arm: mvebu: system-controller: Add support for SYSRESET

Add driver model support for sysreset via mvebu system controller. This is
currently only available for U-Boot proper.

Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>

arch/arm/mach-mvebu/Kconfig

@@ -19,6 +19,7 @@ config ARMADA_32BIT
 	select SPL_SYS_NO_VECTOR_TABLE if SPL
 	select ARCH_VERY_EARLY_INIT
 	select ARMADA_32BIT_SYSCON_RESET if DM_RESET && PCI_MVEBU
+	select ARMADA_32BIT_SYSCON_SYSRESET if SYSRESET
 
 # ARMv7 SoCs...
 config ARMADA_375
@@ -457,16 +458,29 @@ config SF_DEFAULT_MODE
 	default 0x0
 	depends on MVEBU_SPL_BOOT_DEVICE_SPI
 
+config ARMADA_32BIT_SYSCON
+	bool
+	depends on ARMADA_32BIT
+	select REGMAP
+	select SYSCON
+
 config ARMADA_32BIT_SYSCON_RESET
 	bool "Support Armada XP/375/38x/39x reset controller"
 	depends on ARMADA_32BIT
 	depends on DM_RESET
-	select REGMAP
-	select SYSCON
+	select ARMADA_32BIT_SYSCON
 	help
 	  Build support for Armada XP/375/38x/39x reset controller. This is
 	  needed for PCIe support.
 
+config ARMADA_32BIT_SYSCON_SYSRESET
+	bool "Support Armada XP/375/38x/39x sysreset via driver model"
+	depends on ARMADA_32BIT
+	depends on SYSRESET
+	select ARMADA_32BIT_SYSCON
+	help
+	  Build support for Armada XP/375/38x/39x system reset via driver model.
+
 source "board/solidrun/clearfog/Kconfig"
 source "board/kobol/helios4/Kconfig"
 

arch/arm/mach-mvebu/Makefile

@@ -28,7 +28,7 @@ obj-$(CONFIG_ARMADA_38X) += ../../../drivers/ddr/marvell/a38x/xor.o
 obj-$(CONFIG_ARMADA_XP) += ../../../drivers/ddr/marvell/axp/xor.o
 obj-$(CONFIG_ARMADA_MSYS) += ../../../drivers/ddr/marvell/axp/xor.o
 
-obj-$(CONFIG_ARMADA_32BIT_SYSCON_RESET) += system-controller.o
+obj-$(CONFIG_ARMADA_32BIT_SYSCON) += system-controller.o
 
 ifdef CONFIG_ARMADA_38X
 obj-$(CONFIG_MVEBU_EFUSE) += efuse.o

arch/arm/mach-mvebu/cpu.c

@@ -52,6 +52,7 @@ void lowlevel_init(void)
 	 */
 }
 
+#if defined(CONFIG_SPL_BUILD) || !defined(CONFIG_ARMADA_32BIT_SYSCON_SYSRESET)
 void reset_cpu(void)
 {
 	struct mvebu_system_registers *reg =
@@ -62,6 +63,7 @@ void reset_cpu(void)
 	while (1)
 		;
 }
+#endif
 
 u32 get_boot_device(void)
 {

arch/arm/mach-mvebu/system-controller.c

@@ -10,11 +10,24 @@
 #include <regmap.h>
 #include <reset-uclass.h>
 #include <syscon.h>
+#include <sysreset.h>
 #include <asm/io.h>
 
-#define MVEBU_SOC_CONTROL_1_REG 0x4
+#define MVEBU_SOC_CONTROL_1_REG		0x4
 
-#define MVEBU_PCIE_ID 0
+#if defined(CONFIG_ARMADA_375)
+# define MVEBU_RSTOUTN_MASK_REG		0x54
+# define MVEBU_SYS_SOFT_RST_REG		0x58
+#else
+# define MVEBU_RSTOUTN_MASK_REG		0x60
+# define MVEBU_SYS_SOFT_RST_REG		0x64
+#endif
+
+#define MVEBU_GLOBAL_SOFT_RST_BIT	BIT(0)
+
+#define MVEBU_PCIE_ID			0
+
+#if IS_ENABLED(CONFIG_ARMADA_32BIT_SYSCON_RESET)
 
 static int mvebu_reset_of_xlate(struct reset_ctl *rst,
 				struct ofnode_phandle_args *args)
@@ -90,11 +103,65 @@ U_BOOT_DRIVER(mvebu_reset) = {
 	.ops = &mvebu_reset_ops,
 };
 
+#endif /* IS_ENABLED(CONFIG_ARMADA_32BIT_SYSCON_RESET) */
+
+#if IS_ENABLED(CONFIG_ARMADA_32BIT_SYSCON_SYSRESET)
+
+static int mvebu_sysreset_request(struct udevice *dev, enum sysreset_t type)
+{
+	struct regmap *regmap = syscon_get_regmap(dev->parent);
+	uint bit;
+
+	if (type != SYSRESET_COLD)
+		return -EPROTONOSUPPORT;
+
+	bit = MVEBU_GLOBAL_SOFT_RST_BIT;
+
+	regmap_update_bits(regmap, MVEBU_RSTOUTN_MASK_REG, bit, bit);
+	regmap_update_bits(regmap, MVEBU_SYS_SOFT_RST_REG, bit, bit);
+
+	/* Loop while waiting for the reset */
+	while (1)
+		;
+
+	return 0;
+}
+
+static struct sysreset_ops mvebu_sysreset_ops = {
+	.request = mvebu_sysreset_request,
+};
+
+U_BOOT_DRIVER(mvebu_sysreset) = {
+	.name = "mvebu-sysreset",
+	.id = UCLASS_SYSRESET,
+	.ops = &mvebu_sysreset_ops,
+};
+
+#endif /* IS_ENABLED(CONFIG_ARMADA_32BIT_SYSCON_SYSRESET) */
+
 static int mvebu_syscon_bind(struct udevice *dev)
 {
+	int ret = 0;
+
 	/* bind also mvebu-reset, with the same ofnode */
-	return device_bind_driver_to_node(dev, "mvebu-reset", "mvebu-reset",
-					  dev_ofnode(dev), NULL);
+	if (IS_ENABLED(CONFIG_ARMADA_32BIT_SYSCON_RESET)) {
+		ret = device_bind_driver_to_node(dev, "mvebu-reset",
+						 "mvebu-reset", dev_ofnode(dev),
+						 NULL);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* bind also mvebu-sysreset, with the same ofnode */
+	if (IS_ENABLED(CONFIG_ARMADA_32BIT_SYSCON_SYSRESET)) {
+		ret = device_bind_driver_to_node(dev, "mvebu-sysreset",
+						 "mvebu-sysreset",
+						 dev_ofnode(dev), NULL);
+		if (ret < 0)
+			return ret;
+	}
+
+	return ret;
 }
 
 static const struct udevice_id mvebu_syscon_of_match[] = {