[linux.git] / drivers / spi / spi-qcom-qspi.c

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2017-2018, The Linux foundation. All rights reserved.

#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pm_runtime.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-mem.h>


#define QSPI_NUM_CS		2
#define QSPI_BYTES_PER_WORD	4

#define MSTR_CONFIG		0x0000
#define FULL_CYCLE_MODE		BIT(3)
#define FB_CLK_EN		BIT(4)
#define PIN_HOLDN		BIT(6)
#define PIN_WPN			BIT(7)
#define DMA_ENABLE		BIT(8)
#define BIG_ENDIAN_MODE		BIT(9)
#define SPI_MODE_MSK		0xc00
#define SPI_MODE_SHFT		10
#define CHIP_SELECT_NUM		BIT(12)
#define SBL_EN			BIT(13)
#define LPA_BASE_MSK		0x3c000
#define LPA_BASE_SHFT		14
#define TX_DATA_DELAY_MSK	0xc0000
#define TX_DATA_DELAY_SHFT	18
#define TX_CLK_DELAY_MSK	0x300000
#define TX_CLK_DELAY_SHFT	20
#define TX_CS_N_DELAY_MSK	0xc00000
#define TX_CS_N_DELAY_SHFT	22
#define TX_DATA_OE_DELAY_MSK	0x3000000
#define TX_DATA_OE_DELAY_SHFT	24

#define AHB_MASTER_CFG				0x0004
#define HMEM_TYPE_START_MID_TRANS_MSK		0x7
#define HMEM_TYPE_START_MID_TRANS_SHFT		0
#define HMEM_TYPE_LAST_TRANS_MSK		0x38
#define HMEM_TYPE_LAST_TRANS_SHFT		3
#define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_MSK	0xc0
#define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_SHFT	6
#define HMEMTYPE_READ_TRANS_MSK			0x700
#define HMEMTYPE_READ_TRANS_SHFT		8
#define HSHARED					BIT(11)
#define HINNERSHARED				BIT(12)

#define MSTR_INT_EN		0x000C
#define MSTR_INT_STATUS		0x0010
#define RESP_FIFO_UNDERRUN	BIT(0)
#define RESP_FIFO_NOT_EMPTY	BIT(1)
#define RESP_FIFO_RDY		BIT(2)
#define HRESP_FROM_NOC_ERR	BIT(3)
#define WR_FIFO_EMPTY		BIT(9)
#define WR_FIFO_FULL		BIT(10)
#define WR_FIFO_OVERRUN		BIT(11)
#define TRANSACTION_DONE	BIT(16)
#define QSPI_ERR_IRQS		(RESP_FIFO_UNDERRUN | HRESP_FROM_NOC_ERR | \
				 WR_FIFO_OVERRUN)
#define QSPI_ALL_IRQS		(QSPI_ERR_IRQS | RESP_FIFO_RDY | \
				 WR_FIFO_EMPTY | WR_FIFO_FULL | \
				 TRANSACTION_DONE)

#define PIO_XFER_CTRL		0x0014
#define REQUEST_COUNT_MSK	0xffff

#define PIO_XFER_CFG		0x0018
#define TRANSFER_DIRECTION	BIT(0)
#define MULTI_IO_MODE_MSK	0xe
#define MULTI_IO_MODE_SHFT	1
#define TRANSFER_FRAGMENT	BIT(8)
#define SDR_1BIT		1
#define SDR_2BIT		2
#define SDR_4BIT		3
#define DDR_1BIT		5
#define DDR_2BIT		6
#define DDR_4BIT		7
#define DMA_DESC_SINGLE_SPI	1
#define DMA_DESC_DUAL_SPI	2
#define DMA_DESC_QUAD_SPI	3

#define PIO_XFER_STATUS		0x001c
#define WR_FIFO_BYTES_MSK	0xffff0000
#define WR_FIFO_BYTES_SHFT	16

#define PIO_DATAOUT_1B		0x0020
#define PIO_DATAOUT_4B		0x0024

#define RD_FIFO_CFG		0x0028
#define CONTINUOUS_MODE		BIT(0)

#define RD_FIFO_STATUS	0x002c
#define FIFO_EMPTY	BIT(11)
#define WR_CNTS_MSK	0x7f0
#define WR_CNTS_SHFT	4
#define RDY_64BYTE	BIT(3)
#define RDY_32BYTE	BIT(2)
#define RDY_16BYTE	BIT(1)
#define FIFO_RDY	BIT(0)

#define RD_FIFO_RESET		0x0030
#define RESET_FIFO		BIT(0)

#define CUR_MEM_ADDR		0x0048
#define HW_VERSION		0x004c
#define RD_FIFO			0x0050
#define SAMPLING_CLK_CFG	0x0090
#define SAMPLING_CLK_STATUS	0x0094


enum qspi_dir {
	QSPI_READ,
	QSPI_WRITE,
};

struct qspi_xfer {
	union {
		const void *tx_buf;
		void *rx_buf;
	};
	unsigned int rem_bytes;
	unsigned int buswidth;
	enum qspi_dir dir;
	bool is_last;
};

enum qspi_clocks {
	QSPI_CLK_CORE,
	QSPI_CLK_IFACE,
	QSPI_NUM_CLKS
};

struct qcom_qspi {
	void __iomem *base;
	struct device *dev;
	struct clk_bulk_data clks[QSPI_NUM_CLKS];
	struct qspi_xfer xfer;
	/* Lock to protect xfer and IRQ accessed registers */
	spinlock_t lock;
};

static u32 qspi_buswidth_to_iomode(struct qcom_qspi *ctrl,
				   unsigned int buswidth)
{
	switch (buswidth) {
	case 1:
		return SDR_1BIT << MULTI_IO_MODE_SHFT;
	case 2:
		return SDR_2BIT << MULTI_IO_MODE_SHFT;
	case 4:
		return SDR_4BIT << MULTI_IO_MODE_SHFT;
	default:
		dev_warn_once(ctrl->dev,
				"Unexpected bus width: %u\n", buswidth);
		return SDR_1BIT << MULTI_IO_MODE_SHFT;
	}
}

static void qcom_qspi_pio_xfer_cfg(struct qcom_qspi *ctrl)
{
	u32 pio_xfer_cfg;
	const struct qspi_xfer *xfer;

	xfer = &ctrl->xfer;
	pio_xfer_cfg = readl(ctrl->base + PIO_XFER_CFG);
	pio_xfer_cfg &= ~TRANSFER_DIRECTION;
	pio_xfer_cfg |= xfer->dir;
	if (xfer->is_last)
		pio_xfer_cfg &= ~TRANSFER_FRAGMENT;
	else
		pio_xfer_cfg |= TRANSFER_FRAGMENT;
	pio_xfer_cfg &= ~MULTI_IO_MODE_MSK;
	pio_xfer_cfg |= qspi_buswidth_to_iomode(ctrl, xfer->buswidth);

	writel(pio_xfer_cfg, ctrl->base + PIO_XFER_CFG);
}

static void qcom_qspi_pio_xfer_ctrl(struct qcom_qspi *ctrl)
{
	u32 pio_xfer_ctrl;

	pio_xfer_ctrl = readl(ctrl->base + PIO_XFER_CTRL);
	pio_xfer_ctrl &= ~REQUEST_COUNT_MSK;
	pio_xfer_ctrl |= ctrl->xfer.rem_bytes;
	writel(pio_xfer_ctrl, ctrl->base + PIO_XFER_CTRL);
}

static void qcom_qspi_pio_xfer(struct qcom_qspi *ctrl)
{
	u32 ints;

	qcom_qspi_pio_xfer_cfg(ctrl);

	/* Ack any previous interrupts that might be hanging around */
	writel(QSPI_ALL_IRQS, ctrl->base + MSTR_INT_STATUS);

	/* Setup new interrupts */
	if (ctrl->xfer.dir == QSPI_WRITE)
		ints = QSPI_ERR_IRQS | WR_FIFO_EMPTY;
	else
		ints = QSPI_ERR_IRQS | RESP_FIFO_RDY;
	writel(ints, ctrl->base + MSTR_INT_EN);

	/* Kick off the transfer */
	qcom_qspi_pio_xfer_ctrl(ctrl);
}

static void qcom_qspi_handle_err(struct spi_master *master,
				 struct spi_message *msg)
{
	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
	unsigned long flags;

	spin_lock_irqsave(&ctrl->lock, flags);
	writel(0, ctrl->base + MSTR_INT_EN);
	ctrl->xfer.rem_bytes = 0;
	spin_unlock_irqrestore(&ctrl->lock, flags);
}

static int qcom_qspi_transfer_one(struct spi_master *master,
				  struct spi_device *slv,
				  struct spi_transfer *xfer)
{
	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
	int ret;
	unsigned long speed_hz;
	unsigned long flags;

	speed_hz = slv->max_speed_hz;
	if (xfer->speed_hz)
		speed_hz = xfer->speed_hz;

	/* In regular operation (SBL_EN=1) core must be 4x transfer clock */
	ret = clk_set_rate(ctrl->clks[QSPI_CLK_CORE].clk, speed_hz * 4);
	if (ret) {
		dev_err(ctrl->dev, "Failed to set core clk %d\n", ret);
		return ret;
	}

	spin_lock_irqsave(&ctrl->lock, flags);

	/* We are half duplex, so either rx or tx will be set */
	if (xfer->rx_buf) {
		ctrl->xfer.dir = QSPI_READ;
		ctrl->xfer.buswidth = xfer->rx_nbits;
		ctrl->xfer.rx_buf = xfer->rx_buf;
	} else {
		ctrl->xfer.dir = QSPI_WRITE;
		ctrl->xfer.buswidth = xfer->tx_nbits;
		ctrl->xfer.tx_buf = xfer->tx_buf;
	}
	ctrl->xfer.is_last = list_is_last(&xfer->transfer_list,
					  &master->cur_msg->transfers);
	ctrl->xfer.rem_bytes = xfer->len;
	qcom_qspi_pio_xfer(ctrl);

	spin_unlock_irqrestore(&ctrl->lock, flags);

	/* We'll call spi_finalize_current_transfer() when done */
	return 1;
}

static int qcom_qspi_prepare_message(struct spi_master *master,
				     struct spi_message *message)
{
	u32 mstr_cfg;
	struct qcom_qspi *ctrl;
	int tx_data_oe_delay = 1;
	int tx_data_delay = 1;
	unsigned long flags;

	ctrl = spi_master_get_devdata(master);
	spin_lock_irqsave(&ctrl->lock, flags);

	mstr_cfg = readl(ctrl->base + MSTR_CONFIG);
	mstr_cfg &= ~CHIP_SELECT_NUM;
	if (message->spi->chip_select)
		mstr_cfg |= CHIP_SELECT_NUM;

	mstr_cfg |= FB_CLK_EN | PIN_WPN | PIN_HOLDN | SBL_EN | FULL_CYCLE_MODE;
	mstr_cfg &= ~(SPI_MODE_MSK | TX_DATA_OE_DELAY_MSK | TX_DATA_DELAY_MSK);
	mstr_cfg |= message->spi->mode << SPI_MODE_SHFT;
	mstr_cfg |= tx_data_oe_delay << TX_DATA_OE_DELAY_SHFT;
	mstr_cfg |= tx_data_delay << TX_DATA_DELAY_SHFT;
	mstr_cfg &= ~DMA_ENABLE;

	writel(mstr_cfg, ctrl->base + MSTR_CONFIG);
	spin_unlock_irqrestore(&ctrl->lock, flags);

	return 0;
}

static irqreturn_t pio_read(struct qcom_qspi *ctrl)
{
	u32 rd_fifo_status;
	u32 rd_fifo;
	unsigned int wr_cnts;
	unsigned int bytes_to_read;
	unsigned int words_to_read;
	u32 *word_buf;
	u8 *byte_buf;
	int i;

	rd_fifo_status = readl(ctrl->base + RD_FIFO_STATUS);

	if (!(rd_fifo_status & FIFO_RDY)) {
		dev_dbg(ctrl->dev, "Spurious IRQ %#x\n", rd_fifo_status);
		return IRQ_NONE;
	}

	wr_cnts = (rd_fifo_status & WR_CNTS_MSK) >> WR_CNTS_SHFT;
	wr_cnts = min(wr_cnts, ctrl->xfer.rem_bytes);

	words_to_read = wr_cnts / QSPI_BYTES_PER_WORD;
	bytes_to_read = wr_cnts % QSPI_BYTES_PER_WORD;

	if (words_to_read) {
		word_buf = ctrl->xfer.rx_buf;
		ctrl->xfer.rem_bytes -= words_to_read * QSPI_BYTES_PER_WORD;
		ioread32_rep(ctrl->base + RD_FIFO, word_buf, words_to_read);
		ctrl->xfer.rx_buf = word_buf + words_to_read;
	}

	if (bytes_to_read) {
		byte_buf = ctrl->xfer.rx_buf;
		rd_fifo = readl(ctrl->base + RD_FIFO);
		ctrl->xfer.rem_bytes -= bytes_to_read;
		for (i = 0; i < bytes_to_read; i++)
			*byte_buf++ = rd_fifo >> (i * BITS_PER_BYTE);
		ctrl->xfer.rx_buf = byte_buf;
	}

	return IRQ_HANDLED;
}

static irqreturn_t pio_write(struct qcom_qspi *ctrl)
{
	const void *xfer_buf = ctrl->xfer.tx_buf;
	const int *word_buf;
	const char *byte_buf;
	unsigned int wr_fifo_bytes;
	unsigned int wr_fifo_words;
	unsigned int wr_size;
	unsigned int rem_words;

	wr_fifo_bytes = readl(ctrl->base + PIO_XFER_STATUS);
	wr_fifo_bytes >>= WR_FIFO_BYTES_SHFT;

	if (ctrl->xfer.rem_bytes < QSPI_BYTES_PER_WORD) {
		/* Process the last 1-3 bytes */
		wr_size = min(wr_fifo_bytes, ctrl->xfer.rem_bytes);
		ctrl->xfer.rem_bytes -= wr_size;

		byte_buf = xfer_buf;
		while (wr_size--)
			writel(*byte_buf++,
			       ctrl->base + PIO_DATAOUT_1B);
		ctrl->xfer.tx_buf = byte_buf;
	} else {
		/*
		 * Process all the whole words; to keep things simple we'll
		 * just wait for the next interrupt to handle the last 1-3
		 * bytes if we don't have an even number of words.
		 */
		rem_words = ctrl->xfer.rem_bytes / QSPI_BYTES_PER_WORD;
		wr_fifo_words = wr_fifo_bytes / QSPI_BYTES_PER_WORD;

		wr_size = min(rem_words, wr_fifo_words);
		ctrl->xfer.rem_bytes -= wr_size * QSPI_BYTES_PER_WORD;

		word_buf = xfer_buf;
		iowrite32_rep(ctrl->base + PIO_DATAOUT_4B, word_buf, wr_size);
		ctrl->xfer.tx_buf = word_buf + wr_size;

	}

	return IRQ_HANDLED;
}

static irqreturn_t qcom_qspi_irq(int irq, void *dev_id)
{
	u32 int_status;
	struct qcom_qspi *ctrl = dev_id;
	irqreturn_t ret = IRQ_NONE;
	unsigned long flags;

	spin_lock_irqsave(&ctrl->lock, flags);

	int_status = readl(ctrl->base + MSTR_INT_STATUS);
	writel(int_status, ctrl->base + MSTR_INT_STATUS);

	if (ctrl->xfer.dir == QSPI_WRITE) {
		if (int_status & WR_FIFO_EMPTY)
			ret = pio_write(ctrl);
	} else {
		if (int_status & RESP_FIFO_RDY)
			ret = pio_read(ctrl);
	}

	if (int_status & QSPI_ERR_IRQS) {
		if (int_status & RESP_FIFO_UNDERRUN)
			dev_err(ctrl->dev, "IRQ error: FIFO underrun\n");
		if (int_status & WR_FIFO_OVERRUN)
			dev_err(ctrl->dev, "IRQ error: FIFO overrun\n");
		if (int_status & HRESP_FROM_NOC_ERR)
			dev_err(ctrl->dev, "IRQ error: NOC response error\n");
		ret = IRQ_HANDLED;
	}

	if (!ctrl->xfer.rem_bytes) {
		writel(0, ctrl->base + MSTR_INT_EN);
		spi_finalize_current_transfer(dev_get_drvdata(ctrl->dev));
	}

	spin_unlock_irqrestore(&ctrl->lock, flags);
	return ret;
}

static int qcom_qspi_probe(struct platform_device *pdev)
{
	int ret;
	struct device *dev;
	struct spi_master *master;
	struct qcom_qspi *ctrl;

	dev = &pdev->dev;

	master = spi_alloc_master(dev, sizeof(*ctrl));
	if (!master)
		return -ENOMEM;

	platform_set_drvdata(pdev, master);

	ctrl = spi_master_get_devdata(master);

	spin_lock_init(&ctrl->lock);
	ctrl->dev = dev;
	ctrl->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(ctrl->base)) {
		ret = PTR_ERR(ctrl->base);
		goto exit_probe_master_put;
	}

	ctrl->clks[QSPI_CLK_CORE].id = "core";
	ctrl->clks[QSPI_CLK_IFACE].id = "iface";
	ret = devm_clk_bulk_get(dev, QSPI_NUM_CLKS, ctrl->clks);
	if (ret)
		goto exit_probe_master_put;

	ret = platform_get_irq(pdev, 0);
	if (ret < 0)
		goto exit_probe_master_put;
	ret = devm_request_irq(dev, ret, qcom_qspi_irq,
			IRQF_TRIGGER_HIGH, dev_name(dev), ctrl);
	if (ret) {
		dev_err(dev, "Failed to request irq %d\n", ret);
		goto exit_probe_master_put;
	}

	master->max_speed_hz = 300000000;
	master->num_chipselect = QSPI_NUM_CS;
	master->bus_num = -1;
	master->dev.of_node = pdev->dev.of_node;
	master->mode_bits = SPI_MODE_0 |
			    SPI_TX_DUAL | SPI_RX_DUAL |
			    SPI_TX_QUAD | SPI_RX_QUAD;
	master->flags = SPI_MASTER_HALF_DUPLEX;
	master->prepare_message = qcom_qspi_prepare_message;
	master->transfer_one = qcom_qspi_transfer_one;
	master->handle_err = qcom_qspi_handle_err;
	master->auto_runtime_pm = true;

	pm_runtime_enable(dev);

	ret = spi_register_master(master);
	if (!ret)
		return 0;

	pm_runtime_disable(dev);

exit_probe_master_put:
	spi_master_put(master);

	return ret;
}

static int qcom_qspi_remove(struct platform_device *pdev)
{
	struct spi_master *master = platform_get_drvdata(pdev);

	/* Unregister _before_ disabling pm_runtime() so we stop transfers */
	spi_unregister_master(master);

	pm_runtime_disable(&pdev->dev);

	return 0;
}

static int __maybe_unused qcom_qspi_runtime_suspend(struct device *dev)
{
	struct spi_master *master = dev_get_drvdata(dev);
	struct qcom_qspi *ctrl = spi_master_get_devdata(master);

	clk_bulk_disable_unprepare(QSPI_NUM_CLKS, ctrl->clks);

	return 0;
}

static int __maybe_unused qcom_qspi_runtime_resume(struct device *dev)
{
	struct spi_master *master = dev_get_drvdata(dev);
	struct qcom_qspi *ctrl = spi_master_get_devdata(master);

	return clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks);
}

static int __maybe_unused qcom_qspi_suspend(struct device *dev)
{
	struct spi_master *master = dev_get_drvdata(dev);
	int ret;

	ret = spi_master_suspend(master);
	if (ret)
		return ret;

	ret = pm_runtime_force_suspend(dev);
	if (ret)
		spi_master_resume(master);

	return ret;
}

static int __maybe_unused qcom_qspi_resume(struct device *dev)
{
	struct spi_master *master = dev_get_drvdata(dev);
	int ret;

	ret = pm_runtime_force_resume(dev);
	if (ret)
		return ret;

	ret = spi_master_resume(master);
	if (ret)
		pm_runtime_force_suspend(dev);

	return ret;
}

static const struct dev_pm_ops qcom_qspi_dev_pm_ops = {
	SET_RUNTIME_PM_OPS(qcom_qspi_runtime_suspend,
			   qcom_qspi_runtime_resume, NULL)
	SET_SYSTEM_SLEEP_PM_OPS(qcom_qspi_suspend, qcom_qspi_resume)
};

static const struct of_device_id qcom_qspi_dt_match[] = {
	{ .compatible = "qcom,qspi-v1", },
	{ }
};
MODULE_DEVICE_TABLE(of, qcom_qspi_dt_match);

static struct platform_driver qcom_qspi_driver = {
	.driver = {
		.name		= "qcom_qspi",
		.pm		= &qcom_qspi_dev_pm_ops,
		.of_match_table = qcom_qspi_dt_match,
	},
	.probe = qcom_qspi_probe,
	.remove = qcom_qspi_remove,
};
module_platform_driver(qcom_qspi_driver);

MODULE_DESCRIPTION("SPI driver for QSPI cores");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
04000dc6 GM	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/interrupt.h>
	6	#include <linux/io.h>
	7	#include <linux/module.h>
	8	#include <linux/of.h>
	9	#include <linux/of_platform.h>
	10	#include <linux/pm_runtime.h>
	11	#include <linux/spi/spi.h>
	12	#include <linux/spi/spi-mem.h>
	13
	14
	15	#define QSPI_NUM_CS 2
	16	#define QSPI_BYTES_PER_WORD 4
	17
	18	#define MSTR_CONFIG 0x0000
	19	#define FULL_CYCLE_MODE BIT(3)
	20	#define FB_CLK_EN BIT(4)
	21	#define PIN_HOLDN BIT(6)
	22	#define PIN_WPN BIT(7)
	23	#define DMA_ENABLE BIT(8)
	24	#define BIG_ENDIAN_MODE BIT(9)
	25	#define SPI_MODE_MSK 0xc00
	26	#define SPI_MODE_SHFT 10
	27	#define CHIP_SELECT_NUM BIT(12)
	28	#define SBL_EN BIT(13)
	29	#define LPA_BASE_MSK 0x3c000
	30	#define LPA_BASE_SHFT 14
	31	#define TX_DATA_DELAY_MSK 0xc0000
	32	#define TX_DATA_DELAY_SHFT 18
	33	#define TX_CLK_DELAY_MSK 0x300000
	34	#define TX_CLK_DELAY_SHFT 20
	35	#define TX_CS_N_DELAY_MSK 0xc00000
	36	#define TX_CS_N_DELAY_SHFT 22
	37	#define TX_DATA_OE_DELAY_MSK 0x3000000
	38	#define TX_DATA_OE_DELAY_SHFT 24
	39
	40	#define AHB_MASTER_CFG 0x0004
	41	#define HMEM_TYPE_START_MID_TRANS_MSK 0x7
	42	#define HMEM_TYPE_START_MID_TRANS_SHFT 0
	43	#define HMEM_TYPE_LAST_TRANS_MSK 0x38
	44	#define HMEM_TYPE_LAST_TRANS_SHFT 3
	45	#define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_MSK 0xc0
	46	#define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_SHFT 6
	47	#define HMEMTYPE_READ_TRANS_MSK 0x700
	48	#define HMEMTYPE_READ_TRANS_SHFT 8
	49	#define HSHARED BIT(11)
	50	#define HINNERSHARED BIT(12)
	51
	52	#define MSTR_INT_EN 0x000C
	53	#define MSTR_INT_STATUS 0x0010
	54	#define RESP_FIFO_UNDERRUN BIT(0)
	55	#define RESP_FIFO_NOT_EMPTY BIT(1)
	56	#define RESP_FIFO_RDY BIT(2)
	57	#define HRESP_FROM_NOC_ERR BIT(3)
	58	#define WR_FIFO_EMPTY BIT(9)
	59	#define WR_FIFO_FULL BIT(10)
	60	#define WR_FIFO_OVERRUN BIT(11)
	61	#define TRANSACTION_DONE BIT(16)
	62	#define QSPI_ERR_IRQS (RESP_FIFO_UNDERRUN \| HRESP_FROM_NOC_ERR \| \
	63	WR_FIFO_OVERRUN)
	64	#define QSPI_ALL_IRQS (QSPI_ERR_IRQS \| RESP_FIFO_RDY \| \
65	WR_FIFO_EMPTY \| WR_FIFO_FULL \| \
66	TRANSACTION_DONE)
67
68	#define PIO_XFER_CTRL 0x0014
69	#define REQUEST_COUNT_MSK 0xffff
70
71	#define PIO_XFER_CFG 0x0018
72	#define TRANSFER_DIRECTION BIT(0)
73	#define MULTI_IO_MODE_MSK 0xe
74	#define MULTI_IO_MODE_SHFT 1
75	#define TRANSFER_FRAGMENT BIT(8)
76	#define SDR_1BIT 1
77	#define SDR_2BIT 2
78	#define SDR_4BIT 3
79	#define DDR_1BIT 5
80	#define DDR_2BIT 6
81	#define DDR_4BIT 7
82	#define DMA_DESC_SINGLE_SPI 1
83	#define DMA_DESC_DUAL_SPI 2
84	#define DMA_DESC_QUAD_SPI 3
85
86	#define PIO_XFER_STATUS 0x001c
87	#define WR_FIFO_BYTES_MSK 0xffff0000
88	#define WR_FIFO_BYTES_SHFT 16
89
90	#define PIO_DATAOUT_1B 0x0020
91	#define PIO_DATAOUT_4B 0x0024
92
478652f3 RC	93	#define RD_FIFO_CFG 0x0028
	94	#define CONTINUOUS_MODE BIT(0)
	95
04000dc6 GM	96	#define RD_FIFO_STATUS 0x002c
	97	#define FIFO_EMPTY BIT(11)
	98	#define WR_CNTS_MSK 0x7f0
	99	#define WR_CNTS_SHFT 4
	100	#define RDY_64BYTE BIT(3)
	101	#define RDY_32BYTE BIT(2)
	102	#define RDY_16BYTE BIT(1)
	103	#define FIFO_RDY BIT(0)
	104
04000dc6 GM	105	#define RD_FIFO_RESET 0x0030
	106	#define RESET_FIFO BIT(0)
	107
	108	#define CUR_MEM_ADDR 0x0048
	109	#define HW_VERSION 0x004c
	110	#define RD_FIFO 0x0050
	111	#define SAMPLING_CLK_CFG 0x0090
	112	#define SAMPLING_CLK_STATUS 0x0094
	113
	114
	115	enum qspi_dir {
	116	QSPI_READ,
	117	QSPI_WRITE,
	118	};
	119
	120	struct qspi_xfer {
	121	union {
	122	const void *tx_buf;
	123	void *rx_buf;
	124	};
	125	unsigned int rem_bytes;
	126	unsigned int buswidth;
	127	enum qspi_dir dir;
	128	bool is_last;
	129	};
	130
	131	enum qspi_clocks {
	132	QSPI_CLK_CORE,
	133	QSPI_CLK_IFACE,
	134	QSPI_NUM_CLKS
	135	};
	136
	137	struct qcom_qspi {
	138	void __iomem *base;
	139	struct device *dev;
	140	struct clk_bulk_data clks[QSPI_NUM_CLKS];
	141	struct qspi_xfer xfer;
478652f3	142	/* Lock to protect xfer and IRQ accessed registers */
04000dc6 GM	143	spinlock_t lock;
	144	};
	145
	146	static u32 qspi_buswidth_to_iomode(struct qcom_qspi *ctrl,
	147	unsigned int buswidth)
	148	{
	149	switch (buswidth) {
	150	case 1:
	151	return SDR_1BIT << MULTI_IO_MODE_SHFT;
	152	case 2:
	153	return SDR_2BIT << MULTI_IO_MODE_SHFT;
	154	case 4:
	155	return SDR_4BIT << MULTI_IO_MODE_SHFT;
	156	default:
	157	dev_warn_once(ctrl->dev,
	158	"Unexpected bus width: %u\n", buswidth);
	159	return SDR_1BIT << MULTI_IO_MODE_SHFT;
	160	}
	161	}
	162
	163	static void qcom_qspi_pio_xfer_cfg(struct qcom_qspi *ctrl)
	164	{
	165	u32 pio_xfer_cfg;
	166	const struct qspi_xfer *xfer;
	167
	168	xfer = &ctrl->xfer;
	169	pio_xfer_cfg = readl(ctrl->base + PIO_XFER_CFG);
	170	pio_xfer_cfg &= ~TRANSFER_DIRECTION;
	171	pio_xfer_cfg \|= xfer->dir;
	172	if (xfer->is_last)
	173	pio_xfer_cfg &= ~TRANSFER_FRAGMENT;
	174	else
	175	pio_xfer_cfg \|= TRANSFER_FRAGMENT;
	176	pio_xfer_cfg &= ~MULTI_IO_MODE_MSK;
	177	pio_xfer_cfg \|= qspi_buswidth_to_iomode(ctrl, xfer->buswidth);
	178
	179	writel(pio_xfer_cfg, ctrl->base + PIO_XFER_CFG);
	180	}
	181
	182	static void qcom_qspi_pio_xfer_ctrl(struct qcom_qspi *ctrl)
	183	{
	184	u32 pio_xfer_ctrl;
	185
	186	pio_xfer_ctrl = readl(ctrl->base + PIO_XFER_CTRL);
	187	pio_xfer_ctrl &= ~REQUEST_COUNT_MSK;
	188	pio_xfer_ctrl \|= ctrl->xfer.rem_bytes;
	189	writel(pio_xfer_ctrl, ctrl->base + PIO_XFER_CTRL);
	190	}
	191
	192	static void qcom_qspi_pio_xfer(struct qcom_qspi *ctrl)
	193	{
	194	u32 ints;
	195
	196	qcom_qspi_pio_xfer_cfg(ctrl);
	197
	198	/* Ack any previous interrupts that might be hanging around */
	199	writel(QSPI_ALL_IRQS, ctrl->base + MSTR_INT_STATUS);
	200
	201	/* Setup new interrupts */
	202	if (ctrl->xfer.dir == QSPI_WRITE)
	203	ints = QSPI_ERR_IRQS \| WR_FIFO_EMPTY;
	204	else
	205	ints = QSPI_ERR_IRQS \| RESP_FIFO_RDY;
	206	writel(ints, ctrl->base + MSTR_INT_EN);
207
208	/* Kick off the transfer */
209	qcom_qspi_pio_xfer_ctrl(ctrl);
210	}
211
212	static void qcom_qspi_handle_err(struct spi_master *master,
213	struct spi_message *msg)
214	{
215	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
216	unsigned long flags;
217
218	spin_lock_irqsave(&ctrl->lock, flags);
219	writel(0, ctrl->base + MSTR_INT_EN);
220	ctrl->xfer.rem_bytes = 0;
221	spin_unlock_irqrestore(&ctrl->lock, flags);
222	}
223
224	static int qcom_qspi_transfer_one(struct spi_master *master,
225	struct spi_device *slv,
226	struct spi_transfer *xfer)
227	{
228	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
229	int ret;
230	unsigned long speed_hz;
231	unsigned long flags;
232
233	speed_hz = slv->max_speed_hz;
234	if (xfer->speed_hz)
235	speed_hz = xfer->speed_hz;
236
237	/* In regular operation (SBL_EN=1) core must be 4x transfer clock */
238	ret = clk_set_rate(ctrl->clks[QSPI_CLK_CORE].clk, speed_hz * 4);
239	if (ret) {
240	dev_err(ctrl->dev, "Failed to set core clk %d\n", ret);
241	return ret;
242	}
243
244	spin_lock_irqsave(&ctrl->lock, flags);
245
246	/* We are half duplex, so either rx or tx will be set */
247	if (xfer->rx_buf) {
248	ctrl->xfer.dir = QSPI_READ;
249	ctrl->xfer.buswidth = xfer->rx_nbits;
250	ctrl->xfer.rx_buf = xfer->rx_buf;
251	} else {
252	ctrl->xfer.dir = QSPI_WRITE;
253	ctrl->xfer.buswidth = xfer->tx_nbits;
254	ctrl->xfer.tx_buf = xfer->tx_buf;
255	}
256	ctrl->xfer.is_last = list_is_last(&xfer->transfer_list,
257	&master->cur_msg->transfers);
258	ctrl->xfer.rem_bytes = xfer->len;
259	qcom_qspi_pio_xfer(ctrl);
260
261	spin_unlock_irqrestore(&ctrl->lock, flags);
262
263	/* We'll call spi_finalize_current_transfer() when done */
264	return 1;
265	}
266
267	static int qcom_qspi_prepare_message(struct spi_master *master,
268	struct spi_message *message)
269	{
270	u32 mstr_cfg;
271	struct qcom_qspi *ctrl;
272	int tx_data_oe_delay = 1;
273	int tx_data_delay = 1;
274	unsigned long flags;
275
276	ctrl = spi_master_get_devdata(master);
277	spin_lock_irqsave(&ctrl->lock, flags);
278
279	mstr_cfg = readl(ctrl->base + MSTR_CONFIG);
280	mstr_cfg &= ~CHIP_SELECT_NUM;
281	if (message->spi->chip_select)
282	mstr_cfg \|= CHIP_SELECT_NUM;
283
284	mstr_cfg \|= FB_CLK_EN \| PIN_WPN \| PIN_HOLDN \| SBL_EN \| FULL_CYCLE_MODE;
285	mstr_cfg &= ~(SPI_MODE_MSK \| TX_DATA_OE_DELAY_MSK \| TX_DATA_DELAY_MSK);
286	mstr_cfg \|= message->spi->mode << SPI_MODE_SHFT;
287	mstr_cfg \|= tx_data_oe_delay << TX_DATA_OE_DELAY_SHFT;
288	mstr_cfg \|= tx_data_delay << TX_DATA_DELAY_SHFT;
289	mstr_cfg &= ~DMA_ENABLE;
290
291	writel(mstr_cfg, ctrl->base + MSTR_CONFIG);
292	spin_unlock_irqrestore(&ctrl->lock, flags);
293
294	return 0;
295	}
296
297	static irqreturn_t pio_read(struct qcom_qspi *ctrl)
298	{
299	u32 rd_fifo_status;
300	u32 rd_fifo;
301	unsigned int wr_cnts;
302	unsigned int bytes_to_read;
303	unsigned int words_to_read;
304	u32 *word_buf;
305	u8 *byte_buf;
306	int i;
307
308	rd_fifo_status = readl(ctrl->base + RD_FIFO_STATUS);
309
310	if (!(rd_fifo_status & FIFO_RDY)) {
311	dev_dbg(ctrl->dev, "Spurious IRQ %#x\n", rd_fifo_status);
312	return IRQ_NONE;
313	}
314
315	wr_cnts = (rd_fifo_status & WR_CNTS_MSK) >> WR_CNTS_SHFT;
316	wr_cnts = min(wr_cnts, ctrl->xfer.rem_bytes);
317
318	words_to_read = wr_cnts / QSPI_BYTES_PER_WORD;
319	bytes_to_read = wr_cnts % QSPI_BYTES_PER_WORD;
320
321	if (words_to_read) {
322	word_buf = ctrl->xfer.rx_buf;
323	ctrl->xfer.rem_bytes -= words_to_read * QSPI_BYTES_PER_WORD;
324	ioread32_rep(ctrl->base + RD_FIFO, word_buf, words_to_read);
325	ctrl->xfer.rx_buf = word_buf + words_to_read;
326	}
327
328	if (bytes_to_read) {
329	byte_buf = ctrl->xfer.rx_buf;
330	rd_fifo = readl(ctrl->base + RD_FIFO);
331	ctrl->xfer.rem_bytes -= bytes_to_read;
332	for (i = 0; i < bytes_to_read; i++)
333	byte_buf++ = rd_fifo >> (i BITS_PER_BYTE);
334	ctrl->xfer.rx_buf = byte_buf;
335	}
336
337	return IRQ_HANDLED;
338	}
339
340	static irqreturn_t pio_write(struct qcom_qspi *ctrl)
341	{
342	const void *xfer_buf = ctrl->xfer.tx_buf;
343	const int *word_buf;
344	const char *byte_buf;
345	unsigned int wr_fifo_bytes;
346	unsigned int wr_fifo_words;
347	unsigned int wr_size;
348	unsigned int rem_words;
349
350	wr_fifo_bytes = readl(ctrl->base + PIO_XFER_STATUS);
351	wr_fifo_bytes >>= WR_FIFO_BYTES_SHFT;
352
353	if (ctrl->xfer.rem_bytes < QSPI_BYTES_PER_WORD) {
354	/* Process the last 1-3 bytes */
355	wr_size = min(wr_fifo_bytes, ctrl->xfer.rem_bytes);
356	ctrl->xfer.rem_bytes -= wr_size;
357
358	byte_buf = xfer_buf;
359	while (wr_size--)
360	writel(*byte_buf++,
361	ctrl->base + PIO_DATAOUT_1B);
362	ctrl->xfer.tx_buf = byte_buf;
363	} else {
364	/*
365	* Process all the whole words; to keep things simple we'll
366	* just wait for the next interrupt to handle the last 1-3
367	* bytes if we don't have an even number of words.
368	*/
369	rem_words = ctrl->xfer.rem_bytes / QSPI_BYTES_PER_WORD;
370	wr_fifo_words = wr_fifo_bytes / QSPI_BYTES_PER_WORD;
371
372	wr_size = min(rem_words, wr_fifo_words);
373	ctrl->xfer.rem_bytes -= wr_size * QSPI_BYTES_PER_WORD;
374
375	word_buf = xfer_buf;
376	iowrite32_rep(ctrl->base + PIO_DATAOUT_4B, word_buf, wr_size);
377	ctrl->xfer.tx_buf = word_buf + wr_size;
378
379	}
380
381	return IRQ_HANDLED;
382	}
383
384	static irqreturn_t qcom_qspi_irq(int irq, void *dev_id)
385	{
386	u32 int_status;
387	struct qcom_qspi *ctrl = dev_id;
388	irqreturn_t ret = IRQ_NONE;
389	unsigned long flags;
390
391	spin_lock_irqsave(&ctrl->lock, flags);
392
393	int_status = readl(ctrl->base + MSTR_INT_STATUS);
394	writel(int_status, ctrl->base + MSTR_INT_STATUS);
395
396	if (ctrl->xfer.dir == QSPI_WRITE) {
397	if (int_status & WR_FIFO_EMPTY)
398	ret = pio_write(ctrl);
399	} else {
400	if (int_status & RESP_FIFO_RDY)
401	ret = pio_read(ctrl);
402	}
403
404	if (int_status & QSPI_ERR_IRQS) {
405	if (int_status & RESP_FIFO_UNDERRUN)
406	dev_err(ctrl->dev, "IRQ error: FIFO underrun\n");
407	if (int_status & WR_FIFO_OVERRUN)
408	dev_err(ctrl->dev, "IRQ error: FIFO overrun\n");
409	if (int_status & HRESP_FROM_NOC_ERR)
410	dev_err(ctrl->dev, "IRQ error: NOC response error\n");
411	ret = IRQ_HANDLED;
412	}
413
414	if (!ctrl->xfer.rem_bytes) {
415	writel(0, ctrl->base + MSTR_INT_EN);
416	spi_finalize_current_transfer(dev_get_drvdata(ctrl->dev));
417	}
418
419	spin_unlock_irqrestore(&ctrl->lock, flags);
420	return ret;
421	}
422
423	static int qcom_qspi_probe(struct platform_device *pdev)
424	{
425	int ret;
426	struct device *dev;
04000dc6 GM	427	struct spi_master *master;
	428	struct qcom_qspi *ctrl;
	429
	430	dev = &pdev->dev;
	431
	432	master = spi_alloc_master(dev, sizeof(*ctrl));
	433	if (!master)
	434	return -ENOMEM;
	435
	436	platform_set_drvdata(pdev, master);
	437
	438	ctrl = spi_master_get_devdata(master);
	439
	440	spin_lock_init(&ctrl->lock);
	441	ctrl->dev = dev;
e0ea3cc2	442	ctrl->base = devm_platform_ioremap_resource(pdev, 0);
04000dc6 GM	443	if (IS_ERR(ctrl->base)) {
	444	ret = PTR_ERR(ctrl->base);
	445	goto exit_probe_master_put;
	446	}
	447
	448	ctrl->clks[QSPI_CLK_CORE].id = "core";
	449	ctrl->clks[QSPI_CLK_IFACE].id = "iface";
	450	ret = devm_clk_bulk_get(dev, QSPI_NUM_CLKS, ctrl->clks);
	451	if (ret)
	452	goto exit_probe_master_put;
	453
	454	ret = platform_get_irq(pdev, 0);
6b8ac10e	455	if (ret < 0)
04000dc6	456	goto exit_probe_master_put;
04000dc6 GM	457	ret = devm_request_irq(dev, ret, qcom_qspi_irq,
	458	IRQF_TRIGGER_HIGH, dev_name(dev), ctrl);
	459	if (ret) {
	460	dev_err(dev, "Failed to request irq %d\n", ret);
	461	goto exit_probe_master_put;
	462	}
	463
	464	master->max_speed_hz = 300000000;
	465	master->num_chipselect = QSPI_NUM_CS;
	466	master->bus_num = -1;
	467	master->dev.of_node = pdev->dev.of_node;
	468	master->mode_bits = SPI_MODE_0 \|
	469	SPI_TX_DUAL \| SPI_RX_DUAL \|
	470	SPI_TX_QUAD \| SPI_RX_QUAD;
	471	master->flags = SPI_MASTER_HALF_DUPLEX;
	472	master->prepare_message = qcom_qspi_prepare_message;
	473	master->transfer_one = qcom_qspi_transfer_one;
	474	master->handle_err = qcom_qspi_handle_err;
	475	master->auto_runtime_pm = true;
	476
	477	pm_runtime_enable(dev);
	478
	479	ret = spi_register_master(master);
	480	if (!ret)
	481	return 0;
	482
	483	pm_runtime_disable(dev);
	484
	485	exit_probe_master_put:
	486	spi_master_put(master);
	487
	488	return ret;
	489	}
	490
	491	static int qcom_qspi_remove(struct platform_device *pdev)
	492	{
	493	struct spi_master *master = platform_get_drvdata(pdev);
	494
	495	/* Unregister _before_ disabling pm_runtime() so we stop transfers */
	496	spi_unregister_master(master);
	497
	498	pm_runtime_disable(&pdev->dev);
	499
	500	return 0;
	501	}
	502
	503	static int __maybe_unused qcom_qspi_runtime_suspend(struct device *dev)
	504	{
	505	struct spi_master *master = dev_get_drvdata(dev);
	506	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
	507
	508	clk_bulk_disable_unprepare(QSPI_NUM_CLKS, ctrl->clks);
	509
	510	return 0;
	511	}
	512
	513	static int __maybe_unused qcom_qspi_runtime_resume(struct device *dev)
	514	{
	515	struct spi_master *master = dev_get_drvdata(dev);
	516	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
	517
	518	return clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks);
	519	}
	520
521	static int __maybe_unused qcom_qspi_suspend(struct device *dev)
522	{
523	struct spi_master *master = dev_get_drvdata(dev);
524	int ret;
525
526	ret = spi_master_suspend(master);
527	if (ret)
528	return ret;
529
530	ret = pm_runtime_force_suspend(dev);
531	if (ret)
532	spi_master_resume(master);
533
534	return ret;
535	}
536
537	static int __maybe_unused qcom_qspi_resume(struct device *dev)
538	{
539	struct spi_master *master = dev_get_drvdata(dev);
540	int ret;
541
542	ret = pm_runtime_force_resume(dev);
543	if (ret)
544	return ret;
545
546	ret = spi_master_resume(master);
547	if (ret)
548	pm_runtime_force_suspend(dev);
549
550	return ret;
551	}
552
553	static const struct dev_pm_ops qcom_qspi_dev_pm_ops = {
554	SET_RUNTIME_PM_OPS(qcom_qspi_runtime_suspend,
555	qcom_qspi_runtime_resume, NULL)
556	SET_SYSTEM_SLEEP_PM_OPS(qcom_qspi_suspend, qcom_qspi_resume)
557	};
558
559	static const struct of_device_id qcom_qspi_dt_match[] = {
560	{ .compatible = "qcom,qspi-v1", },
561	{ }
562	};
563	MODULE_DEVICE_TABLE(of, qcom_qspi_dt_match);
564
565	static struct platform_driver qcom_qspi_driver = {
566	.driver = {
567	.name = "qcom_qspi",
568	.pm = &qcom_qspi_dev_pm_ops,
569	.of_match_table = qcom_qspi_dt_match,
570	},
571	.probe = qcom_qspi_probe,
572	.remove = qcom_qspi_remove,
573	};
574	module_platform_driver(qcom_qspi_driver);
575
576	MODULE_DESCRIPTION("SPI driver for QSPI cores");
577	MODULE_LICENSE("GPL v2");