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v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2// Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
   3
   4#include <linux/clk.h>
   5#include <linux/dmaengine.h>
   6#include <linux/dma-mapping.h>
   7#include <linux/dma/qcom-gpi-dma.h>
   8#include <linux/interrupt.h>
   9#include <linux/io.h>
  10#include <linux/log2.h>
  11#include <linux/module.h>
  12#include <linux/platform_device.h>
  13#include <linux/pm_opp.h>
  14#include <linux/pm_runtime.h>
  15#include <linux/qcom-geni-se.h>
 
  16#include <linux/spi/spi.h>
  17#include <linux/spinlock.h>
  18
  19/* SPI SE specific registers and respective register fields */
  20#define SE_SPI_CPHA		0x224
  21#define CPHA			BIT(0)
  22
  23#define SE_SPI_LOOPBACK		0x22c
  24#define LOOPBACK_ENABLE		0x1
  25#define NORMAL_MODE		0x0
  26#define LOOPBACK_MSK		GENMASK(1, 0)
  27
  28#define SE_SPI_CPOL		0x230
  29#define CPOL			BIT(2)
  30
  31#define SE_SPI_DEMUX_OUTPUT_INV	0x24c
  32#define CS_DEMUX_OUTPUT_INV_MSK	GENMASK(3, 0)
  33
  34#define SE_SPI_DEMUX_SEL	0x250
  35#define CS_DEMUX_OUTPUT_SEL	GENMASK(3, 0)
  36
  37#define SE_SPI_TRANS_CFG	0x25c
  38#define CS_TOGGLE		BIT(0)
  39
  40#define SE_SPI_WORD_LEN		0x268
  41#define WORD_LEN_MSK		GENMASK(9, 0)
  42#define MIN_WORD_LEN		4
  43
  44#define SE_SPI_TX_TRANS_LEN	0x26c
  45#define SE_SPI_RX_TRANS_LEN	0x270
  46#define TRANS_LEN_MSK		GENMASK(23, 0)
  47
  48#define SE_SPI_PRE_POST_CMD_DLY	0x274
  49
  50#define SE_SPI_DELAY_COUNTERS	0x278
  51#define SPI_INTER_WORDS_DELAY_MSK	GENMASK(9, 0)
  52#define SPI_CS_CLK_DELAY_MSK		GENMASK(19, 10)
  53#define SPI_CS_CLK_DELAY_SHFT		10
  54
 
 
 
  55/* M_CMD OP codes for SPI */
  56#define SPI_TX_ONLY		1
  57#define SPI_RX_ONLY		2
  58#define SPI_TX_RX		7
  59#define SPI_CS_ASSERT		8
  60#define SPI_CS_DEASSERT		9
  61#define SPI_SCK_ONLY		10
  62/* M_CMD params for SPI */
  63#define SPI_PRE_CMD_DELAY	BIT(0)
  64#define TIMESTAMP_BEFORE	BIT(1)
  65#define FRAGMENTATION		BIT(2)
  66#define TIMESTAMP_AFTER		BIT(3)
  67#define POST_CMD_DELAY		BIT(4)
  68
  69#define GSI_LOOPBACK_EN		BIT(0)
  70#define GSI_CS_TOGGLE		BIT(3)
  71#define GSI_CPHA		BIT(4)
  72#define GSI_CPOL		BIT(5)
  73
  74struct spi_geni_master {
  75	struct geni_se se;
  76	struct device *dev;
  77	u32 tx_fifo_depth;
  78	u32 fifo_width_bits;
  79	u32 tx_wm;
  80	u32 last_mode;
  81	unsigned long cur_speed_hz;
  82	unsigned long cur_sclk_hz;
  83	unsigned int cur_bits_per_word;
  84	unsigned int tx_rem_bytes;
  85	unsigned int rx_rem_bytes;
  86	const struct spi_transfer *cur_xfer;
  87	struct completion cs_done;
  88	struct completion cancel_done;
  89	struct completion abort_done;
 
 
  90	unsigned int oversampling;
  91	spinlock_t lock;
  92	int irq;
  93	bool cs_flag;
  94	bool abort_failed;
  95	struct dma_chan *tx;
  96	struct dma_chan *rx;
  97	int cur_xfer_mode;
  98};
  99
 
 
 
 
 
 
 
 
 
 
 100static int get_spi_clk_cfg(unsigned int speed_hz,
 101			struct spi_geni_master *mas,
 102			unsigned int *clk_idx,
 103			unsigned int *clk_div)
 104{
 105	unsigned long sclk_freq;
 106	unsigned int actual_hz;
 107	int ret;
 108
 109	ret = geni_se_clk_freq_match(&mas->se,
 110				speed_hz * mas->oversampling,
 111				clk_idx, &sclk_freq, false);
 112	if (ret) {
 113		dev_err(mas->dev, "Failed(%d) to find src clk for %dHz\n",
 114							ret, speed_hz);
 115		return ret;
 116	}
 117
 118	*clk_div = DIV_ROUND_UP(sclk_freq, mas->oversampling * speed_hz);
 119	actual_hz = sclk_freq / (mas->oversampling * *clk_div);
 120
 121	dev_dbg(mas->dev, "req %u=>%u sclk %lu, idx %d, div %d\n", speed_hz,
 122				actual_hz, sclk_freq, *clk_idx, *clk_div);
 123	ret = dev_pm_opp_set_rate(mas->dev, sclk_freq);
 124	if (ret)
 125		dev_err(mas->dev, "dev_pm_opp_set_rate failed %d\n", ret);
 126	else
 127		mas->cur_sclk_hz = sclk_freq;
 128
 129	return ret;
 130}
 131
 132static void handle_fifo_timeout(struct spi_master *spi,
 133				struct spi_message *msg)
 134{
 135	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 136	unsigned long time_left;
 137	struct geni_se *se = &mas->se;
 
 138
 139	spin_lock_irq(&mas->lock);
 140	reinit_completion(&mas->cancel_done);
 141	writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 
 
 142	mas->cur_xfer = NULL;
 
 
 
 
 
 
 
 
 
 
 
 143	geni_se_cancel_m_cmd(se);
 144	spin_unlock_irq(&mas->lock);
 145
 146	time_left = wait_for_completion_timeout(&mas->cancel_done, HZ);
 147	if (time_left)
 148		return;
 149
 150	spin_lock_irq(&mas->lock);
 151	reinit_completion(&mas->abort_done);
 152	geni_se_abort_m_cmd(se);
 153	spin_unlock_irq(&mas->lock);
 154
 155	time_left = wait_for_completion_timeout(&mas->abort_done, HZ);
 156	if (!time_left) {
 157		dev_err(mas->dev, "Failed to cancel/abort m_cmd\n");
 158
 159		/*
 160		 * No need for a lock since SPI core has a lock and we never
 161		 * access this from an interrupt.
 162		 */
 163		mas->abort_failed = true;
 164	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 165}
 166
 167static void handle_gpi_timeout(struct spi_master *spi, struct spi_message *msg)
 168{
 169	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 170
 171	dmaengine_terminate_sync(mas->tx);
 172	dmaengine_terminate_sync(mas->rx);
 173}
 174
 175static void spi_geni_handle_err(struct spi_master *spi, struct spi_message *msg)
 176{
 177	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 178
 179	switch (mas->cur_xfer_mode) {
 180	case GENI_SE_FIFO:
 181		handle_fifo_timeout(spi, msg);
 
 182		break;
 183	case GENI_GPI_DMA:
 184		handle_gpi_timeout(spi, msg);
 185		break;
 186	default:
 187		dev_err(mas->dev, "Abort on Mode:%d not supported", mas->cur_xfer_mode);
 188	}
 189}
 190
 191static bool spi_geni_is_abort_still_pending(struct spi_geni_master *mas)
 192{
 193	struct geni_se *se = &mas->se;
 194	u32 m_irq, m_irq_en;
 195
 196	if (!mas->abort_failed)
 197		return false;
 198
 199	/*
 200	 * The only known case where a transfer times out and then a cancel
 201	 * times out then an abort times out is if something is blocking our
 202	 * interrupt handler from running.  Avoid starting any new transfers
 203	 * until that sorts itself out.
 204	 */
 205	spin_lock_irq(&mas->lock);
 206	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
 207	m_irq_en = readl(se->base + SE_GENI_M_IRQ_EN);
 208	spin_unlock_irq(&mas->lock);
 209
 210	if (m_irq & m_irq_en) {
 211		dev_err(mas->dev, "Interrupts pending after abort: %#010x\n",
 212			m_irq & m_irq_en);
 213		return true;
 214	}
 215
 216	/*
 217	 * If we're here the problem resolved itself so no need to check more
 218	 * on future transfers.
 219	 */
 220	mas->abort_failed = false;
 221
 222	return false;
 223}
 224
 225static void spi_geni_set_cs(struct spi_device *slv, bool set_flag)
 226{
 227	struct spi_geni_master *mas = spi_master_get_devdata(slv->master);
 228	struct spi_master *spi = dev_get_drvdata(mas->dev);
 229	struct geni_se *se = &mas->se;
 230	unsigned long time_left;
 231
 232	if (!(slv->mode & SPI_CS_HIGH))
 233		set_flag = !set_flag;
 234
 235	if (set_flag == mas->cs_flag)
 236		return;
 237
 238	pm_runtime_get_sync(mas->dev);
 239
 240	if (spi_geni_is_abort_still_pending(mas)) {
 241		dev_err(mas->dev, "Can't set chip select\n");
 242		goto exit;
 243	}
 244
 245	spin_lock_irq(&mas->lock);
 246	if (mas->cur_xfer) {
 247		dev_err(mas->dev, "Can't set CS when prev xfer running\n");
 248		spin_unlock_irq(&mas->lock);
 249		goto exit;
 250	}
 251
 252	mas->cs_flag = set_flag;
 
 
 
 
 253	reinit_completion(&mas->cs_done);
 254	if (set_flag)
 255		geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0);
 256	else
 257		geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0);
 258	spin_unlock_irq(&mas->lock);
 259
 260	time_left = wait_for_completion_timeout(&mas->cs_done, HZ);
 261	if (!time_left) {
 262		dev_warn(mas->dev, "Timeout setting chip select\n");
 263		handle_fifo_timeout(spi, NULL);
 264	}
 265
 266exit:
 267	pm_runtime_put(mas->dev);
 268}
 269
 270static void spi_setup_word_len(struct spi_geni_master *mas, u16 mode,
 271					unsigned int bits_per_word)
 272{
 273	unsigned int pack_words;
 274	bool msb_first = (mode & SPI_LSB_FIRST) ? false : true;
 275	struct geni_se *se = &mas->se;
 276	u32 word_len;
 277
 278	/*
 279	 * If bits_per_word isn't a byte aligned value, set the packing to be
 280	 * 1 SPI word per FIFO word.
 281	 */
 282	if (!(mas->fifo_width_bits % bits_per_word))
 283		pack_words = mas->fifo_width_bits / bits_per_word;
 284	else
 285		pack_words = 1;
 286	geni_se_config_packing(&mas->se, bits_per_word, pack_words, msb_first,
 287								true, true);
 288	word_len = (bits_per_word - MIN_WORD_LEN) & WORD_LEN_MSK;
 289	writel(word_len, se->base + SE_SPI_WORD_LEN);
 290}
 291
 292static int geni_spi_set_clock_and_bw(struct spi_geni_master *mas,
 293					unsigned long clk_hz)
 294{
 295	u32 clk_sel, m_clk_cfg, idx, div;
 296	struct geni_se *se = &mas->se;
 297	int ret;
 298
 299	if (clk_hz == mas->cur_speed_hz)
 300		return 0;
 301
 302	ret = get_spi_clk_cfg(clk_hz, mas, &idx, &div);
 303	if (ret) {
 304		dev_err(mas->dev, "Err setting clk to %lu: %d\n", clk_hz, ret);
 305		return ret;
 306	}
 307
 308	/*
 309	 * SPI core clock gets configured with the requested frequency
 310	 * or the frequency closer to the requested frequency.
 311	 * For that reason requested frequency is stored in the
 312	 * cur_speed_hz and referred in the consecutive transfer instead
 313	 * of calling clk_get_rate() API.
 314	 */
 315	mas->cur_speed_hz = clk_hz;
 316
 317	clk_sel = idx & CLK_SEL_MSK;
 318	m_clk_cfg = (div << CLK_DIV_SHFT) | SER_CLK_EN;
 319	writel(clk_sel, se->base + SE_GENI_CLK_SEL);
 320	writel(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG);
 321
 322	/* Set BW quota for CPU as driver supports FIFO mode only. */
 323	se->icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(mas->cur_speed_hz);
 324	ret = geni_icc_set_bw(se);
 325	if (ret)
 326		return ret;
 327
 328	return 0;
 329}
 330
 331static int setup_fifo_params(struct spi_device *spi_slv,
 332					struct spi_master *spi)
 333{
 334	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 335	struct geni_se *se = &mas->se;
 336	u32 loopback_cfg = 0, cpol = 0, cpha = 0, demux_output_inv = 0;
 337	u32 demux_sel;
 338
 339	if (mas->last_mode != spi_slv->mode) {
 340		if (spi_slv->mode & SPI_LOOP)
 341			loopback_cfg = LOOPBACK_ENABLE;
 342
 343		if (spi_slv->mode & SPI_CPOL)
 344			cpol = CPOL;
 345
 346		if (spi_slv->mode & SPI_CPHA)
 347			cpha = CPHA;
 348
 349		if (spi_slv->mode & SPI_CS_HIGH)
 350			demux_output_inv = BIT(spi_slv->chip_select);
 351
 352		demux_sel = spi_slv->chip_select;
 353		mas->cur_bits_per_word = spi_slv->bits_per_word;
 354
 355		spi_setup_word_len(mas, spi_slv->mode, spi_slv->bits_per_word);
 356		writel(loopback_cfg, se->base + SE_SPI_LOOPBACK);
 357		writel(demux_sel, se->base + SE_SPI_DEMUX_SEL);
 358		writel(cpha, se->base + SE_SPI_CPHA);
 359		writel(cpol, se->base + SE_SPI_CPOL);
 360		writel(demux_output_inv, se->base + SE_SPI_DEMUX_OUTPUT_INV);
 361
 362		mas->last_mode = spi_slv->mode;
 363	}
 364
 365	return geni_spi_set_clock_and_bw(mas, spi_slv->max_speed_hz);
 366}
 367
 368static void
 369spi_gsi_callback_result(void *cb, const struct dmaengine_result *result)
 370{
 371	struct spi_master *spi = cb;
 372
 373	spi->cur_msg->status = -EIO;
 374	if (result->result != DMA_TRANS_NOERROR) {
 375		dev_err(&spi->dev, "DMA txn failed: %d\n", result->result);
 376		spi_finalize_current_transfer(spi);
 377		return;
 378	}
 379
 380	if (!result->residue) {
 381		spi->cur_msg->status = 0;
 382		dev_dbg(&spi->dev, "DMA txn completed\n");
 383	} else {
 384		dev_err(&spi->dev, "DMA xfer has pending: %d\n", result->residue);
 385	}
 386
 387	spi_finalize_current_transfer(spi);
 388}
 389
 390static int setup_gsi_xfer(struct spi_transfer *xfer, struct spi_geni_master *mas,
 391			  struct spi_device *spi_slv, struct spi_master *spi)
 392{
 393	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
 394	struct dma_slave_config config = {};
 395	struct gpi_spi_config peripheral = {};
 396	struct dma_async_tx_descriptor *tx_desc, *rx_desc;
 397	int ret;
 398
 399	config.peripheral_config = &peripheral;
 400	config.peripheral_size = sizeof(peripheral);
 401	peripheral.set_config = true;
 402
 403	if (xfer->bits_per_word != mas->cur_bits_per_word ||
 404	    xfer->speed_hz != mas->cur_speed_hz) {
 405		mas->cur_bits_per_word = xfer->bits_per_word;
 406		mas->cur_speed_hz = xfer->speed_hz;
 407	}
 408
 409	if (xfer->tx_buf && xfer->rx_buf) {
 410		peripheral.cmd = SPI_DUPLEX;
 411	} else if (xfer->tx_buf) {
 412		peripheral.cmd = SPI_TX;
 413		peripheral.rx_len = 0;
 414	} else if (xfer->rx_buf) {
 415		peripheral.cmd = SPI_RX;
 416		if (!(mas->cur_bits_per_word % MIN_WORD_LEN)) {
 417			peripheral.rx_len = ((xfer->len << 3) / mas->cur_bits_per_word);
 418		} else {
 419			int bytes_per_word = (mas->cur_bits_per_word / BITS_PER_BYTE) + 1;
 420
 421			peripheral.rx_len = (xfer->len / bytes_per_word);
 422		}
 423	}
 424
 425	peripheral.loopback_en = !!(spi_slv->mode & SPI_LOOP);
 426	peripheral.clock_pol_high = !!(spi_slv->mode & SPI_CPOL);
 427	peripheral.data_pol_high = !!(spi_slv->mode & SPI_CPHA);
 428	peripheral.cs = spi_slv->chip_select;
 429	peripheral.pack_en = true;
 430	peripheral.word_len = xfer->bits_per_word - MIN_WORD_LEN;
 431
 432	ret = get_spi_clk_cfg(mas->cur_speed_hz, mas,
 433			      &peripheral.clk_src, &peripheral.clk_div);
 434	if (ret) {
 435		dev_err(mas->dev, "Err in get_spi_clk_cfg() :%d\n", ret);
 436		return ret;
 437	}
 438
 439	if (!xfer->cs_change) {
 440		if (!list_is_last(&xfer->transfer_list, &spi->cur_msg->transfers))
 441			peripheral.fragmentation = FRAGMENTATION;
 442	}
 443
 444	if (peripheral.cmd & SPI_RX) {
 445		dmaengine_slave_config(mas->rx, &config);
 446		rx_desc = dmaengine_prep_slave_sg(mas->rx, xfer->rx_sg.sgl, xfer->rx_sg.nents,
 447						  DMA_DEV_TO_MEM, flags);
 448		if (!rx_desc) {
 449			dev_err(mas->dev, "Err setting up rx desc\n");
 450			return -EIO;
 451		}
 452	}
 453
 454	/*
 455	 * Prepare the TX always, even for RX or tx_buf being null, we would
 456	 * need TX to be prepared per GSI spec
 457	 */
 458	dmaengine_slave_config(mas->tx, &config);
 459	tx_desc = dmaengine_prep_slave_sg(mas->tx, xfer->tx_sg.sgl, xfer->tx_sg.nents,
 460					  DMA_MEM_TO_DEV, flags);
 461	if (!tx_desc) {
 462		dev_err(mas->dev, "Err setting up tx desc\n");
 463		return -EIO;
 464	}
 465
 466	tx_desc->callback_result = spi_gsi_callback_result;
 467	tx_desc->callback_param = spi;
 468
 469	if (peripheral.cmd & SPI_RX)
 470		dmaengine_submit(rx_desc);
 471	dmaengine_submit(tx_desc);
 472
 473	if (peripheral.cmd & SPI_RX)
 474		dma_async_issue_pending(mas->rx);
 475
 476	dma_async_issue_pending(mas->tx);
 477	return 1;
 478}
 479
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 480static bool geni_can_dma(struct spi_controller *ctlr,
 481			 struct spi_device *slv, struct spi_transfer *xfer)
 482{
 483	struct spi_geni_master *mas = spi_master_get_devdata(slv->master);
 
 
 
 
 
 
 
 
 
 
 
 484
 485	/* check if dma is supported */
 486	return mas->cur_xfer_mode != GENI_SE_FIFO;
 
 
 487}
 488
 489static int spi_geni_prepare_message(struct spi_master *spi,
 490					struct spi_message *spi_msg)
 491{
 492	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 493	int ret;
 494
 495	switch (mas->cur_xfer_mode) {
 496	case GENI_SE_FIFO:
 
 497		if (spi_geni_is_abort_still_pending(mas))
 498			return -EBUSY;
 499		ret = setup_fifo_params(spi_msg->spi, spi);
 500		if (ret)
 501			dev_err(mas->dev, "Couldn't select mode %d\n", ret);
 502		return ret;
 503
 504	case GENI_GPI_DMA:
 505		/* nothing to do for GPI DMA */
 506		return 0;
 507	}
 508
 509	dev_err(mas->dev, "Mode not supported %d", mas->cur_xfer_mode);
 510	return -EINVAL;
 511}
 512
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 513static int spi_geni_grab_gpi_chan(struct spi_geni_master *mas)
 514{
 515	int ret;
 516
 517	mas->tx = dma_request_chan(mas->dev, "tx");
 518	if (IS_ERR(mas->tx)) {
 519		ret = dev_err_probe(mas->dev, PTR_ERR(mas->tx),
 520				    "Failed to get tx DMA ch\n");
 521		goto err_tx;
 522	}
 523
 524	mas->rx = dma_request_chan(mas->dev, "rx");
 525	if (IS_ERR(mas->rx)) {
 526		ret = dev_err_probe(mas->dev, PTR_ERR(mas->rx),
 527				    "Failed to get rx DMA ch\n");
 528		goto err_rx;
 529	}
 530
 
 
 
 
 
 
 531	return 0;
 532
 533err_rx:
 534	mas->rx = NULL;
 535	dma_release_channel(mas->tx);
 536err_tx:
 537	mas->tx = NULL;
 538	return ret;
 539}
 540
 541static void spi_geni_release_dma_chan(struct spi_geni_master *mas)
 542{
 543	if (mas->rx) {
 544		dma_release_channel(mas->rx);
 545		mas->rx = NULL;
 546	}
 547
 548	if (mas->tx) {
 549		dma_release_channel(mas->tx);
 550		mas->tx = NULL;
 551	}
 552}
 553
 554static int spi_geni_init(struct spi_geni_master *mas)
 555{
 
 556	struct geni_se *se = &mas->se;
 557	unsigned int proto, major, minor, ver;
 558	u32 spi_tx_cfg, fifo_disable;
 559	int ret = -ENXIO;
 560
 561	pm_runtime_get_sync(mas->dev);
 562
 563	proto = geni_se_read_proto(se);
 564	if (proto != GENI_SE_SPI) {
 
 
 
 
 
 
 
 565		dev_err(mas->dev, "Invalid proto %d\n", proto);
 566		goto out_pm;
 567	}
 568	mas->tx_fifo_depth = geni_se_get_tx_fifo_depth(se);
 569
 570	/* Width of Tx and Rx FIFO is same */
 571	mas->fifo_width_bits = geni_se_get_tx_fifo_width(se);
 572
 573	/*
 574	 * Hardware programming guide suggests to configure
 575	 * RX FIFO RFR level to fifo_depth-2.
 576	 */
 577	geni_se_init(se, mas->tx_fifo_depth - 3, mas->tx_fifo_depth - 2);
 578	/* Transmit an entire FIFO worth of data per IRQ */
 579	mas->tx_wm = 1;
 580	ver = geni_se_get_qup_hw_version(se);
 581	major = GENI_SE_VERSION_MAJOR(ver);
 582	minor = GENI_SE_VERSION_MINOR(ver);
 583
 584	if (major == 1 && minor == 0)
 585		mas->oversampling = 2;
 586	else
 587		mas->oversampling = 1;
 588
 589	fifo_disable = readl(se->base + GENI_IF_DISABLE_RO) & FIFO_IF_DISABLE;
 590	switch (fifo_disable) {
 591	case 1:
 592		ret = spi_geni_grab_gpi_chan(mas);
 593		if (!ret) { /* success case */
 594			mas->cur_xfer_mode = GENI_GPI_DMA;
 595			geni_se_select_mode(se, GENI_GPI_DMA);
 596			dev_dbg(mas->dev, "Using GPI DMA mode for SPI\n");
 597			break;
 
 
 598		}
 599		/*
 600		 * in case of failure to get dma channel, we can still do the
 601		 * FIFO mode, so fallthrough
 602		 */
 603		dev_warn(mas->dev, "FIFO mode disabled, but couldn't get DMA, fall back to FIFO mode\n");
 604		fallthrough;
 605
 606	case 0:
 607		mas->cur_xfer_mode = GENI_SE_FIFO;
 608		geni_se_select_mode(se, GENI_SE_FIFO);
 609		ret = 0;
 610		break;
 611	}
 612
 613	/* We always control CS manually */
 614	spi_tx_cfg = readl(se->base + SE_SPI_TRANS_CFG);
 615	spi_tx_cfg &= ~CS_TOGGLE;
 616	writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG);
 
 
 617
 618out_pm:
 619	pm_runtime_put(mas->dev);
 620	return ret;
 621}
 622
 623static unsigned int geni_byte_per_fifo_word(struct spi_geni_master *mas)
 624{
 625	/*
 626	 * Calculate how many bytes we'll put in each FIFO word.  If the
 627	 * transfer words don't pack cleanly into a FIFO word we'll just put
 628	 * one transfer word in each FIFO word.  If they do pack we'll pack 'em.
 629	 */
 630	if (mas->fifo_width_bits % mas->cur_bits_per_word)
 631		return roundup_pow_of_two(DIV_ROUND_UP(mas->cur_bits_per_word,
 632						       BITS_PER_BYTE));
 633
 634	return mas->fifo_width_bits / BITS_PER_BYTE;
 635}
 636
 637static bool geni_spi_handle_tx(struct spi_geni_master *mas)
 638{
 639	struct geni_se *se = &mas->se;
 640	unsigned int max_bytes;
 641	const u8 *tx_buf;
 642	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
 643	unsigned int i = 0;
 644
 645	/* Stop the watermark IRQ if nothing to send */
 646	if (!mas->cur_xfer) {
 647		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 648		return false;
 649	}
 650
 651	max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * bytes_per_fifo_word;
 652	if (mas->tx_rem_bytes < max_bytes)
 653		max_bytes = mas->tx_rem_bytes;
 654
 655	tx_buf = mas->cur_xfer->tx_buf + mas->cur_xfer->len - mas->tx_rem_bytes;
 656	while (i < max_bytes) {
 657		unsigned int j;
 658		unsigned int bytes_to_write;
 659		u32 fifo_word = 0;
 660		u8 *fifo_byte = (u8 *)&fifo_word;
 661
 662		bytes_to_write = min(bytes_per_fifo_word, max_bytes - i);
 663		for (j = 0; j < bytes_to_write; j++)
 664			fifo_byte[j] = tx_buf[i++];
 665		iowrite32_rep(se->base + SE_GENI_TX_FIFOn, &fifo_word, 1);
 666	}
 667	mas->tx_rem_bytes -= max_bytes;
 668	if (!mas->tx_rem_bytes) {
 669		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 670		return false;
 671	}
 672	return true;
 673}
 674
 675static void geni_spi_handle_rx(struct spi_geni_master *mas)
 676{
 677	struct geni_se *se = &mas->se;
 678	u32 rx_fifo_status;
 679	unsigned int rx_bytes;
 680	unsigned int rx_last_byte_valid;
 681	u8 *rx_buf;
 682	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
 683	unsigned int i = 0;
 684
 685	rx_fifo_status = readl(se->base + SE_GENI_RX_FIFO_STATUS);
 686	rx_bytes = (rx_fifo_status & RX_FIFO_WC_MSK) * bytes_per_fifo_word;
 687	if (rx_fifo_status & RX_LAST) {
 688		rx_last_byte_valid = rx_fifo_status & RX_LAST_BYTE_VALID_MSK;
 689		rx_last_byte_valid >>= RX_LAST_BYTE_VALID_SHFT;
 690		if (rx_last_byte_valid && rx_last_byte_valid < 4)
 691			rx_bytes -= bytes_per_fifo_word - rx_last_byte_valid;
 692	}
 693
 694	/* Clear out the FIFO and bail if nowhere to put it */
 695	if (!mas->cur_xfer) {
 696		for (i = 0; i < DIV_ROUND_UP(rx_bytes, bytes_per_fifo_word); i++)
 697			readl(se->base + SE_GENI_RX_FIFOn);
 698		return;
 699	}
 700
 701	if (mas->rx_rem_bytes < rx_bytes)
 702		rx_bytes = mas->rx_rem_bytes;
 703
 704	rx_buf = mas->cur_xfer->rx_buf + mas->cur_xfer->len - mas->rx_rem_bytes;
 705	while (i < rx_bytes) {
 706		u32 fifo_word = 0;
 707		u8 *fifo_byte = (u8 *)&fifo_word;
 708		unsigned int bytes_to_read;
 709		unsigned int j;
 710
 711		bytes_to_read = min(bytes_per_fifo_word, rx_bytes - i);
 712		ioread32_rep(se->base + SE_GENI_RX_FIFOn, &fifo_word, 1);
 713		for (j = 0; j < bytes_to_read; j++)
 714			rx_buf[i++] = fifo_byte[j];
 715	}
 716	mas->rx_rem_bytes -= rx_bytes;
 717}
 718
 719static void setup_fifo_xfer(struct spi_transfer *xfer,
 720				struct spi_geni_master *mas,
 721				u16 mode, struct spi_master *spi)
 722{
 723	u32 m_cmd = 0;
 724	u32 len;
 725	struct geni_se *se = &mas->se;
 726	int ret;
 727
 728	/*
 729	 * Ensure that our interrupt handler isn't still running from some
 730	 * prior command before we start messing with the hardware behind
 731	 * its back.  We don't need to _keep_ the lock here since we're only
 732	 * worried about racing with out interrupt handler.  The SPI core
 733	 * already handles making sure that we're not trying to do two
 734	 * transfers at once or setting a chip select and doing a transfer
 735	 * concurrently.
 736	 *
 737	 * NOTE: we actually _can't_ hold the lock here because possibly we
 738	 * might call clk_set_rate() which needs to be able to sleep.
 739	 */
 740	spin_lock_irq(&mas->lock);
 741	spin_unlock_irq(&mas->lock);
 742
 743	if (xfer->bits_per_word != mas->cur_bits_per_word) {
 744		spi_setup_word_len(mas, mode, xfer->bits_per_word);
 745		mas->cur_bits_per_word = xfer->bits_per_word;
 746	}
 747
 748	/* Speed and bits per word can be overridden per transfer */
 749	ret = geni_spi_set_clock_and_bw(mas, xfer->speed_hz);
 750	if (ret)
 751		return;
 752
 753	mas->tx_rem_bytes = 0;
 754	mas->rx_rem_bytes = 0;
 755
 756	if (!(mas->cur_bits_per_word % MIN_WORD_LEN))
 757		len = xfer->len * BITS_PER_BYTE / mas->cur_bits_per_word;
 758	else
 759		len = xfer->len / (mas->cur_bits_per_word / BITS_PER_BYTE + 1);
 760	len &= TRANS_LEN_MSK;
 761
 762	mas->cur_xfer = xfer;
 763	if (xfer->tx_buf) {
 764		m_cmd |= SPI_TX_ONLY;
 765		mas->tx_rem_bytes = xfer->len;
 766		writel(len, se->base + SE_SPI_TX_TRANS_LEN);
 767	}
 768
 769	if (xfer->rx_buf) {
 770		m_cmd |= SPI_RX_ONLY;
 771		writel(len, se->base + SE_SPI_RX_TRANS_LEN);
 772		mas->rx_rem_bytes = xfer->len;
 773	}
 774
 775	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 776	 * Lock around right before we start the transfer since our
 777	 * interrupt could come in at any time now.
 778	 */
 779	spin_lock_irq(&mas->lock);
 780	geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION);
 781	if (m_cmd & SPI_TX_ONLY) {
 
 
 
 
 
 
 
 
 782		if (geni_spi_handle_tx(mas))
 783			writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG);
 784	}
 
 785	spin_unlock_irq(&mas->lock);
 
 786}
 787
 788static int spi_geni_transfer_one(struct spi_master *spi,
 789				struct spi_device *slv,
 790				struct spi_transfer *xfer)
 791{
 792	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 
 793
 794	if (spi_geni_is_abort_still_pending(mas))
 795		return -EBUSY;
 796
 797	/* Terminate and return success for 0 byte length transfer */
 798	if (!xfer->len)
 799		return 0;
 800
 801	if (mas->cur_xfer_mode == GENI_SE_FIFO) {
 802		setup_fifo_xfer(xfer, mas, slv->mode, spi);
 803		return 1;
 
 
 
 804	}
 805	return setup_gsi_xfer(xfer, mas, slv, spi);
 806}
 807
 808static irqreturn_t geni_spi_isr(int irq, void *data)
 809{
 810	struct spi_master *spi = data;
 811	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 812	struct geni_se *se = &mas->se;
 813	u32 m_irq;
 814
 815	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
 816	if (!m_irq)
 817		return IRQ_NONE;
 818
 819	if (m_irq & (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |
 820		     M_RX_FIFO_RD_ERR_EN | M_RX_FIFO_WR_ERR_EN |
 821		     M_TX_FIFO_RD_ERR_EN | M_TX_FIFO_WR_ERR_EN))
 822		dev_warn(mas->dev, "Unexpected IRQ err status %#010x\n", m_irq);
 823
 824	spin_lock(&mas->lock);
 825
 826	if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN))
 827		geni_spi_handle_rx(mas);
 
 828
 829	if (m_irq & M_TX_FIFO_WATERMARK_EN)
 830		geni_spi_handle_tx(mas);
 831
 832	if (m_irq & M_CMD_DONE_EN) {
 833		if (mas->cur_xfer) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 834			spi_finalize_current_transfer(spi);
 835			mas->cur_xfer = NULL;
 836			/*
 837			 * If this happens, then a CMD_DONE came before all the
 838			 * Tx buffer bytes were sent out. This is unusual, log
 839			 * this condition and disable the WM interrupt to
 840			 * prevent the system from stalling due an interrupt
 841			 * storm.
 842			 *
 843			 * If this happens when all Rx bytes haven't been
 844			 * received, log the condition. The only known time
 845			 * this can happen is if bits_per_word != 8 and some
 846			 * registers that expect xfer lengths in num spi_words
 847			 * weren't written correctly.
 848			 */
 849			if (mas->tx_rem_bytes) {
 850				writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 851				dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n",
 852					mas->tx_rem_bytes, mas->cur_bits_per_word);
 853			}
 854			if (mas->rx_rem_bytes)
 855				dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n",
 856					mas->rx_rem_bytes, mas->cur_bits_per_word);
 857		} else {
 858			complete(&mas->cs_done);
 859		}
 860	}
 861
 862	if (m_irq & M_CMD_CANCEL_EN)
 863		complete(&mas->cancel_done);
 864	if (m_irq & M_CMD_ABORT_EN)
 865		complete(&mas->abort_done);
 866
 867	/*
 868	 * It's safe or a good idea to Ack all of our interrupts at the end
 869	 * of the function. Specifically:
 870	 * - M_CMD_DONE_EN / M_RX_FIFO_LAST_EN: Edge triggered interrupts and
 871	 *   clearing Acks. Clearing at the end relies on nobody else having
 872	 *   started a new transfer yet or else we could be clearing _their_
 873	 *   done bit, but everyone grabs the spinlock before starting a new
 874	 *   transfer.
 875	 * - M_RX_FIFO_WATERMARK_EN / M_TX_FIFO_WATERMARK_EN: These appear
 876	 *   to be "latched level" interrupts so it's important to clear them
 877	 *   _after_ you've handled the condition and always safe to do so
 878	 *   since they'll re-assert if they're still happening.
 879	 */
 880	writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR);
 881
 882	spin_unlock(&mas->lock);
 883
 884	return IRQ_HANDLED;
 885}
 886
 887static int spi_geni_probe(struct platform_device *pdev)
 888{
 889	int ret, irq;
 890	struct spi_master *spi;
 891	struct spi_geni_master *mas;
 892	void __iomem *base;
 893	struct clk *clk;
 894	struct device *dev = &pdev->dev;
 895
 896	irq = platform_get_irq(pdev, 0);
 897	if (irq < 0)
 898		return irq;
 899
 900	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
 901	if (ret)
 902		return dev_err_probe(dev, ret, "could not set DMA mask\n");
 903
 904	base = devm_platform_ioremap_resource(pdev, 0);
 905	if (IS_ERR(base))
 906		return PTR_ERR(base);
 907
 908	clk = devm_clk_get(dev, "se");
 909	if (IS_ERR(clk))
 910		return PTR_ERR(clk);
 911
 912	spi = devm_spi_alloc_master(dev, sizeof(*mas));
 913	if (!spi)
 914		return -ENOMEM;
 915
 916	platform_set_drvdata(pdev, spi);
 917	mas = spi_master_get_devdata(spi);
 918	mas->irq = irq;
 919	mas->dev = dev;
 920	mas->se.dev = dev;
 921	mas->se.wrapper = dev_get_drvdata(dev->parent);
 922	mas->se.base = base;
 923	mas->se.clk = clk;
 924
 925	ret = devm_pm_opp_set_clkname(&pdev->dev, "se");
 926	if (ret)
 927		return ret;
 928	/* OPP table is optional */
 929	ret = devm_pm_opp_of_add_table(&pdev->dev);
 930	if (ret && ret != -ENODEV) {
 931		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
 932		return ret;
 933	}
 934
 935	spi->bus_num = -1;
 936	spi->dev.of_node = dev->of_node;
 937	spi->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_CS_HIGH;
 938	spi->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
 939	spi->num_chipselect = 4;
 940	spi->max_speed_hz = 50000000;
 
 941	spi->prepare_message = spi_geni_prepare_message;
 942	spi->transfer_one = spi_geni_transfer_one;
 943	spi->can_dma = geni_can_dma;
 944	spi->dma_map_dev = dev->parent;
 945	spi->auto_runtime_pm = true;
 946	spi->handle_err = spi_geni_handle_err;
 947	spi->use_gpio_descriptors = true;
 948
 949	init_completion(&mas->cs_done);
 950	init_completion(&mas->cancel_done);
 951	init_completion(&mas->abort_done);
 
 
 952	spin_lock_init(&mas->lock);
 953	pm_runtime_use_autosuspend(&pdev->dev);
 954	pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
 955	pm_runtime_enable(dev);
 956
 957	ret = geni_icc_get(&mas->se, NULL);
 958	if (ret)
 959		goto spi_geni_probe_runtime_disable;
 
 
 
 
 
 
 
 
 
 
 960	/* Set the bus quota to a reasonable value for register access */
 961	mas->se.icc_paths[GENI_TO_CORE].avg_bw = Bps_to_icc(CORE_2X_50_MHZ);
 962	mas->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
 963
 964	ret = geni_icc_set_bw(&mas->se);
 965	if (ret)
 966		goto spi_geni_probe_runtime_disable;
 967
 968	ret = spi_geni_init(mas);
 969	if (ret)
 970		goto spi_geni_probe_runtime_disable;
 971
 972	/*
 973	 * check the mode supported and set_cs for fifo mode only
 974	 * for dma (gsi) mode, the gsi will set cs based on params passed in
 975	 * TRE
 976	 */
 977	if (mas->cur_xfer_mode == GENI_SE_FIFO)
 978		spi->set_cs = spi_geni_set_cs;
 979
 980	ret = request_irq(mas->irq, geni_spi_isr, 0, dev_name(dev), spi);
 981	if (ret)
 982		goto spi_geni_release_dma;
 
 
 983
 984	ret = spi_register_master(spi);
 985	if (ret)
 986		goto spi_geni_probe_free_irq;
 987
 988	return 0;
 989spi_geni_probe_free_irq:
 990	free_irq(mas->irq, spi);
 991spi_geni_release_dma:
 992	spi_geni_release_dma_chan(mas);
 993spi_geni_probe_runtime_disable:
 994	pm_runtime_disable(dev);
 995	return ret;
 996}
 997
 998static int spi_geni_remove(struct platform_device *pdev)
 999{
1000	struct spi_master *spi = platform_get_drvdata(pdev);
1001	struct spi_geni_master *mas = spi_master_get_devdata(spi);
1002
1003	/* Unregister _before_ disabling pm_runtime() so we stop transfers */
1004	spi_unregister_master(spi);
1005
1006	spi_geni_release_dma_chan(mas);
1007
1008	free_irq(mas->irq, spi);
1009	pm_runtime_disable(&pdev->dev);
1010	return 0;
1011}
1012
1013static int __maybe_unused spi_geni_runtime_suspend(struct device *dev)
1014{
1015	struct spi_master *spi = dev_get_drvdata(dev);
1016	struct spi_geni_master *mas = spi_master_get_devdata(spi);
1017	int ret;
1018
1019	/* Drop the performance state vote */
1020	dev_pm_opp_set_rate(dev, 0);
1021
1022	ret = geni_se_resources_off(&mas->se);
1023	if (ret)
1024		return ret;
1025
1026	return geni_icc_disable(&mas->se);
1027}
1028
1029static int __maybe_unused spi_geni_runtime_resume(struct device *dev)
1030{
1031	struct spi_master *spi = dev_get_drvdata(dev);
1032	struct spi_geni_master *mas = spi_master_get_devdata(spi);
1033	int ret;
1034
1035	ret = geni_icc_enable(&mas->se);
1036	if (ret)
1037		return ret;
1038
1039	ret = geni_se_resources_on(&mas->se);
1040	if (ret)
1041		return ret;
1042
1043	return dev_pm_opp_set_rate(mas->dev, mas->cur_sclk_hz);
1044}
1045
1046static int __maybe_unused spi_geni_suspend(struct device *dev)
1047{
1048	struct spi_master *spi = dev_get_drvdata(dev);
1049	int ret;
1050
1051	ret = spi_master_suspend(spi);
1052	if (ret)
1053		return ret;
1054
1055	ret = pm_runtime_force_suspend(dev);
1056	if (ret)
1057		spi_master_resume(spi);
1058
1059	return ret;
1060}
1061
1062static int __maybe_unused spi_geni_resume(struct device *dev)
1063{
1064	struct spi_master *spi = dev_get_drvdata(dev);
1065	int ret;
1066
1067	ret = pm_runtime_force_resume(dev);
1068	if (ret)
1069		return ret;
1070
1071	ret = spi_master_resume(spi);
1072	if (ret)
1073		pm_runtime_force_suspend(dev);
1074
1075	return ret;
1076}
1077
1078static const struct dev_pm_ops spi_geni_pm_ops = {
1079	SET_RUNTIME_PM_OPS(spi_geni_runtime_suspend,
1080					spi_geni_runtime_resume, NULL)
1081	SET_SYSTEM_SLEEP_PM_OPS(spi_geni_suspend, spi_geni_resume)
1082};
1083
1084static const struct of_device_id spi_geni_dt_match[] = {
1085	{ .compatible = "qcom,geni-spi" },
1086	{}
1087};
1088MODULE_DEVICE_TABLE(of, spi_geni_dt_match);
1089
1090static struct platform_driver spi_geni_driver = {
1091	.probe  = spi_geni_probe,
1092	.remove = spi_geni_remove,
1093	.driver = {
1094		.name = "geni_spi",
1095		.pm = &spi_geni_pm_ops,
1096		.of_match_table = spi_geni_dt_match,
1097	},
1098};
1099module_platform_driver(spi_geni_driver);
1100
1101MODULE_DESCRIPTION("SPI driver for GENI based QUP cores");
1102MODULE_LICENSE("GPL v2");
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0
   2// Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
   3
   4#include <linux/clk.h>
   5#include <linux/dmaengine.h>
   6#include <linux/dma-mapping.h>
   7#include <linux/dma/qcom-gpi-dma.h>
   8#include <linux/interrupt.h>
   9#include <linux/io.h>
  10#include <linux/log2.h>
  11#include <linux/module.h>
  12#include <linux/platform_device.h>
  13#include <linux/pm_opp.h>
  14#include <linux/pm_runtime.h>
  15#include <linux/property.h>
  16#include <linux/soc/qcom/geni-se.h>
  17#include <linux/spi/spi.h>
  18#include <linux/spinlock.h>
  19
  20/* SPI SE specific registers and respective register fields */
  21#define SE_SPI_CPHA		0x224
  22#define CPHA			BIT(0)
  23
  24#define SE_SPI_LOOPBACK		0x22c
  25#define LOOPBACK_ENABLE		0x1
  26#define NORMAL_MODE		0x0
  27#define LOOPBACK_MSK		GENMASK(1, 0)
  28
  29#define SE_SPI_CPOL		0x230
  30#define CPOL			BIT(2)
  31
  32#define SE_SPI_DEMUX_OUTPUT_INV	0x24c
  33#define CS_DEMUX_OUTPUT_INV_MSK	GENMASK(3, 0)
  34
  35#define SE_SPI_DEMUX_SEL	0x250
  36#define CS_DEMUX_OUTPUT_SEL	GENMASK(3, 0)
  37
  38#define SE_SPI_TRANS_CFG	0x25c
  39#define CS_TOGGLE		BIT(1)
  40
  41#define SE_SPI_WORD_LEN		0x268
  42#define WORD_LEN_MSK		GENMASK(9, 0)
  43#define MIN_WORD_LEN		4
  44
  45#define SE_SPI_TX_TRANS_LEN	0x26c
  46#define SE_SPI_RX_TRANS_LEN	0x270
  47#define TRANS_LEN_MSK		GENMASK(23, 0)
  48
  49#define SE_SPI_PRE_POST_CMD_DLY	0x274
  50
  51#define SE_SPI_DELAY_COUNTERS	0x278
  52#define SPI_INTER_WORDS_DELAY_MSK	GENMASK(9, 0)
  53#define SPI_CS_CLK_DELAY_MSK		GENMASK(19, 10)
  54#define SPI_CS_CLK_DELAY_SHFT		10
  55
  56#define SE_SPI_SLAVE_EN				(0x2BC)
  57#define SPI_SLAVE_EN				BIT(0)
  58
  59/* M_CMD OP codes for SPI */
  60#define SPI_TX_ONLY		1
  61#define SPI_RX_ONLY		2
  62#define SPI_TX_RX		7
  63#define SPI_CS_ASSERT		8
  64#define SPI_CS_DEASSERT		9
  65#define SPI_SCK_ONLY		10
  66/* M_CMD params for SPI */
  67#define SPI_PRE_CMD_DELAY	BIT(0)
  68#define TIMESTAMP_BEFORE	BIT(1)
  69#define FRAGMENTATION		BIT(2)
  70#define TIMESTAMP_AFTER		BIT(3)
  71#define POST_CMD_DELAY		BIT(4)
  72
  73#define GSI_LOOPBACK_EN		BIT(0)
  74#define GSI_CS_TOGGLE		BIT(3)
  75#define GSI_CPHA		BIT(4)
  76#define GSI_CPOL		BIT(5)
  77
  78struct spi_geni_master {
  79	struct geni_se se;
  80	struct device *dev;
  81	u32 tx_fifo_depth;
  82	u32 fifo_width_bits;
  83	u32 tx_wm;
  84	u32 last_mode;
  85	unsigned long cur_speed_hz;
  86	unsigned long cur_sclk_hz;
  87	unsigned int cur_bits_per_word;
  88	unsigned int tx_rem_bytes;
  89	unsigned int rx_rem_bytes;
  90	const struct spi_transfer *cur_xfer;
  91	struct completion cs_done;
  92	struct completion cancel_done;
  93	struct completion abort_done;
  94	struct completion tx_reset_done;
  95	struct completion rx_reset_done;
  96	unsigned int oversampling;
  97	spinlock_t lock;
  98	int irq;
  99	bool cs_flag;
 100	bool abort_failed;
 101	struct dma_chan *tx;
 102	struct dma_chan *rx;
 103	int cur_xfer_mode;
 104};
 105
 106static void spi_slv_setup(struct spi_geni_master *mas)
 107{
 108	struct geni_se *se = &mas->se;
 109
 110	writel(SPI_SLAVE_EN, se->base + SE_SPI_SLAVE_EN);
 111	writel(GENI_IO_MUX_0_EN, se->base + GENI_OUTPUT_CTRL);
 112	writel(START_TRIGGER, se->base + SE_GENI_CFG_SEQ_START);
 113	dev_dbg(mas->dev, "spi slave setup done\n");
 114}
 115
 116static int get_spi_clk_cfg(unsigned int speed_hz,
 117			struct spi_geni_master *mas,
 118			unsigned int *clk_idx,
 119			unsigned int *clk_div)
 120{
 121	unsigned long sclk_freq;
 122	unsigned int actual_hz;
 123	int ret;
 124
 125	ret = geni_se_clk_freq_match(&mas->se,
 126				speed_hz * mas->oversampling,
 127				clk_idx, &sclk_freq, false);
 128	if (ret) {
 129		dev_err(mas->dev, "Failed(%d) to find src clk for %dHz\n",
 130							ret, speed_hz);
 131		return ret;
 132	}
 133
 134	*clk_div = DIV_ROUND_UP(sclk_freq, mas->oversampling * speed_hz);
 135	actual_hz = sclk_freq / (mas->oversampling * *clk_div);
 136
 137	dev_dbg(mas->dev, "req %u=>%u sclk %lu, idx %d, div %d\n", speed_hz,
 138				actual_hz, sclk_freq, *clk_idx, *clk_div);
 139	ret = dev_pm_opp_set_rate(mas->dev, sclk_freq);
 140	if (ret)
 141		dev_err(mas->dev, "dev_pm_opp_set_rate failed %d\n", ret);
 142	else
 143		mas->cur_sclk_hz = sclk_freq;
 144
 145	return ret;
 146}
 147
 148static void handle_se_timeout(struct spi_controller *spi,
 149			      struct spi_message *msg)
 150{
 151	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 152	unsigned long time_left;
 153	struct geni_se *se = &mas->se;
 154	const struct spi_transfer *xfer;
 155
 156	spin_lock_irq(&mas->lock);
 157	if (mas->cur_xfer_mode == GENI_SE_FIFO)
 158		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 159
 160	xfer = mas->cur_xfer;
 161	mas->cur_xfer = NULL;
 162
 163	if (spi->target) {
 164		/*
 165		 * skip CMD Cancel sequnece since spi target
 166		 * doesn`t support CMD Cancel sequnece
 167		 */
 168		spin_unlock_irq(&mas->lock);
 169		goto reset_if_dma;
 170	}
 171
 172	reinit_completion(&mas->cancel_done);
 173	geni_se_cancel_m_cmd(se);
 174	spin_unlock_irq(&mas->lock);
 175
 176	time_left = wait_for_completion_timeout(&mas->cancel_done, HZ);
 177	if (time_left)
 178		goto reset_if_dma;
 179
 180	spin_lock_irq(&mas->lock);
 181	reinit_completion(&mas->abort_done);
 182	geni_se_abort_m_cmd(se);
 183	spin_unlock_irq(&mas->lock);
 184
 185	time_left = wait_for_completion_timeout(&mas->abort_done, HZ);
 186	if (!time_left) {
 187		dev_err(mas->dev, "Failed to cancel/abort m_cmd\n");
 188
 189		/*
 190		 * No need for a lock since SPI core has a lock and we never
 191		 * access this from an interrupt.
 192		 */
 193		mas->abort_failed = true;
 194	}
 195
 196reset_if_dma:
 197	if (mas->cur_xfer_mode == GENI_SE_DMA) {
 198		if (xfer) {
 199			if (xfer->tx_buf) {
 200				spin_lock_irq(&mas->lock);
 201				reinit_completion(&mas->tx_reset_done);
 202				writel(1, se->base + SE_DMA_TX_FSM_RST);
 203				spin_unlock_irq(&mas->lock);
 204				time_left = wait_for_completion_timeout(&mas->tx_reset_done, HZ);
 205				if (!time_left)
 206					dev_err(mas->dev, "DMA TX RESET failed\n");
 207			}
 208			if (xfer->rx_buf) {
 209				spin_lock_irq(&mas->lock);
 210				reinit_completion(&mas->rx_reset_done);
 211				writel(1, se->base + SE_DMA_RX_FSM_RST);
 212				spin_unlock_irq(&mas->lock);
 213				time_left = wait_for_completion_timeout(&mas->rx_reset_done, HZ);
 214				if (!time_left)
 215					dev_err(mas->dev, "DMA RX RESET failed\n");
 216			}
 217		} else {
 218			/*
 219			 * This can happen if a timeout happened and we had to wait
 220			 * for lock in this function because isr was holding the lock
 221			 * and handling transfer completion at that time.
 222			 */
 223			dev_warn(mas->dev, "Cancel/Abort on completed SPI transfer\n");
 224		}
 225	}
 226}
 227
 228static void handle_gpi_timeout(struct spi_controller *spi, struct spi_message *msg)
 229{
 230	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 231
 232	dmaengine_terminate_sync(mas->tx);
 233	dmaengine_terminate_sync(mas->rx);
 234}
 235
 236static void spi_geni_handle_err(struct spi_controller *spi, struct spi_message *msg)
 237{
 238	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 239
 240	switch (mas->cur_xfer_mode) {
 241	case GENI_SE_FIFO:
 242	case GENI_SE_DMA:
 243		handle_se_timeout(spi, msg);
 244		break;
 245	case GENI_GPI_DMA:
 246		handle_gpi_timeout(spi, msg);
 247		break;
 248	default:
 249		dev_err(mas->dev, "Abort on Mode:%d not supported", mas->cur_xfer_mode);
 250	}
 251}
 252
 253static bool spi_geni_is_abort_still_pending(struct spi_geni_master *mas)
 254{
 255	struct geni_se *se = &mas->se;
 256	u32 m_irq, m_irq_en;
 257
 258	if (!mas->abort_failed)
 259		return false;
 260
 261	/*
 262	 * The only known case where a transfer times out and then a cancel
 263	 * times out then an abort times out is if something is blocking our
 264	 * interrupt handler from running.  Avoid starting any new transfers
 265	 * until that sorts itself out.
 266	 */
 267	spin_lock_irq(&mas->lock);
 268	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
 269	m_irq_en = readl(se->base + SE_GENI_M_IRQ_EN);
 270	spin_unlock_irq(&mas->lock);
 271
 272	if (m_irq & m_irq_en) {
 273		dev_err(mas->dev, "Interrupts pending after abort: %#010x\n",
 274			m_irq & m_irq_en);
 275		return true;
 276	}
 277
 278	/*
 279	 * If we're here the problem resolved itself so no need to check more
 280	 * on future transfers.
 281	 */
 282	mas->abort_failed = false;
 283
 284	return false;
 285}
 286
 287static void spi_geni_set_cs(struct spi_device *slv, bool set_flag)
 288{
 289	struct spi_geni_master *mas = spi_controller_get_devdata(slv->controller);
 290	struct spi_controller *spi = dev_get_drvdata(mas->dev);
 291	struct geni_se *se = &mas->se;
 292	unsigned long time_left;
 293
 294	if (!(slv->mode & SPI_CS_HIGH))
 295		set_flag = !set_flag;
 296
 297	if (set_flag == mas->cs_flag)
 298		return;
 299
 300	pm_runtime_get_sync(mas->dev);
 301
 302	if (spi_geni_is_abort_still_pending(mas)) {
 303		dev_err(mas->dev, "Can't set chip select\n");
 304		goto exit;
 305	}
 306
 307	spin_lock_irq(&mas->lock);
 308	if (mas->cur_xfer) {
 309		dev_err(mas->dev, "Can't set CS when prev xfer running\n");
 310		spin_unlock_irq(&mas->lock);
 311		goto exit;
 312	}
 313
 314	mas->cs_flag = set_flag;
 315	/* set xfer_mode to FIFO to complete cs_done in isr */
 316	mas->cur_xfer_mode = GENI_SE_FIFO;
 317	geni_se_select_mode(se, mas->cur_xfer_mode);
 318
 319	reinit_completion(&mas->cs_done);
 320	if (set_flag)
 321		geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0);
 322	else
 323		geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0);
 324	spin_unlock_irq(&mas->lock);
 325
 326	time_left = wait_for_completion_timeout(&mas->cs_done, HZ);
 327	if (!time_left) {
 328		dev_warn(mas->dev, "Timeout setting chip select\n");
 329		handle_se_timeout(spi, NULL);
 330	}
 331
 332exit:
 333	pm_runtime_put(mas->dev);
 334}
 335
 336static void spi_setup_word_len(struct spi_geni_master *mas, u16 mode,
 337					unsigned int bits_per_word)
 338{
 339	unsigned int pack_words;
 340	bool msb_first = (mode & SPI_LSB_FIRST) ? false : true;
 341	struct geni_se *se = &mas->se;
 342	u32 word_len;
 343
 344	/*
 345	 * If bits_per_word isn't a byte aligned value, set the packing to be
 346	 * 1 SPI word per FIFO word.
 347	 */
 348	if (!(mas->fifo_width_bits % bits_per_word))
 349		pack_words = mas->fifo_width_bits / bits_per_word;
 350	else
 351		pack_words = 1;
 352	geni_se_config_packing(&mas->se, bits_per_word, pack_words, msb_first,
 353								true, true);
 354	word_len = (bits_per_word - MIN_WORD_LEN) & WORD_LEN_MSK;
 355	writel(word_len, se->base + SE_SPI_WORD_LEN);
 356}
 357
 358static int geni_spi_set_clock_and_bw(struct spi_geni_master *mas,
 359					unsigned long clk_hz)
 360{
 361	u32 clk_sel, m_clk_cfg, idx, div;
 362	struct geni_se *se = &mas->se;
 363	int ret;
 364
 365	if (clk_hz == mas->cur_speed_hz)
 366		return 0;
 367
 368	ret = get_spi_clk_cfg(clk_hz, mas, &idx, &div);
 369	if (ret) {
 370		dev_err(mas->dev, "Err setting clk to %lu: %d\n", clk_hz, ret);
 371		return ret;
 372	}
 373
 374	/*
 375	 * SPI core clock gets configured with the requested frequency
 376	 * or the frequency closer to the requested frequency.
 377	 * For that reason requested frequency is stored in the
 378	 * cur_speed_hz and referred in the consecutive transfer instead
 379	 * of calling clk_get_rate() API.
 380	 */
 381	mas->cur_speed_hz = clk_hz;
 382
 383	clk_sel = idx & CLK_SEL_MSK;
 384	m_clk_cfg = (div << CLK_DIV_SHFT) | SER_CLK_EN;
 385	writel(clk_sel, se->base + SE_GENI_CLK_SEL);
 386	writel(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG);
 387
 388	/* Set BW quota for CPU as driver supports FIFO mode only. */
 389	se->icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(mas->cur_speed_hz);
 390	ret = geni_icc_set_bw(se);
 391	if (ret)
 392		return ret;
 393
 394	return 0;
 395}
 396
 397static int setup_fifo_params(struct spi_device *spi_slv,
 398					struct spi_controller *spi)
 399{
 400	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 401	struct geni_se *se = &mas->se;
 402	u32 loopback_cfg = 0, cpol = 0, cpha = 0, demux_output_inv = 0;
 403	u32 demux_sel;
 404
 405	if (mas->last_mode != spi_slv->mode) {
 406		if (spi_slv->mode & SPI_LOOP)
 407			loopback_cfg = LOOPBACK_ENABLE;
 408
 409		if (spi_slv->mode & SPI_CPOL)
 410			cpol = CPOL;
 411
 412		if (spi_slv->mode & SPI_CPHA)
 413			cpha = CPHA;
 414
 415		if (spi_slv->mode & SPI_CS_HIGH)
 416			demux_output_inv = BIT(spi_get_chipselect(spi_slv, 0));
 417
 418		demux_sel = spi_get_chipselect(spi_slv, 0);
 419		mas->cur_bits_per_word = spi_slv->bits_per_word;
 420
 421		spi_setup_word_len(mas, spi_slv->mode, spi_slv->bits_per_word);
 422		writel(loopback_cfg, se->base + SE_SPI_LOOPBACK);
 423		writel(demux_sel, se->base + SE_SPI_DEMUX_SEL);
 424		writel(cpha, se->base + SE_SPI_CPHA);
 425		writel(cpol, se->base + SE_SPI_CPOL);
 426		writel(demux_output_inv, se->base + SE_SPI_DEMUX_OUTPUT_INV);
 427
 428		mas->last_mode = spi_slv->mode;
 429	}
 430
 431	return geni_spi_set_clock_and_bw(mas, spi_slv->max_speed_hz);
 432}
 433
 434static void
 435spi_gsi_callback_result(void *cb, const struct dmaengine_result *result)
 436{
 437	struct spi_controller *spi = cb;
 438
 439	spi->cur_msg->status = -EIO;
 440	if (result->result != DMA_TRANS_NOERROR) {
 441		dev_err(&spi->dev, "DMA txn failed: %d\n", result->result);
 442		spi_finalize_current_transfer(spi);
 443		return;
 444	}
 445
 446	if (!result->residue) {
 447		spi->cur_msg->status = 0;
 448		dev_dbg(&spi->dev, "DMA txn completed\n");
 449	} else {
 450		dev_err(&spi->dev, "DMA xfer has pending: %d\n", result->residue);
 451	}
 452
 453	spi_finalize_current_transfer(spi);
 454}
 455
 456static int setup_gsi_xfer(struct spi_transfer *xfer, struct spi_geni_master *mas,
 457			  struct spi_device *spi_slv, struct spi_controller *spi)
 458{
 459	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
 460	struct dma_slave_config config = {};
 461	struct gpi_spi_config peripheral = {};
 462	struct dma_async_tx_descriptor *tx_desc, *rx_desc;
 463	int ret;
 464
 465	config.peripheral_config = &peripheral;
 466	config.peripheral_size = sizeof(peripheral);
 467	peripheral.set_config = true;
 468
 469	if (xfer->bits_per_word != mas->cur_bits_per_word ||
 470	    xfer->speed_hz != mas->cur_speed_hz) {
 471		mas->cur_bits_per_word = xfer->bits_per_word;
 472		mas->cur_speed_hz = xfer->speed_hz;
 473	}
 474
 475	if (xfer->tx_buf && xfer->rx_buf) {
 476		peripheral.cmd = SPI_DUPLEX;
 477	} else if (xfer->tx_buf) {
 478		peripheral.cmd = SPI_TX;
 479		peripheral.rx_len = 0;
 480	} else if (xfer->rx_buf) {
 481		peripheral.cmd = SPI_RX;
 482		if (!(mas->cur_bits_per_word % MIN_WORD_LEN)) {
 483			peripheral.rx_len = ((xfer->len << 3) / mas->cur_bits_per_word);
 484		} else {
 485			int bytes_per_word = (mas->cur_bits_per_word / BITS_PER_BYTE) + 1;
 486
 487			peripheral.rx_len = (xfer->len / bytes_per_word);
 488		}
 489	}
 490
 491	peripheral.loopback_en = !!(spi_slv->mode & SPI_LOOP);
 492	peripheral.clock_pol_high = !!(spi_slv->mode & SPI_CPOL);
 493	peripheral.data_pol_high = !!(spi_slv->mode & SPI_CPHA);
 494	peripheral.cs = spi_get_chipselect(spi_slv, 0);
 495	peripheral.pack_en = true;
 496	peripheral.word_len = xfer->bits_per_word - MIN_WORD_LEN;
 497
 498	ret = get_spi_clk_cfg(mas->cur_speed_hz, mas,
 499			      &peripheral.clk_src, &peripheral.clk_div);
 500	if (ret) {
 501		dev_err(mas->dev, "Err in get_spi_clk_cfg() :%d\n", ret);
 502		return ret;
 503	}
 504
 505	if (!xfer->cs_change) {
 506		if (!list_is_last(&xfer->transfer_list, &spi->cur_msg->transfers))
 507			peripheral.fragmentation = FRAGMENTATION;
 508	}
 509
 510	if (peripheral.cmd & SPI_RX) {
 511		dmaengine_slave_config(mas->rx, &config);
 512		rx_desc = dmaengine_prep_slave_sg(mas->rx, xfer->rx_sg.sgl, xfer->rx_sg.nents,
 513						  DMA_DEV_TO_MEM, flags);
 514		if (!rx_desc) {
 515			dev_err(mas->dev, "Err setting up rx desc\n");
 516			return -EIO;
 517		}
 518	}
 519
 520	/*
 521	 * Prepare the TX always, even for RX or tx_buf being null, we would
 522	 * need TX to be prepared per GSI spec
 523	 */
 524	dmaengine_slave_config(mas->tx, &config);
 525	tx_desc = dmaengine_prep_slave_sg(mas->tx, xfer->tx_sg.sgl, xfer->tx_sg.nents,
 526					  DMA_MEM_TO_DEV, flags);
 527	if (!tx_desc) {
 528		dev_err(mas->dev, "Err setting up tx desc\n");
 529		return -EIO;
 530	}
 531
 532	tx_desc->callback_result = spi_gsi_callback_result;
 533	tx_desc->callback_param = spi;
 534
 535	if (peripheral.cmd & SPI_RX)
 536		dmaengine_submit(rx_desc);
 537	dmaengine_submit(tx_desc);
 538
 539	if (peripheral.cmd & SPI_RX)
 540		dma_async_issue_pending(mas->rx);
 541
 542	dma_async_issue_pending(mas->tx);
 543	return 1;
 544}
 545
 546static u32 get_xfer_len_in_words(struct spi_transfer *xfer,
 547				struct spi_geni_master *mas)
 548{
 549	u32 len;
 550
 551	if (!(mas->cur_bits_per_word % MIN_WORD_LEN))
 552		len = xfer->len * BITS_PER_BYTE / mas->cur_bits_per_word;
 553	else
 554		len = xfer->len / (mas->cur_bits_per_word / BITS_PER_BYTE + 1);
 555	len &= TRANS_LEN_MSK;
 556
 557	return len;
 558}
 559
 560static bool geni_can_dma(struct spi_controller *ctlr,
 561			 struct spi_device *slv, struct spi_transfer *xfer)
 562{
 563	struct spi_geni_master *mas = spi_controller_get_devdata(slv->controller);
 564	u32 len, fifo_size;
 565
 566	if (mas->cur_xfer_mode == GENI_GPI_DMA)
 567		return true;
 568
 569	/* Set SE DMA mode for SPI target. */
 570	if (ctlr->target)
 571		return true;
 572
 573	len = get_xfer_len_in_words(xfer, mas);
 574	fifo_size = mas->tx_fifo_depth * mas->fifo_width_bits / mas->cur_bits_per_word;
 575
 576	if (len > fifo_size)
 577		return true;
 578	else
 579		return false;
 580}
 581
 582static int spi_geni_prepare_message(struct spi_controller *spi,
 583				    struct spi_message *spi_msg)
 584{
 585	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 586	int ret;
 587
 588	switch (mas->cur_xfer_mode) {
 589	case GENI_SE_FIFO:
 590	case GENI_SE_DMA:
 591		if (spi_geni_is_abort_still_pending(mas))
 592			return -EBUSY;
 593		ret = setup_fifo_params(spi_msg->spi, spi);
 594		if (ret)
 595			dev_err(mas->dev, "Couldn't select mode %d\n", ret);
 596		return ret;
 597
 598	case GENI_GPI_DMA:
 599		/* nothing to do for GPI DMA */
 600		return 0;
 601	}
 602
 603	dev_err(mas->dev, "Mode not supported %d", mas->cur_xfer_mode);
 604	return -EINVAL;
 605}
 606
 607static void spi_geni_release_dma_chan(void *data)
 608{
 609	struct spi_geni_master *mas = data;
 610
 611	if (mas->rx) {
 612		dma_release_channel(mas->rx);
 613		mas->rx = NULL;
 614	}
 615
 616	if (mas->tx) {
 617		dma_release_channel(mas->tx);
 618		mas->tx = NULL;
 619	}
 620}
 621
 622static int spi_geni_grab_gpi_chan(struct spi_geni_master *mas)
 623{
 624	int ret;
 625
 626	mas->tx = dma_request_chan(mas->dev, "tx");
 627	if (IS_ERR(mas->tx)) {
 628		ret = dev_err_probe(mas->dev, PTR_ERR(mas->tx),
 629				    "Failed to get tx DMA ch\n");
 630		goto err_tx;
 631	}
 632
 633	mas->rx = dma_request_chan(mas->dev, "rx");
 634	if (IS_ERR(mas->rx)) {
 635		ret = dev_err_probe(mas->dev, PTR_ERR(mas->rx),
 636				    "Failed to get rx DMA ch\n");
 637		goto err_rx;
 638	}
 639
 640	ret = devm_add_action_or_reset(mas->dev, spi_geni_release_dma_chan, mas);
 641	if (ret) {
 642		dev_err(mas->dev, "Unable to add action.\n");
 643		return ret;
 644	}
 645
 646	return 0;
 647
 648err_rx:
 649	mas->rx = NULL;
 650	dma_release_channel(mas->tx);
 651err_tx:
 652	mas->tx = NULL;
 653	return ret;
 654}
 655
 
 
 
 
 
 
 
 
 
 
 
 
 
 656static int spi_geni_init(struct spi_geni_master *mas)
 657{
 658	struct spi_controller *spi = dev_get_drvdata(mas->dev);
 659	struct geni_se *se = &mas->se;
 660	unsigned int proto, major, minor, ver;
 661	u32 spi_tx_cfg, fifo_disable;
 662	int ret = -ENXIO;
 663
 664	pm_runtime_get_sync(mas->dev);
 665
 666	proto = geni_se_read_proto(se);
 667
 668	if (spi->target) {
 669		if (proto != GENI_SE_SPI_SLAVE) {
 670			dev_err(mas->dev, "Invalid proto %d\n", proto);
 671			goto out_pm;
 672		}
 673		spi_slv_setup(mas);
 674	} else if (proto != GENI_SE_SPI) {
 675		dev_err(mas->dev, "Invalid proto %d\n", proto);
 676		goto out_pm;
 677	}
 678	mas->tx_fifo_depth = geni_se_get_tx_fifo_depth(se);
 679
 680	/* Width of Tx and Rx FIFO is same */
 681	mas->fifo_width_bits = geni_se_get_tx_fifo_width(se);
 682
 683	/*
 684	 * Hardware programming guide suggests to configure
 685	 * RX FIFO RFR level to fifo_depth-2.
 686	 */
 687	geni_se_init(se, mas->tx_fifo_depth - 3, mas->tx_fifo_depth - 2);
 688	/* Transmit an entire FIFO worth of data per IRQ */
 689	mas->tx_wm = 1;
 690	ver = geni_se_get_qup_hw_version(se);
 691	major = GENI_SE_VERSION_MAJOR(ver);
 692	minor = GENI_SE_VERSION_MINOR(ver);
 693
 694	if (major == 1 && minor == 0)
 695		mas->oversampling = 2;
 696	else
 697		mas->oversampling = 1;
 698
 699	fifo_disable = readl(se->base + GENI_IF_DISABLE_RO) & FIFO_IF_DISABLE;
 700	switch (fifo_disable) {
 701	case 1:
 702		ret = spi_geni_grab_gpi_chan(mas);
 703		if (!ret) { /* success case */
 704			mas->cur_xfer_mode = GENI_GPI_DMA;
 705			geni_se_select_mode(se, GENI_GPI_DMA);
 706			dev_dbg(mas->dev, "Using GPI DMA mode for SPI\n");
 707			break;
 708		} else if (ret == -EPROBE_DEFER) {
 709			goto out_pm;
 710		}
 711		/*
 712		 * in case of failure to get gpi dma channel, we can still do the
 713		 * FIFO mode, so fallthrough
 714		 */
 715		dev_warn(mas->dev, "FIFO mode disabled, but couldn't get DMA, fall back to FIFO mode\n");
 716		fallthrough;
 717
 718	case 0:
 719		mas->cur_xfer_mode = GENI_SE_FIFO;
 720		geni_se_select_mode(se, GENI_SE_FIFO);
 721		ret = 0;
 722		break;
 723	}
 724
 725	/* We always control CS manually */
 726	if (!spi->target) {
 727		spi_tx_cfg = readl(se->base + SE_SPI_TRANS_CFG);
 728		spi_tx_cfg &= ~CS_TOGGLE;
 729		writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG);
 730	}
 731
 732out_pm:
 733	pm_runtime_put(mas->dev);
 734	return ret;
 735}
 736
 737static unsigned int geni_byte_per_fifo_word(struct spi_geni_master *mas)
 738{
 739	/*
 740	 * Calculate how many bytes we'll put in each FIFO word.  If the
 741	 * transfer words don't pack cleanly into a FIFO word we'll just put
 742	 * one transfer word in each FIFO word.  If they do pack we'll pack 'em.
 743	 */
 744	if (mas->fifo_width_bits % mas->cur_bits_per_word)
 745		return roundup_pow_of_two(DIV_ROUND_UP(mas->cur_bits_per_word,
 746						       BITS_PER_BYTE));
 747
 748	return mas->fifo_width_bits / BITS_PER_BYTE;
 749}
 750
 751static bool geni_spi_handle_tx(struct spi_geni_master *mas)
 752{
 753	struct geni_se *se = &mas->se;
 754	unsigned int max_bytes;
 755	const u8 *tx_buf;
 756	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
 757	unsigned int i = 0;
 758
 759	/* Stop the watermark IRQ if nothing to send */
 760	if (!mas->cur_xfer) {
 761		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 762		return false;
 763	}
 764
 765	max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * bytes_per_fifo_word;
 766	if (mas->tx_rem_bytes < max_bytes)
 767		max_bytes = mas->tx_rem_bytes;
 768
 769	tx_buf = mas->cur_xfer->tx_buf + mas->cur_xfer->len - mas->tx_rem_bytes;
 770	while (i < max_bytes) {
 771		unsigned int j;
 772		unsigned int bytes_to_write;
 773		u32 fifo_word = 0;
 774		u8 *fifo_byte = (u8 *)&fifo_word;
 775
 776		bytes_to_write = min(bytes_per_fifo_word, max_bytes - i);
 777		for (j = 0; j < bytes_to_write; j++)
 778			fifo_byte[j] = tx_buf[i++];
 779		iowrite32_rep(se->base + SE_GENI_TX_FIFOn, &fifo_word, 1);
 780	}
 781	mas->tx_rem_bytes -= max_bytes;
 782	if (!mas->tx_rem_bytes) {
 783		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 784		return false;
 785	}
 786	return true;
 787}
 788
 789static void geni_spi_handle_rx(struct spi_geni_master *mas)
 790{
 791	struct geni_se *se = &mas->se;
 792	u32 rx_fifo_status;
 793	unsigned int rx_bytes;
 794	unsigned int rx_last_byte_valid;
 795	u8 *rx_buf;
 796	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
 797	unsigned int i = 0;
 798
 799	rx_fifo_status = readl(se->base + SE_GENI_RX_FIFO_STATUS);
 800	rx_bytes = (rx_fifo_status & RX_FIFO_WC_MSK) * bytes_per_fifo_word;
 801	if (rx_fifo_status & RX_LAST) {
 802		rx_last_byte_valid = rx_fifo_status & RX_LAST_BYTE_VALID_MSK;
 803		rx_last_byte_valid >>= RX_LAST_BYTE_VALID_SHFT;
 804		if (rx_last_byte_valid && rx_last_byte_valid < 4)
 805			rx_bytes -= bytes_per_fifo_word - rx_last_byte_valid;
 806	}
 807
 808	/* Clear out the FIFO and bail if nowhere to put it */
 809	if (!mas->cur_xfer) {
 810		for (i = 0; i < DIV_ROUND_UP(rx_bytes, bytes_per_fifo_word); i++)
 811			readl(se->base + SE_GENI_RX_FIFOn);
 812		return;
 813	}
 814
 815	if (mas->rx_rem_bytes < rx_bytes)
 816		rx_bytes = mas->rx_rem_bytes;
 817
 818	rx_buf = mas->cur_xfer->rx_buf + mas->cur_xfer->len - mas->rx_rem_bytes;
 819	while (i < rx_bytes) {
 820		u32 fifo_word = 0;
 821		u8 *fifo_byte = (u8 *)&fifo_word;
 822		unsigned int bytes_to_read;
 823		unsigned int j;
 824
 825		bytes_to_read = min(bytes_per_fifo_word, rx_bytes - i);
 826		ioread32_rep(se->base + SE_GENI_RX_FIFOn, &fifo_word, 1);
 827		for (j = 0; j < bytes_to_read; j++)
 828			rx_buf[i++] = fifo_byte[j];
 829	}
 830	mas->rx_rem_bytes -= rx_bytes;
 831}
 832
 833static int setup_se_xfer(struct spi_transfer *xfer,
 834				struct spi_geni_master *mas,
 835				u16 mode, struct spi_controller *spi)
 836{
 837	u32 m_cmd = 0;
 838	u32 len;
 839	struct geni_se *se = &mas->se;
 840	int ret;
 841
 842	/*
 843	 * Ensure that our interrupt handler isn't still running from some
 844	 * prior command before we start messing with the hardware behind
 845	 * its back.  We don't need to _keep_ the lock here since we're only
 846	 * worried about racing with out interrupt handler.  The SPI core
 847	 * already handles making sure that we're not trying to do two
 848	 * transfers at once or setting a chip select and doing a transfer
 849	 * concurrently.
 850	 *
 851	 * NOTE: we actually _can't_ hold the lock here because possibly we
 852	 * might call clk_set_rate() which needs to be able to sleep.
 853	 */
 854	spin_lock_irq(&mas->lock);
 855	spin_unlock_irq(&mas->lock);
 856
 857	if (xfer->bits_per_word != mas->cur_bits_per_word) {
 858		spi_setup_word_len(mas, mode, xfer->bits_per_word);
 859		mas->cur_bits_per_word = xfer->bits_per_word;
 860	}
 861
 862	/* Speed and bits per word can be overridden per transfer */
 863	ret = geni_spi_set_clock_and_bw(mas, xfer->speed_hz);
 864	if (ret)
 865		return ret;
 866
 867	mas->tx_rem_bytes = 0;
 868	mas->rx_rem_bytes = 0;
 869
 870	len = get_xfer_len_in_words(xfer, mas);
 
 
 
 
 871
 872	mas->cur_xfer = xfer;
 873	if (xfer->tx_buf) {
 874		m_cmd |= SPI_TX_ONLY;
 875		mas->tx_rem_bytes = xfer->len;
 876		writel(len, se->base + SE_SPI_TX_TRANS_LEN);
 877	}
 878
 879	if (xfer->rx_buf) {
 880		m_cmd |= SPI_RX_ONLY;
 881		writel(len, se->base + SE_SPI_RX_TRANS_LEN);
 882		mas->rx_rem_bytes = xfer->len;
 883	}
 884
 885	/*
 886	 * Select DMA mode if sgt are present; and with only 1 entry
 887	 * This is not a serious limitation because the xfer buffers are
 888	 * expected to fit into in 1 entry almost always, and if any
 889	 * doesn't for any reason we fall back to FIFO mode anyway
 890	 */
 891	if (!xfer->tx_sg.nents && !xfer->rx_sg.nents)
 892		mas->cur_xfer_mode = GENI_SE_FIFO;
 893	else if (xfer->tx_sg.nents > 1 || xfer->rx_sg.nents > 1) {
 894		dev_warn_once(mas->dev, "Doing FIFO, cannot handle tx_nents-%d, rx_nents-%d\n",
 895			xfer->tx_sg.nents, xfer->rx_sg.nents);
 896		mas->cur_xfer_mode = GENI_SE_FIFO;
 897	} else
 898		mas->cur_xfer_mode = GENI_SE_DMA;
 899	geni_se_select_mode(se, mas->cur_xfer_mode);
 900
 901	/*
 902	 * Lock around right before we start the transfer since our
 903	 * interrupt could come in at any time now.
 904	 */
 905	spin_lock_irq(&mas->lock);
 906	geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION);
 907
 908	if (mas->cur_xfer_mode == GENI_SE_DMA) {
 909		if (m_cmd & SPI_RX_ONLY)
 910			geni_se_rx_init_dma(se, sg_dma_address(xfer->rx_sg.sgl),
 911				sg_dma_len(xfer->rx_sg.sgl));
 912		if (m_cmd & SPI_TX_ONLY)
 913			geni_se_tx_init_dma(se, sg_dma_address(xfer->tx_sg.sgl),
 914				sg_dma_len(xfer->tx_sg.sgl));
 915	} else if (m_cmd & SPI_TX_ONLY) {
 916		if (geni_spi_handle_tx(mas))
 917			writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG);
 918	}
 919
 920	spin_unlock_irq(&mas->lock);
 921	return ret;
 922}
 923
 924static int spi_geni_transfer_one(struct spi_controller *spi,
 925				 struct spi_device *slv,
 926				 struct spi_transfer *xfer)
 927{
 928	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 929	int ret;
 930
 931	if (spi_geni_is_abort_still_pending(mas))
 932		return -EBUSY;
 933
 934	/* Terminate and return success for 0 byte length transfer */
 935	if (!xfer->len)
 936		return 0;
 937
 938	if (mas->cur_xfer_mode == GENI_SE_FIFO || mas->cur_xfer_mode == GENI_SE_DMA) {
 939		ret = setup_se_xfer(xfer, mas, slv->mode, spi);
 940		/* SPI framework expects +ve ret code to wait for transfer complete */
 941		if (!ret)
 942			ret = 1;
 943		return ret;
 944	}
 945	return setup_gsi_xfer(xfer, mas, slv, spi);
 946}
 947
 948static irqreturn_t geni_spi_isr(int irq, void *data)
 949{
 950	struct spi_controller *spi = data;
 951	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
 952	struct geni_se *se = &mas->se;
 953	u32 m_irq;
 954
 955	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
 956	if (!m_irq)
 957		return IRQ_NONE;
 958
 959	if (m_irq & (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |
 960		     M_RX_FIFO_RD_ERR_EN | M_RX_FIFO_WR_ERR_EN |
 961		     M_TX_FIFO_RD_ERR_EN | M_TX_FIFO_WR_ERR_EN))
 962		dev_warn(mas->dev, "Unexpected IRQ err status %#010x\n", m_irq);
 963
 964	spin_lock(&mas->lock);
 965
 966	if (mas->cur_xfer_mode == GENI_SE_FIFO) {
 967		if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN))
 968			geni_spi_handle_rx(mas);
 969
 970		if (m_irq & M_TX_FIFO_WATERMARK_EN)
 971			geni_spi_handle_tx(mas);
 972
 973		if (m_irq & M_CMD_DONE_EN) {
 974			if (mas->cur_xfer) {
 975				spi_finalize_current_transfer(spi);
 976				mas->cur_xfer = NULL;
 977				/*
 978				 * If this happens, then a CMD_DONE came before all the
 979				 * Tx buffer bytes were sent out. This is unusual, log
 980				 * this condition and disable the WM interrupt to
 981				 * prevent the system from stalling due an interrupt
 982				 * storm.
 983				 *
 984				 * If this happens when all Rx bytes haven't been
 985				 * received, log the condition. The only known time
 986				 * this can happen is if bits_per_word != 8 and some
 987				 * registers that expect xfer lengths in num spi_words
 988				 * weren't written correctly.
 989				 */
 990				if (mas->tx_rem_bytes) {
 991					writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
 992					dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n",
 993						mas->tx_rem_bytes, mas->cur_bits_per_word);
 994				}
 995				if (mas->rx_rem_bytes)
 996					dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n",
 997						mas->rx_rem_bytes, mas->cur_bits_per_word);
 998			} else {
 999				complete(&mas->cs_done);
1000			}
1001		}
1002	} else if (mas->cur_xfer_mode == GENI_SE_DMA) {
1003		const struct spi_transfer *xfer = mas->cur_xfer;
1004		u32 dma_tx_status = readl_relaxed(se->base + SE_DMA_TX_IRQ_STAT);
1005		u32 dma_rx_status = readl_relaxed(se->base + SE_DMA_RX_IRQ_STAT);
1006
1007		if (dma_tx_status)
1008			writel(dma_tx_status, se->base + SE_DMA_TX_IRQ_CLR);
1009		if (dma_rx_status)
1010			writel(dma_rx_status, se->base + SE_DMA_RX_IRQ_CLR);
1011		if (dma_tx_status & TX_DMA_DONE)
1012			mas->tx_rem_bytes = 0;
1013		if (dma_rx_status & RX_DMA_DONE)
1014			mas->rx_rem_bytes = 0;
1015		if (dma_tx_status & TX_RESET_DONE)
1016			complete(&mas->tx_reset_done);
1017		if (dma_rx_status & RX_RESET_DONE)
1018			complete(&mas->rx_reset_done);
1019		if (!mas->tx_rem_bytes && !mas->rx_rem_bytes && xfer) {
1020			spi_finalize_current_transfer(spi);
1021			mas->cur_xfer = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1022		}
1023	}
1024
1025	if (m_irq & M_CMD_CANCEL_EN)
1026		complete(&mas->cancel_done);
1027	if (m_irq & M_CMD_ABORT_EN)
1028		complete(&mas->abort_done);
1029
1030	/*
1031	 * It's safe or a good idea to Ack all of our interrupts at the end
1032	 * of the function. Specifically:
1033	 * - M_CMD_DONE_EN / M_RX_FIFO_LAST_EN: Edge triggered interrupts and
1034	 *   clearing Acks. Clearing at the end relies on nobody else having
1035	 *   started a new transfer yet or else we could be clearing _their_
1036	 *   done bit, but everyone grabs the spinlock before starting a new
1037	 *   transfer.
1038	 * - M_RX_FIFO_WATERMARK_EN / M_TX_FIFO_WATERMARK_EN: These appear
1039	 *   to be "latched level" interrupts so it's important to clear them
1040	 *   _after_ you've handled the condition and always safe to do so
1041	 *   since they'll re-assert if they're still happening.
1042	 */
1043	writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR);
1044
1045	spin_unlock(&mas->lock);
1046
1047	return IRQ_HANDLED;
1048}
1049
1050static int spi_geni_probe(struct platform_device *pdev)
1051{
1052	int ret, irq;
1053	struct spi_controller *spi;
1054	struct spi_geni_master *mas;
1055	void __iomem *base;
1056	struct clk *clk;
1057	struct device *dev = &pdev->dev;
1058
1059	irq = platform_get_irq(pdev, 0);
1060	if (irq < 0)
1061		return irq;
1062
1063	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
1064	if (ret)
1065		return dev_err_probe(dev, ret, "could not set DMA mask\n");
1066
1067	base = devm_platform_ioremap_resource(pdev, 0);
1068	if (IS_ERR(base))
1069		return PTR_ERR(base);
1070
1071	clk = devm_clk_get(dev, "se");
1072	if (IS_ERR(clk))
1073		return PTR_ERR(clk);
1074
1075	spi = devm_spi_alloc_host(dev, sizeof(*mas));
1076	if (!spi)
1077		return -ENOMEM;
1078
1079	platform_set_drvdata(pdev, spi);
1080	mas = spi_controller_get_devdata(spi);
1081	mas->irq = irq;
1082	mas->dev = dev;
1083	mas->se.dev = dev;
1084	mas->se.wrapper = dev_get_drvdata(dev->parent);
1085	mas->se.base = base;
1086	mas->se.clk = clk;
1087
1088	ret = devm_pm_opp_set_clkname(&pdev->dev, "se");
1089	if (ret)
1090		return ret;
1091	/* OPP table is optional */
1092	ret = devm_pm_opp_of_add_table(&pdev->dev);
1093	if (ret && ret != -ENODEV) {
1094		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
1095		return ret;
1096	}
1097
1098	spi->bus_num = -1;
1099	spi->dev.of_node = dev->of_node;
1100	spi->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_CS_HIGH;
1101	spi->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1102	spi->num_chipselect = 4;
1103	spi->max_speed_hz = 50000000;
1104	spi->max_dma_len = 0xffff0; /* 24 bits for tx/rx dma length */
1105	spi->prepare_message = spi_geni_prepare_message;
1106	spi->transfer_one = spi_geni_transfer_one;
1107	spi->can_dma = geni_can_dma;
1108	spi->dma_map_dev = dev->parent;
1109	spi->auto_runtime_pm = true;
1110	spi->handle_err = spi_geni_handle_err;
1111	spi->use_gpio_descriptors = true;
1112
1113	init_completion(&mas->cs_done);
1114	init_completion(&mas->cancel_done);
1115	init_completion(&mas->abort_done);
1116	init_completion(&mas->tx_reset_done);
1117	init_completion(&mas->rx_reset_done);
1118	spin_lock_init(&mas->lock);
 
 
 
1119
1120	ret = geni_icc_get(&mas->se, NULL);
1121	if (ret)
1122		return ret;
1123
1124	pm_runtime_use_autosuspend(&pdev->dev);
1125	pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
1126	ret = devm_pm_runtime_enable(dev);
1127	if (ret)
1128		return ret;
1129
1130	if (device_property_read_bool(&pdev->dev, "spi-slave"))
1131		spi->target = true;
1132
1133	/* Set the bus quota to a reasonable value for register access */
1134	mas->se.icc_paths[GENI_TO_CORE].avg_bw = Bps_to_icc(CORE_2X_50_MHZ);
1135	mas->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
1136
1137	ret = geni_icc_set_bw(&mas->se);
1138	if (ret)
1139		return ret;
1140
1141	ret = spi_geni_init(mas);
1142	if (ret)
1143		return ret;
1144
1145	/*
1146	 * check the mode supported and set_cs for fifo mode only
1147	 * for dma (gsi) mode, the gsi will set cs based on params passed in
1148	 * TRE
1149	 */
1150	if (!spi->target && mas->cur_xfer_mode == GENI_SE_FIFO)
1151		spi->set_cs = spi_geni_set_cs;
1152
1153	/*
1154	 * TX is required per GSI spec, see setup_gsi_xfer().
1155	 */
1156	if (mas->cur_xfer_mode == GENI_GPI_DMA)
1157		spi->flags = SPI_CONTROLLER_MUST_TX;
1158
1159	ret = devm_request_irq(dev, mas->irq, geni_spi_isr, 0, dev_name(dev), spi);
1160	if (ret)
1161		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1162
1163	return devm_spi_register_controller(dev, spi);
 
 
1164}
1165
1166static int __maybe_unused spi_geni_runtime_suspend(struct device *dev)
1167{
1168	struct spi_controller *spi = dev_get_drvdata(dev);
1169	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
1170	int ret;
1171
1172	/* Drop the performance state vote */
1173	dev_pm_opp_set_rate(dev, 0);
1174
1175	ret = geni_se_resources_off(&mas->se);
1176	if (ret)
1177		return ret;
1178
1179	return geni_icc_disable(&mas->se);
1180}
1181
1182static int __maybe_unused spi_geni_runtime_resume(struct device *dev)
1183{
1184	struct spi_controller *spi = dev_get_drvdata(dev);
1185	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
1186	int ret;
1187
1188	ret = geni_icc_enable(&mas->se);
1189	if (ret)
1190		return ret;
1191
1192	ret = geni_se_resources_on(&mas->se);
1193	if (ret)
1194		return ret;
1195
1196	return dev_pm_opp_set_rate(mas->dev, mas->cur_sclk_hz);
1197}
1198
1199static int __maybe_unused spi_geni_suspend(struct device *dev)
1200{
1201	struct spi_controller *spi = dev_get_drvdata(dev);
1202	int ret;
1203
1204	ret = spi_controller_suspend(spi);
1205	if (ret)
1206		return ret;
1207
1208	ret = pm_runtime_force_suspend(dev);
1209	if (ret)
1210		spi_controller_resume(spi);
1211
1212	return ret;
1213}
1214
1215static int __maybe_unused spi_geni_resume(struct device *dev)
1216{
1217	struct spi_controller *spi = dev_get_drvdata(dev);
1218	int ret;
1219
1220	ret = pm_runtime_force_resume(dev);
1221	if (ret)
1222		return ret;
1223
1224	ret = spi_controller_resume(spi);
1225	if (ret)
1226		pm_runtime_force_suspend(dev);
1227
1228	return ret;
1229}
1230
1231static const struct dev_pm_ops spi_geni_pm_ops = {
1232	SET_RUNTIME_PM_OPS(spi_geni_runtime_suspend,
1233					spi_geni_runtime_resume, NULL)
1234	SET_SYSTEM_SLEEP_PM_OPS(spi_geni_suspend, spi_geni_resume)
1235};
1236
1237static const struct of_device_id spi_geni_dt_match[] = {
1238	{ .compatible = "qcom,geni-spi" },
1239	{}
1240};
1241MODULE_DEVICE_TABLE(of, spi_geni_dt_match);
1242
1243static struct platform_driver spi_geni_driver = {
1244	.probe  = spi_geni_probe,
 
1245	.driver = {
1246		.name = "geni_spi",
1247		.pm = &spi_geni_pm_ops,
1248		.of_match_table = spi_geni_dt_match,
1249	},
1250};
1251module_platform_driver(spi_geni_driver);
1252
1253MODULE_DESCRIPTION("SPI driver for GENI based QUP cores");
1254MODULE_LICENSE("GPL v2");