brintos

brintos / linux-shallow public Read only

0
0
Text · 33.2 KiB · 768d748 Raw
1255 lines · c
1// SPDX-License-Identifier: GPL-2.02// 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		0x22422#define CPHA			BIT(0)23 24#define SE_SPI_LOOPBACK		0x22c25#define LOOPBACK_ENABLE		0x126#define NORMAL_MODE		0x027#define LOOPBACK_MSK		GENMASK(1, 0)28 29#define SE_SPI_CPOL		0x23030#define CPOL			BIT(2)31 32#define SE_SPI_DEMUX_OUTPUT_INV	0x24c33#define CS_DEMUX_OUTPUT_INV_MSK	GENMASK(3, 0)34 35#define SE_SPI_DEMUX_SEL	0x25036#define CS_DEMUX_OUTPUT_SEL	GENMASK(3, 0)37 38#define SE_SPI_TRANS_CFG	0x25c39#define CS_TOGGLE		BIT(1)40 41#define SE_SPI_WORD_LEN		0x26842#define WORD_LEN_MSK		GENMASK(9, 0)43#define MIN_WORD_LEN		444 45#define SE_SPI_TX_TRANS_LEN	0x26c46#define SE_SPI_RX_TRANS_LEN	0x27047#define TRANS_LEN_MSK		GENMASK(23, 0)48 49#define SE_SPI_PRE_POST_CMD_DLY	0x27450 51#define SE_SPI_DELAY_COUNTERS	0x27852#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		1055 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		161#define SPI_RX_ONLY		262#define SPI_TX_RX		763#define SPI_CS_ASSERT		864#define SPI_CS_DEASSERT		965#define SPI_SCK_ONLY		1066/* 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	else143		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 target166		 * doesn`t support CMD Cancel sequnece167		 */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 never191		 * 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 wait220			 * for lock in this function because isr was holding the lock221			 * 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 cancel263	 * times out then an abort times out is if something is blocking our264	 * interrupt handler from running.  Avoid starting any new transfers265	 * 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 more280	 * 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	else323		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 be346	 * 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	else351		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 frequency376	 * or the frequency closer to the requested frequency.377	 * For that reason requested frequency is stored in the378	 * cur_speed_hz and referred in the consecutive transfer instead379	 * 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 void435spi_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 would522	 * need TX to be prepared per GSI spec523	 */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	else554		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	else579		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 configure685	 * 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	else697		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 the713		 * FIFO mode, so fallthrough714		 */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 the741	 * transfer words don't pack cleanly into a FIFO word we'll just put742	 * 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 some844	 * prior command before we start messing with the hardware behind845	 * its back.  We don't need to _keep_ the lock here since we're only846	 * worried about racing with out interrupt handler.  The SPI core847	 * already handles making sure that we're not trying to do two848	 * transfers at once or setting a chip select and doing a transfer849	 * concurrently.850	 *851	 * NOTE: we actually _can't_ hold the lock here because possibly we852	 * 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 entry887	 * This is not a serious limitation because the xfer buffers are888	 * expected to fit into in 1 entry almost always, and if any889	 * doesn't for any reason we fall back to FIFO mode anyway890	 */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	} else898		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 our903	 * 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 the979				 * Tx buffer bytes were sent out. This is unusual, log980				 * this condition and disable the WM interrupt to981				 * prevent the system from stalling due an interrupt982				 * storm.983				 *984				 * If this happens when all Rx bytes haven't been985				 * received, log the condition. The only known time986				 * this can happen is if bits_per_word != 8 and some987				 * registers that expect xfer lengths in num spi_words988				 * 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 end1032	 * of the function. Specifically:1033	 * - M_CMD_DONE_EN / M_RX_FIFO_LAST_EN: Edge triggered interrupts and1034	 *   clearing Acks. Clearing at the end relies on nobody else having1035	 *   started a new transfer yet or else we could be clearing _their_1036	 *   done bit, but everyone grabs the spinlock before starting a new1037	 *   transfer.1038	 * - M_RX_FIFO_WATERMARK_EN / M_TX_FIFO_WATERMARK_EN: These appear1039	 *   to be "latched level" interrupts so it's important to clear them1040	 *   _after_ you've handled the condition and always safe to do so1041	 *   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 only1147	 * for dma (gsi) mode, the gsi will set cs based on params passed in1148	 * TRE1149	 */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");1255