hwspinlock: qcom: Add support for Qualcomm HW Mutex block

Add driver for Qualcomm Hardware Mutex block found in many Qualcomm
SoCs.

Based on initial effort by Kumar Gala <galak@codeaurora.org>

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Reviewed-by: Andy Gross <agross@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>

diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index 3612cb5b30b206a066c75d835402654cacf7d002..b5b4f52cef7318c377eeb80fc5186778b4c7a2a4 100644 (file)
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -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

diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index 93eb64b664863b58b3cb1fb0c32c5c04ead0dad1..68f95d9a48557fbf64b617d8cb629d6bfe4f1b54 100644 (file)
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -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

diff --git a/drivers/hwspinlock/qcom_hwspinlock.c b/drivers/hwspinlock/qcom_hwspinlock.c
new file mode 100644 (file)
index 0000000..93b62e0
--- /dev/null
+++ b/drivers/hwspinlock/qcom_hwspinlock.c
@@ -0,0 +1,181 @@
+/*
+ * 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");