Added support for brmstb_hwspinlock driver that makes use of the hwspinlock framework. Driver uses SUN_TOP_CTRL_SEMAPHORE_[1:15] registers to implement the hardware semaphore. With this change other brcmstb drivers can use hwspin_trylock() and hwspin_unlock() apis and make use of this hwspinlock framework. Other driver dt nodes just need to use a reference to the &hwspinlock and the lock id they want to use. e.g. hwlocks = <&hwspinlock0 0>;
Signed-off-by: Kamal Dasu <[email protected]> --- drivers/hwspinlock/Kconfig | 11 ++- drivers/hwspinlock/Makefile | 1 + drivers/hwspinlock/brcmstb_hwspinlock.c | 96 +++++++++++++++++++++++++ 3 files changed, 107 insertions(+), 1 deletion(-) create mode 100644 drivers/hwspinlock/brcmstb_hwspinlock.c diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig index 3874d15b0e9b..39797cadfd0b 100644 --- a/drivers/hwspinlock/Kconfig +++ b/drivers/hwspinlock/Kconfig @@ -8,6 +8,16 @@ menuconfig HWSPINLOCK if HWSPINLOCK +config HWSPINLOCK_BRCMSTB + tristate "Broadcom Setttop Hardware Semaphore functionality" + depends on ARCH_BRCMSTB || COMPILE_TEST + help + Broadcom settop hwspinlock driver. + Say y here to support the Broadcom Hardware Semaphore functionality, which + provides a synchronisation mechanism on the SoC. + + If unsure, say N. + config HWSPINLOCK_OMAP tristate "OMAP Hardware Spinlock device" depends on ARCH_OMAP4 || SOC_OMAP5 || SOC_DRA7XX || SOC_AM33XX || SOC_AM43XX || ARCH_K3 || COMPILE_TEST @@ -62,5 +72,4 @@ config HSEM_U8500 SoC. If unsure, say N. - endif # HWSPINLOCK diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile index a0f16c9aaa82..35f2d94d8ba2 100644 --- a/drivers/hwspinlock/Makefile +++ b/drivers/hwspinlock/Makefile @@ -4,6 +4,7 @@ # obj-$(CONFIG_HWSPINLOCK) += hwspinlock_core.o +obj-$(CONFIG_HWSPINLOCK_BRCMSTB) += brcmstb_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_SPRD) += sprd_hwspinlock.o diff --git a/drivers/hwspinlock/brcmstb_hwspinlock.c b/drivers/hwspinlock/brcmstb_hwspinlock.c new file mode 100644 index 000000000000..0b164c57192e --- /dev/null +++ b/drivers/hwspinlock/brcmstb_hwspinlock.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * brcmstb HWSEM driver + * + * Copyright (C) 2025 Broadcom + * + */ + +#include <linux/delay.h> +#include <linux/hwspinlock.h> +#include <linux/io.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include "hwspinlock_internal.h" + +#define BRCMSTB_NUM_SEMAPHORES 16 +#define RESET_SEMAPHORE 0 + +#define HWSPINLOCK_VAL 'L' + +static int brcmstb_hwspinlock_trylock(struct hwspinlock *lock) +{ + void __iomem *lock_addr = (void __iomem *)lock->priv; + + writel(HWSPINLOCK_VAL, lock_addr); + + return (readl(lock_addr) == HWSPINLOCK_VAL); +} + +static void brcmstb_hwspinlock_unlock(struct hwspinlock *lock) +{ + void __iomem *lock_addr = (void __iomem *)lock->priv; + + /* release the lock by writing 0 to it */ + writel(RESET_SEMAPHORE, lock_addr); +} + +static void brcmstb_hwspinlock_relax(struct hwspinlock *lock) +{ + ndelay(50); +} + +static const struct hwspinlock_ops brcmstb_hwspinlock_ops = { + .trylock = brcmstb_hwspinlock_trylock, + .unlock = brcmstb_hwspinlock_unlock, + .relax = brcmstb_hwspinlock_relax, +}; + +static int brcmstb_hwspinlock_probe(struct platform_device *pdev) +{ + struct hwspinlock_device *bank; + struct hwspinlock *hwlock; + void __iomem *io_base; + int i, num_locks = BRCMSTB_NUM_SEMAPHORES; + + io_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(io_base)) { + dev_err(&pdev->dev, "semaphore iobase mapping error\n"); + return PTR_ERR(io_base); + } + + bank = devm_kzalloc(&pdev->dev, struct_size(bank, lock, num_locks), + GFP_KERNEL); + if (!bank) + return -ENOMEM; + + for (i = 0, hwlock = &bank->lock[0]; i < num_locks; i++, hwlock++) + hwlock->priv = (void __iomem *)(io_base + sizeof(u32) * i); + + return devm_hwspin_lock_register(&pdev->dev, bank, + &brcmstb_hwspinlock_ops, + 0, num_locks); +} + +static const struct of_device_id brcmstb_hwspinlock_ids[] = { + { .compatible = "brcm,brcmstb-hwspinlock", }, + { /* end */ }, +}; +MODULE_DEVICE_TABLE(of, brcmstb_hwspinlock_ids); + +static struct platform_driver brcmstb_hwspinlock_driver = { + .probe = brcmstb_hwspinlock_probe, + .driver = { + .name = "brcmstb_hwspinlock", + .of_match_table = brcmstb_hwspinlock_ids, + }, +}; + +module_platform_driver(brcmstb_hwspinlock_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Hardware Spinlock driver for brcmstb"); +MODULE_AUTHOR("Kamal Dasu <[email protected]>"); -- 2.34.1
