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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-04 14:47:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-04 14:47:47 -0700
commite8547112910540afb71589ee807ae6a4259f9755 (patch)
tree7d3d7eb17be4e6d2b181bffc4d471e93063674b4 /drivers/reset
parent9ce32ac8f83729aca9f45ce9598dbc5451d1044b (diff)
parentffe3744a591fdce695da6b891378261e2caedc69 (diff)
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Arnd Bergmann: "New SoC specific drivers: - NVIDIA Tegra PM Domain support for newer SoCs (Tegra186 and later) based on the "BPMP" firmware - Clocksource and system controller drivers for the newly added Action Semi platforms (both arm and arm64). Reset subsystem, merged through arm-soc by tradition: - New drivers for Altera Stratix10, TI Keystone and Cortina Gemini SoCs - Various subsystem-wide cleanups Updates for existing SoC-specific drivers - TI GPMC (General Purpose Memory Controller) - Mediatek "scpsys" system controller support for MT6797 - Broadcom "brcmstb_gisb" bus arbitrer - ARM SCPI firmware - Renesas "SYSC" system controller One more driver update was submitted for the Freescale/NXP DPAA data path acceleration that has previously been used on PowerPC chips. I ended up postponing the merge until some API questions for its unusual MMIO access are resolved" * tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (35 commits) clocksource: owl: Add S900 support clocksource: Add Owl timer soc: renesas: rcar-sysc: Use GENPD_FLAG_ALWAYS_ON firmware: tegra: Fix locking bugs in BPMP soc/tegra: flowctrl: Fix error handling soc/tegra: bpmp: Implement generic PM domains soc/tegra: bpmp: Update ABI header PM / Domains: Allow overriding the ->xlate() callback soc: brcmstb: enable drivers for ARM64 and BMIPS soc: renesas: Rework Kconfig and Makefile logic reset: Add the TI SCI reset driver dt-bindings: reset: Add TI SCI reset binding reset: use kref for reference counting soc: qcom: smsm: Improve error handling, quiesce probe deferral cpufreq: scpi: use new scpi_ops functions to remove duplicate code firmware: arm_scpi: add support to populate OPPs and get transition latency dt-bindings: reset: Add reset manager offsets for Stratix10 memory: omap-gpmc: add error message if bank-width property is absent memory: omap-gpmc: make dts snippet include semicolon reset: Add a Gemini reset controller ...
Diffstat (limited to 'drivers/reset')
-rw-r--r--drivers/reset/Kconfig17
-rw-r--r--drivers/reset/Makefile4
-rw-r--r--drivers/reset/core.c23
-rw-r--r--drivers/reset/reset-gemini.c110
-rw-r--r--drivers/reset/reset-ti-sci.c269
-rw-r--r--drivers/reset/sti/reset-syscfg.c6
6 files changed, 415 insertions, 14 deletions
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index d21c07ccc94e..608c071e4bbf 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -34,6 +34,13 @@ config RESET_BERLIN
help
This enables the reset controller driver for Marvell Berlin SoCs.
+config RESET_GEMINI
+ bool "Gemini Reset Driver" if COMPILE_TEST
+ default ARCH_GEMINI
+ select MFD_SYSCON
+ help
+ This enables the reset controller driver for Cortina Systems Gemini.
+
config RESET_IMX7
bool "i.MX7 Reset Driver" if COMPILE_TEST
default SOC_IMX7D
@@ -80,7 +87,15 @@ config RESET_SUNXI
help
This enables the reset driver for Allwinner SoCs.
-config TI_SYSCON_RESET
+config RESET_TI_SCI
+ tristate "TI System Control Interface (TI-SCI) reset driver"
+ depends on TI_SCI_PROTOCOL
+ help
+ This enables the reset driver support over TI System Control Interface
+ available on some new TI's SoCs. If you wish to use reset resources
+ managed by the TI System Controller, say Y here. Otherwise, say N.
+
+config RESET_TI_SYSCON
tristate "TI SYSCON Reset Driver"
depends on HAS_IOMEM
select MFD_SYSCON
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 02a74db94339..7081f9da2599 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -5,6 +5,7 @@ obj-$(CONFIG_ARCH_TEGRA) += tegra/
obj-$(CONFIG_RESET_A10SR) += reset-a10sr.o
obj-$(CONFIG_RESET_ATH79) += reset-ath79.o
obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
+obj-$(CONFIG_RESET_GEMINI) += reset-gemini.o
obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o
obj-$(CONFIG_RESET_MESON) += reset-meson.o
@@ -13,7 +14,8 @@ obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o
obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
obj-$(CONFIG_RESET_STM32) += reset-stm32.o
obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
-obj-$(CONFIG_TI_SYSCON_RESET) += reset-ti-syscon.o
+obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
+obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o
obj-$(CONFIG_RESET_ZX2967) += reset-zx2967.o
obj-$(CONFIG_RESET_ZYNQ) += reset-zynq.o
diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index cd739d2fa160..0090784ff410 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -13,6 +13,7 @@
#include <linux/err.h>
#include <linux/export.h>
#include <linux/kernel.h>
+#include <linux/kref.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/reset.h>
@@ -40,7 +41,7 @@ struct reset_control {
struct reset_controller_dev *rcdev;
struct list_head list;
unsigned int id;
- unsigned int refcnt;
+ struct kref refcnt;
bool shared;
atomic_t deassert_count;
atomic_t triggered_count;
@@ -288,7 +289,7 @@ static struct reset_control *__reset_control_get_internal(
if (WARN_ON(!rstc->shared || !shared))
return ERR_PTR(-EBUSY);
- rstc->refcnt++;
+ kref_get(&rstc->refcnt);
return rstc;
}
}
@@ -302,18 +303,18 @@ static struct reset_control *__reset_control_get_internal(
rstc->rcdev = rcdev;
list_add(&rstc->list, &rcdev->reset_control_head);
rstc->id = index;
- rstc->refcnt = 1;
+ kref_init(&rstc->refcnt);
rstc->shared = shared;
return rstc;
}
-static void __reset_control_put_internal(struct reset_control *rstc)
+static void __reset_control_release(struct kref *kref)
{
- lockdep_assert_held(&reset_list_mutex);
+ struct reset_control *rstc = container_of(kref, struct reset_control,
+ refcnt);
- if (--rstc->refcnt)
- return;
+ lockdep_assert_held(&reset_list_mutex);
module_put(rstc->rcdev->owner);
@@ -321,6 +322,13 @@ static void __reset_control_put_internal(struct reset_control *rstc)
kfree(rstc);
}
+static void __reset_control_put_internal(struct reset_control *rstc)
+{
+ lockdep_assert_held(&reset_list_mutex);
+
+ kref_put(&rstc->refcnt, __reset_control_release);
+}
+
struct reset_control *__of_reset_control_get(struct device_node *node,
const char *id, int index, bool shared,
bool optional)
@@ -400,7 +408,6 @@ EXPORT_SYMBOL_GPL(__reset_control_get);
* reset_control_put - free the reset controller
* @rstc: reset controller
*/
-
void reset_control_put(struct reset_control *rstc)
{
if (IS_ERR_OR_NULL(rstc))
diff --git a/drivers/reset/reset-gemini.c b/drivers/reset/reset-gemini.c
new file mode 100644
index 000000000000..a2478997c75b
--- /dev/null
+++ b/drivers/reset/reset-gemini.c
@@ -0,0 +1,110 @@
+/*
+ * Cortina Gemini Reset controller driver
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * 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/err.h>
+#include <linux/init.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <dt-bindings/reset/cortina,gemini-reset.h>
+
+/**
+ * struct gemini_reset - gemini reset controller
+ * @map: regmap to access the containing system controller
+ * @rcdev: reset controller device
+ */
+struct gemini_reset {
+ struct regmap *map;
+ struct reset_controller_dev rcdev;
+};
+
+#define GEMINI_GLOBAL_SOFT_RESET 0x0c
+
+#define to_gemini_reset(p) \
+ container_of((p), struct gemini_reset, rcdev)
+
+/*
+ * This is a self-deasserting reset controller.
+ */
+static int gemini_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct gemini_reset *gr = to_gemini_reset(rcdev);
+
+ /* Manual says to always set BIT 30 (CPU1) to 1 */
+ return regmap_write(gr->map,
+ GEMINI_GLOBAL_SOFT_RESET,
+ BIT(GEMINI_RESET_CPU1) | BIT(id));
+}
+
+static int gemini_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct gemini_reset *gr = to_gemini_reset(rcdev);
+ u32 val;
+ int ret;
+
+ ret = regmap_read(gr->map, GEMINI_GLOBAL_SOFT_RESET, &val);
+ if (ret)
+ return ret;
+
+ return !!(val & BIT(id));
+}
+
+static const struct reset_control_ops gemini_reset_ops = {
+ .reset = gemini_reset,
+ .status = gemini_reset_status,
+};
+
+static int gemini_reset_probe(struct platform_device *pdev)
+{
+ struct gemini_reset *gr;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ int ret;
+
+ gr = devm_kzalloc(dev, sizeof(*gr), GFP_KERNEL);
+ if (!gr)
+ return -ENOMEM;
+
+ gr->map = syscon_node_to_regmap(np);
+ if (IS_ERR(gr->map)) {
+ ret = PTR_ERR(gr->map);
+ dev_err(dev, "unable to get regmap (%d)", ret);
+ return ret;
+ }
+ gr->rcdev.owner = THIS_MODULE;
+ gr->rcdev.nr_resets = 32;
+ gr->rcdev.ops = &gemini_reset_ops;
+ gr->rcdev.of_node = pdev->dev.of_node;
+
+ ret = devm_reset_controller_register(&pdev->dev, &gr->rcdev);
+ if (ret)
+ return ret;
+
+ dev_info(dev, "registered Gemini reset controller\n");
+ return 0;
+}
+
+static const struct of_device_id gemini_reset_dt_ids[] = {
+ { .compatible = "cortina,gemini-syscon", },
+ { /* sentinel */ },
+};
+
+static struct platform_driver gemini_reset_driver = {
+ .probe = gemini_reset_probe,
+ .driver = {
+ .name = "gemini-reset",
+ .of_match_table = gemini_reset_dt_ids,
+ .suppress_bind_attrs = true,
+ },
+};
+builtin_platform_driver(gemini_reset_driver);
diff --git a/drivers/reset/reset-ti-sci.c b/drivers/reset/reset-ti-sci.c
new file mode 100644
index 000000000000..bf68729ab729
--- /dev/null
+++ b/drivers/reset/reset-ti-sci.c
@@ -0,0 +1,269 @@
+/*
+ * Texas Instrument's System Control Interface (TI-SCI) reset driver
+ *
+ * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Andrew F. Davis <afd@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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+
+/**
+ * struct ti_sci_reset_control - reset control structure
+ * @dev_id: SoC-specific device identifier
+ * @reset_mask: reset mask to use for toggling reset
+ * @lock: synchronize reset_mask read-modify-writes
+ */
+struct ti_sci_reset_control {
+ u32 dev_id;
+ u32 reset_mask;
+ struct mutex lock;
+};
+
+/**
+ * struct ti_sci_reset_data - reset controller information structure
+ * @rcdev: reset controller entity
+ * @dev: reset controller device pointer
+ * @sci: TI SCI handle used for communication with system controller
+ * @idr: idr structure for mapping ids to reset control structures
+ */
+struct ti_sci_reset_data {
+ struct reset_controller_dev rcdev;
+ struct device *dev;
+ const struct ti_sci_handle *sci;
+ struct idr idr;
+};
+
+#define to_ti_sci_reset_data(p) \
+ container_of((p), struct ti_sci_reset_data, rcdev)
+
+/**
+ * ti_sci_reset_set() - program a device's reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to toggle
+ * @assert: boolean flag to indicate assert or deassert
+ *
+ * This is a common internal function used to assert or deassert a device's
+ * reset using the TI SCI protocol. The device's reset is asserted if the
+ * @assert argument is true, or deasserted if @assert argument is false.
+ * The mechanism itself is a read-modify-write procedure, the current device
+ * reset register is read using a TI SCI device operation, the new value is
+ * set or un-set using the reset's mask, and the new reset value written by
+ * using another TI SCI device operation.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_set(struct reset_controller_dev *rcdev,
+ unsigned long id, bool assert)
+{
+ struct ti_sci_reset_data *data = to_ti_sci_reset_data(rcdev);
+ const struct ti_sci_handle *sci = data->sci;
+ const struct ti_sci_dev_ops *dev_ops = &sci->ops.dev_ops;
+ struct ti_sci_reset_control *control;
+ u32 reset_state;
+ int ret;
+
+ control = idr_find(&data->idr, id);
+ if (!control)
+ return -EINVAL;
+
+ mutex_lock(&control->lock);
+
+ ret = dev_ops->get_device_resets(sci, control->dev_id, &reset_state);
+ if (ret)
+ goto out;
+
+ if (assert)
+ reset_state |= control->reset_mask;
+ else
+ reset_state &= ~control->reset_mask;
+
+ ret = dev_ops->set_device_resets(sci, control->dev_id, reset_state);
+out:
+ mutex_unlock(&control->lock);
+
+ return ret;
+}
+
+/**
+ * ti_sci_reset_assert() - assert device reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to be asserted
+ *
+ * This function implements the reset driver op to assert a device's reset
+ * using the TI SCI protocol. This invokes the function ti_sci_reset_set()
+ * with the corresponding parameters as passed in, but with the @assert
+ * argument set to true for asserting the reset.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return ti_sci_reset_set(rcdev, id, true);
+}
+
+/**
+ * ti_sci_reset_deassert() - deassert device reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to be deasserted
+ *
+ * This function implements the reset driver op to deassert a device's reset
+ * using the TI SCI protocol. This invokes the function ti_sci_reset_set()
+ * with the corresponding parameters as passed in, but with the @assert
+ * argument set to false for deasserting the reset.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return ti_sci_reset_set(rcdev, id, false);
+}
+
+/**
+ * ti_sci_reset_status() - check device reset status
+ * @rcdev: reset controller entity
+ * @id: ID of reset to be checked
+ *
+ * This function implements the reset driver op to return the status of a
+ * device's reset using the TI SCI protocol. The reset register value is read
+ * by invoking the TI SCI device operation .get_device_resets(), and the
+ * status of the specific reset is extracted and returned using this reset's
+ * reset mask.
+ *
+ * Return: 0 if reset is deasserted, or a non-zero value if reset is asserted
+ */
+static int ti_sci_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct ti_sci_reset_data *data = to_ti_sci_reset_data(rcdev);
+ const struct ti_sci_handle *sci = data->sci;
+ const struct ti_sci_dev_ops *dev_ops = &sci->ops.dev_ops;
+ struct ti_sci_reset_control *control;
+ u32 reset_state;
+ int ret;
+
+ control = idr_find(&data->idr, id);
+ if (!control)
+ return -EINVAL;
+
+ ret = dev_ops->get_device_resets(sci, control->dev_id, &reset_state);
+ if (ret)
+ return ret;
+
+ return reset_state & control->reset_mask;
+}
+
+static const struct reset_control_ops ti_sci_reset_ops = {
+ .assert = ti_sci_reset_assert,
+ .deassert = ti_sci_reset_deassert,
+ .status = ti_sci_reset_status,
+};
+
+/**
+ * ti_sci_reset_of_xlate() - translate a set of OF arguments to a reset ID
+ * @rcdev: reset controller entity
+ * @reset_spec: OF reset argument specifier
+ *
+ * This function performs the translation of the reset argument specifier
+ * values defined in a reset consumer device node. The function allocates a
+ * reset control structure for that device reset, and will be used by the
+ * driver for performing any reset functions on that reset. An idr structure
+ * is allocated and used to map to the reset control structure. This idr
+ * is used by the driver to do reset lookups.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_of_xlate(struct reset_controller_dev *rcdev,
+ const struct of_phandle_args *reset_spec)
+{
+ struct ti_sci_reset_data *data = to_ti_sci_reset_data(rcdev);
+ struct ti_sci_reset_control *control;
+
+ if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
+ return -EINVAL;
+
+ control = devm_kzalloc(data->dev, sizeof(*control), GFP_KERNEL);
+ if (!control)
+ return -ENOMEM;
+
+ control->dev_id = reset_spec->args[0];
+ control->reset_mask = reset_spec->args[1];
+ mutex_init(&control->lock);
+
+ return idr_alloc(&data->idr, control, 0, 0, GFP_KERNEL);
+}
+
+static const struct of_device_id ti_sci_reset_of_match[] = {
+ { .compatible = "ti,sci-reset", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ti_sci_reset_of_match);
+
+static int ti_sci_reset_probe(struct platform_device *pdev)
+{
+ struct ti_sci_reset_data *data;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->sci = devm_ti_sci_get_handle(&pdev->dev);
+ if (IS_ERR(data->sci))
+ return PTR_ERR(data->sci);
+
+ data->rcdev.ops = &ti_sci_reset_ops;
+ data->rcdev.owner = THIS_MODULE;
+ data->rcdev.of_node = pdev->dev.of_node;
+ data->rcdev.of_reset_n_cells = 2;
+ data->rcdev.of_xlate = ti_sci_reset_of_xlate;
+ data->dev = &pdev->dev;
+ idr_init(&data->idr);
+
+ platform_set_drvdata(pdev, data);
+
+ return reset_controller_register(&data->rcdev);
+}
+
+static int ti_sci_reset_remove(struct platform_device *pdev)
+{
+ struct ti_sci_reset_data *data = platform_get_drvdata(pdev);
+
+ reset_controller_unregister(&data->rcdev);
+
+ idr_destroy(&data->idr);
+
+ return 0;
+}
+
+static struct platform_driver ti_sci_reset_driver = {
+ .probe = ti_sci_reset_probe,
+ .remove = ti_sci_reset_remove,
+ .driver = {
+ .name = "ti-sci-reset",
+ .of_match_table = ti_sci_reset_of_match,
+ },
+};
+module_platform_driver(ti_sci_reset_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_DESCRIPTION("TI System Control Interface (TI SCI) Reset driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/reset/sti/reset-syscfg.c b/drivers/reset/sti/reset-syscfg.c
index 9bd57a5eee72..7e0f2aa55ba7 100644
--- a/drivers/reset/sti/reset-syscfg.c
+++ b/drivers/reset/sti/reset-syscfg.c
@@ -145,16 +145,14 @@ static int syscfg_reset_controller_register(struct device *dev,
const struct syscfg_reset_controller_data *data)
{
struct syscfg_reset_controller *rc;
- size_t size;
int i, err;
rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL);
if (!rc)
return -ENOMEM;
- size = sizeof(struct syscfg_reset_channel) * data->nr_channels;
-
- rc->channels = devm_kzalloc(dev, size, GFP_KERNEL);
+ rc->channels = devm_kcalloc(dev, data->nr_channels,
+ sizeof(*rc->channels), GFP_KERNEL);
if (!rc->channels)
return -ENOMEM;

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