diff options
Diffstat (limited to 'drivers/reset')
-rw-r--r-- | drivers/reset/Kconfig | 17 | ||||
-rw-r--r-- | drivers/reset/Makefile | 4 | ||||
-rw-r--r-- | drivers/reset/core.c | 23 | ||||
-rw-r--r-- | drivers/reset/reset-gemini.c | 110 | ||||
-rw-r--r-- | drivers/reset/reset-ti-sci.c | 269 | ||||
-rw-r--r-- | drivers/reset/sti/reset-syscfg.c | 6 |
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; |