hwspinlock: qcom: Add support for Qualcomm HW Mutex block (19a0f612) · Commits · e / devices / android_kernel_samsung_universal8895

drivers/hwspinlock/Kconfig

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Original line number	Diff line number	Diff line
		@@ -18,6 +18,18 @@ config HWSPINLOCK_OMAP

		If unsure, say N.

		config HWSPINLOCK_QCOM
		tristate "Qualcomm Hardware Spinlock device"
		depends on ARCH_QCOM
		select HWSPINLOCK
		select MFD_SYSCON
		help
		Say y here to support the Qualcomm Hardware Mutex functionality, which
		provides a synchronisation mechanism for the various processors on
		the SoC.

		If unsure, say N.

		config HSEM_U8500
		tristate "STE Hardware Semaphore functionality"
		depends on ARCH_U8500

drivers/hwspinlock/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -4,4 +4,5 @@

		obj-$(CONFIG_HWSPINLOCK) += hwspinlock_core.o
		obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o
		obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o
		obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o

drivers/hwspinlock/qcom_hwspinlock.c

0 → 100644

+181 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (c) 2013, The Linux Foundation. All rights reserved.
		* Copyright (c) 2015, Sony Mobile Communications AB
		*
		* 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/hwspinlock.h>
		#include <linux/io.h>
		#include <linux/kernel.h>
		#include <linux/mfd/syscon.h>
		#include <linux/module.h>
		#include <linux/of.h>
		#include <linux/of_device.h>
		#include <linux/platform_device.h>
		#include <linux/pm_runtime.h>
		#include <linux/regmap.h>

		#include "hwspinlock_internal.h"

		#define QCOM_MUTEX_APPS_PROC_ID 1
		#define QCOM_MUTEX_NUM_LOCKS 32

		static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
		{
		struct regmap_field *field = lock->priv;
		u32 lock_owner;
		int ret;

		ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);
		if (ret)
		return ret;

		ret = regmap_field_read(field, &lock_owner);
		if (ret)
		return ret;

		return lock_owner == QCOM_MUTEX_APPS_PROC_ID;
		}

		static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
		{
		struct regmap_field *field = lock->priv;
		u32 lock_owner;
		int ret;

		ret = regmap_field_read(field, &lock_owner);
		if (ret) {
		pr_err("%s: unable to query spinlock owner\n", __func__);
		return;
		}

		if (lock_owner != QCOM_MUTEX_APPS_PROC_ID) {
		pr_err("%s: spinlock not owned by us (actual owner is %d)\n",
		__func__, lock_owner);
		}

		ret = regmap_field_write(field, 0);
		if (ret)
		pr_err("%s: failed to unlock spinlock\n", __func__);
		}

		static const struct hwspinlock_ops qcom_hwspinlock_ops = {
		.trylock = qcom_hwspinlock_trylock,
		.unlock = qcom_hwspinlock_unlock,
		};

		static const struct of_device_id qcom_hwspinlock_of_match[] = {
		{ .compatible = "qcom,sfpb-mutex" },
		{ .compatible = "qcom,tcsr-mutex" },
		{ }
		};
		MODULE_DEVICE_TABLE(of, qcom_hwspinlock_of_match);

		static int qcom_hwspinlock_probe(struct platform_device *pdev)
		{
		struct hwspinlock_device *bank;
		struct device_node *syscon;
		struct reg_field field;
		struct regmap *regmap;
		size_t array_size;
		u32 stride;
		u32 base;
		int ret;
		int i;

		syscon = of_parse_phandle(pdev->dev.of_node, "syscon", 0);
		if (!syscon) {
		dev_err(&pdev->dev, "no syscon property\n");
		return -ENODEV;
		}

		regmap = syscon_node_to_regmap(syscon);
		if (IS_ERR(regmap))
		return PTR_ERR(regmap);

		ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 1, &base);
		if (ret < 0) {
		dev_err(&pdev->dev, "no offset in syscon\n");
		return -EINVAL;
		}

		ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 2, &stride);
		if (ret < 0) {
		dev_err(&pdev->dev, "no stride syscon\n");
		return -EINVAL;
		}

		array_size = QCOM_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);
		bank = devm_kzalloc(&pdev->dev, sizeof(*bank) + array_size, GFP_KERNEL);
		if (!bank)
		return -ENOMEM;

		platform_set_drvdata(pdev, bank);

		for (i = 0; i < QCOM_MUTEX_NUM_LOCKS; i++) {
		field.reg = base + i * stride;
		field.lsb = 0;
		field.msb = 32;

		bank->lock[i].priv = devm_regmap_field_alloc(&pdev->dev,
		regmap, field);
		}

		pm_runtime_enable(&pdev->dev);

		ret = hwspin_lock_register(bank, &pdev->dev, &qcom_hwspinlock_ops,
		0, QCOM_MUTEX_NUM_LOCKS);
		if (ret)
		pm_runtime_disable(&pdev->dev);

		return ret;
		}

		static int qcom_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;
		}

		pm_runtime_disable(&pdev->dev);

		return 0;
		}

		static struct platform_driver qcom_hwspinlock_driver = {
		.probe = qcom_hwspinlock_probe,
		.remove = qcom_hwspinlock_remove,
		.driver = {
		.name = "qcom_hwspinlock",
		.of_match_table = qcom_hwspinlock_of_match,
		},
		};

		static int __init qcom_hwspinlock_init(void)
		{
		return platform_driver_register(&qcom_hwspinlock_driver);
		}
		/* board init code might need to reserve hwspinlocks for predefined purposes */
		postcore_initcall(qcom_hwspinlock_init);

		static void __exit qcom_hwspinlock_exit(void)
		{
		platform_driver_unregister(&qcom_hwspinlock_driver);
		}
		module_exit(qcom_hwspinlock_exit);

		MODULE_LICENSE("GPL v2");
		MODULE_DESCRIPTION("Hardware spinlock driver for Qualcomm SoCs");