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-rw-r--r--Documentation/devicetree/bindings/clock/ti-keystone-pllctrl.txt20
-rw-r--r--Documentation/devicetree/bindings/power/reset/keystone-reset.txt67
-rw-r--r--drivers/power/reset/Kconfig8
-rw-r--r--drivers/power/reset/Makefile1
-rw-r--r--drivers/power/reset/keystone-reset.c166
5 files changed, 262 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/ti-keystone-pllctrl.txt b/Documentation/devicetree/bindings/clock/ti-keystone-pllctrl.txt
new file mode 100644
index 00000000000..3e6a81e9980
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/ti-keystone-pllctrl.txt
@@ -0,0 +1,20 @@
+* Device tree bindings for Texas Instruments keystone pll controller
+
+The main pll controller used to drive theC66x CorePacs, the switch fabric,
+and a majority of the peripheral clocks (all but the ARM CorePacs, DDR3 and
+the NETCP modules) requires a PLL Controller to manage the various clock
+divisions, gating, and synchronization.
+
+Required properties:
+
+- compatible: "ti,keystone-pllctrl", "syscon"
+
+- reg: contains offset/length value for pll controller
+ registers space.
+
+Example:
+
+pllctrl: pll-controller@0x02310000 {
+ compatible = "ti,keystone-pllctrl", "syscon";
+ reg = <0x02310000 0x200>;
+};
diff --git a/Documentation/devicetree/bindings/power/reset/keystone-reset.txt b/Documentation/devicetree/bindings/power/reset/keystone-reset.txt
new file mode 100644
index 00000000000..c82f12e2d85
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/keystone-reset.txt
@@ -0,0 +1,67 @@
+* Device tree bindings for Texas Instruments keystone reset
+
+This node is intended to allow SoC reset in case of software reset
+of selected watchdogs.
+
+The Keystone SoCs can contain up to 4 watchdog timers to reset
+SoC. Each watchdog timer event input is connected to the Reset Mux
+block. The Reset Mux block can be configured to cause reset or not.
+
+Additionally soft or hard reset can be configured.
+
+Required properties:
+
+- compatible: ti,keystone-reset
+
+- ti,syscon-pll: phandle/offset pair. The phandle to syscon used to
+ access pll controller registers and the offset to use
+ reset control registers.
+
+- ti,syscon-dev: phandle/offset pair. The phandle to syscon used to
+ access device state control registers and the offset
+ in order to use mux block registers for all watchdogs.
+
+Optional properties:
+
+- ti,soft-reset: Boolean option indicating soft reset.
+ By default hard reset is used.
+
+- ti,wdt-list: WDT list that can cause SoC reset. It's not related
+ to WDT driver, it's just needed to enable a SoC related
+ reset that's triggered by one of WDTs. The list is
+ in format: <0>, <2>; It can be in random order and
+ begins from 0 to 3, as keystone can contain up to 4 SoC
+ reset watchdogs and can be in random order.
+
+Example 1:
+Setup keystone reset so that in case software reset or
+WDT0 is triggered it issues hard reset for SoC.
+
+pllctrl: pll-controller@02310000 {
+ compatible = "ti,keystone-pllctrl", "syscon";
+ reg = <0x02310000 0x200>;
+};
+
+devctrl: device-state-control@02620000 {
+ compatible = "ti,keystone-devctrl", "syscon";
+ reg = <0x02620000 0x1000>;
+};
+
+rstctrl: reset-controller {
+ compatible = "ti,keystone-reset";
+ ti,syscon-pll = <&pllctrl 0xe4>;
+ ti,syscon-dev = <&devctrl 0x328>;
+ ti,wdt-list = <0>;
+};
+
+Example 2:
+Setup keystone reset so that in case of software reset or
+WDT0 or WDT2 is triggered it issues soft reset for SoC.
+
+rstctrl: reset-controller {
+ compatible = "ti,keystone-reset";
+ ti,syscon-pll = <&pllctrl 0xe4>;
+ ti,syscon-dev = <&devctrl 0x328>;
+ ti,wdt-list = <0>, <2>;
+ ti,soft-reset;
+};
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 67aeb6ec08f..736b9199424 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -64,3 +64,11 @@ config POWER_RESET_XGENE
depends on POWER_RESET
help
Reboot support for the APM SoC X-Gene Eval boards.
+
+config POWER_RESET_KEYSTONE
+ bool "Keystone reset driver"
+ depends on ARCH_KEYSTONE
+ select MFD_SYSCON
+ help
+ Reboot support for the KEYSTONE SoCs.
+
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 950fdc011c7..618541b7020 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-reboot.o
obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
+obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o
diff --git a/drivers/power/reset/keystone-reset.c b/drivers/power/reset/keystone-reset.c
new file mode 100644
index 00000000000..408a18fd91c
--- /dev/null
+++ b/drivers/power/reset/keystone-reset.c
@@ -0,0 +1,166 @@
+/*
+ * TI keystone reboot driver
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated. http://www.ti.com/
+ *
+ * Author: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+#include <asm/system_misc.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_platform.h>
+
+#define RSTYPE_RG 0x0
+#define RSCTRL_RG 0x4
+#define RSCFG_RG 0x8
+#define RSISO_RG 0xc
+
+#define RSCTRL_KEY_MASK 0x0000ffff
+#define RSCTRL_RESET_MASK BIT(16)
+#define RSCTRL_KEY 0x5a69
+
+#define RSMUX_OMODE_MASK 0xe
+#define RSMUX_OMODE_RESET_ON 0xa
+#define RSMUX_OMODE_RESET_OFF 0x0
+#define RSMUX_LOCK_MASK 0x1
+#define RSMUX_LOCK_SET 0x1
+
+#define RSCFG_RSTYPE_SOFT 0x300f
+#define RSCFG_RSTYPE_HARD 0x0
+
+#define WDT_MUX_NUMBER 0x4
+
+static int rspll_offset;
+static struct regmap *pllctrl_regs;
+
+/**
+ * rsctrl_enable_rspll_write - enable access to RSCTRL, RSCFG
+ * To be able to access to RSCTRL, RSCFG registers
+ * we have to write a key before
+ */
+static inline int rsctrl_enable_rspll_write(void)
+{
+ return regmap_update_bits(pllctrl_regs, rspll_offset + RSCTRL_RG,
+ RSCTRL_KEY_MASK, RSCTRL_KEY);
+}
+
+static void rsctrl_restart(enum reboot_mode mode, const char *cmd)
+{
+ /* enable write access to RSTCTRL */
+ rsctrl_enable_rspll_write();
+
+ /* reset the SOC */
+ regmap_update_bits(pllctrl_regs, rspll_offset + RSCTRL_RG,
+ RSCTRL_RESET_MASK, 0);
+}
+
+static struct of_device_id rsctrl_of_match[] = {
+ {.compatible = "ti,keystone-reset", },
+ {},
+};
+
+static int rsctrl_probe(struct platform_device *pdev)
+{
+ int i;
+ int ret;
+ u32 val;
+ unsigned int rg;
+ u32 rsmux_offset;
+ struct regmap *devctrl_regs;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+
+ if (!np)
+ return -ENODEV;
+
+ /* get regmaps */
+ pllctrl_regs = syscon_regmap_lookup_by_phandle(np, "ti,syscon-pll");
+ if (IS_ERR(pllctrl_regs))
+ return PTR_ERR(pllctrl_regs);
+
+ devctrl_regs = syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
+ if (IS_ERR(devctrl_regs))
+ return PTR_ERR(devctrl_regs);
+
+ ret = of_property_read_u32_index(np, "ti,syscon-pll", 1, &rspll_offset);
+ if (ret) {
+ dev_err(dev, "couldn't read the reset pll offset!\n");
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32_index(np, "ti,syscon-dev", 1, &rsmux_offset);
+ if (ret) {
+ dev_err(dev, "couldn't read the rsmux offset!\n");
+ return -EINVAL;
+ }
+
+ /* set soft/hard reset */
+ val = of_property_read_bool(np, "ti,soft-reset");
+ val = val ? RSCFG_RSTYPE_SOFT : RSCFG_RSTYPE_HARD;
+
+ ret = rsctrl_enable_rspll_write();
+ if (ret)
+ return ret;
+
+ ret = regmap_write(pllctrl_regs, rspll_offset + RSCFG_RG, val);
+ if (ret)
+ return ret;
+
+ arm_pm_restart = rsctrl_restart;
+
+ /* disable a reset isolation for all module clocks */
+ ret = regmap_write(pllctrl_regs, rspll_offset + RSISO_RG, 0);
+ if (ret)
+ return ret;
+
+ /* enable a reset for watchdogs from wdt-list */
+ for (i = 0; i < WDT_MUX_NUMBER; i++) {
+ ret = of_property_read_u32_index(np, "ti,wdt-list", i, &val);
+ if (ret == -EOVERFLOW && !i) {
+ dev_err(dev, "ti,wdt-list property has to contain at"
+ "least one entry\n");
+ return -EINVAL;
+ } else if (ret) {
+ break;
+ }
+
+ if (val >= WDT_MUX_NUMBER) {
+ dev_err(dev, "ti,wdt-list property can contain"
+ "only numbers < 4\n");
+ return -EINVAL;
+ }
+
+ rg = rsmux_offset + val * 4;
+
+ ret = regmap_update_bits(devctrl_regs, rg, RSMUX_OMODE_MASK,
+ RSMUX_OMODE_RESET_ON |
+ RSMUX_LOCK_SET);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver rsctrl_driver = {
+ .probe = rsctrl_probe,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = KBUILD_MODNAME,
+ .of_match_table = rsctrl_of_match,
+ },
+};
+module_platform_driver(rsctrl_driver);
+
+MODULE_AUTHOR("Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>");
+MODULE_DESCRIPTION("Texas Instruments keystone reset driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" KBUILD_MODNAME);