diff --git a/Documentation/devicetree/bindings/reset/ti,sci-reset.txt b/Documentation/devicetree/bindings/reset/ti,sci-reset.txt new file mode 100644 index 000000000000..8b1cf022f18a --- /dev/null +++ b/Documentation/devicetree/bindings/reset/ti,sci-reset.txt @@ -0,0 +1,62 @@ +Texas Instruments System Control Interface (TI-SCI) Reset Controller +===================================================================== + +Some TI SoCs contain a system controller (like the Power Management Micro +Controller (PMMC) on Keystone 66AK2G SoC) that are responsible for controlling +the state of the various hardware modules present on the SoC. Communication +between the host processor running an OS and the system controller happens +through a protocol called TI System Control Interface (TI-SCI protocol). +For TI SCI details, please refer to the document, +Documentation/devicetree/bindings/arm/keystone/ti,sci.txt + +TI-SCI Reset Controller Node +============================ +This reset controller node uses the TI SCI protocol to perform the reset +management of various hardware modules present on the SoC. Must be a child +node of the associated TI-SCI system controller node. + +Required properties: +-------------------- + - compatible : Should be "ti,sci-reset" + - #reset-cells : Should be 2. Please see the reset consumer node below for + usage details. + +TI-SCI Reset Consumer Nodes +=========================== +Each of the reset consumer nodes should have the following properties, +in addition to their own properties. + +Required properties: +-------------------- + - resets : A phandle and reset specifier pair, one pair for each reset + signal that affects the device, or that the device manages. + The phandle should point to the TI-SCI reset controller node, + and the reset specifier should have 2 cell-values. The first + cell should contain the device ID. The second cell should + contain the reset mask value used by system controller. + Please refer to the protocol documentation for these values + to be used for different devices, + http://processors.wiki.ti.com/index.php/TISCI#66AK2G02_Data + +Please also refer to Documentation/devicetree/bindings/reset/reset.txt for +common reset controller usage by consumers. + +Example: +-------- +The following example demonstrates both a TI-SCI reset controller node and a +consumer (a DSP device) on the 66AK2G SoC. + +pmmc: pmmc { + compatible = "ti,k2g-sci"; + + k2g_reset: reset-controller { + compatible = "ti,sci-reset"; + #reset-cells = <2>; + }; +}; + +dsp0: dsp@10800000 { + ... + resets = <&k2g_reset 0x0046 0x1>; + ... +}; diff --git a/MAINTAINERS b/MAINTAINERS index 053c3bdd1fe5..378133ba441a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12633,6 +12633,8 @@ F: include/linux/soc/ti/ti_sci_protocol.h F: Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt F: include/dt-bindings/genpd/k2g.h F: drivers/soc/ti/ti_sci_pm_domains.c +F: Documentation/devicetree/bindings/reset/ti,sci-reset.txt +F: drivers/reset/reset-ti-sci.c THANKO'S RAREMONO AM/FM/SW RADIO RECEIVER USB DRIVER M: Hans Verkuil diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index 61fabf6ddaec..608c071e4bbf 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -87,6 +87,14 @@ config RESET_SUNXI help This enables the reset driver for Allwinner SoCs. +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 diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index e422a04f7b85..7081f9da2599 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -14,6 +14,7 @@ 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-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o obj-$(CONFIG_RESET_ZX2967) += reset-zx2967.o 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 #include #include +#include #include #include #include @@ -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; } } @@ -302,23 +303,30 @@ 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_release(struct kref *kref) +{ + struct reset_control *rstc = container_of(kref, struct reset_control, + refcnt); + + lockdep_assert_held(&reset_list_mutex); + + module_put(rstc->rcdev->owner); + + list_del(&rstc->list); + kfree(rstc); +} + static void __reset_control_put_internal(struct reset_control *rstc) { lockdep_assert_held(&reset_list_mutex); - if (--rstc->refcnt) - return; - - module_put(rstc->rcdev->owner); - - list_del(&rstc->list); - kfree(rstc); + kref_put(&rstc->refcnt, __reset_control_release); } struct reset_control *__of_reset_control_get(struct device_node *node, @@ -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-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 + * + * 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 +#include +#include +#include +#include +#include +#include + +/** + * 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 "); +MODULE_DESCRIPTION("TI System Control Interface (TI SCI) Reset driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/dt-bindings/reset/altr,rst-mgr-s10.h b/include/dt-bindings/reset/altr,rst-mgr-s10.h new file mode 100644 index 000000000000..7978c21e4fad --- /dev/null +++ b/include/dt-bindings/reset/altr,rst-mgr-s10.h @@ -0,0 +1,108 @@ +/* + * Copyright (C) 2016 Intel Corporation. All rights reserved + * Copyright (C) 2016 Altera Corporation. All rights reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + * + * derived from Steffen Trumtrar's "altr,rst-mgr-a10.h" + */ + +#ifndef _DT_BINDINGS_RESET_ALTR_RST_MGR_S10_H +#define _DT_BINDINGS_RESET_ALTR_RST_MGR_S10_H + +/* MPUMODRST */ +#define CPU0_RESET 0 +#define CPU1_RESET 1 +#define CPU2_RESET 2 +#define CPU3_RESET 3 + +/* PER0MODRST */ +#define EMAC0_RESET 32 +#define EMAC1_RESET 33 +#define EMAC2_RESET 34 +#define USB0_RESET 35 +#define USB1_RESET 36 +#define NAND_RESET 37 +/* 38 is empty */ +#define SDMMC_RESET 39 +#define EMAC0_OCP_RESET 40 +#define EMAC1_OCP_RESET 41 +#define EMAC2_OCP_RESET 42 +#define USB0_OCP_RESET 43 +#define USB1_OCP_RESET 44 +#define NAND_OCP_RESET 45 +/* 46 is empty */ +#define SDMMC_OCP_RESET 47 +#define DMA_RESET 48 +#define SPIM0_RESET 49 +#define SPIM1_RESET 50 +#define SPIS0_RESET 51 +#define SPIS1_RESET 52 +#define DMA_OCP_RESET 53 +#define EMAC_PTP_RESET 54 +/* 55 is empty*/ +#define DMAIF0_RESET 56 +#define DMAIF1_RESET 57 +#define DMAIF2_RESET 58 +#define DMAIF3_RESET 59 +#define DMAIF4_RESET 60 +#define DMAIF5_RESET 61 +#define DMAIF6_RESET 62 +#define DMAIF7_RESET 63 + +/* PER1MODRST */ +#define WATCHDOG0_RESET 64 +#define WATCHDOG1_RESET 65 +#define WATCHDOG2_RESET 66 +#define WATCHDOG3_RESET 67 +#define L4SYSTIMER0_RESET 68 +#define L4SYSTIMER1_RESET 69 +#define SPTIMER0_RESET 70 +#define SPTIMER1_RESET 71 +#define I2C0_RESET 72 +#define I2C1_RESET 73 +#define I2C2_RESET 74 +#define I2C3_RESET 75 +#define I2C4_RESET 76 +/* 77-79 is empty */ +#define UART0_RESET 80 +#define UART1_RESET 81 +/* 82-87 is empty */ +#define GPIO0_RESET 88 +#define GPIO1_RESET 89 + +/* BRGMODRST */ +#define SOC2FPGA_RESET 96 +#define LWHPS2FPGA_RESET 97 +#define FPGA2SOC_RESET 98 +#define F2SSDRAM0_RESET 99 +#define F2SSDRAM1_RESET 100 +#define F2SSDRAM2_RESET 101 +#define DDRSCH_RESET 102 + +/* COLDMODRST */ +#define CPUPO0_RESET 160 +#define CPUPO1_RESET 161 +#define CPUPO2_RESET 162 +#define CPUPO3_RESET 163 +/* 164-167 is empty */ +#define L2_RESET 168 + +/* DBGMODRST */ +#define DBG_RESET 224 +#define CSDAP_RESET 225 + +/* TAPMODRST */ +#define TAP_RESET 256 + +#endif