CHAIN BIT(13)
  95#define   IRQ_RESP_STATUS BIT(14)
  96#define   IRQ_SDIO BIT(15)
  97#define   IRQ_EN_MASK \
  98	(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN | IRQ_RESP_STATUS |\
  99	 IRQ_SDIO)
 100
 101#define SD_EMMC_CMD_CFG 0x50
 102#define SD_EMMC_CMD_ARG 0x54
 103#define SD_EMMC_CMD_DAT 0x58
 104#define SD_EMMC_CMD_RSP 0x5c
 105#define SD_EMMC_CMD_RSP1 0x60
 106#define SD_EMMC_CMD_RSP2 0x64
 107#define SD_EMMC_CMD_RSP3 0x68
 108
 109#define SD_EMMC_RXD 0x94
 110#define SD_EMMC_TXD 0x94
 111#define SD_EMMC_LAST_REG SD_EMMC_TXD
 112
 113#define SD_EMMC_CFG_BLK_SIZE 512 /* internal buffer max: 512 bytes */
 114#define SD_EMMC_CFG_RESP_TIMEOUT 256 /* in clock cycles */
 115#define SD_EMMC_CMD_TIMEOUT 1024 /* in ms */
 116#define SD_EMMC_CMD_TIMEOUT_DATA 4096 /* in ms */
 117#define SD_EMMC_CFG_CMD_GAP 16 /* in clock cycles */
 118#define SD_EMMC_DESC_BUF_LEN PAGE_SIZE
 119
 120#define SD_EMMC_PRE_REQ_DONE BIT(0)
 121#define SD_EMMC_DESC_CHAIN_MODE BIT(1)
 122
 123#define MUX_CLK_NUM_PARENTS 2
 124
 125struct sd_emmc_desc {
 126	u32 cmd_cfg;
 127	u32 cmd_arg;
 128	u32 cmd_data;
 129	u32 cmd_resp;
 130};
 131
 132struct meson_host {
 133	struct	device		*dev;
 134	struct	mmc_host	*mmc;
 135	struct	mmc_command	*cmd;
 136
 137	spinlock_t lock;
 138	void __iomem *regs;
 139	struct clk *core_clk;
 140	struct clk *mmc_clk;
 141	struct clk *rx_clk;
 142	struct clk *tx_clk;
 143	unsigned long req_rate;
 144
 145	struct pinctrl *pinctrl;
 146	struct pinctrl_state *pins_default;
 147	struct pinctrl_state *pins_clk_gate;
 148
 149	unsigned int bounce_buf_size;
 150	void *bounce_buf;
 151	dma_addr_t bounce_dma_addr;
 152	struct sd_emmc_desc *descs;
 153	dma_addr_t descs_dma_addr;
 154
 155	bool vqmmc_enabled;
 156};
 157
 158#define CMD_CFG_LENGTH_MASK GENMASK(8, 0)
 159#define CMD_CFG_BLOCK_MODE BIT(9)
 160#define CMD_CFG_R1B BIT(10)
 161#define CMD_CFG_END_OF_CHAIN BIT(11)
 162#define CMD_CFG_TIMEOUT_MASK GENMASK(15, 12)
 163#define CMD_CFG_NO_RESP BIT(16)
 164#define CMD_CFG_NO_CMD BIT(17)
 165#define CMD_CFG_DATA_IO BIT(18)
 166#define CMD_CFG_DATA_WR BIT(19)
 167#define CMD_CFG_RESP_NOCRC BIT(20)
 168#define CMD_CFG_RESP_128 BIT(21)
 169#define CMD_CFG_RESP_NUM BIT(22)
 170#define CMD_CFG_DATA_NUM BIT(23)
 171#define CMD_CFG_CMD_INDEX_MASK GENMASK(29, 24)
 172#define CMD_CFG_ERROR BIT(30)
 173#define CMD_CFG_OWNER BIT(31)
 174
 175#define CMD_DATA_MASK GENMASK(31, 2)
 176#define CMD_DATA_BIG_ENDIAN BIT(1)
 177#define CMD_DATA_SRAM BIT(0)
 178#define CMD_RESP_MASK GENMASK(31, 1)
 179#define CMD_RESP_SRAM BIT(0)
 180
 181struct meson_mmc_phase {
 182	struct clk_hw hw;
 183	void __iomem *reg;
 184	unsigned long phase_mask;
 185	unsigned long delay_mask;
 186	unsigned int delay_step_ps;
 187};
 188
 189#define to_meson_mmc_phase(_hw) container_of(_hw, struct meson_mmc_phase, hw)
 190
 191static int meson_mmc_clk_get_phase(struct clk_hw *hw)
 192{
 193	struct meson_mmc_phase *mmc = to_meson_mmc_phase(hw);
 194	unsigned int phase_num = 1 <<  hweight_long(mmc->phase_mask);
 195	unsigned long period_ps, p, d;
 196		int degrees;
 197	u32 val;
 198
 199	val = readl(mmc->reg);
 200	p = (val & mmc->phase_mask) >> __ffs(mmc->phase_mask);
 201	degrees = p * 360 / phase_num;
 202
 203	if (mmc->delay_mask) {
 204		period_ps = DIV_ROUND_UP((unsigned long)NSEC_PER_SEC * 1000,
 205					 clk_get_rate(hw->clk));
 206		d = (val & mmc->delay_mask) >> __ffs(mmc->delay_mask);
 207		degrees += d * mmc->delay_step_ps * 360 / period_ps;
 208		degrees %= 360;
 209	}
 210
 211	return degrees;
 212}
 213
 214static void meson_mmc_apply_phase_delay(struct meson_mmc_phase *mmc,
 215					unsigned int phase,
 216					unsigned int delay)
 217{
 218	u32 val;
 219
 220	val = readl(mmc->reg);
 221	val &= ~mmc->phase_mask;
 222	val |= phase << __ffs(mmc->phase_mask);
 223
 224	if (mmc->delay_mask) {
 225		val &= ~mmc->delay_mask;
 226		val |= delay << __ffs(mmc->delay_mask);
 227	}
 228
 229	writel(val, mmc->reg);
 230}
 231
 232static int meson_mmc_clk_set_phase(struct clk_hw *hw, int degrees)
 233{
 234	struct meson_mmc_phase *mmc = to_meson_mmc_phase(hw);
 235	unsigned int phase_num = 1 <<  hweight_long(mmc->phase_mask);
 236	unsigned long period_ps, d = 0, r;
 237	uint64_t p;
 238
 239	p = degrees % 360;
 240
 241	if (!mmc->delay_mask) {
 242		p = DIV_ROUND_CLOSEST_ULL(p, 360 / phase_num);
 243	} else {
 244		period_ps = DIV_ROUND_UP((unsigned long)NSEC_PER_SEC * 1000,
 245					 clk_get_rate(hw->clk));
 246
 247		/* First compute the phase index (p), the remainder (r) is the
 248		 * part we'll try to acheive using the delays (d).
 249		 */
 250		r = do_div(p, 360 / phase_num);
 251		d = DIV_ROUND_CLOSEST(r * period_ps,
 252				      360 * mmc->delay_step_ps);
 253		d = min(d, mmc->delay_mask >> __ffs(mmc->delay_mask));
 254	}
 255
 256	meson_mmc_apply_phase_delay(mmc, p, d);
 257	return 0;
 258}
 259
 260static const struct clk_ops meson_mmc_clk_phase_ops = {
 261	.get_phase = meson_mmc_clk_get_phase,
 262	.set_phase = meson_mmc_clk_set_phase,
 263};
 264
 265static unsigned int meson_mmc_get_timeout_msecs(struct mmc_data *data)
 266{
 267	unsigned int timeout = data->timeout_ns / NSEC_PER_MSEC;
 268
 269	if (!timeout)
 270		return SD_EMMC_CMD_TIMEOUT_DATA;
 271
 272	timeout = roundup_pow_of_two(timeout);
 273
 274	return min(timeout, 32768U); /* max. 2^15 ms */
 275}
 276
 277static struct mmc_command *meson_mmc_get_next_command(struct mmc_command *cmd)
 278{
 279	if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
 280		return cmd->mrq->cmd;
 281	else if (mmc_op_multi(cmd->opcode) &&
 282		 (!cmd->mrq->sbc || cmd->error || cmd->data->error))
 283		return cmd->mrq->stop;
 284	else
 285		return NULL;
 286}
 287
 288static void meson_mmc_get_transfer_mode(struct mmc_host *mmc,
 289					struct mmc_request *mrq)
 290{
 291	struct mmc_data *data = mrq->data;
 292	struct scatterlist *sg;
 293	int i;
 294	bool use_desc_chain_mode = true;
 295
 296	/*
 297	 * Broken SDIO with AP6255-based WiFi on Khadas VIM Pro has been
 298	 * reported. For some strange reason this occurs in descriptor
 299	 * chain mode only. So let's fall back to bounce buffer mode
 300	 * for command SD_IO_RW_EXTENDED.
 301	 */
 302	if (mrq->cmd->opcode == SD_IO_RW_EXTENDED)
 303		return;
 304
 305	for_each_sg(data->sg, sg, data->sg_len, i)
 306		/* check for 8 byte alignment */
 307		if (sg->offset & 7) {
 308			WARN_ONCE(1, "unaligned scatterlist buffer\n");
 309			use_desc_chain_mode = false;
 310			break;
 311		}
 312
 313	if (use_desc_chain_mode)
 314		data->host_cookie |= SD_EMMC_DESC_CHAIN_MODE;
 315}
 316
 317static inline bool meson_mmc_desc_chain_mode(const struct mmc_data *data)
 318{
 319	return data->host_cookie & SD_EMMC_DESC_CHAIN_MODE;
 320}
 321
 322static inline bool meson_mmc_bounce_buf_read(const struct mmc_data *data)
 323{
 324	return data && data->flags & MMC_DATA_READ &&
 325	       !meson_mmc_desc_chain_mode(data);
 326}
 327
 328static void meson_mmc_pre_req(struct mmc_host *mmc, struct mmc_request *mrq)
 329{
 330	struct mmc_data *data = mrq->data;
 331
 332	if (!data)
 333		return;
 334
 335	meson_mmc_get_transfer_mode(mmc, mrq);
 336	data->host_cookie |= SD_EMMC_PRE_REQ_DONE;
 337
 338	if (!meson_mmc_desc_chain_mode(data))
 339		return;
 340
 341	data->sg_count = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
 342                                   mmc_get_dma_dir(data));
 343	if (!data->sg_count)
 344		dev_err(mmc_dev(mmc), "dma_map_sg failed");
 345}
 346
 347static void meson_mmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
 348			       int err)
 349{
 350	struct mmc_data *data = mrq->data;
 351
 352	if (data && meson_mmc_desc_chain_mode(data) && data->sg_count)
 353		dma_unmap_sg(mmc_dev(mmc), data->sg, data->sg_len,
 354			     mmc_get_dma_dir(data));
 355}
 356
 357static bool meson_mmc_timing_is_ddr(struct mmc_ios *ios)
 358{
 359	if (ios->timing == MMC_TIMING_MMC_DDR52 ||
 360	    ios->timing == MMC_TIMING_UHS_DDR50 ||
 361	    ios->timing == MMC_TIMING_MMC_HS400)
 362		return true;
 363
 364	return false;
 365}
 366
 367/*
 368 * Gating the clock on this controller is tricky.  It seems the mmc clock
 369 * is also used by the controller.  It may crash during some operation if the
 370 * clock is stopped.  The safest thing to do, whenever possible, is to keep
 371 * clock running at stop it at the pad using the pinmux.
 372 */
 373static void meson_mmc_clk_gate(struct meson_host *host)
 374{
 375	u32 cfg;
 376
 377	if (host->pins_clk_gate) {
 378		pinctrl_select_state(host->pinctrl, host->pins_clk_gate);
 379	} else {
 380		/*
 381		 * If the pinmux is not provided - default to the classic and
 382		 * unsafe method
 383		 */
 384		cfg = readl(host->regs + SD_EMMC_CFG);
 385		cfg |= CFG_STOP_CLOCK;
 386		writel(cfg, host->regs + SD_EMMC_CFG);
 387	}
 388}
 389
 390static void meson_mmc_clk_ungate(struct meson_host *host)
 391{
 392	u32 cfg;
 393
 394	if (host->pins_clk_gate)
 395		pinctrl_select_state(host->pinctrl, host->pins_default);
 396
 397	/* Make sure the clock is not stopped in the controller */
 398	cfg = readl(host->regs + SD_EMMC_CFG);
 399	cfg &= ~CFG_STOP_CLOCK;
 400	writel(cfg, host->regs + SD_EMMC_CFG);
 401}
 402
 403static int meson_mmc_clk_set(struct meson_host *host, struct mmc_ios *ios)
 404{
 405	struct mmc_host *mmc = host->mmc;
 406	unsigned long rate = ios->clock;
 407	int ret;
 408	u32 cfg;
 409
 410	/* DDR modes require higher module clock */
 411	if (meson_mmc_timing_is_ddr(ios))
 412		rate <<= 1;
 413
 414	/* Same request - bail-out */
 415	if (host->req_rate == rate)
 416		return 0;
 417
 418	/* stop clock */
 419	meson_mmc_clk_gate(host);
 420	host->req_rate = 0;
 421
 422	if (!rate) {
 423		mmc->actual_clock = 0;
 424		/* return with clock being stopped */
 425		return 0;
 426	}
 427
 428	/* Stop the clock during rate change to avoid glitches */
 429	cfg = readl(host->regs + SD_EMMC_CFG);
 430	cfg |= CFG_STOP_CLOCK;
 431	writel(cfg, host->regs + SD_EMMC_CFG);
 432
 433	ret = clk_set_rate(host->mmc_clk, rate);
 434	if (ret) {
 435		dev_err(host->dev, "Unable to set cfg_div_clk to %lu. ret=%d\n",
 436			rate, ret);
 437		return ret;
 438	}
 439
 440	host->req_rate = rate;
 441	mmc->actual_clock = clk_get_rate(host->mmc_clk);
 442
 443	/* We should report the real output frequency of the controller */
 444	if (meson_mmc_timing_is_ddr(ios))
 445		mmc->actual_clock >>= 1;
 446
 447	dev_dbg(host->dev, "clk rate: %u Hz\n", mmc->actual_clock);
 448	if (ios->clock != mmc->actual_clock)
 449		dev_dbg(host->dev, "requested rate was %u\n", ios->clock);
 450
 451	/* (re)start clock */
 452	meson_mmc_clk_ungate(host);
 453
 454	return 0;
 455}
 456
 457/*
 458 * The SD/eMMC IP block has an internal mux and divider used for
 459 * generating the MMC clock.  Use the clock framework to create and
 460 * manage these clocks.
 461 */
 462static int meson_mmc_clk_init(struct meson_host *host)
 463{
 464	struct clk_init_data init;
 465	struct clk_mux *mux;
 466	struct clk_divider *div;
 467	struct meson_mmc_phase *core, *tx, *rx;
 468	struct clk *clk;
 469	char clk_name[32];
 470	int i, ret = 0;
 471	const char *mux_parent_names[MUX_CLK_NUM_PARENTS];
 472	const char *clk_parent[1];
 473	u32 clk_reg;
 474
 475	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
 476	clk_reg = 0;
 477	clk_reg |= CLK_ALWAYS_ON;
 478	clk_reg |= CLK_DIV_MASK;
 479	writel(clk_reg, host->regs + SD_EMMC_CLOCK);
 480
 481	/* get the mux parents */
 482	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
 483		struct clk *clk;
 484		char name[16];
 485
 486		snprintf(name, sizeof(name), "clkin%d", i);
 487		clk = devm_clk_get(host->dev, name);
 488		if (IS_ERR(clk)) {
 489			if (clk != ERR_PTR(-EPROBE_DEFER))
 490				dev_err(host->dev, "Missing clock %s\n", name);
 491			return PTR_ERR(clk);
 492		}
 493
 494		mux_parent_names[i] = __clk_get_name(clk);
 495	}
 496
 497	/* create the mux */
 498	mux = devm_kzalloc(host->dev, sizeof(*mux), GFP_KERNEL);
 499	if (!mux)
 500		return -ENOMEM;
 501
 502	snprintf(clk_name, sizeof(clk_name), "%s#mux", dev_name(host->dev));
 503	init.name = clk_name;
 504	init.ops = &clk_mux_ops;
 505	init.flags = 0;
 506	init.parent_names = mux_parent_names;
 507	init.num_parents = MUX_CLK_NUM_PARENTS;
 508
 509	mux->reg = host->regs + SD_EMMC_CLOCK;
 510	mux->shift = __ffs(CLK_SRC_MASK);
 511	mux->mask = CLK_SRC_MASK >> mux->shift;
 512	mux->hw.init = &init;
 513
 514	clk = devm_clk_register(host->dev, &mux->hw);
 515	if (WARN_ON(IS_ERR(clk)))
 516		return PTR_ERR(clk);
 517
 518	/* create the divider */
 519	div = devm_kzalloc(host->dev, sizeof(*div), GFP_KERNEL);
 520	if (!div)
 521		return -ENOMEM;
 522
 523	snprintf(clk_name, sizeof(clk_name), "%s#div", dev_name(host->dev));
 524	init.name = clk_name;
 525	init.ops = &clk_divider_ops;
 526	init.flags = CLK_SET_RATE_PARENT;
 527	clk_parent[0] = __clk_get_name(clk);
 528	init.parent_names = clk_parent;
 529	init.num_parents = 1;
 530
 531	div->reg = host->regs + SD_EMMC_CLOCK;
 532	div->shift = __ffs(CLK_DIV_MASK);
 533	div->width = __builtin_popcountl(CLK_DIV_MASK);
 534	div->hw.init = &init;
 535	div->flags = CLK_DIVIDER_ONE_BASED;
 536
 537	clk = devm_clk_register(host->dev, &div->hw);
 538	if (WARN_ON(IS_ERR(clk)))
 539		return PTR_ERR(clk);
 540
 541	/* create the mmc core clock */
 542	core = devm_kzalloc(host->dev, sizeof(*core), GFP_KERNEL);
 543	if (!core)
 544		return -ENOMEM;
 545
 546	snprintf(clk_name, sizeof(clk_name), "%s#core", dev_name(host->dev));
 547	init.name = clk_name;
 548	init.ops = &meson_mmc_clk_phase_ops;
 549	init.flags = CLK_SET_RATE_PARENT;
 550	clk_parent[0] = __clk_get_name(clk);
 551	init.parent_names = clk_parent;
 552	init.num_parents = 1;
 553
 554	core->reg = host->regs + SD_EMMC_CLOCK;
 555	core->phase_mask = CLK_CORE_PHASE_MASK;
 556	core->hw.init = &init;
 557
 558	host->mmc_clk = devm_clk_register(host->dev, &core->hw);
 559	if (WARN_ON(PTR_ERR_OR_ZERO(host->mmc_clk)))
 560		return PTR_ERR(host->mmc_clk);
 561
 562	/* create the mmc tx clock */
 563	tx = devm_kzalloc(host->dev, sizeof(*tx), GFP_KERNEL);
 564	if (!tx)
 565		return -ENOMEM;
 566
 567	snprintf(clk_name, sizeof(clk_name), "%s#tx", dev_name(host->dev));
 568	init.name = clk_name;
 569	init.ops = &meson_mmc_clk_phase_ops;
 570	init.flags = 0;
 571	clk_parent[0] = __clk_get_name(host->mmc_clk);
 572	init.parent_names = clk_parent;
 573	init.num_parents = 1;
 574
 575	tx->reg = host->regs + SD_EMMC_CLOCK;
 576	tx->phase_mask = CLK_TX_PHASE_MASK;
 577	tx->delay_mask = CLK_TX_DELAY_MASK;
 578	tx->delay_step_ps = CLK_DELAY_STEP_PS;
 579	tx->hw.init = &init;
 580
 581	host->tx_clk = devm_clk_register(host->dev, &tx->hw);
 582	if (WARN_ON(PTR_ERR_OR_ZERO(host->tx_clk)))
 583		return PTR_ERR(host->tx_clk);
 584
 585	/* create the mmc rx clock */
 586	rx = devm_kzalloc(host->dev, sizeof(*rx), GFP_KERNEL);
 587	if (!rx)
 588		return -ENOMEM;
 589
 590	snprintf(clk_name, sizeof(clk_name), "%s#rx", dev_name(host->dev));
 591	init.name = clk_name;
 592	init.ops = &meson_mmc_clk_phase_ops;
 593	init.flags = 0;
 594	clk_parent[0] = __clk_get_name(host->mmc_clk);
 595	init.parent_names = clk_parent;
 596	init.num_parents = 1;
 597
 598	rx->reg = host->regs + SD_EMMC_CLOCK;
 599	rx->phase_mask = CLK_RX_PHASE_MASK;
 600	rx->delay_mask = CLK_RX_DELAY_MASK;
 601	rx->delay_step_ps = CLK_DELAY_STEP_PS;
 602	rx->hw.init = &init;
 603
 604	host->rx_clk = devm_clk_register(host->dev, &rx->hw);
 605	if (WARN_ON(PTR_ERR_OR_ZERO(host->rx_clk)))
 606		return PTR_ERR(host->rx_clk);
 607
 608	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
 609	host->mmc->f_min = clk_round_rate(host->mmc_clk, 400000);
 610	ret = clk_set_rate(host->mmc_clk, host->mmc->f_min);
 611	if (ret)
 612		return ret;
 613
 614	/*
 615	 * Set phases : These values are mostly the datasheet recommended ones
 616	 * except for the Tx phase. Datasheet recommends 180 but some cards
 617	 * fail at initialisation with it. 270 works just fine, it fixes these
 618	 * initialisation issues and enable eMMC DDR52 mode.
 619	 */
 620	clk_set_phase(host->mmc_clk, 180);
 621	clk_set_phase(host->tx_clk, 270);
 622	clk_set_phase(host->rx_clk, 0);
 623
 624	return clk_prepare_enable(host->mmc_clk);
 625}
 626
 627static void meson_mmc_shift_map(unsigned long *map, unsigned long shift)
 628{
 629	DECLARE_BITMAP(left, CLK_PHASE_POINT_NUM);
 630	DECLARE_BITMAP(right, CLK_PHASE_POINT_NUM);
 631
 632	/*
 633	 * shift the bitmap right and reintroduce the dropped bits on the left
 634	 * of the bitmap
 635	 */
 636	bitmap_shift_right(right, map, shift, CLK_PHASE_POINT_NUM);
 637	bitmap_shift_left(left, map, CLK_PHASE_POINT_NUM - shift,
 638			  CLK_PHASE_POINT_NUM);
 639	bitmap_or(map, left, right, CLK_PHASE_POINT_NUM);
 640}
 641
 642static void meson_mmc_find_next_region(unsigned long *map,
 643				       unsigned long *start,
 644				       unsigned long *stop)
 645{
 646	*start = find_next_bit(map, CLK_PHASE_POINT_NUM, *start);
 647	*stop = find_next_zero_bit(map, CLK_PHASE_POINT_NUM, *start);
 648}
 649
 650static int meson_mmc_find_tuning_point(unsigned long *test)
 651{
 652	unsigned long shift, stop, offset = 0, start = 0, size = 0;
 653
 654	/* Get the all good/all bad situation out the way */
 655	if (bitmap_full(test, CLK_PHASE_POINT_NUM))
 656		return 0; /* All points are good so point 0 will do */
 657	else if (bitmap_empty(test, CLK_PHASE_POINT_NUM))
 658		return -EIO; /* No successful tuning point */
 659
 660	/*
 661	 * Now we know there is a least one region find. Make sure it does
 662	 * not wrap by the shifting the bitmap if necessary
 663	 */
 664	shift = find_first_zero_bit(test, CLK_PHASE_POINT_NUM);
 665	if (shift != 0)
 666		meson_mmc_shift_map(test, shift);
 667
 668	while (start < CLK_PHASE_POINT_NUM) {
 669		meson_mmc_find_next_region(test, &start, &stop);
 670
 671		if ((stop - start) > size) {
 672			offset = start;
 673			size = stop - start;
 674		}
 675
 676		start = stop;
 677	}
 678
 679	/* Get the center point of the region */
 680	offset += (size / 2);
 681
 682	/* Shift the result back */
 683	offset = (offset + shift) % CLK_PHASE_POINT_NUM;
 684
 685	return offset;
 686}
 687
 688static int meson_mmc_clk_phase_tuning(struct mmc_host *mmc, u32 opcode,
 689				      struct clk *clk)
 690{
 691	int point, ret;
 692	DECLARE_BITMAP(test, CLK_PHASE_POINT_NUM);
 693
 694	dev_dbg(mmc_dev(mmc), "%s phase/delay tunning...\n",
 695		__clk_get_name(clk));
 696	bitmap_zero(test, CLK_PHASE_POINT_NUM);
 697
 698	/* Explore tuning points */
 699	for (point = 0; point < CLK_PHASE_POINT_NUM; point++) {
 700		clk_set_phase(clk, point * CLK_PHASE_STEP);
 701		ret = mmc_send_tuning(mmc, opcode, NULL);
 702		if (!ret)
 703			set_bit(point, test);
 704	}
 705
 706	/* Find the optimal tuning point and apply it */
 707	point = meson_mmc_find_tuning_point(test);
 708	if (point < 0)
 709		return point; /* tuning failed */
 710
 711	clk_set_phase(clk, point * CLK_PHASE_STEP);
 712	dev_dbg(mmc_dev(mmc), "success with phase: %d\n",
 713		clk_get_phase(clk));
 714	return 0;
 715}
 716
 717static int meson_mmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
 718{
 719	struct meson_host *host = mmc_priv(mmc);
 720
 721	return meson_mmc_clk_phase_tuning(mmc, opcode, host->rx_clk);
 722}
 723
 724static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 725{
 726	struct meson_host *host = mmc_priv(mmc);
 727	u32 bus_width, val;
 728	int err;
 729
 730	/*
 731	 * GPIO regulator, only controls switching between 1v8 and
 732	 * 3v3, doesn't support MMC_POWER_OFF, MMC_POWER_ON.
 733	 */
 734	switch (ios->power_mode) {
 735	case MMC_POWER_OFF:
 736		if (!IS_ERR(mmc->supply.vmmc))
 737			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
 738
 739		if (!IS_ERR(mmc->supply.vqmmc) && host->vqmmc_enabled) {
 740			regulator_disable(mmc->supply.vqmmc);
 741			host->vqmmc_enabled = false;
 742		}
 743
 744		break;
 745
 746	case MMC_POWER_UP:
 747		if (!IS_ERR(mmc->supply.vmmc))
 748			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
 749
 750		/* Reset rx phase */
 751		clk_set_phase(host->rx_clk, 0);
 752
 753		break;
 754
 755	case MMC_POWER_ON:
 756		if (!IS_ERR(mmc->supply.vqmmc) && !host->vqmmc_enabled) {
 757			int ret = regulator_enable(mmc->supply.vqmmc);
 758
 759			if (ret < 0)
 760				dev_err(host->dev,
 761					"failed to enable vqmmc regulator\n");
 762			else
 763				host->vqmmc_enabled = true;
 764		}
 765
 766		break;
 767	}
 768
 769	/* Bus width */
 770	switch (ios->bus_width) {
 771	case MMC_BUS_WIDTH_1:
 772		bus_width = CFG_BUS_WIDTH_1;
 773		break;
 774	case MMC_BUS_WIDTH_4:
 775		bus_width = CFG_BUS_WIDTH_4;
 776		break;
 777	case MMC_BUS_WIDTH_8:
 778		bus_width = CFG_BUS_WIDTH_8;
 779		break;
 780	default:
 781		dev_err(host->dev, "Invalid ios->bus_width: %u.  Setting to 4.\n",
 782			ios->bus_width);
 783		bus_width = CFG_BUS_WIDTH_4;
 784	}
 785
 786	val = readl(host->regs + SD_EMMC_CFG);
 787	val &= ~CFG_BUS_WIDTH_MASK;
 788	val |= FIELD_PREP(CFG_BUS_WIDTH_MASK, bus_width);
 789
 790	val &= ~CFG_DDR;
 791	if (meson_mmc_timing_is_ddr(ios))
 792		val |= CFG_DDR;
 793
 794	val &= ~CFG_CHK_DS;
 795	if (ios->timing == MMC_TIMING_MMC_HS400)
 796		val |= CFG_CHK_DS;
 797
 798	err = meson_mmc_clk_set(host, ios);
 799	if (err)
 800		dev_err(host->dev, "Failed to set clock: %d\n,", err);
 801
 802	writel(val, host->regs + SD_EMMC_CFG);
 803	dev_dbg(host->dev, "SD_EMMC_CFG:  0x%08x\n", val);
 804}
 805
 806static void meson_mmc_request_done(struct mmc_host *mmc,
 807				   struct mmc_request *mrq)
 808{
 809	struct meson_host *host = mmc_priv(mmc);
 810
 811	host->cmd = NULL;
 812	mmc_request_done(host->mmc, mrq);
 813}
 814
 815static void meson_mmc_set_blksz(struct mmc_host *mmc, unsigned int blksz)
 816{
 817	struct meson_host *host = mmc_priv(mmc);
 818	u32 cfg, blksz_old;
 819
 820	cfg = readl(host->regs + SD_EMMC_CFG);
 821	blksz_old = FIELD_GET(CFG_BLK_LEN_MASK, cfg);
 822
 823	if (!is_power_of_2(blksz))
 824		dev_err(host->dev, "blksz %u is not a power of 2\n", blksz);
 825
 826	blksz = ilog2(blksz);
 827
 828	/* check if block-size matches, if not update */
 829	if (blksz == blksz_old)
 830		return;
 831
 832	dev_dbg(host->dev, "%s: update blk_len %d -> %d\n", __func__,
 833		blksz_old, blksz);
 834
 835	cfg &= ~CFG_BLK_LEN_MASK;
 836	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, blksz);
 837	writel(cfg, host->regs + SD_EMMC_CFG);
 838}
 839
 840static void meson_mmc_set_response_bits(struct mmc_command *cmd, u32 *cmd_cfg)
 841{
 842	if (cmd->flags & MMC_RSP_PRESENT) {
 843		if (cmd->flags & MMC_RSP_136)
 844			*cmd_cfg |= CMD_CFG_RESP_128;
 845		*cmd_cfg |= CMD_CFG_RESP_NUM;
 846
 847		if (!(cmd->flags & MMC_RSP_CRC))
 848			*cmd_cfg |= CMD_CFG_RESP_NOCRC;
 849
 850		if (cmd->flags & MMC_RSP_BUSY)
 851			*cmd_cfg |= CMD_CFG_R1B;
 852	} else {
 853		*cmd_cfg |= CMD_CFG_NO_RESP;
 854	}
 855}
 856
 857static void meson_mmc_desc_chain_transfer(struct mmc_host *mmc, u32 cmd_cfg)
 858{
 859	struct meson_host *host = mmc_priv(mmc);
 860	struct sd_emmc_desc *desc = host->descs;
 861	struct mmc_data *data = host->cmd->data;
 862	struct scatterlist *sg;
 863	u32 start;
 864	int i;
 865
 866	if (data->flags & MMC_DATA_WRITE)
 867		cmd_cfg |= CMD_CFG_DATA_WR;
 868
 869	if (data->blocks > 1) {
 870		cmd_cfg |= CMD_CFG_BLOCK_MODE;
 871		meson_mmc_set_blksz(mmc, data->blksz);
 872	}
 873
 874	for_each_sg(data->sg, sg, data->sg_count, i) {
 875		unsigned int len = sg_dma_len(sg);
 876
 877		if (data->blocks > 1)
 878			len /= data->blksz;
 879
 880		desc[i].cmd_cfg = cmd_cfg;
 881		desc[i].cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, len);
 882		if (i > 0)
 883			desc[i].cmd_cfg |= CMD_CFG_NO_CMD;
 884		desc[i].cmd_arg = host->cmd->arg;
 885		desc[i].cmd_resp = 0;
 886		desc[i].cmd_data = sg_dma_address(sg);
 887	}
 888	desc[data->sg_count - 1].cmd_cfg |= CMD_CFG_END_OF_CHAIN;
 889
 890	dma_wmb(); /* ensure descriptor is written before kicked */
 891	start = host->descs_dma_addr | START_DESC_BUSY;
 892	writel(start, host->regs + SD_EMMC_START);
 893}
 894
 895static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
 896{
 897	struct meson_host *host = mmc_priv(mmc);
 898	struct mmc_data *data = cmd->data;
 899	u32 cmd_cfg = 0, cmd_data = 0;
 900	unsigned int xfer_bytes = 0;
 901
 902	/* Setup descriptors */
 903	dma_rmb();
 904
 905	host->cmd = cmd;
 906
 907	cmd_cfg |= FIELD_PREP(CMD_CFG_CMD_INDEX_MASK, cmd->opcode);
 908	cmd_cfg |= CMD_CFG_OWNER;  /* owned by CPU */
 909
 910	meson_mmc_set_response_bits(cmd, &cmd_cfg);
 911
 912	/* data? */
 913	if (data) {
 914		data->bytes_xfered = 0;
 915		cmd_cfg |= CMD_CFG_DATA_IO;
 916		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
 917				      ilog2(meson_mmc_get_timeout_msecs(data)));
 918
 919		if (meson_mmc_desc_chain_mode(data)) {
 920			meson_mmc_desc_chain_transfer(mmc, cmd_cfg);
 921			return;
 922		}
 923
 924		if (data->blocks > 1) {
 925			cmd_cfg |= CMD_CFG_BLOCK_MODE;
 926			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK,
 927					      data->blocks);
 928			meson_mmc_set_blksz(mmc, data->blksz);
 929		} else {
 930			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, data->blksz);
 931		}
 932
 933		xfer_bytes = data->blksz * data->blocks;
 934		if (data->flags & MMC_DATA_WRITE) {
 935			cmd_cfg |= CMD_CFG_DATA_WR;
 936			WARN_ON(xfer_bytes > host->bounce_buf_size);
 937			sg_copy_to_buffer(data->sg, data->sg_len,
 938					  host->bounce_buf, xfer_bytes);
 939			dma_wmb();
 940		}
 941
 942		cmd_data = host->bounce_dma_addr & CMD_DATA_MASK;
 943	} else {
 944		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
 945				      ilog2(SD_EMMC_CMD_TIMEOUT));
 946	}
 947
 948	/* Last descriptor */
 949	cmd_cfg |= CMD_CFG_END_OF_CHAIN;
 950	writel(cmd_cfg, host->regs + SD_EMMC_CMD_CFG);
 951	writel(cmd_data, host->regs + SD_EMMC_CMD_DAT);
 952	writel(0, host->regs + SD_EMMC_CMD_RSP);
 953	wmb(); /* ensure descriptor is written before kicked */
 954	writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG);
 955}
 956
 957static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 958{
 959	struct meson_host *host = mmc_priv(mmc);
 960	bool needs_pre_post_req = mrq->data &&
 961			!(mrq->data->host_cookie & SD_EMMC_PRE_REQ_DONE);
 962
 963	if (needs_pre_post_req) {
 964		meson_mmc_get_transfer_mode(mmc, mrq);
 965		if (!meson_mmc_desc_chain_mode(mrq->data))
 966			needs_pre_post_req = false;
 967	}
 968
 969	if (needs_pre_post_req)
 970		meson_mmc_pre_req(mmc, mrq);
 971
 972	/* Stop execution */
 973	writel(0, host->regs + SD_EMMC_START);
 974
 975	meson_mmc_start_cmd(mmc, mrq->sbc ?: mrq->cmd);
 976
 977	if (needs_pre_post_req)
 978		meson_mmc_post_req(mmc, mrq, 0);
 979}
 980
 981static void meson_mmc_read_resp(struct mmc_host *mmc, struct mmc_command *cmd)
 982{
 983	struct meson_host *host = mmc_priv(mmc);
 984
 985	if (cmd->flags & MMC_RSP_136) {
 986		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP3);
 987		cmd->resp[1] = readl(host->regs + SD_EMMC_CMD_RSP2);
 988		cmd->resp[2] = readl(host->regs + SD_EMMC_CMD_RSP1);
 989		cmd->resp[3] = readl(host->regs + SD_EMMC_CMD_RSP);
 990	} else if (cmd->flags & MMC_RSP_PRESENT) {
 991		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP);
 992	}
 993}
 994
 995static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
 996{
 997	struct meson_host *host = dev_id;
 998	struct mmc_command *cmd;
 999	struct mmc_data *data;
1000	u32 irq_en, status, raw_status;
1001	irqreturn_t ret = IRQ_NONE;
1002
1003	if (WARN_ON(!host) || WARN_ON(!host->cmd))
1004		return IRQ_NONE;
1005
1006	spin_lock(&host->lock);
1007
1008	cmd = host->cmd;
1009	data = cmd->data;
1010	irq_en = readl(host->regs + SD_EMMC_IRQ_EN);
1011	raw_status = readl(host->regs + SD_EMMC_STATUS);
1012	status = raw_status & irq_en;
1013
1014	cmd->error = 0;
1015	if (status & IRQ_CRC_ERR) {
1016		dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status);
1017		cmd->error = -EILSEQ;
1018		ret = IRQ_HANDLED;
1019		goto out;
1020	}
1021
1022	if (status & IRQ_TIMEOUTS) {
1023		dev_dbg(host->dev, "Timeout - status 0x%08x\n", status);
1024		cmd->error = -ETIMEDOUT;
1025		ret = IRQ_HANDLED;
1026		goto out;
1027	}
1028
1029	meson_mmc_read_resp(host->mmc, cmd);
1030
1031	if (status & IRQ_SDIO) {
1032		dev_dbg(host->dev, "IRQ: SDIO TODO.\n");
1033		ret = IRQ_HANDLED;
1034	}
1035
1036	if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
1037		if (data && !cmd->error)
1038			data->bytes_xfered = data->blksz * data->blocks;
1039		if (meson_mmc_bounce_buf_read(data) ||
1040		    meson_mmc_get_next_command(cmd))
1041			ret = IRQ_WAKE_THREAD;
1042		else
1043			ret = IRQ_HANDLED;
1044	}
1045
1046out:
1047	/* ack all enabled interrupts */
1048	writel(irq_en, host->regs + SD_EMMC_STATUS);
1049
1050	if (ret == IRQ_HANDLED)
1051		meson_mmc_request_done(host->mmc, cmd->mrq);
1052	else if (ret == IRQ_NONE)
1053		dev_warn(host->dev,
1054			 "Unexpected IRQ! status=0x%08x, irq_en=0x%08x\n",
1055			 raw_status, irq_en);
1056
1057	spin_unlock(&host->lock);
1058	return ret;
1059}
1060
1061static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id)
1062{
1063	struct meson_host *host = dev_id;
1064	struct mmc_command *next_cmd, *cmd = host->cmd;
1065	struct mmc_data *data;
1066	unsigned int xfer_bytes;
1067
1068	if (WARN_ON(!cmd))
1069		return IRQ_NONE;
1070
1071	data = cmd->data;
1072	if (meson_mmc_bounce_buf_read(data)) {
1073		xfer_bytes = data->blksz * data->blocks;
1074		WARN_ON(xfer_bytes > host->bounce_buf_size);
1075		sg_copy_from_buffer(data->sg, data->sg_len,
1076				    host->bounce_buf, xfer_bytes);
1077	}
1078
1079	next_cmd = meson_mmc_get_next_command(cmd);
1080	if (next_cmd)
1081		meson_mmc_start_cmd(host->mmc, next_cmd);
1082	else
1083		meson_mmc_request_done(host->mmc, cmd->mrq);
1084
1085	return IRQ_HANDLED;
1086}
1087
1088/*
1089 * NOTE: we only need this until the GPIO/pinctrl driver can handle
1090 * interrupts.  For now, the MMC core will use this for polling.
1091 */
1092static int meson_mmc_get_cd(struct mmc_host *mmc)
1093{
1094	int status = mmc_gpio_get_cd(mmc);
1095
1096	if (status == -ENOSYS)
1097		return 1; /* assume present */
1098
1099	return status;
1100}
1101
1102static void meson_mmc_cfg_init(struct meson_host *host)
1103{
1104	u32 cfg = 0;
1105
1106	cfg |= FIELD_PREP(CFG_RESP_TIMEOUT_MASK,
1107			  ilog2(SD_EMMC_CFG_RESP_TIMEOUT));
1108	cfg |= FIELD_PREP(CFG_RC_CC_MASK, ilog2(SD_EMMC_CFG_CMD_GAP));
1109	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, ilog2(SD_EMMC_CFG_BLK_SIZE));
1110
1111	writel(cfg, host->regs + SD_EMMC_CFG);
1112}
1113
1114static int meson_mmc_card_busy(struct mmc_host *mmc)
1115{
1116	struct meson_host *host = mmc_priv(mmc);
1117	u32 regval;
1118
1119	regval = readl(host->regs + SD_EMMC_STATUS);
1120
1121	/* We are only interrested in lines 0 to 3, so mask the other ones */
1122	return !(FIELD_GET(STATUS_DATI, regval) & 0xf);
1123}
1124
1125static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
1126{
1127	/* vqmmc regulator is available */
1128	if (!IS_ERR(mmc->supply.vqmmc)) {
1129		/*
1130		 * The usual amlogic setup uses a GPIO to switch from one
1131		 * regulator to the other. While the voltage ramp up is
1132		 * pretty fast, care must be taken when switching from 3.3v
1133		 * to 1.8v. Please make sure the regulator framework is aware
1134		 * of your own regulator constraints
1135		 */
1136		return mmc_regulator_set_vqmmc(mmc, ios);
1137	}
1138
1139	/* no vqmmc regulator, assume fixed regulator at 3/3.3V */
1140	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1141		return 0;
1142
1143	return -EINVAL;
1144}
1145
1146static const struct mmc_host_ops meson_mmc_ops = {
1147	.request	= meson_mmc_request,
1148	.set_ios	= meson_mmc_set_ios,
1149	.get_cd         = meson_mmc_get_cd,
1150	.pre_req	= meson_mmc_pre_req,
1151	.post_req	= meson_mmc_post_req,
1152	.execute_tuning = meson_mmc_execute_tuning,
1153	.card_busy	= meson_mmc_card_busy,
1154	.start_signal_voltage_switch = meson_mmc_voltage_switch,
1155};
1156
1157static int meson_mmc_probe(struct platform_device *pdev)
1158{
1159	struct resource *res;
1160	struct meson_host *host;
1161	struct mmc_host *mmc;
1162	int ret, irq;
1163
1164	mmc = mmc_alloc_host(sizeof(struct meson_host), &pdev->dev);
1165	if (!mmc)
1166		return -ENOMEM;
1167	host = mmc_priv(mmc);
1168	host->mmc = mmc;
1169	host->dev = &pdev->dev;
1170	dev_set_drvdata(&pdev->dev, host);
1171
1172	spin_lock_init(&host->lock);
1173
1174	/* Get regulators and the supported OCR mask */
1175	host->vqmmc_enabled = false;
1176	ret = mmc_regulator_get_supply(mmc);
1177	if (ret)
1178		goto free_host;
1179
1180	ret = mmc_of_parse(mmc);
1181	if (ret) {
1182		if (ret != -EPROBE_DEFER)
1183			dev_warn(&pdev->dev, "error parsing DT: %d\n", ret);
1184		goto free_host;
1185	}
1186
1187	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1188	host->regs = devm_ioremap_resource(&pdev->dev, res);
1189	if (IS_ERR(host->regs)) {
1190		ret = PTR_ERR(host->regs);
1191		goto free_host;
1192	}
1193
1194	irq = platform_get_irq(pdev, 0);
1195	if (irq <= 0) {
1196		dev_err(&pdev->dev, "failed to get interrupt resource.\n");
1197		ret = -EINVAL;
1198		goto free_host;
1199	}
1200
1201	host->pinctrl = devm_pinctrl_get(&pdev->dev);
1202	if (IS_ERR(host->pinctrl)) {
1203		ret = PTR_ERR(host->pinctrl);
1204		goto free_host;
1205	}
1206
1207	host->pins_default = pinctrl_lookup_state(host->pinctrl,
1208						  PINCTRL_STATE_DEFAULT);
1209	if (IS_ERR(host->pins_default)) {
1210		ret = PTR_ERR(host->pins_default);
1211		goto free_host;
1212	}
1213
1214	host->pins_clk_gate = pinctrl_lookup_state(host->pinctrl,
1215						   "clk-gate");
1216	if (IS_ERR(host->pins_clk_gate)) {
1217		dev_warn(&pdev->dev,
1218			 "can't get clk-gate pinctrl, using clk_stop bit\n");
1219		host->pins_clk_gate = NULL;
1220	}
1221
1222	host->core_clk = devm_clk_get(&pdev->dev, "core");
1223	if (IS_ERR(host->core_clk)) {
1224		ret = PTR_ERR(host->core_clk);
1225		goto free_host;
1226	}
1227
1228	ret = clk_prepare_enable(host->core_clk);
1229	if (ret)
1230		goto free_host;
1231
1232	ret = meson_mmc_clk_init(host);
1233	if (ret)
1234		goto err_core_clk;
1235
1236	/* set config to sane default */
1237	meson_mmc_cfg_init(host);
1238
1239	/* Stop execution */
1240	writel(0, host->regs + SD_EMMC_START);
1241
1242	/* clear, ack and enable interrupts */
1243	writel(0, host->regs + SD_EMMC_IRQ_EN);
1244	writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN,
1245	       host->regs + SD_EMMC_STATUS);
1246	writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN,
1247	       host->regs + SD_EMMC_IRQ_EN);
1248
1249	ret = devm_request_threaded_irq(&pdev->dev, irq, meson_mmc_irq,
1250					meson_mmc_irq_thread, IRQF_SHARED,
1251					NULL, host);
1252	if (ret)
1253		goto err_init_clk;
1254
1255	mmc->caps |= MMC_CAP_CMD23;
1256	mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
1257	mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
1258	mmc->max_segs = SD_EMMC_DESC_BUF_LEN / sizeof(struct sd_emmc_desc);
1259	mmc->max_seg_size = mmc->max_req_size;
1260
1261	/* data bounce buffer */
1262	host->bounce_buf_size = mmc->max_req_size;
1263	host->bounce_buf =
1264		dma_alloc_coherent(host->dev, host->bounce_buf_size,
1265				   &host->bounce_dma_addr, GFP_KERNEL);
1266	if (host->bounce_buf == NULL) {
1267		dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
1268		ret = -ENOMEM;
1269		goto err_init_clk;
1270	}
1271
1272	host->descs = dma_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
1273		      &host->descs_dma_addr, GFP_KERNEL);
1274	if (!host->descs) {
1275		dev_err(host->dev, "Allocating descriptor DMA buffer failed\n");
1276		ret = -ENOMEM;
1277		goto err_bounce_buf;
1278	}
1279
1280	mmc->ops = &meson_mmc_ops;
1281	mmc_add_host(mmc);
1282
1283	return 0;
1284
1285err_bounce_buf:
1286	dma_free_coherent(host->dev, host->bounce_buf_size,
1287			  host->bounce_buf, host->bounce_dma_addr);
1288err_init_clk:
1289	clk_disable_unprepare(host->mmc_clk);
1290err_core_clk:
1291	clk_disable_unprepare(host->core_clk);
1292free_host:
1293	mmc_free_host(mmc);
1294	return ret;
1295}
1296
1297static int meson_mmc_remove(struct platform_device *pdev)
1298{
1299	struct meson_host *host = dev_get_drvdata(&pdev->dev);
1300
1301	mmc_remove_host(host->mmc);
1302
1303	/* disable interrupts */
1304	writel(0, host->regs + SD_EMMC_IRQ_EN);
1305
1306	dma_free_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
1307			  host->descs, host->descs_dma_addr);
1308	dma_free_coherent(host->dev, host->bounce_buf_size,
1309			  host->bounce_buf, host->bounce_dma_addr);
1310
1311	clk_disable_unprepare(host->mmc_clk);
1312	clk_disable_unprepare(host->core_clk);
1313
1314	mmc_free_host(host->mmc);
1315	return 0;
1316}
1317
1318static const struct of_device_id meson_mmc_of_match[] = {
1319	{ .compatible = "amlogic,meson-gx-mmc", },
1320	{ .compatible = "amlogic,meson-gxbb-mmc", },
1321	{ .compatible = "amlogic,meson-gxl-mmc", },
1322	{ .compatible = "amlogic,meson-gxm-mmc", },
1323	{}
1324};
1325MODULE_DEVICE_TABLE(of, meson_mmc_of_match);
1326
1327static struct platform_driver meson_mmc_driver = {
1328	.probe		= meson_mmc_probe,
1329	.remove		= meson_mmc_remove,
1330	.driver		= {
1331		.name = DRIVER_NAME,
1332		.of_match_table = of_match_ptr(meson_mmc_of_match),
1333	},
1334};
1335
1336module_platform_driver(meson_mmc_driver);
1337
1338MODULE_DESCRIPTION("Amlogic S905*/GX* SD/eMMC driver");
1339MODULE_AUTHOR("Kevin Hilman <khilman@baylibre.com>");
1340MODULE_LICENSE("GPL v2");