| Message ID | 1375135257-17222-1-git-send-email-galak@codeaurora.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 07/29/13 15:00, Kumar Gala wrote: > diff --git a/drivers/hwspinlock/msm_hwspinlock.c b/drivers/hwspinlock/msm_hwspinlock.c > new file mode 100644 > index 0000000..dbd9a69 > --- /dev/null > +++ b/drivers/hwspinlock/msm_hwspinlock.c > @@ -0,0 +1,150 @@ > +/* > + * Copyright (c) 2013, The Linux Foundation. All rights reserved. > + * > + * This software is licensed under the terms of the GNU General Public > + * License version 2, as published by the Free Software Foundation, and > + * may be copied, distributed, and modified under those terms. > + * > + * This program is distributed in the hope that 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. > + */ > + > +#include <linux/err.h> > +#include <linux/kernel.h> > +#include <linux/slab.h> > +#include <linux/device.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_device.h> > +#include <linux/hwspinlock.h> > +#include <linux/io.h> > + > +#include "hwspinlock_internal.h" > + > +#define SPINLOCK_ID_APPS_PROC 1 Is this id only for the apps processor? What about hexagon? Does it need a different number? > +#define BASE_ID 0 > + > +static int msm_hwspinlock_trylock(struct hwspinlock *lock) > +{ > + void __iomem *lock_addr = lock->priv; > + > + writel_relaxed(SPINLOCK_ID_APPS_PROC, lock_addr); > + smp_mb(); > + return readl_relaxed(lock_addr) == SPINLOCK_ID_APPS_PROC; > +} > + > +static void msm_hwspinlock_unlock(struct hwspinlock *lock) > +{ > + int lock_owner; This should probably be u32 to be explicit about the size of the register. > + void __iomem *lock_addr = lock->priv; > + > + lock_owner = readl_relaxed(lock_addr); > + if (lock_owner != SPINLOCK_ID_APPS_PROC) { > + pr_err("%s: spinlock not owned by Apps (actual owner is %d)\n", Maybe you should just say "spinlock not owned by us (actual owner is %d)" so that this driver is agnostic to the processor it runs on? > + __func__, lock_owner); > + } > + > + writel_relaxed(0, lock_addr); > + smp_mb(); > +} >
On 8/12/2013 10:35 AM, Stephen Boyd wrote: > On 07/29/13 15:00, Kumar Gala wrote: >> diff --git a/drivers/hwspinlock/msm_hwspinlock.c b/drivers/hwspinlock/msm_hwspinlock.c >> new file mode 100644 >> index 0000000..dbd9a69 >> --- /dev/null >> +++ b/drivers/hwspinlock/msm_hwspinlock.c >> @@ -0,0 +1,150 @@ >> +/* >> + * Copyright (c) 2013, The Linux Foundation. All rights reserved. >> + * >> + * This software is licensed under the terms of the GNU General Public >> + * License version 2, as published by the Free Software Foundation, and >> + * may be copied, distributed, and modified under those terms. >> + * >> + * This program is distributed in the hope that 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. >> + */ >> + >> +#include <linux/err.h> >> +#include <linux/kernel.h> >> +#include <linux/slab.h> >> +#include <linux/device.h> >> +#include <linux/module.h> >> +#include <linux/platform_device.h> >> +#include <linux/of.h> >> +#include <linux/of_address.h> >> +#include <linux/of_device.h> >> +#include <linux/hwspinlock.h> >> +#include <linux/io.h> >> + >> +#include "hwspinlock_internal.h" >> + >> +#define SPINLOCK_ID_APPS_PROC 1 > > Is this id only for the apps processor? What about hexagon? Does it need > a different number? Yes, hexagon would need a different id based on what job that particular hexagon processor is doing. I'm not currently aware of a hexagon usecase, but I believe modifying the DT binding in the future would cover the usecase if it comes up. > >> +#define BASE_ID 0 >> + >> +static int msm_hwspinlock_trylock(struct hwspinlock *lock) >> +{ >> + void __iomem *lock_addr = lock->priv; >> + >> + writel_relaxed(SPINLOCK_ID_APPS_PROC, lock_addr); >> + smp_mb(); >> + return readl_relaxed(lock_addr) == SPINLOCK_ID_APPS_PROC; >> +} >> + >> +static void msm_hwspinlock_unlock(struct hwspinlock *lock) >> +{ >> + int lock_owner; > > This should probably be u32 to be explicit about the size of the register. > >> + void __iomem *lock_addr = lock->priv; >> + >> + lock_owner = readl_relaxed(lock_addr); >> + if (lock_owner != SPINLOCK_ID_APPS_PROC) { >> + pr_err("%s: spinlock not owned by Apps (actual owner is %d)\n", > > Maybe you should just say "spinlock not owned by us (actual owner is > %d)" so that this driver is agnostic to the processor it runs on? > >> + __func__, lock_owner); >> + } >> + >> + writel_relaxed(0, lock_addr); >> + smp_mb(); >> +} >> > Jeffrey Hugo
diff --git a/Documentation/devicetree/bindings/arm/msm/tcsr-mutex.txt b/Documentation/devicetree/bindings/arm/msm/tcsr-mutex.txt new file mode 100644 index 0000000..ddd6889 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/msm/tcsr-mutex.txt @@ -0,0 +1,20 @@ +Qualcomm MSM Hardware Mutex Block: + +The hardware block provides mutexes utilized between different processors +on the SoC as part of the communication protocol used by these processors. + +Required properties: +- compatible: should be "qcom,tcsr-mutex" +- reg: Should contain registers location and length of mutex registers +- reg-names: + "mutex-base" - string to identify mutex registers +- qcom,num-locks: the number of locks/mutexes supported + +Example: + + qcom,tcsr-mutex@fd484000 { + compatible = "qcom,tcsr-mutex"; + reg = <0xfd484000 0x1000>; + reg-names = "mutex-base"; + qcom,num-locks = <32>; + }; diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig index 70637d2..192e939 100644 --- a/drivers/hwspinlock/Kconfig +++ b/drivers/hwspinlock/Kconfig @@ -8,6 +8,17 @@ config HWSPINLOCK menu "Hardware Spinlock drivers" +config HWSPINLOCK_MSM + tristate "MSM Hardware Spinlock device" + depends on ARCH_MSM + select HWSPINLOCK + help + Say y here to support the MSM Hardware Mutex functionality, which + provides a synchronisation mechanism for the various processors on + the SoC. + + If unsure, say N. + config HWSPINLOCK_OMAP tristate "OMAP Hardware Spinlock device" depends on ARCH_OMAP4 || SOC_OMAP5 diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile index 93eb64b..4074c56 100644 --- a/drivers/hwspinlock/Makefile +++ b/drivers/hwspinlock/Makefile @@ -3,5 +3,6 @@ # obj-$(CONFIG_HWSPINLOCK) += hwspinlock_core.o +obj-$(CONFIG_HWSPINLOCK_MSM) += msm_hwspinlock.o obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o diff --git a/drivers/hwspinlock/msm_hwspinlock.c b/drivers/hwspinlock/msm_hwspinlock.c new file mode 100644 index 0000000..dbd9a69 --- /dev/null +++ b/drivers/hwspinlock/msm_hwspinlock.c @@ -0,0 +1,150 @@ +/* + * Copyright (c) 2013, The Linux Foundation. All rights reserved. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that 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. + */ + +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/hwspinlock.h> +#include <linux/io.h> + +#include "hwspinlock_internal.h" + +#define SPINLOCK_ID_APPS_PROC 1 +#define BASE_ID 0 + +static int msm_hwspinlock_trylock(struct hwspinlock *lock) +{ + void __iomem *lock_addr = lock->priv; + + writel_relaxed(SPINLOCK_ID_APPS_PROC, lock_addr); + smp_mb(); + return readl_relaxed(lock_addr) == SPINLOCK_ID_APPS_PROC; +} + +static void msm_hwspinlock_unlock(struct hwspinlock *lock) +{ + int lock_owner; + void __iomem *lock_addr = lock->priv; + + lock_owner = readl_relaxed(lock_addr); + if (lock_owner != SPINLOCK_ID_APPS_PROC) { + pr_err("%s: spinlock not owned by Apps (actual owner is %d)\n", + __func__, lock_owner); + } + + writel_relaxed(0, lock_addr); + smp_mb(); +} + +static const struct hwspinlock_ops msm_hwspinlock_ops = { + .trylock = msm_hwspinlock_trylock, + .unlock = msm_hwspinlock_unlock, +}; + +static const struct of_device_id msm_hwspinlock_of_match[] = { + { + .compatible = "qcom,tcsr-mutex", + .data = (void *)0x80, /* register stride */ + }, + { }, +}; + +static int msm_hwspinlock_probe(struct platform_device *pdev) +{ + int ret, i, stride; + size_t array_size; + u32 num_locks; + struct hwspinlock_device *bank; + struct hwspinlock *hwlock; + struct resource *res; + void __iomem *iobase; + struct device_node *node = pdev->dev.of_node; + const struct of_device_id *match; + + match = of_match_device(msm_hwspinlock_of_match, &pdev->dev); + if (!match) + return -EINVAL; + + ret = of_property_read_u32(node, "qcom,num-locks", &num_locks); + if (ret || num_locks == 0) + return -ENODEV; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mutex-base"); + iobase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(iobase)) + return PTR_ERR(iobase); + + array_size = num_locks * sizeof(*hwlock); + bank = devm_kzalloc(&pdev->dev, sizeof(*bank) + array_size, GFP_KERNEL); + if (!bank) + return -ENOMEM; + + platform_set_drvdata(pdev, bank); + + stride = (int)match->data; + for (i = 0, hwlock = &bank->lock[0]; i < num_locks; i++, hwlock++) + hwlock->priv = iobase + i * stride; + + ret = hwspin_lock_register(bank, &pdev->dev, &msm_hwspinlock_ops, + BASE_ID, num_locks); + return ret; +} + +static int msm_hwspinlock_remove(struct platform_device *pdev) +{ + struct hwspinlock_device *bank = platform_get_drvdata(pdev); + int ret; + + ret = hwspin_lock_unregister(bank); + if (ret) { + dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret); + return ret; + } + + return 0; +} + +static struct platform_driver msm_hwspinlock_driver = { + .probe = msm_hwspinlock_probe, + .remove = msm_hwspinlock_remove, + .driver = { + .name = "msm_hwspinlock", + .owner = THIS_MODULE, + .of_match_table = msm_hwspinlock_of_match, + }, +}; + +static int __init msm_hwspinlock_init(void) +{ + return platform_driver_register(&msm_hwspinlock_driver); +} +/* board init code might need to reserve hwspinlocks for predefined purposes */ +postcore_initcall(msm_hwspinlock_init); + +static void __exit msm_hwspinlock_exit(void) +{ + platform_driver_unregister(&msm_hwspinlock_driver); +} +module_exit(msm_hwspinlock_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Hardware spinlock driver for MSM"); +MODULE_AUTHOR("Kumar Gala <galak@codeaurora.org>"); +MODULE_AUTHOR("Jeffrey Hugo <jhugo@codeaurora.org>"); +MODULE_AUTHOR("Eric Holmberg <eholmber@codeaurora.org>");
Add driver for Qualcomm MSM Hardware Mutex block that exists on newer MSM SoC (MSM8974, etc). CC: Jeffrey Hugo <jhugo@codeaurora.org> CC: Eric Holmberg <eholmber@codeaurora.org> Signed-off-by: Kumar Gala <galak@codeaurora.org> --- v2: * Fixed init of stride * Dealt with a number of comments from Stephen Boyd: - use of <linux/io.h> instead of <asm/io.h> - declaring msm_hwspinlock_of_match once & as const - drop unneccessary () in an if statement - style cleanup to have devm_kzalloc on one line TODO: * feedback from Ohad on device tree binding location & hw-mutex name * comments from Eric/Jeff on use of mb() .../devicetree/bindings/arm/msm/tcsr-mutex.txt | 20 +++ drivers/hwspinlock/Kconfig | 11 ++ drivers/hwspinlock/Makefile | 1 + drivers/hwspinlock/msm_hwspinlock.c | 150 +++++++++++++++++++++ 4 files changed, 182 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/msm/tcsr-mutex.txt create mode 100644 drivers/hwspinlock/msm_hwspinlock.c