misc: add driver for the Rockchip otp controller

Newer Rockchip socs like the px30 use a different ip block to handle
one-time-programmable memory, so add a misc driver for it as well.

Signed-off-by: Finley Xiao <finley.xiao@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

drivers/misc/Kconfig

@@ -59,6 +59,15 @@ config ROCKCHIP_EFUSE
 	  extended (by porting the read function from the Linux kernel sources)
 	  to support other recent Rockchip devices.
 
+config ROCKCHIP_OTP
+	bool "Rockchip OTP Support"
+	depends on MISC
+	help
+	  Enable (read-only) access for the one-time-programmable memory block
+	  found in Rockchip SoCs: accesses can either be made using byte
+	  addressing and a length or through child-nodes that are generated
+	  based on the e-fuse map retrieved from the DTS.
+
 config VEXPRESS_CONFIG
 	bool "Enable support for Arm Versatile Express config bus"
 	depends on MISC

drivers/misc/Makefile

@@ -53,6 +53,7 @@ obj-$(CONFIG_PCA9551_LED) += pca9551_led.o
 obj-$(CONFIG_$(SPL_)PWRSEQ) += pwrseq-uclass.o
 obj-$(CONFIG_QFW) += qfw.o
 obj-$(CONFIG_ROCKCHIP_EFUSE) += rockchip-efuse.o
+obj-$(CONFIG_ROCKCHIP_OTP) += rockchip-otp.o
 obj-$(CONFIG_SANDBOX) += syscon_sandbox.o misc_sandbox.o
 obj-$(CONFIG_SMSC_LPC47M) += smsc_lpc47m.o
 obj-$(CONFIG_SMSC_SIO1007) += smsc_sio1007.o

drivers/misc/rockchip-otp.c

@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Fuzhou Rockchip Electronics Co., Ltd
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <command.h>
+#include <dm.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <misc.h>
+
+/* OTP Register Offsets */
+#define OTPC_SBPI_CTRL			0x0020
+#define OTPC_SBPI_CMD_VALID_PRE		0x0024
+#define OTPC_SBPI_CS_VALID_PRE		0x0028
+#define OTPC_SBPI_STATUS		0x002C
+#define OTPC_USER_CTRL			0x0100
+#define OTPC_USER_ADDR			0x0104
+#define OTPC_USER_ENABLE		0x0108
+#define OTPC_USER_QP			0x0120
+#define OTPC_USER_Q			0x0124
+#define OTPC_INT_STATUS			0x0304
+#define OTPC_SBPI_CMD0_OFFSET		0x1000
+#define OTPC_SBPI_CMD1_OFFSET		0x1004
+
+/* OTP Register bits and masks */
+#define OTPC_USER_ADDR_MASK		GENMASK(31, 16)
+#define OTPC_USE_USER			BIT(0)
+#define OTPC_USE_USER_MASK		GENMASK(16, 16)
+#define OTPC_USER_FSM_ENABLE		BIT(0)
+#define OTPC_USER_FSM_ENABLE_MASK	GENMASK(16, 16)
+#define OTPC_SBPI_DONE			BIT(1)
+#define OTPC_USER_DONE			BIT(2)
+
+#define SBPI_DAP_ADDR			0x02
+#define SBPI_DAP_ADDR_SHIFT		8
+#define SBPI_DAP_ADDR_MASK		GENMASK(31, 24)
+#define SBPI_CMD_VALID_MASK		GENMASK(31, 16)
+#define SBPI_DAP_CMD_WRF		0xC0
+#define SBPI_DAP_REG_ECC		0x3A
+#define SBPI_ECC_ENABLE			0x00
+#define SBPI_ECC_DISABLE		0x09
+#define SBPI_ENABLE			BIT(0)
+#define SBPI_ENABLE_MASK		GENMASK(16, 16)
+
+#define OTPC_TIMEOUT			10000
+
+struct rockchip_otp_platdata {
+	void __iomem *base;
+	unsigned long secure_conf_base;
+	unsigned long otp_mask_base;
+};
+
+static int rockchip_otp_wait_status(struct rockchip_otp_platdata *otp,
+				    u32 flag)
+{
+	int delay = OTPC_TIMEOUT;
+
+	while (!(readl(otp->base + OTPC_INT_STATUS) & flag)) {
+		udelay(1);
+		delay--;
+		if (delay <= 0) {
+			printf("%s: wait init status timeout\n", __func__);
+			return -ETIMEDOUT;
+		}
+	}
+
+	/* clean int status */
+	writel(flag, otp->base + OTPC_INT_STATUS);
+
+	return 0;
+}
+
+static int rockchip_otp_ecc_enable(struct rockchip_otp_platdata *otp,
+				   bool enable)
+{
+	int ret = 0;
+
+	writel(SBPI_DAP_ADDR_MASK | (SBPI_DAP_ADDR << SBPI_DAP_ADDR_SHIFT),
+	       otp->base + OTPC_SBPI_CTRL);
+
+	writel(SBPI_CMD_VALID_MASK | 0x1, otp->base + OTPC_SBPI_CMD_VALID_PRE);
+	writel(SBPI_DAP_CMD_WRF | SBPI_DAP_REG_ECC,
+	       otp->base + OTPC_SBPI_CMD0_OFFSET);
+
+	if (enable)
+		writel(SBPI_ECC_ENABLE, otp->base + OTPC_SBPI_CMD1_OFFSET);
+	else
+		writel(SBPI_ECC_DISABLE, otp->base + OTPC_SBPI_CMD1_OFFSET);
+
+	writel(SBPI_ENABLE_MASK | SBPI_ENABLE, otp->base + OTPC_SBPI_CTRL);
+
+	ret = rockchip_otp_wait_status(otp, OTPC_SBPI_DONE);
+	if (ret < 0)
+		printf("%s timeout during ecc_enable\n", __func__);
+
+	return ret;
+}
+
+static int rockchip_px30_otp_read(struct udevice *dev, int offset,
+				  void *buf, int size)
+{
+	struct rockchip_otp_platdata *otp = dev_get_platdata(dev);
+	u8 *buffer = buf;
+	int ret = 0;
+
+	ret = rockchip_otp_ecc_enable(otp, false);
+	if (ret < 0) {
+		printf("%s rockchip_otp_ecc_enable err\n", __func__);
+		return ret;
+	}
+
+	writel(OTPC_USE_USER | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL);
+	udelay(5);
+	while (size--) {
+		writel(offset++ | OTPC_USER_ADDR_MASK,
+		       otp->base + OTPC_USER_ADDR);
+		writel(OTPC_USER_FSM_ENABLE | OTPC_USER_FSM_ENABLE_MASK,
+		       otp->base + OTPC_USER_ENABLE);
+
+		ret = rockchip_otp_wait_status(otp, OTPC_USER_DONE);
+		if (ret < 0) {
+			printf("%s timeout during read setup\n", __func__);
+			goto read_end;
+		}
+
+		*buffer++ = readb(otp->base + OTPC_USER_Q);
+	}
+
+read_end:
+	writel(0x0 | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL);
+
+	return ret;
+}
+
+static int rockchip_otp_read(struct udevice *dev, int offset,
+			     void *buf, int size)
+{
+	return rockchip_px30_otp_read(dev, offset, buf, size);
+}
+
+static const struct misc_ops rockchip_otp_ops = {
+	.read = rockchip_otp_read,
+};
+
+static int rockchip_otp_ofdata_to_platdata(struct udevice *dev)
+{
+	struct rockchip_otp_platdata *otp = dev_get_platdata(dev);
+
+	otp->base = dev_read_addr_ptr(dev);
+
+	return 0;
+}
+
+static const struct udevice_id rockchip_otp_ids[] = {
+	{
+		.compatible = "rockchip,px30-otp",
+		.data = (ulong)&rockchip_px30_otp_read,
+	},
+	{
+		.compatible = "rockchip,rk3308-otp",
+		.data = (ulong)&rockchip_px30_otp_read,
+	},
+	{}
+};
+
+U_BOOT_DRIVER(rockchip_otp) = {
+	.name = "rockchip_otp",
+	.id = UCLASS_MISC,
+	.of_match = rockchip_otp_ids,
+	.ops = &rockchip_otp_ops,
+	.ofdata_to_platdata = rockchip_otp_ofdata_to_platdata,
+	.platdata_auto_alloc_size = sizeof(struct rockchip_otp_platdata),
+};