MLK-12483-3 mx6: Add a module fuse checking

Implement a functionality to read the soc fuses and check if any module
is fused. For fused module, we have to disable it in u-boot dynamically,
and change the its node in FDT to "disabled" status before starting the kernel.

In this patch, we implement the ft_system_setup for FDT fixup. This function will
be called during boot process or by "fdt systemsetup" command.

To enable the module fuse checking, two configurations must be defined:
CONFIG_MODULE_FUSE
CONFIG_OF_SYSTEM_SETUP

Signed-off-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit 7236051526b73a5a25cc8330a79f5c08b7d70726)

3 files changed, 278 insertions, 1 deletions

diff --git a/arch/arm/cpu/armv7/mx6/Kconfig b/arch/arm/cpu/armv7/mx6/Kconfig
index b679d0f..d34a7cd 100644
--- a/arch/arm/cpu/armv7/mx6/Kconfig
+++ b/arch/arm/cpu/armv7/mx6/Kconfig
@@ -60,6 +60,14 @@ config CMD_BEE
 	help
 	  Set "Y" to enable the bee commands 
 
+config MODULE_FUSE
+	bool "Enable the module disable fuse checking on i.MX6"
+	default n
+	select OF_SYSTEM_SETUP
+	help
+	  Once the module is checked as fused to disable, this module driver
+	  won't be called. And it will be modified to disable in kernel DTB.
+
 choice
 	prompt "MX6 board select"
 	optional
diff --git a/arch/arm/cpu/armv7/mx6/Makefile b/arch/arm/cpu/armv7/mx6/Makefile
index d240f3a..7194bb6 100644
--- a/arch/arm/cpu/armv7/mx6/Makefile
+++ b/arch/arm/cpu/armv7/mx6/Makefile
@@ -2,7 +2,7 @@
 # (C) Copyright 2000-2006
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 #
-# (C) Copyright 2011-2015 Freescale Semiconductor, Inc.
+# (C) Copyright 2011-2016 Freescale Semiconductor, Inc.
 #
 # SPDX-License-Identifier:	GPL-2.0+
 #
@@ -14,3 +14,4 @@ obj-$(CONFIG_MX6UL_LITESOM)  += litesom.o
 ifdef CONFIG_MX6UL
 obj-$(CONFIG_CMD_BEE)        += bee.o
 endif
+obj-$(CONFIG_MODULE_FUSE)        += module_fuse.o
diff --git a/arch/arm/cpu/armv7/mx6/module_fuse.c b/arch/arm/cpu/armv7/mx6/module_fuse.c
new file mode 100644
index 0000000..a4164f5
--- /dev/null
+++ b/arch/arm/cpu/armv7/mx6/module_fuse.c
@@ -0,0 +1,268 @@
+/*
+ * (C) Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <fdt_support.h>
+#include <asm/io.h>
+#include <linux/errno.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/module_fuse.h>
+
+struct fuse_entry_desc {
+	enum fuse_module_type module;
+	const char *node_path;
+	u32 fuse_word_offset;
+	u32 fuse_bit_offset;
+	u32 status;
+};
+
+static struct fuse_entry_desc mx6_fuse_descs[] = {
+#ifdef CONFIG_MX6UL
+	{MX6_MODULE_TSC, "/soc/aips-bus@02000000/tsc@02040000", 0x430, 22},
+	{MX6_MODULE_ADC2, "/soc/aips-bus@02100000/adc@0219c000", 0x430, 23},
+	{MX6_MODULE_SIM1, "/soc/aips-bus@02100000/sim@0218c000", 0x430, 24},
+	{MX6_MODULE_SIM2, "/soc/aips-bus@02100000/sim@021b4000", 0x430, 25},
+	{MX6_MODULE_FLEXCAN1, "/soc/aips-bus@02000000/can@02090000", 0x430, 26},
+	{MX6_MODULE_FLEXCAN2, "/soc/aips-bus@02000000/can@02094000", 0x430, 27},
+	{MX6_MODULE_SPDIF, "/soc/aips-bus@02000000/spba-bus@02000000/spdif@02004000", 0x440, 2},
+	{MX6_MODULE_EIM, "/soc/aips-bus@02100000/weim@021b8000", 0x440, 3},
+	{MX6_MODULE_SD1, "/soc/aips-bus@02100000/usdhc@02190000", 0x440, 4},
+	{MX6_MODULE_SD2, "/soc/aips-bus@02100000/usdhc@02194000", 0x440, 5},
+	{MX6_MODULE_QSPI1, "/soc/aips-bus@02100000/qspi@021e0000", 0x440, 6},
+	{MX6_MODULE_GPMI, "/soc/gpmi-nand@01806000", 0x440, 7},
+	{MX6_MODULE_APBHDMA, "/soc/dma-apbh@01804000", 0x440, 7},
+	{MX6_MODULE_LCDIF, "/soc/aips-bus@02100000/lcdif@021c8000", 0x440, 8},
+	{MX6_MODULE_PXP, "/soc/aips-bus@02100000/pxp@021cc000", 0x440, 9},
+	{MX6_MODULE_CSI, "/soc/aips-bus@02100000/csi@021c4000", 0x440, 10},
+	{MX6_MODULE_ADC1, "/soc/aips-bus@02100000/adc@02198000", 0x440, 11},
+	{MX6_MODULE_ENET1, "/soc/aips-bus@02100000/ethernet@02188000", 0x440, 12},
+	{MX6_MODULE_ENET2, "/soc/aips-bus@02000000/ethernet@020b4000", 0x440, 13},
+	{MX6_MODULE_CAAM, "/soc/aips-bus@02100000/caam@2140000", 0x440, 14},
+	{MX6_MODULE_USB_OTG2, "/soc/aips-bus@02100000/usb@02184200", 0x440, 15},
+	{MX6_MODULE_SAI2, "/soc/aips-bus@02000000/spba-bus@02000000/sai@0202c000", 0x440, 24},
+	{MX6_MODULE_SAI3, "/soc/aips-bus@02000000/spba-bus@02000000/sai@02030000", 0x440, 24},
+	{MX6_MODULE_BEE, "/soc/aips-bus@02000000/bee@02044000", 0x440, 25},
+	{MX6_MODULE_UART5, "/soc/aips-bus@02100000/serial@021f4000", 0x440, 26},
+	{MX6_MODULE_UART6, "/soc/aips-bus@02100000/serial@021fc000", 0x440, 26},
+	{MX6_MODULE_UART7, "/soc/aips-bus@02000000/spba-bus@02000000/serial@02018000", 0x440, 26},
+	{MX6_MODULE_UART8, "/soc/aips-bus@02000000/spba-bus@02000000/serial@02024000", 0x440, 26},
+	{MX6_MODULE_PWM5, "/soc/aips-bus@02000000/pwm@020f0000", 0x440, 27},
+	{MX6_MODULE_PWM6, "/soc/aips-bus@02000000/pwm@020f4000", 0x440, 27},
+	{MX6_MODULE_PWM7, "/soc/aips-bus@02000000/pwm@020f8000", 0x440, 27},
+	{MX6_MODULE_PWM8, "/soc/aips-bus@02000000/pwm@020fc000", 0x440, 27},
+	{MX6_MODULE_ECSPI3, "/soc/aips-bus@02000000/spba-bus@02000000/ecspi@02010000", 0x440, 28},
+	{MX6_MODULE_ECSPI4, "/soc/aips-bus@02000000/spba-bus@02000000/ecspi@02014000", 0x440, 28},
+	{MX6_MODULE_I2C3, "/soc/aips-bus@02100000/i2c@021a8000", 0x440, 29},
+	{MX6_MODULE_I2C4, "/soc/aips-bus@02100000/i2c@021f8000", 0x440, 29},
+	{MX6_MODULE_GPT2, "/soc/aips-bus@02000000/gpt@020e8000", 0x440, 30},
+	{MX6_MODULE_EPIT2, "/soc/aips-bus@02000000/epit@020d4000", 0x440, 31},
+#endif
+};
+
+u32 check_module_fused(enum fuse_module_type module)
+{
+	u32 i, reg;
+	for (i = 0; i < ARRAY_SIZE(mx6_fuse_descs); i++) {
+		if (mx6_fuse_descs[i].module == module) {
+			reg = readl(OCOTP_BASE_ADDR + mx6_fuse_descs[i].fuse_word_offset);
+			if (reg & (1 << mx6_fuse_descs[i].fuse_bit_offset))
+				return 1; /* disabled */
+			else
+				return 0; /* enabled */
+		}
+	}
+
+	return  0; /* Not has a fuse, always enabled */
+}
+
+#ifdef DEBUG
+void print_fuse_status()
+{
+	u32 i, reg;
+
+	for (i = 0; i < ARRAY_SIZE(mx6_fuse_descs); i++) {
+		reg = readl(OCOTP_BASE_ADDR + mx6_fuse_descs[i].fuse_word_offset);
+		if (reg & (1 << mx6_fuse_descs[i].fuse_bit_offset))
+			printf("%s, disabled\n", mx6_fuse_descs[i].node_path);
+	}
+}
+
+void simulate_fuse()
+{
+	u32 i, reg;
+
+    for (i = 0; i < ARRAY_SIZE(mx6_fuse_descs); i++) {
+		if (MX6_MODULE_SD2 == mx6_fuse_descs[i].module)
+			continue;
+
+		reg = readl(OCOTP_BASE_ADDR + mx6_fuse_descs[i].fuse_word_offset);
+		reg |= (1 << mx6_fuse_descs[i].fuse_bit_offset);
+		writel(reg, OCOTP_BASE_ADDR + mx6_fuse_descs[i].fuse_word_offset);
+    }
+}
+#endif
+
+#ifdef CONFIG_OF_SYSTEM_SETUP
+int ft_system_setup(void *blob, bd_t *bd)
+{
+	u32 i, reg;
+	const char *status = "disabled";
+	int rc;
+
+	for (i = 0; i < ARRAY_SIZE(mx6_fuse_descs); i++) {
+		reg = readl(OCOTP_BASE_ADDR + mx6_fuse_descs[i].fuse_word_offset);
+		if (reg & (1 << mx6_fuse_descs[i].fuse_bit_offset)) {
+
+			int nodeoff = fdt_path_offset(blob, mx6_fuse_descs[i].node_path);
+			if (nodeoff < 0)
+				continue; /* Not found, skip it */
+add_status:
+			rc = fdt_setprop(blob, nodeoff, "status", status, strlen(status) + 1);
+			if (rc) {
+				if (rc == -FDT_ERR_NOSPACE) {
+					rc = fdt_increase_size(blob, 512);
+					if (!rc)
+						goto add_status;
+				}
+				printf("Unable to update property %s:%s, err=%s\n",
+					mx6_fuse_descs[i].node_path, "status", fdt_strerror(rc));
+			} else {
+				printf("Modify %s:%s disabled\n",
+					mx6_fuse_descs[i].node_path, "status");
+			}
+		}
+	}
+
+	printf("ft_system_setup for mx6\n");
+
+	return 0;
+}
+#endif
+
+u32 mx6_esdhc_fused(u32 base_addr)
+{
+	switch (base_addr) {
+	case USDHC1_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_SD1);
+	case USDHC2_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_SD2);
+#ifdef USDHC3_BASE_ADDR
+	case USDHC3_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_SD3);
+#endif
+#ifdef USDHC4_BASE_ADDR
+	case USDHC4_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_SD4);
+#endif
+	default:
+		return 0;
+	}
+}
+
+u32 mx6_ecspi_fused(u32 base_addr)
+{
+	switch (base_addr) {
+	case ECSPI1_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ECSPI1);
+	case ECSPI2_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ECSPI2);
+	case ECSPI3_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ECSPI3);
+	case ECSPI4_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ECSPI4);
+#ifdef ECSPI5_BASE_ADDR
+	case ECSPI5_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ECSPI5);
+#endif
+	default:
+		return 0;
+	}
+}
+
+u32 mx6_uart_fused(u32 base_addr)
+{
+	switch (base_addr) {
+	case UART1_BASE:
+		return check_module_fused(MX6_MODULE_UART1);
+	case UART2_BASE:
+		return check_module_fused(MX6_MODULE_UART2);
+	case UART3_BASE:
+		return check_module_fused(MX6_MODULE_UART3);
+	case UART4_BASE:
+		return check_module_fused(MX6_MODULE_UART4);
+	case UART5_BASE:
+		return check_module_fused(MX6_MODULE_UART5);
+	case MX6UL_UART6_BASE_ADDR:
+	case MX6SX_UART6_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_UART6);
+#ifdef UART7_IPS_BASE_ADDR
+	case UART7_IPS_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_UART7);
+#endif
+#ifdef UART8_IPS_BASE_ADDR
+	case UART8_IPS_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_UART8);
+#endif
+	}
+
+	return 0;
+}
+
+u32 mx6_usb_fused(u32 base_addr)
+{
+	int i = (base_addr - USB_BASE_ADDR) / 0x200;
+	return check_module_fused(MX6_MODULE_USB_OTG1 + i);
+}
+
+u32 mx6_qspi_fused(u32 base_addr)
+{
+	switch (base_addr) {
+#ifdef QSPI1_BASE_ADDR
+	case QSPI1_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_QSPI1);
+#endif
+
+#ifdef QSPI2_BASE_ADDR
+	case QSPI2_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_QSPI2);
+#endif
+	default:
+		return 0;
+	}
+}
+
+u32 mx6_i2c_fused(u32 base_addr)
+{
+	switch (base_addr) {
+	case I2C1_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_I2C1);
+	case I2C2_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_I2C2);
+	case I2C3_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_I2C3);
+#ifdef I2C4_BASE_ADDR
+	case I2C4_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_I2C4);
+#endif
+	}
+
+	return 0;
+}
+
+u32 mx6_enet_fused(u32 base_addr)
+{
+	switch (base_addr) {
+	case ENET_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ENET1);
+#ifdef ENET2_BASE_ADDR
+	case ENET2_BASE_ADDR:
+		return check_module_fused(MX6_MODULE_ENET2);
+#endif
+	default:
+		return 0;
+	}
+}