From 6c9e3e80c526155b14c6af6f55653677707c822b Mon Sep 17 00:00:00 2001 From: Benjamin Gaignard Date: Wed, 14 Nov 2018 10:00:24 +0100 Subject: [PATCH 1/3] dt-bindings: hwlock: Document STM32 hwspinlock bindings Add bindings for STM32 hardware spinlock device Reviewed-by: Rob Herring Signed-off-by: Benjamin Gaignard Signed-off-by: Benjamin Gaignard Signed-off-by: Bjorn Andersson --- .../bindings/hwlock/st,stm32-hwspinlock.txt | 23 +++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt diff --git a/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt new file mode 100644 index 000000000000..adf4f000ea3d --- /dev/null +++ b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt @@ -0,0 +1,23 @@ +STM32 Hardware Spinlock Device Binding +------------------------------------- + +Required properties : +- compatible : should be "st,stm32-hwspinlock". +- reg : the register address of hwspinlock. +- #hwlock-cells : hwlock users only use the hwlock id to represent a specific + hwlock, so the number of cells should be <1> here. +- clock-names : Must contain "hsem". +- clocks : Must contain a phandle entry for the clock in clock-names, see the + common clock bindings. + +Please look at the generic hwlock binding for usage information for consumers, +"Documentation/devicetree/bindings/hwlock/hwlock.txt" + +Example of hwlock provider: + hwspinlock@4c000000 { + compatible = "st,stm32-hwspinlock"; + #hwlock-cells = <1>; + reg = <0x4c000000 0x400>; + clocks = <&rcc HSEM>; + clock-names = "hsem"; + }; From f24fcff1d267da08c4bbb3869e7f4b36ce916b76 Mon Sep 17 00:00:00 2001 From: Benjamin Gaignard Date: Wed, 14 Nov 2018 10:00:25 +0100 Subject: [PATCH 2/3] hwspinlock: add STM32 hwspinlock device This patch adds support of hardware semaphores for stm32mp1 SoC. The hardware block provides 32 semaphores. Signed-off-by: Benjamin Gaignard Signed-off-by: Benjamin Gaignard Signed-off-by: Bjorn Andersson --- drivers/hwspinlock/Kconfig | 9 ++ drivers/hwspinlock/Makefile | 1 + drivers/hwspinlock/stm32_hwspinlock.c | 156 ++++++++++++++++++++++++++ 3 files changed, 166 insertions(+) create mode 100644 drivers/hwspinlock/stm32_hwspinlock.c diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig index e895d29500ee..7869c67e5b6b 100644 --- a/drivers/hwspinlock/Kconfig +++ b/drivers/hwspinlock/Kconfig @@ -49,6 +49,15 @@ config HWSPINLOCK_SPRD If unsure, say N. +config HWSPINLOCK_STM32 + tristate "STM32 Hardware Spinlock device" + depends on MACH_STM32MP157 + depends on HWSPINLOCK + help + Say y here to support the STM32 Hardware Spinlock device. + + If unsure, say N. + config HSEM_U8500 tristate "STE Hardware Semaphore functionality" depends on HWSPINLOCK diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile index b87c01a506a4..ed053e3f02be 100644 --- a/drivers/hwspinlock/Makefile +++ b/drivers/hwspinlock/Makefile @@ -8,4 +8,5 @@ obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_SIRF) += sirf_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_SPRD) += sprd_hwspinlock.o +obj-$(CONFIG_HWSPINLOCK_STM32) += stm32_hwspinlock.o obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c new file mode 100644 index 000000000000..34a8e009dc93 --- /dev/null +++ b/drivers/hwspinlock/stm32_hwspinlock.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) STMicroelectronics SA 2018 + * Author: Benjamin Gaignard for STMicroelectronics. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "hwspinlock_internal.h" + +#define STM32_MUTEX_COREID BIT(8) +#define STM32_MUTEX_LOCK_BIT BIT(31) +#define STM32_MUTEX_NUM_LOCKS 32 + +struct stm32_hwspinlock { + struct clk *clk; + struct hwspinlock_device bank; +}; + +static int stm32_hwspinlock_trylock(struct hwspinlock *lock) +{ + void __iomem *lock_addr = lock->priv; + u32 status; + + writel(STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID, lock_addr); + status = readl(lock_addr); + + return status == (STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID); +} + +static void stm32_hwspinlock_unlock(struct hwspinlock *lock) +{ + void __iomem *lock_addr = lock->priv; + + writel(STM32_MUTEX_COREID, lock_addr); +} + +static const struct hwspinlock_ops stm32_hwspinlock_ops = { + .trylock = stm32_hwspinlock_trylock, + .unlock = stm32_hwspinlock_unlock, +}; + +static int stm32_hwspinlock_probe(struct platform_device *pdev) +{ + struct stm32_hwspinlock *hw; + void __iomem *io_base; + struct resource *res; + size_t array_size; + int i, ret; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + io_base = devm_ioremap_resource(&pdev->dev, res); + if (!io_base) + return -ENOMEM; + + array_size = STM32_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock); + hw = devm_kzalloc(&pdev->dev, sizeof(*hw) + array_size, GFP_KERNEL); + if (!hw) + return -ENOMEM; + + hw->clk = devm_clk_get(&pdev->dev, "hsem"); + if (IS_ERR(hw->clk)) + return PTR_ERR(hw->clk); + + for (i = 0; i < STM32_MUTEX_NUM_LOCKS; i++) + hw->bank.lock[i].priv = io_base + i * sizeof(u32); + + platform_set_drvdata(pdev, hw); + pm_runtime_enable(&pdev->dev); + + ret = hwspin_lock_register(&hw->bank, &pdev->dev, &stm32_hwspinlock_ops, + 0, STM32_MUTEX_NUM_LOCKS); + + if (ret) + pm_runtime_disable(&pdev->dev); + + return ret; +} + +static int stm32_hwspinlock_remove(struct platform_device *pdev) +{ + struct stm32_hwspinlock *hw = platform_get_drvdata(pdev); + int ret; + + ret = hwspin_lock_unregister(&hw->bank); + if (ret) + dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret); + + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static int __maybe_unused stm32_hwspinlock_runtime_suspend(struct device *dev) +{ + struct stm32_hwspinlock *hw = dev_get_drvdata(dev); + + clk_disable_unprepare(hw->clk); + + return 0; +} + +static int __maybe_unused stm32_hwspinlock_runtime_resume(struct device *dev) +{ + struct stm32_hwspinlock *hw = dev_get_drvdata(dev); + + clk_prepare_enable(hw->clk); + + return 0; +} + +static const struct dev_pm_ops stm32_hwspinlock_pm_ops = { + SET_RUNTIME_PM_OPS(stm32_hwspinlock_runtime_suspend, + stm32_hwspinlock_runtime_resume, + NULL) +}; + +static const struct of_device_id stm32_hwpinlock_ids[] = { + { .compatible = "st,stm32-hwspinlock", }, + {}, +}; +MODULE_DEVICE_TABLE(of, stm32_hwpinlock_ids); + +static struct platform_driver stm32_hwspinlock_driver = { + .probe = stm32_hwspinlock_probe, + .remove = stm32_hwspinlock_remove, + .driver = { + .name = "stm32_hwspinlock", + .of_match_table = stm32_hwpinlock_ids, + .pm = &stm32_hwspinlock_pm_ops, + }, +}; + +static int __init stm32_hwspinlock_init(void) +{ + return platform_driver_register(&stm32_hwspinlock_driver); +} +/* board init code might need to reserve hwspinlocks for predefined purposes */ +postcore_initcall(stm32_hwspinlock_init); + +static void __exit stm32_hwspinlock_exit(void) +{ + platform_driver_unregister(&stm32_hwspinlock_driver); +} +module_exit(stm32_hwspinlock_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Hardware spinlock driver for STM32 SoCs"); +MODULE_AUTHOR("Benjamin Gaignard "); From 4d5a91fd1f42a821d14b92b082b8e71be9911ba5 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Thu, 3 Jan 2019 07:02:30 +0000 Subject: [PATCH 3/3] hwspinlock: fix return value check in stm32_hwspinlock_probe() In case of error, the function devm_ioremap_resource() returns ERR_PTR() and never returns NULL. The NULL test in the return value check should be replaced with IS_ERR(). Fixes: f24fcff1d267 ("hwspinlock: add STM32 hwspinlock device") Acked-by: Benjamin Gaignard Signed-off-by: Wei Yongjun Signed-off-by: Bjorn Andersson --- drivers/hwspinlock/stm32_hwspinlock.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c index 34a8e009dc93..441839288893 100644 --- a/drivers/hwspinlock/stm32_hwspinlock.c +++ b/drivers/hwspinlock/stm32_hwspinlock.c @@ -57,8 +57,8 @@ static int stm32_hwspinlock_probe(struct platform_device *pdev) res = platform_get_resource(pdev, IORESOURCE_MEM, 0); io_base = devm_ioremap_resource(&pdev->dev, res); - if (!io_base) - return -ENOMEM; + if (IS_ERR(io_base)) + return PTR_ERR(io_base); array_size = STM32_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock); hw = devm_kzalloc(&pdev->dev, sizeof(*hw) + array_size, GFP_KERNEL);