ASR_BASE

Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/nvmem/imx-ocotp.c b/marvell/linux/drivers/nvmem/imx-ocotp.c
new file mode 100644
index 0000000..3297ced
--- /dev/null
+++ b/marvell/linux/drivers/nvmem/imx-ocotp.c
@@ -0,0 +1,550 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * i.MX6 OCOTP fusebox driver
+ *
+ * Copyright (c) 2015 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
+ *
+ * Based on the barebox ocotp driver,
+ * Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>,
+ *	Orex Computed Radiography
+ *
+ * Write support based on the fsl_otp driver,
+ * Copyright (C) 2010-2013 Freescale Semiconductor, Inc
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+
+#define IMX_OCOTP_OFFSET_B0W0		0x400 /* Offset from base address of the
+					       * OTP Bank0 Word0
+					       */
+#define IMX_OCOTP_OFFSET_PER_WORD	0x10  /* Offset between the start addr
+					       * of two consecutive OTP words.
+					       */
+
+#define IMX_OCOTP_ADDR_CTRL		0x0000
+#define IMX_OCOTP_ADDR_CTRL_SET		0x0004
+#define IMX_OCOTP_ADDR_CTRL_CLR		0x0008
+#define IMX_OCOTP_ADDR_TIMING		0x0010
+#define IMX_OCOTP_ADDR_DATA0		0x0020
+#define IMX_OCOTP_ADDR_DATA1		0x0030
+#define IMX_OCOTP_ADDR_DATA2		0x0040
+#define IMX_OCOTP_ADDR_DATA3		0x0050
+
+#define IMX_OCOTP_BM_CTRL_ADDR		0x000000FF
+#define IMX_OCOTP_BM_CTRL_BUSY		0x00000100
+#define IMX_OCOTP_BM_CTRL_ERROR		0x00000200
+#define IMX_OCOTP_BM_CTRL_REL_SHADOWS	0x00000400
+
+#define TIMING_STROBE_PROG_US		10	/* Min time to blow a fuse */
+#define TIMING_STROBE_READ_NS		37	/* Min time before read */
+#define TIMING_RELAX_NS			17
+#define DEF_FSOURCE			1001	/* > 1000 ns */
+#define DEF_STROBE_PROG			10000	/* IPG clocks */
+#define IMX_OCOTP_WR_UNLOCK		0x3E770000
+#define IMX_OCOTP_READ_LOCKED_VAL	0xBADABADA
+
+static DEFINE_MUTEX(ocotp_mutex);
+
+struct ocotp_priv {
+	struct device *dev;
+	struct clk *clk;
+	void __iomem *base;
+	const struct ocotp_params *params;
+	struct nvmem_config *config;
+};
+
+struct ocotp_params {
+	unsigned int nregs;
+	unsigned int bank_address_words;
+	void (*set_timing)(struct ocotp_priv *priv);
+};
+
+static int imx_ocotp_wait_for_busy(void __iomem *base, u32 flags)
+{
+	int count;
+	u32 c, mask;
+
+	mask = IMX_OCOTP_BM_CTRL_BUSY | IMX_OCOTP_BM_CTRL_ERROR | flags;
+
+	for (count = 10000; count >= 0; count--) {
+		c = readl(base + IMX_OCOTP_ADDR_CTRL);
+		if (!(c & mask))
+			break;
+		cpu_relax();
+	}
+
+	if (count < 0) {
+		/* HW_OCOTP_CTRL[ERROR] will be set under the following
+		 * conditions:
+		 * - A write is performed to a shadow register during a shadow
+		 *   reload (essentially, while HW_OCOTP_CTRL[RELOAD_SHADOWS] is
+		 *   set. In addition, the contents of the shadow register shall
+		 *   not be updated.
+		 * - A write is performed to a shadow register which has been
+		 *   locked.
+		 * - A read is performed to from a shadow register which has
+		 *   been read locked.
+		 * - A program is performed to a fuse word which has been locked
+		 * - A read is performed to from a fuse word which has been read
+		 *   locked.
+		 */
+		if (c & IMX_OCOTP_BM_CTRL_ERROR)
+			return -EPERM;
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static void imx_ocotp_clr_err_if_set(void __iomem *base)
+{
+	u32 c;
+
+	c = readl(base + IMX_OCOTP_ADDR_CTRL);
+	if (!(c & IMX_OCOTP_BM_CTRL_ERROR))
+		return;
+
+	writel(IMX_OCOTP_BM_CTRL_ERROR, base + IMX_OCOTP_ADDR_CTRL_CLR);
+}
+
+static int imx_ocotp_read(void *context, unsigned int offset,
+			  void *val, size_t bytes)
+{
+	struct ocotp_priv *priv = context;
+	unsigned int count;
+	u32 *buf = val;
+	int i, ret;
+	u32 index;
+
+	index = offset >> 2;
+	count = bytes >> 2;
+
+	if (count > (priv->params->nregs - index))
+		count = priv->params->nregs - index;
+
+	mutex_lock(&ocotp_mutex);
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret < 0) {
+		mutex_unlock(&ocotp_mutex);
+		dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
+		return ret;
+	}
+
+	ret = imx_ocotp_wait_for_busy(priv->base, 0);
+	if (ret < 0) {
+		dev_err(priv->dev, "timeout during read setup\n");
+		goto read_end;
+	}
+
+	for (i = index; i < (index + count); i++) {
+		*buf++ = readl(priv->base + IMX_OCOTP_OFFSET_B0W0 +
+			       i * IMX_OCOTP_OFFSET_PER_WORD);
+
+		/* 47.3.1.2
+		 * For "read locked" registers 0xBADABADA will be returned and
+		 * HW_OCOTP_CTRL[ERROR] will be set. It must be cleared by
+		 * software before any new write, read or reload access can be
+		 * issued
+		 */
+		if (*(buf - 1) == IMX_OCOTP_READ_LOCKED_VAL)
+			imx_ocotp_clr_err_if_set(priv->base);
+	}
+	ret = 0;
+
+read_end:
+	clk_disable_unprepare(priv->clk);
+	mutex_unlock(&ocotp_mutex);
+	return ret;
+}
+
+static void imx_ocotp_set_imx6_timing(struct ocotp_priv *priv)
+{
+	unsigned long clk_rate = 0;
+	unsigned long strobe_read, relax, strobe_prog;
+	u32 timing = 0;
+
+	/* 47.3.1.3.1
+	 * Program HW_OCOTP_TIMING[STROBE_PROG] and HW_OCOTP_TIMING[RELAX]
+	 * fields with timing values to match the current frequency of the
+	 * ipg_clk. OTP writes will work at maximum bus frequencies as long
+	 * as the HW_OCOTP_TIMING parameters are set correctly.
+	 *
+	 * Note: there are minimum timings required to ensure an OTP fuse burns
+	 * correctly that are independent of the ipg_clk. Those values are not
+	 * formally documented anywhere however, working from the minimum
+	 * timings given in u-boot we can say:
+	 *
+	 * - Minimum STROBE_PROG time is 10 microseconds. Intuitively 10
+	 *   microseconds feels about right as representative of a minimum time
+	 *   to physically burn out a fuse.
+	 *
+	 * - Minimum STROBE_READ i.e. the time to wait post OTP fuse burn before
+	 *   performing another read is 37 nanoseconds
+	 *
+	 * - Minimum RELAX timing is 17 nanoseconds. This final RELAX minimum
+	 *   timing is not entirely clear the documentation says "This
+	 *   count value specifies the time to add to all default timing
+	 *   parameters other than the Tpgm and Trd. It is given in number
+	 *   of ipg_clk periods." where Tpgm and Trd refer to STROBE_PROG
+	 *   and STROBE_READ respectively. What the other timing parameters
+	 *   are though, is not specified. Experience shows a zero RELAX
+	 *   value will mess up a re-load of the shadow registers post OTP
+	 *   burn.
+	 */
+	clk_rate = clk_get_rate(priv->clk);
+
+	relax = DIV_ROUND_UP(clk_rate * TIMING_RELAX_NS, 1000000000) - 1;
+	strobe_read = DIV_ROUND_UP(clk_rate * TIMING_STROBE_READ_NS,
+				   1000000000);
+	strobe_read += 2 * (relax + 1) - 1;
+	strobe_prog = DIV_ROUND_CLOSEST(clk_rate * TIMING_STROBE_PROG_US,
+					1000000);
+	strobe_prog += 2 * (relax + 1) - 1;
+
+	timing = readl(priv->base + IMX_OCOTP_ADDR_TIMING) & 0x0FC00000;
+	timing |= strobe_prog & 0x00000FFF;
+	timing |= (relax       << 12) & 0x0000F000;
+	timing |= (strobe_read << 16) & 0x003F0000;
+
+	writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
+}
+
+static void imx_ocotp_set_imx7_timing(struct ocotp_priv *priv)
+{
+	unsigned long clk_rate = 0;
+	u64 fsource, strobe_prog;
+	u32 timing = 0;
+
+	/* i.MX 7Solo Applications Processor Reference Manual, Rev. 0.1
+	 * 6.4.3.3
+	 */
+	clk_rate = clk_get_rate(priv->clk);
+	fsource = DIV_ROUND_UP_ULL((u64)clk_rate * DEF_FSOURCE,
+				   NSEC_PER_SEC) + 1;
+	strobe_prog = DIV_ROUND_CLOSEST_ULL((u64)clk_rate * DEF_STROBE_PROG,
+					    NSEC_PER_SEC) + 1;
+
+	timing = strobe_prog & 0x00000FFF;
+	timing |= (fsource << 12) & 0x000FF000;
+
+	writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
+}
+
+static int imx_ocotp_write(void *context, unsigned int offset, void *val,
+			   size_t bytes)
+{
+	struct ocotp_priv *priv = context;
+	u32 *buf = val;
+	int ret;
+
+	u32 ctrl;
+	u8 waddr;
+	u8 word = 0;
+
+	/* allow only writing one complete OTP word at a time */
+	if ((bytes != priv->config->word_size) ||
+	    (offset % priv->config->word_size))
+		return -EINVAL;
+
+	mutex_lock(&ocotp_mutex);
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret < 0) {
+		mutex_unlock(&ocotp_mutex);
+		dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
+		return ret;
+	}
+
+	/* Setup the write timing values */
+	priv->params->set_timing(priv);
+
+	/* 47.3.1.3.2
+	 * Check that HW_OCOTP_CTRL[BUSY] and HW_OCOTP_CTRL[ERROR] are clear.
+	 * Overlapped accesses are not supported by the controller. Any pending
+	 * write or reload must be completed before a write access can be
+	 * requested.
+	 */
+	ret = imx_ocotp_wait_for_busy(priv->base, 0);
+	if (ret < 0) {
+		dev_err(priv->dev, "timeout during timing setup\n");
+		goto write_end;
+	}
+
+	/* 47.3.1.3.3
+	 * Write the requested address to HW_OCOTP_CTRL[ADDR] and program the
+	 * unlock code into HW_OCOTP_CTRL[WR_UNLOCK]. This must be programmed
+	 * for each write access. The lock code is documented in the register
+	 * description. Both the unlock code and address can be written in the
+	 * same operation.
+	 */
+	if (priv->params->bank_address_words != 0) {
+		/*
+		 * In banked/i.MX7 mode the OTP register bank goes into waddr
+		 * see i.MX 7Solo Applications Processor Reference Manual, Rev.
+		 * 0.1 section 6.4.3.1
+		 */
+		offset = offset / priv->config->word_size;
+		waddr = offset / priv->params->bank_address_words;
+		word  = offset & (priv->params->bank_address_words - 1);
+	} else {
+		/*
+		 * Non-banked i.MX6 mode.
+		 * OTP write/read address specifies one of 128 word address
+		 * locations
+		 */
+		waddr = offset / 4;
+	}
+
+	ctrl = readl(priv->base + IMX_OCOTP_ADDR_CTRL);
+	ctrl &= ~IMX_OCOTP_BM_CTRL_ADDR;
+	ctrl |= waddr & IMX_OCOTP_BM_CTRL_ADDR;
+	ctrl |= IMX_OCOTP_WR_UNLOCK;
+
+	writel(ctrl, priv->base + IMX_OCOTP_ADDR_CTRL);
+
+	/* 47.3.1.3.4
+	 * Write the data to the HW_OCOTP_DATA register. This will automatically
+	 * set HW_OCOTP_CTRL[BUSY] and clear HW_OCOTP_CTRL[WR_UNLOCK]. To
+	 * protect programming same OTP bit twice, before program OCOTP will
+	 * automatically read fuse value in OTP and use read value to mask
+	 * program data. The controller will use masked program data to program
+	 * a 32-bit word in the OTP per the address in HW_OCOTP_CTRL[ADDR]. Bit
+	 * fields with 1's will result in that OTP bit being programmed. Bit
+	 * fields with 0's will be ignored. At the same time that the write is
+	 * accepted, the controller makes an internal copy of
+	 * HW_OCOTP_CTRL[ADDR] which cannot be updated until the next write
+	 * sequence is initiated. This copy guarantees that erroneous writes to
+	 * HW_OCOTP_CTRL[ADDR] will not affect an active write operation. It
+	 * should also be noted that during the programming HW_OCOTP_DATA will
+	 * shift right (with zero fill). This shifting is required to program
+	 * the OTP serially. During the write operation, HW_OCOTP_DATA cannot be
+	 * modified.
+	 * Note: on i.MX7 there are four data fields to write for banked write
+	 *       with the fuse blowing operation only taking place after data0
+	 *	 has been written. This is why data0 must always be the last
+	 *	 register written.
+	 */
+	if (priv->params->bank_address_words != 0) {
+		/* Banked/i.MX7 mode */
+		switch (word) {
+		case 0:
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
+			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
+			break;
+		case 1:
+			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA1);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
+			break;
+		case 2:
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
+			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA2);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
+			break;
+		case 3:
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
+			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA3);
+			writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
+			break;
+		}
+	} else {
+		/* Non-banked i.MX6 mode */
+		writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
+	}
+
+	/* 47.4.1.4.5
+	 * Once complete, the controller will clear BUSY. A write request to a
+	 * protected or locked region will result in no OTP access and no
+	 * setting of HW_OCOTP_CTRL[BUSY]. In addition HW_OCOTP_CTRL[ERROR] will
+	 * be set. It must be cleared by software before any new write access
+	 * can be issued.
+	 */
+	ret = imx_ocotp_wait_for_busy(priv->base, 0);
+	if (ret < 0) {
+		if (ret == -EPERM) {
+			dev_err(priv->dev, "failed write to locked region");
+			imx_ocotp_clr_err_if_set(priv->base);
+		} else {
+			dev_err(priv->dev, "timeout during data write\n");
+		}
+		goto write_end;
+	}
+
+	/* 47.3.1.4
+	 * Write Postamble: Due to internal electrical characteristics of the
+	 * OTP during writes, all OTP operations following a write must be
+	 * separated by 2 us after the clearing of HW_OCOTP_CTRL_BUSY following
+	 * the write.
+	 */
+	udelay(2);
+
+	/* reload all shadow registers */
+	writel(IMX_OCOTP_BM_CTRL_REL_SHADOWS,
+	       priv->base + IMX_OCOTP_ADDR_CTRL_SET);
+	ret = imx_ocotp_wait_for_busy(priv->base,
+				      IMX_OCOTP_BM_CTRL_REL_SHADOWS);
+	if (ret < 0) {
+		dev_err(priv->dev, "timeout during shadow register reload\n");
+		goto write_end;
+	}
+
+write_end:
+	clk_disable_unprepare(priv->clk);
+	mutex_unlock(&ocotp_mutex);
+	if (ret < 0)
+		return ret;
+	return bytes;
+}
+
+static struct nvmem_config imx_ocotp_nvmem_config = {
+	.name = "imx-ocotp",
+	.read_only = false,
+	.word_size = 4,
+	.stride = 4,
+	.reg_read = imx_ocotp_read,
+	.reg_write = imx_ocotp_write,
+};
+
+static const struct ocotp_params imx6q_params = {
+	.nregs = 128,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx6sl_params = {
+	.nregs = 64,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx6sll_params = {
+	.nregs = 80,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx6sx_params = {
+	.nregs = 128,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx6ul_params = {
+	.nregs = 144,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx6ull_params = {
+	.nregs = 80,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx7d_params = {
+	.nregs = 64,
+	.bank_address_words = 4,
+	.set_timing = imx_ocotp_set_imx7_timing,
+};
+
+static const struct ocotp_params imx7ulp_params = {
+	.nregs = 256,
+	.bank_address_words = 0,
+};
+
+static const struct ocotp_params imx8mq_params = {
+	.nregs = 256,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx8mm_params = {
+	.nregs = 256,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct ocotp_params imx8mn_params = {
+	.nregs = 256,
+	.bank_address_words = 0,
+	.set_timing = imx_ocotp_set_imx6_timing,
+};
+
+static const struct of_device_id imx_ocotp_dt_ids[] = {
+	{ .compatible = "fsl,imx6q-ocotp",  .data = &imx6q_params },
+	{ .compatible = "fsl,imx6sl-ocotp", .data = &imx6sl_params },
+	{ .compatible = "fsl,imx6sx-ocotp", .data = &imx6sx_params },
+	{ .compatible = "fsl,imx6ul-ocotp", .data = &imx6ul_params },
+	{ .compatible = "fsl,imx6ull-ocotp", .data = &imx6ull_params },
+	{ .compatible = "fsl,imx7d-ocotp",  .data = &imx7d_params },
+	{ .compatible = "fsl,imx6sll-ocotp", .data = &imx6sll_params },
+	{ .compatible = "fsl,imx7ulp-ocotp", .data = &imx7ulp_params },
+	{ .compatible = "fsl,imx8mq-ocotp", .data = &imx8mq_params },
+	{ .compatible = "fsl,imx8mm-ocotp", .data = &imx8mm_params },
+	{ .compatible = "fsl,imx8mn-ocotp", .data = &imx8mn_params },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, imx_ocotp_dt_ids);
+
+static int imx_ocotp_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ocotp_priv *priv;
+	struct nvmem_device *nvmem;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+
+	priv->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->clk))
+		return PTR_ERR(priv->clk);
+
+	clk_prepare_enable(priv->clk);
+	imx_ocotp_clr_err_if_set(priv->base);
+	clk_disable_unprepare(priv->clk);
+
+	priv->params = of_device_get_match_data(&pdev->dev);
+	imx_ocotp_nvmem_config.size = 4 * priv->params->nregs;
+	imx_ocotp_nvmem_config.dev = dev;
+	imx_ocotp_nvmem_config.priv = priv;
+	priv->config = &imx_ocotp_nvmem_config;
+	nvmem = devm_nvmem_register(dev, &imx_ocotp_nvmem_config);
+
+
+	return PTR_ERR_OR_ZERO(nvmem);
+}
+
+static struct platform_driver imx_ocotp_driver = {
+	.probe	= imx_ocotp_probe,
+	.driver = {
+		.name	= "imx_ocotp",
+		.of_match_table = imx_ocotp_dt_ids,
+	},
+};
+module_platform_driver(imx_ocotp_driver);
+
+MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
+MODULE_DESCRIPTION("i.MX6/i.MX7 OCOTP fuse box driver");
+MODULE_LICENSE("GPL v2");