Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 594 insertions, 0 deletions

diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
new file mode 100644
index 000000000..68cfc351b
--- /dev/null
+++ b/drivers/spi/spi-axi-spi-engine.c
@@ -0,0 +1,594 @@
+/*
+ * SPI-Engine SPI controller driver
+ * Copyright 2015 Analog Devices Inc.
+ *  Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#define SPI_ENGINE_VERSION_MAJOR(x)	((x >> 16) & 0xff)
+#define SPI_ENGINE_VERSION_MINOR(x)	((x >> 8) & 0xff)
+#define SPI_ENGINE_VERSION_PATCH(x)	(x & 0xff)
+
+#define SPI_ENGINE_REG_VERSION			0x00
+
+#define SPI_ENGINE_REG_RESET			0x40
+
+#define SPI_ENGINE_REG_INT_ENABLE		0x80
+#define SPI_ENGINE_REG_INT_PENDING		0x84
+#define SPI_ENGINE_REG_INT_SOURCE		0x88
+
+#define SPI_ENGINE_REG_SYNC_ID			0xc0
+
+#define SPI_ENGINE_REG_CMD_FIFO_ROOM		0xd0
+#define SPI_ENGINE_REG_SDO_FIFO_ROOM		0xd4
+#define SPI_ENGINE_REG_SDI_FIFO_LEVEL		0xd8
+
+#define SPI_ENGINE_REG_CMD_FIFO			0xe0
+#define SPI_ENGINE_REG_SDO_DATA_FIFO		0xe4
+#define SPI_ENGINE_REG_SDI_DATA_FIFO		0xe8
+#define SPI_ENGINE_REG_SDI_DATA_FIFO_PEEK	0xec
+
+#define SPI_ENGINE_INT_CMD_ALMOST_EMPTY		BIT(0)
+#define SPI_ENGINE_INT_SDO_ALMOST_EMPTY		BIT(1)
+#define SPI_ENGINE_INT_SDI_ALMOST_FULL		BIT(2)
+#define SPI_ENGINE_INT_SYNC			BIT(3)
+
+#define SPI_ENGINE_CONFIG_CPHA			BIT(0)
+#define SPI_ENGINE_CONFIG_CPOL			BIT(1)
+#define SPI_ENGINE_CONFIG_3WIRE			BIT(2)
+
+#define SPI_ENGINE_INST_TRANSFER		0x0
+#define SPI_ENGINE_INST_ASSERT			0x1
+#define SPI_ENGINE_INST_WRITE			0x2
+#define SPI_ENGINE_INST_MISC			0x3
+
+#define SPI_ENGINE_CMD_REG_CLK_DIV		0x0
+#define SPI_ENGINE_CMD_REG_CONFIG		0x1
+
+#define SPI_ENGINE_MISC_SYNC			0x0
+#define SPI_ENGINE_MISC_SLEEP			0x1
+
+#define SPI_ENGINE_TRANSFER_WRITE		0x1
+#define SPI_ENGINE_TRANSFER_READ		0x2
+
+#define SPI_ENGINE_CMD(inst, arg1, arg2) \
+	(((inst) << 12) | ((arg1) << 8) | (arg2))
+
+#define SPI_ENGINE_CMD_TRANSFER(flags, n) \
+	SPI_ENGINE_CMD(SPI_ENGINE_INST_TRANSFER, (flags), (n))
+#define SPI_ENGINE_CMD_ASSERT(delay, cs) \
+	SPI_ENGINE_CMD(SPI_ENGINE_INST_ASSERT, (delay), (cs))
+#define SPI_ENGINE_CMD_WRITE(reg, val) \
+	SPI_ENGINE_CMD(SPI_ENGINE_INST_WRITE, (reg), (val))
+#define SPI_ENGINE_CMD_SLEEP(delay) \
+	SPI_ENGINE_CMD(SPI_ENGINE_INST_MISC, SPI_ENGINE_MISC_SLEEP, (delay))
+#define SPI_ENGINE_CMD_SYNC(id) \
+	SPI_ENGINE_CMD(SPI_ENGINE_INST_MISC, SPI_ENGINE_MISC_SYNC, (id))
+
+struct spi_engine_program {
+	unsigned int length;
+	uint16_t instructions[];
+};
+
+struct spi_engine {
+	struct clk *clk;
+	struct clk *ref_clk;
+
+	spinlock_t lock;
+
+	void __iomem *base;
+
+	struct spi_message *msg;
+	struct spi_engine_program *p;
+	unsigned cmd_length;
+	const uint16_t *cmd_buf;
+
+	struct spi_transfer *tx_xfer;
+	unsigned int tx_length;
+	const uint8_t *tx_buf;
+
+	struct spi_transfer *rx_xfer;
+	unsigned int rx_length;
+	uint8_t *rx_buf;
+
+	unsigned int sync_id;
+	unsigned int completed_id;
+
+	unsigned int int_enable;
+};
+
+static void spi_engine_program_add_cmd(struct spi_engine_program *p,
+	bool dry, uint16_t cmd)
+{
+	if (!dry)
+		p->instructions[p->length] = cmd;
+	p->length++;
+}
+
+static unsigned int spi_engine_get_config(struct spi_device *spi)
+{
+	unsigned int config = 0;
+
+	if (spi->mode & SPI_CPOL)
+		config |= SPI_ENGINE_CONFIG_CPOL;
+	if (spi->mode & SPI_CPHA)
+		config |= SPI_ENGINE_CONFIG_CPHA;
+	if (spi->mode & SPI_3WIRE)
+		config |= SPI_ENGINE_CONFIG_3WIRE;
+
+	return config;
+}
+
+static unsigned int spi_engine_get_clk_div(struct spi_engine *spi_engine,
+	struct spi_device *spi, struct spi_transfer *xfer)
+{
+	unsigned int clk_div;
+
+	clk_div = DIV_ROUND_UP(clk_get_rate(spi_engine->ref_clk),
+		xfer->speed_hz * 2);
+	if (clk_div > 255)
+		clk_div = 255;
+	else if (clk_div > 0)
+		clk_div -= 1;
+
+	return clk_div;
+}
+
+static void spi_engine_gen_xfer(struct spi_engine_program *p, bool dry,
+	struct spi_transfer *xfer)
+{
+	unsigned int len = xfer->len;
+
+	while (len) {
+		unsigned int n = min(len, 256U);
+		unsigned int flags = 0;
+
+		if (xfer->tx_buf)
+			flags |= SPI_ENGINE_TRANSFER_WRITE;
+		if (xfer->rx_buf)
+			flags |= SPI_ENGINE_TRANSFER_READ;
+
+		spi_engine_program_add_cmd(p, dry,
+			SPI_ENGINE_CMD_TRANSFER(flags, n - 1));
+		len -= n;
+	}
+}
+
+static void spi_engine_gen_sleep(struct spi_engine_program *p, bool dry,
+	struct spi_engine *spi_engine, unsigned int clk_div, unsigned int delay)
+{
+	unsigned int spi_clk = clk_get_rate(spi_engine->ref_clk);
+	unsigned int t;
+
+	if (delay == 0)
+		return;
+
+	t = DIV_ROUND_UP(delay * spi_clk, (clk_div + 1) * 2);
+	while (t) {
+		unsigned int n = min(t, 256U);
+
+		spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_SLEEP(n - 1));
+		t -= n;
+	}
+}
+
+static void spi_engine_gen_cs(struct spi_engine_program *p, bool dry,
+		struct spi_device *spi, bool assert)
+{
+	unsigned int mask = 0xff;
+
+	if (assert)
+		mask ^= BIT(spi->chip_select);
+
+	spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_ASSERT(1, mask));
+}
+
+static int spi_engine_compile_message(struct spi_engine *spi_engine,
+	struct spi_message *msg, bool dry, struct spi_engine_program *p)
+{
+	struct spi_device *spi = msg->spi;
+	struct spi_transfer *xfer;
+	int clk_div, new_clk_div;
+	bool cs_change = true;
+
+	clk_div = -1;
+
+	spi_engine_program_add_cmd(p, dry,
+		SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CONFIG,
+			spi_engine_get_config(spi)));
+
+	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+		new_clk_div = spi_engine_get_clk_div(spi_engine, spi, xfer);
+		if (new_clk_div != clk_div) {
+			clk_div = new_clk_div;
+			spi_engine_program_add_cmd(p, dry,
+				SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CLK_DIV,
+					clk_div));
+		}
+
+		if (cs_change)
+			spi_engine_gen_cs(p, dry, spi, true);
+
+		spi_engine_gen_xfer(p, dry, xfer);
+		spi_engine_gen_sleep(p, dry, spi_engine, clk_div,
+			xfer->delay_usecs);
+
+		cs_change = xfer->cs_change;
+		if (list_is_last(&xfer->transfer_list, &msg->transfers))
+			cs_change = !cs_change;
+
+		if (cs_change)
+			spi_engine_gen_cs(p, dry, spi, false);
+	}
+
+	return 0;
+}
+
+static void spi_engine_xfer_next(struct spi_engine *spi_engine,
+	struct spi_transfer **_xfer)
+{
+	struct spi_message *msg = spi_engine->msg;
+	struct spi_transfer *xfer = *_xfer;
+
+	if (!xfer) {
+		xfer = list_first_entry(&msg->transfers,
+			struct spi_transfer, transfer_list);
+	} else if (list_is_last(&xfer->transfer_list, &msg->transfers)) {
+		xfer = NULL;
+	} else {
+		xfer = list_next_entry(xfer, transfer_list);
+	}
+
+	*_xfer = xfer;
+}
+
+static void spi_engine_tx_next(struct spi_engine *spi_engine)
+{
+	struct spi_transfer *xfer = spi_engine->tx_xfer;
+
+	do {
+		spi_engine_xfer_next(spi_engine, &xfer);
+	} while (xfer && !xfer->tx_buf);
+
+	spi_engine->tx_xfer = xfer;
+	if (xfer) {
+		spi_engine->tx_length = xfer->len;
+		spi_engine->tx_buf = xfer->tx_buf;
+	} else {
+		spi_engine->tx_buf = NULL;
+	}
+}
+
+static void spi_engine_rx_next(struct spi_engine *spi_engine)
+{
+	struct spi_transfer *xfer = spi_engine->rx_xfer;
+
+	do {
+		spi_engine_xfer_next(spi_engine, &xfer);
+	} while (xfer && !xfer->rx_buf);
+
+	spi_engine->rx_xfer = xfer;
+	if (xfer) {
+		spi_engine->rx_length = xfer->len;
+		spi_engine->rx_buf = xfer->rx_buf;
+	} else {
+		spi_engine->rx_buf = NULL;
+	}
+}
+
+static bool spi_engine_write_cmd_fifo(struct spi_engine *spi_engine)
+{
+	void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_CMD_FIFO;
+	unsigned int n, m, i;
+	const uint16_t *buf;
+
+	n = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_CMD_FIFO_ROOM);
+	while (n && spi_engine->cmd_length) {
+		m = min(n, spi_engine->cmd_length);
+		buf = spi_engine->cmd_buf;
+		for (i = 0; i < m; i++)
+			writel_relaxed(buf[i], addr);
+		spi_engine->cmd_buf += m;
+		spi_engine->cmd_length -= m;
+		n -= m;
+	}
+
+	return spi_engine->cmd_length != 0;
+}
+
+static bool spi_engine_write_tx_fifo(struct spi_engine *spi_engine)
+{
+	void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_SDO_DATA_FIFO;
+	unsigned int n, m, i;
+	const uint8_t *buf;
+
+	n = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_SDO_FIFO_ROOM);
+	while (n && spi_engine->tx_length) {
+		m = min(n, spi_engine->tx_length);
+		buf = spi_engine->tx_buf;
+		for (i = 0; i < m; i++)
+			writel_relaxed(buf[i], addr);
+		spi_engine->tx_buf += m;
+		spi_engine->tx_length -= m;
+		n -= m;
+		if (spi_engine->tx_length == 0)
+			spi_engine_tx_next(spi_engine);
+	}
+
+	return spi_engine->tx_length != 0;
+}
+
+static bool spi_engine_read_rx_fifo(struct spi_engine *spi_engine)
+{
+	void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_SDI_DATA_FIFO;
+	unsigned int n, m, i;
+	uint8_t *buf;
+
+	n = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_SDI_FIFO_LEVEL);
+	while (n && spi_engine->rx_length) {
+		m = min(n, spi_engine->rx_length);
+		buf = spi_engine->rx_buf;
+		for (i = 0; i < m; i++)
+			buf[i] = readl_relaxed(addr);
+		spi_engine->rx_buf += m;
+		spi_engine->rx_length -= m;
+		n -= m;
+		if (spi_engine->rx_length == 0)
+			spi_engine_rx_next(spi_engine);
+	}
+
+	return spi_engine->rx_length != 0;
+}
+
+static irqreturn_t spi_engine_irq(int irq, void *devid)
+{
+	struct spi_master *master = devid;
+	struct spi_engine *spi_engine = spi_master_get_devdata(master);
+	unsigned int disable_int = 0;
+	unsigned int pending;
+
+	pending = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_INT_PENDING);
+
+	if (pending & SPI_ENGINE_INT_SYNC) {
+		writel_relaxed(SPI_ENGINE_INT_SYNC,
+			spi_engine->base + SPI_ENGINE_REG_INT_PENDING);
+		spi_engine->completed_id = readl_relaxed(
+			spi_engine->base + SPI_ENGINE_REG_SYNC_ID);
+	}
+
+	spin_lock(&spi_engine->lock);
+
+	if (pending & SPI_ENGINE_INT_CMD_ALMOST_EMPTY) {
+		if (!spi_engine_write_cmd_fifo(spi_engine))
+			disable_int |= SPI_ENGINE_INT_CMD_ALMOST_EMPTY;
+	}
+
+	if (pending & SPI_ENGINE_INT_SDO_ALMOST_EMPTY) {
+		if (!spi_engine_write_tx_fifo(spi_engine))
+			disable_int |= SPI_ENGINE_INT_SDO_ALMOST_EMPTY;
+	}
+
+	if (pending & (SPI_ENGINE_INT_SDI_ALMOST_FULL | SPI_ENGINE_INT_SYNC)) {
+		if (!spi_engine_read_rx_fifo(spi_engine))
+			disable_int |= SPI_ENGINE_INT_SDI_ALMOST_FULL;
+	}
+
+	if (pending & SPI_ENGINE_INT_SYNC) {
+		if (spi_engine->msg &&
+		    spi_engine->completed_id == spi_engine->sync_id) {
+			struct spi_message *msg = spi_engine->msg;
+
+			kfree(spi_engine->p);
+			msg->status = 0;
+			msg->actual_length = msg->frame_length;
+			spi_engine->msg = NULL;
+			spi_finalize_current_message(master);
+			disable_int |= SPI_ENGINE_INT_SYNC;
+		}
+	}
+
+	if (disable_int) {
+		spi_engine->int_enable &= ~disable_int;
+		writel_relaxed(spi_engine->int_enable,
+			spi_engine->base + SPI_ENGINE_REG_INT_ENABLE);
+	}
+
+	spin_unlock(&spi_engine->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int spi_engine_transfer_one_message(struct spi_master *master,
+	struct spi_message *msg)
+{
+	struct spi_engine_program p_dry, *p;
+	struct spi_engine *spi_engine = spi_master_get_devdata(master);
+	unsigned int int_enable = 0;
+	unsigned long flags;
+	size_t size;
+
+	p_dry.length = 0;
+	spi_engine_compile_message(spi_engine, msg, true, &p_dry);
+
+	size = sizeof(*p->instructions) * (p_dry.length + 1);
+	p = kzalloc(sizeof(*p) + size, GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+	spi_engine_compile_message(spi_engine, msg, false, p);
+
+	spin_lock_irqsave(&spi_engine->lock, flags);
+	spi_engine->sync_id = (spi_engine->sync_id + 1) & 0xff;
+	spi_engine_program_add_cmd(p, false,
+		SPI_ENGINE_CMD_SYNC(spi_engine->sync_id));
+
+	spi_engine->msg = msg;
+	spi_engine->p = p;
+
+	spi_engine->cmd_buf = p->instructions;
+	spi_engine->cmd_length = p->length;
+	if (spi_engine_write_cmd_fifo(spi_engine))
+		int_enable |= SPI_ENGINE_INT_CMD_ALMOST_EMPTY;
+
+	spi_engine_tx_next(spi_engine);
+	if (spi_engine_write_tx_fifo(spi_engine))
+		int_enable |= SPI_ENGINE_INT_SDO_ALMOST_EMPTY;
+
+	spi_engine_rx_next(spi_engine);
+	if (spi_engine->rx_length != 0)
+		int_enable |= SPI_ENGINE_INT_SDI_ALMOST_FULL;
+
+	int_enable |= SPI_ENGINE_INT_SYNC;
+
+	writel_relaxed(int_enable,
+		spi_engine->base + SPI_ENGINE_REG_INT_ENABLE);
+	spi_engine->int_enable = int_enable;
+	spin_unlock_irqrestore(&spi_engine->lock, flags);
+
+	return 0;
+}
+
+static int spi_engine_probe(struct platform_device *pdev)
+{
+	struct spi_engine *spi_engine;
+	struct spi_master *master;
+	unsigned int version;
+	struct resource *res;
+	int irq;
+	int ret;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0)
+		return -ENXIO;
+
+	spi_engine = devm_kzalloc(&pdev->dev, sizeof(*spi_engine), GFP_KERNEL);
+	if (!spi_engine)
+		return -ENOMEM;
+
+	master = spi_alloc_master(&pdev->dev, 0);
+	if (!master)
+		return -ENOMEM;
+
+	spi_master_set_devdata(master, spi_engine);
+
+	spin_lock_init(&spi_engine->lock);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	spi_engine->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(spi_engine->base)) {
+		ret = PTR_ERR(spi_engine->base);
+		goto err_put_master;
+	}
+
+	version = readl(spi_engine->base + SPI_ENGINE_REG_VERSION);
+	if (SPI_ENGINE_VERSION_MAJOR(version) != 1) {
+		dev_err(&pdev->dev, "Unsupported peripheral version %u.%u.%c\n",
+			SPI_ENGINE_VERSION_MAJOR(version),
+			SPI_ENGINE_VERSION_MINOR(version),
+			SPI_ENGINE_VERSION_PATCH(version));
+		ret = -ENODEV;
+		goto err_put_master;
+	}
+
+	spi_engine->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
+	if (IS_ERR(spi_engine->clk)) {
+		ret = PTR_ERR(spi_engine->clk);
+		goto err_put_master;
+	}
+
+	spi_engine->ref_clk = devm_clk_get(&pdev->dev, "spi_clk");
+	if (IS_ERR(spi_engine->ref_clk)) {
+		ret = PTR_ERR(spi_engine->ref_clk);
+		goto err_put_master;
+	}
+
+	ret = clk_prepare_enable(spi_engine->clk);
+	if (ret)
+		goto err_put_master;
+
+	ret = clk_prepare_enable(spi_engine->ref_clk);
+	if (ret)
+		goto err_clk_disable;
+
+	writel_relaxed(0x00, spi_engine->base + SPI_ENGINE_REG_RESET);
+	writel_relaxed(0xff, spi_engine->base + SPI_ENGINE_REG_INT_PENDING);
+	writel_relaxed(0x00, spi_engine->base + SPI_ENGINE_REG_INT_ENABLE);
+
+	ret = request_irq(irq, spi_engine_irq, 0, pdev->name, master);
+	if (ret)
+		goto err_ref_clk_disable;
+
+	master->dev.of_node = pdev->dev.of_node;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE;
+	master->bits_per_word_mask = SPI_BPW_MASK(8);
+	master->max_speed_hz = clk_get_rate(spi_engine->ref_clk) / 2;
+	master->transfer_one_message = spi_engine_transfer_one_message;
+	master->num_chipselect = 8;
+
+	ret = spi_register_master(master);
+	if (ret)
+		goto err_free_irq;
+
+	platform_set_drvdata(pdev, master);
+
+	return 0;
+err_free_irq:
+	free_irq(irq, master);
+err_ref_clk_disable:
+	clk_disable_unprepare(spi_engine->ref_clk);
+err_clk_disable:
+	clk_disable_unprepare(spi_engine->clk);
+err_put_master:
+	spi_master_put(master);
+	return ret;
+}
+
+static int spi_engine_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
+	struct spi_engine *spi_engine = spi_master_get_devdata(master);
+	int irq = platform_get_irq(pdev, 0);
+
+	spi_unregister_master(master);
+
+	free_irq(irq, master);
+
+	spi_master_put(master);
+
+	writel_relaxed(0xff, spi_engine->base + SPI_ENGINE_REG_INT_PENDING);
+	writel_relaxed(0x00, spi_engine->base + SPI_ENGINE_REG_INT_ENABLE);
+	writel_relaxed(0x01, spi_engine->base + SPI_ENGINE_REG_RESET);
+
+	clk_disable_unprepare(spi_engine->ref_clk);
+	clk_disable_unprepare(spi_engine->clk);
+
+	return 0;
+}
+
+static const struct of_device_id spi_engine_match_table[] = {
+	{ .compatible = "adi,axi-spi-engine-1.00.a" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, spi_engine_match_table);
+
+static struct platform_driver spi_engine_driver = {
+	.probe = spi_engine_probe,
+	.remove = spi_engine_remove,
+	.driver = {
+		.name = "spi-engine",
+		.of_match_table = spi_engine_match_table,
+	},
+};
+module_platform_driver(spi_engine_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices SPI engine peripheral driver");
+MODULE_LICENSE("GPL");