2014-02-28 18:11:01

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH 0/5] Introduce keystone reset driver

These patches introduce keystone reset driver.

The keystone SoC can be rebooted in several ways. By external reset
pin, by soft and by watchdogs. This driver allows software reset or reset
by one of the watchdogs. Also added opportunity to set soft/hard reset type.

Based on v3.14-rc4

CC: Dmitry Eremin-Solenikov <[email protected]>
CC: David Woodhouse <[email protected]>
CC: Grant Likely <[email protected]>
CC: Rob Herring <[email protected]>
CC: Pawel Moll <[email protected]>
CC: Mark Rutland <[email protected]>
CC: Ian Campbell <[email protected]>
CC: Kumar Gala <[email protected]>
CC: Rob Landley <[email protected]>
CC: Santosh Shilimkar <[email protected]>
CC: Russell King <[email protected]>

Ivan Khoronzhuk (5):
Power: reset: keystone-reset: introduce keystone reset driver
Power: reset: add bindings for keystone reset driver
ARM: keystone: remove redundant reset stuff
ARM: dts: keystone: update reset node to work with reset driver
ARM: keystone: enable reset driver support

.../bindings/power/reset/keystone-reset.txt | 59 +++++++
arch/arm/boot/dts/keystone.dtsi | 4 +-
arch/arm/configs/keystone_defconfig | 3 +
arch/arm/mach-keystone/keystone.c | 35 -----
drivers/power/reset/Kconfig | 7 +
drivers/power/reset/Makefile | 1 +
drivers/power/reset/keystone-reset.c | 171 +++++++++++++++++++++
7 files changed, 244 insertions(+), 36 deletions(-)
create mode 100644 Documentation/devicetree/bindings/power/reset/keystone-reset.txt
create mode 100644 drivers/power/reset/keystone-reset.c

--
1.8.3.2


2014-02-28 18:09:59

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH 3/5] ARM: keystone: remove redundant reset stuff

Remove reset stuff in flavour of using keystone reset driver:
driver/power/reset/keystone-reset.c

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

CC: Santosh Shilimkar <[email protected]>
CC: Russell King <[email protected]>

arch/arm/mach-keystone/keystone.c | 35 -----------------------------------
1 file changed, 35 deletions(-)

diff --git a/arch/arm/mach-keystone/keystone.c b/arch/arm/mach-keystone/keystone.c
index 6e6bb7d..4d46e30 100644
--- a/arch/arm/mach-keystone/keystone.c
+++ b/arch/arm/mach-keystone/keystone.c
@@ -23,24 +23,8 @@

#include "keystone.h"

-#define PLL_RESET_WRITE_KEY_MASK 0xffff0000
-#define PLL_RESET_WRITE_KEY 0x5a69
-#define PLL_RESET BIT(16)
-
-static void __iomem *keystone_rstctrl;
-
static void __init keystone_init(void)
{
- struct device_node *node;
-
- node = of_find_compatible_node(NULL, NULL, "ti,keystone-reset");
- if (WARN_ON(!node))
- pr_warn("ti,keystone-reset node undefined\n");
-
- keystone_rstctrl = of_iomap(node, 0);
- if (WARN_ON(!keystone_rstctrl))
- pr_warn("ti,keystone-reset iomap error\n");
-
keystone_pm_runtime_init();
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
}
@@ -50,24 +34,6 @@ static const char *keystone_match[] __initconst = {
NULL,
};

-void keystone_restart(enum reboot_mode mode, const char *cmd)
-{
- u32 val;
-
- BUG_ON(!keystone_rstctrl);
-
- /* Enable write access to RSTCTRL */
- val = readl(keystone_rstctrl);
- val &= PLL_RESET_WRITE_KEY_MASK;
- val |= PLL_RESET_WRITE_KEY;
- writel(val, keystone_rstctrl);
-
- /* Reset the SOC */
- val = readl(keystone_rstctrl);
- val &= ~PLL_RESET;
- writel(val, keystone_rstctrl);
-}
-
DT_MACHINE_START(KEYSTONE, "Keystone")
#if defined(CONFIG_ZONE_DMA) && defined(CONFIG_ARM_LPAE)
.dma_zone_size = SZ_2G,
@@ -75,5 +41,4 @@ DT_MACHINE_START(KEYSTONE, "Keystone")
.smp = smp_ops(keystone_smp_ops),
.init_machine = keystone_init,
.dt_compat = keystone_match,
- .restart = keystone_restart,
MACHINE_END
--
1.8.3.2

2014-02-28 18:10:17

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH 1/5] Power: reset: keystone-reset: introduce keystone reset driver

The keystone SoC can be rebooted in several ways. By external reset
pin, by soft and by watchdogs. To allow keystone SoC reset if
watchdog is triggered we have to enable it in reset mux configuration
register regarding of watchdog configuration. Also we need to set
soft/hard reset we are going to use.

So add keystone reset driver to handle all this stuff.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

CC: Dmitry Eremin-Solenikov <[email protected]>
CC: David Woodhouse <[email protected]>
CC: Grant Likely <[email protected]>
CC: Rob Herring <[email protected]>

drivers/power/reset/Kconfig | 7 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/keystone-reset.c | 171 +++++++++++++++++++++++++++++++++++
3 files changed, 179 insertions(+)
create mode 100644 drivers/power/reset/keystone-reset.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 6d452a7..9082a72 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -57,3 +57,10 @@ 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
+ help
+ Reboot support for the KEYSTONE SoCs.
+
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index a5b4a77..802a420 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.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 0000000..73f6e7a
--- /dev/null
+++ b/drivers/power/reset/keystone-reset.c
@@ -0,0 +1,171 @@
+/*
+ * TI keystone reboot driver
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated. http://www.ti.com/
+ *
+ * Author: Ivan Khoronzhuk <[email protected]>
+ *
+ * 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/reboot.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <asm/system_misc.h>
+
+#define RSCTRL_KEY_MASK 0xffff0000
+#define RSCTRL_KEY 0x5a69
+#define RSCTRL_RESET BIT(16)
+
+#define RSCFG_RSTYPE_SOFT 0x300f
+#define RSCFG_RSTYPE_HARD 0x0
+
+#define RSTYPE_RG 0x0
+#define RSCTRL_RG 0x4
+#define RSCFG_RG 0x8
+#define RSISO_RG 0xc
+
+#define RSMUX_OMODE_MASK 0xe
+#define RSMUX_OMODE_RESET_SOC 0xa
+#define RSMUX_OMODE_RESET_OFF 0x0
+#define RSMUX_LOCK_MASK 0x1
+#define RSMUX_LOCK_SET 0x1
+
+#define WDT_MUX_NUMBER 0x4
+
+static void __iomem *rspll_base;
+
+/**
+ * rsctrl_enable_rspll_write - enable access to RSCTRL, RSCFG
+ * To be able to access to RSCTRL, RSCFG registers
+ * we has to write a key before
+ */
+static void rsctrl_enable_rspll_write(void)
+{
+ void __iomem *rstctrl_rg;
+ u32 val;
+
+ rstctrl_rg = rspll_base + RSCTRL_RG;
+ val = readl(rstctrl_rg);
+ val &= RSCTRL_KEY_MASK;
+ val |= RSCTRL_KEY;
+ writel(val, rstctrl_rg);
+}
+
+static void rsctrl_restart(enum reboot_mode mode, const char *cmd)
+{
+ u32 val;
+ void __iomem *rstctrl;
+
+ /* enable write access to RSTCTRL */
+ rsctrl_enable_rspll_write();
+
+ /* reset the SOC */
+ rstctrl = rspll_base + RSCTRL_RG;
+ val = readl(rstctrl);
+ val &= ~RSCTRL_RESET;
+ writel(val, rstctrl);
+}
+
+static struct of_device_id rsctrl_of_match[] = {
+ {.compatible = "ti,keystone-reset", },
+ {},
+};
+
+static int rsctrl_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ void __iomem *rsmux_base;
+ void __iomem *rg;
+ struct resource *res;
+ u32 val;
+ int ret;
+ int i;
+
+ if (!np)
+ return -ENODEV;
+
+ i = of_property_match_string(np, "reg-names", "pllregs");
+ res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+ rspll_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(rspll_base))
+ return PTR_ERR(rspll_base);
+
+ i = of_property_match_string(np, "reg-names", "muxregs");
+ res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+ rsmux_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(rsmux_base))
+ return PTR_ERR(rsmux_base);
+
+ /* set soft/hard reset */
+ val = of_property_read_bool(np, "ti,soft-reset");
+ val = val ? RSCFG_RSTYPE_SOFT : RSCFG_RSTYPE_HARD;
+
+ rsctrl_enable_rspll_write();
+ writel(val, rspll_base + RSCFG_RG);
+
+ arm_pm_restart = rsctrl_restart;
+
+ /* disable reset isolation for all module clocks */
+ writel(0, rspll_base + RSISO_RG);
+
+ /* enable reset for watchdogs from 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_base + val*4;
+
+ val = readl_relaxed(rg);
+ val &= ~RSMUX_OMODE_MASK;
+ val |= RSMUX_OMODE_RESET_SOC | RSMUX_LOCK_SET;
+ writel(val, rg);
+ }
+
+ /* disable reset for watchdogs from not list */
+ for (i = 0; i < WDT_MUX_NUMBER; i++) {
+ rg = rsmux_base + i*4;
+
+ val = readl_relaxed(rg);
+ if (!(val & RSMUX_LOCK_MASK)) {
+ val &= ~RSMUX_OMODE_MASK;
+ val |= RSMUX_OMODE_RESET_OFF | RSMUX_LOCK_SET;
+ writel(val, rg);
+ }
+ }
+
+ devm_iounmap(dev, rsmux_base);
+ 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 <[email protected]>");
+MODULE_DESCRIPTION("Texas Instruments keystone reset driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" KBUILD_MODNAME);
--
1.8.3.2

2014-02-28 18:10:31

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH 5/5] ARM: keystone: enable reset driver support

Enable reset driver support in order to have opportunity
to reboot SoC by watchdog and by software.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

CC: Russell King <[email protected]>
CC: Santosh Shilimkar <[email protected]>

arch/arm/configs/keystone_defconfig | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/arm/configs/keystone_defconfig b/arch/arm/configs/keystone_defconfig
index 4582e16..3f9c688 100644
--- a/arch/arm/configs/keystone_defconfig
+++ b/arch/arm/configs/keystone_defconfig
@@ -130,6 +130,9 @@ CONFIG_SPI=y
CONFIG_SPI_DAVINCI=y
CONFIG_SPI_SPIDEV=y
# CONFIG_HWMON is not set
+CONFIG_POWER_SUPPLY=y
+CONFIG_POWER_RESET=y
+CONFIG_POWER_RESET_KEYSTONE=y
CONFIG_WATCHDOG=y
CONFIG_USB=y
CONFIG_USB_DEBUG=y
--
1.8.3.2

2014-02-28 18:10:25

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH 4/5] ARM: dts: keystone: update reset node to work with reset driver

The reset controller registers are part of the PLL Controller MMRs.
According to TRM there are the following registers:
RSTYPE, RSCTRL, RSCFG and RSISO. Currently declared only one of them,
but that is not enough to correctly setup reset properties, so add
whole range of pll registers - pllregs.

Also add range for reset multiplex registers for SoC on the device.
These registers are located in Bootcfg memory space and needed
to setup behaviour after appropriate watchdog is triggered.

Add "ti,wdt_list" option to declare what watchdog are used to reboot
the SoC.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

CC: Rob Herring <[email protected]>
CC: Pawel Moll <[email protected]>
CC: Mark Rutland <[email protected]>
CC: Ian Campbell <[email protected]>
CC: Kumar Gala <[email protected]>
CC: Russell King <[email protected]>

arch/arm/boot/dts/keystone.dtsi | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/keystone.dtsi b/arch/arm/boot/dts/keystone.dtsi
index 3a83ffe..7092208 100644
--- a/arch/arm/boot/dts/keystone.dtsi
+++ b/arch/arm/boot/dts/keystone.dtsi
@@ -99,7 +99,9 @@

rstctrl: reset-controller {
compatible = "ti,keystone-reset";
- reg = <0x023100e8 4>; /* pll reset control reg */
+ reg = <0x23100e4 0x10>, <0x2620328 0x10>;
+ reg-names = "pllregs", "muxregs";
+ ti,wdt_list = <0>;
};

/include/ "keystone-clocks.dtsi"
--
1.8.3.2

2014-02-28 18:11:33

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH 2/5] Power: reset: add bindings for keystone reset driver

This node is intended to allow SoC reset in case of software reset
or appropriate 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.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

CC: Rob Herring <[email protected]>
CC: Pawel Moll <[email protected]>
CC: Mark Rutland <[email protected]>
CC: Ian Campbell <[email protected]>
CC: Kumar Gala <[email protected]>
CC: Rob Landley <[email protected]>

.../bindings/power/reset/keystone-reset.txt | 59 ++++++++++++++++++++++
1 file changed, 59 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power/reset/keystone-reset.txt

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 0000000..5ad5883
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/keystone-reset.txt
@@ -0,0 +1,59 @@
+* 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
+
+- reg: Contains offset/length value for mux registers.
+
+ reg = <0x23100e4 0x10>,
+ <0x2620328 0x10>;
+
+-reg-names: Contains two ranges "pllregs" and "muxregs".
+ "pllregs" - PLL reset control regs: RSTYPE, RSCTRL,
+ RSCFG, RSISO.
+ "muxregs" - 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.
+ The list in format: <0>, <2>;
+ Begins from 0 to 3, as keystone can contain up
+ to 4 SoC reset watchdogs.
+
+Example 1:
+Setup keystone reset so that in case software reset or
+WDT1 is triggered it issues hard reset for SoC.
+
+rstctrl: reset-controller {
+ compatible = "ti,keystone-reset";
+ reg = <0x23100e4 0x10>,
+ <0x2620328 0x10>;
+ reg-names = "pllregs", "muxregs";
+ ti,wdt_list = <0>;
+};
+
+Example 2:
+Setup keystone reset so that in case of software reset or
+WDT1 or WDT3 is triggered it issues soft reset for SoC.
+
+rstctrl: reset-controller {
+ compatible = "ti,keystone-reset";
+ reg = <0x23100e4 0x10>,
+ <0x2620328 0x10>;
+ reg-names = "pllregs", "muxregs";
+ ti,wdt_list = <0>, <2>;
+ ti,soft-reset;
+};
--
1.8.3.2