1 files changed, 265 insertions, 0 deletions
diff --git a/drivers/hwspinlock/sci_hwspinlock.c b/drivers/hwspinlock/sci_hwspinlock.c
new file mode 100644
index 00000000..9873aa25
--- /dev/null
+++ b/drivers/hwspinlock/sci_hwspinlock.c
@@ -0,0 +1,265 @@
+/*
+ * SCI hardware spinlock driver
+ *
+ * Copyright (C) 2012 Spreadtrum  - http://www.spreadtrum.com
+ * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Contact: steve.zhan <steve.zhan@spreadtrum.com>
+ *        
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/bitops.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/hwspinlock.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <soc/sprd/sci.h>
+#include <soc/sprd/sci_glb_regs.h>
+#include <soc/sprd/arch_lock.h>
+
+#include "hwspinlock_internal.h"
+
+
+#define HWSPINLOCK_ENABLE_CLEAR		(0x454e434c)
+
+#define HWSPINLOCK_CLEAR		(0x0)
+#define HWSPINLOCK_TTLSTS		(0x4)
+#define HWSPINLOCK_DTLSTL		(0x8)
+#define HWSPINLOCK_CLEAREN		(0xc)
+
+#define HWSPINLOCK_TOKEN_V0(_X_)	(0x80 + 0x4*(_X_))
+#define HWSPINLOCK_TOKEN_V1(_X_)	(0x800 + 0x4*(_X_))
+
+#define THIS_PROCESSOR_KEY	(HWSPINLOCK_WRITE_KEY)	/*first processor */
+static void __iomem *hwspinlock_base;
+static int hwspinlock_exist_cnt = 0;
+
+#define SPINLOCKS_BUSY()	(readl(hwspinlock_base + HWSPINLOCK_TTLSTS))
+#define SPINLOCKS_DETAIL_STATUS(_X_)	(_X_ = readl(hwspinlock_base + HWSPINLOCK_DTLSTL))
+#define SPINLOCKS_ENABLE_CLEAR()	writel(HWSPINLOCK_ENABLE_CLEAR,hwspinlock_base + HWSPINLOCK_CLEAREN)
+#define SPINLOCKS_DISABLE_CLEAR()	writel(~HWSPINLOCK_ENABLE_CLEAR, hwspinlock_base + HWSPINLOCK_CLEAREN)
+
+__used static int hwspinlock_isbusy(unsigned int lockid)
+{
+	unsigned int status = 0;
+	SPINLOCKS_DETAIL_STATUS(status);
+	return ((status & (1 << lockid)) ? 1 : 0);
+}
+
+__used static int hwspinlocks_isbusy(void)
+{
+	return ((SPINLOCKS_BUSY())? 1 : 0);
+}
+
+__used static void hwspinlock_clear(unsigned int lockid)
+{
+	/*setting the abnormal clear bit to 1 makes the corresponding
+	 *lock to Not Taken state
+	 */
+	SPINLOCKS_ENABLE_CLEAR();
+	writel(1 << lockid, hwspinlock_base + HWSPINLOCK_CLEAR);
+	SPINLOCKS_DISABLE_CLEAR();
+}
+
+__used static void hwspinlock_clear_all(void)
+{
+	/*clear all the locks
+	 */
+	unsigned int lockid = 0;
+	SPINLOCKS_ENABLE_CLEAR();
+	do {
+		writel(1 << lockid, hwspinlock_base + HWSPINLOCK_CLEAR);
+	} while (lockid++ < HWSPINLOCK_ID_TOTAL_NUMS);
+	SPINLOCKS_DISABLE_CLEAR();
+}
+
+static unsigned int do_lock_key(struct hwspinlock *lock)
+{
+	unsigned int key = THIS_PROCESSOR_KEY;
+	return key;
+}
+
+static int __hwspinlock_trylock(struct hwspinlock *lock)
+{
+	void __iomem *addr = lock->priv;
+
+	if (hwspinlock_vid == 0x100 || hwspinlock_vid == 0x200) {
+		if (!readl(addr))
+			goto __locked;
+	} else {
+		unsigned int key = do_lock_key(lock);
+		if (!(key ^ HWSPINLOCK_NOTTAKEN_V0))
+			BUG_ON(1);
+		if (HWSPINLOCK_NOTTAKEN_V0 == readl(addr)) {
+			writel(key, addr);
+			if (key == readl(addr))
+				goto __locked;
+		}
+	}
+	return 0;
+
+__locked:
+	RECORD_HWLOCKS_STATUS_LOCK(hwlock_to_id(lock));
+	return 1;
+}
+
+static void __hwspinlock_unlock(struct hwspinlock *lock)
+{
+	void __iomem *lock_addr = lock->priv;
+	int unlock_key = 0;
+
+	if (hwspinlock_vid == 0x100 || hwspinlock_vid == 0x200) {
+		unlock_key = HWSPINLOCK_NOTTAKEN_V1;
+	} else {
+		unlock_key = HWSPINLOCK_NOTTAKEN_V0;
+		if (!(readl(lock_addr) ^ unlock_key))
+			BUG_ON(1);
+	}
+	RECORD_HWLOCKS_STATUS_UNLOCK(hwlock_to_id(lock));
+	writel(unlock_key, lock_addr);
+}
+
+/*
+ * relax the  interconnect while spinning on it.
+ *
+ * The specs recommended that the retry delay time will be
+ * just over half of the time that a requester would be
+ * expected to hold the lock.
+ *
+ * The number below is taken from an hardware specs example,
+ * obviously it is somewhat arbitrary.
+ */
+static void __hwspinlock_relax(struct hwspinlock *lock)
+{
+	ndelay(10);
+}
+
+static const struct hwspinlock_ops sci_hwspinlock_ops = {
+	.trylock = __hwspinlock_trylock,
+	.unlock = __hwspinlock_unlock,
+	.relax = __hwspinlock_relax,
+};
+
+static int sci_hwspinlock_probe(struct platform_device *pdev)
+{
+	struct hwspinlock_device *bank;
+	struct hwspinlock *hwlock;
+	int i, ret, num_locks;
+
+	pdev->id = of_alias_get_id(pdev->dev.of_node, "hwspinlock");
+	if(pdev->id == 0)
+		return 0;
+	__hwspinlock_init();
+
+	/*each group have 32 locks*/
+	num_locks = 32;
+	hwspinlock_base = (void __iomem *)(pdev->id == 0 ? SPRD_HWSPINLOCK0_BASE : SPRD_HWSPINLOCK1_BASE);
+	hwspinlock_vid = __raw_readl(hwspinlock_base + 0xffc);
+
+	bank = kzalloc(sizeof(*bank) + num_locks * sizeof(*hwlock), GFP_KERNEL);
+	if (!bank) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	platform_set_drvdata(pdev, bank);
+
+	for (i = 0, hwlock = &bank->lock[0]; i < num_locks; i++, hwlock++) {
+		if (hwspinlock_vid == 0x100 || hwspinlock_vid == 0x200)
+			hwlock->priv = (void __iomem *)(hwspinlock_base + HWSPINLOCK_TOKEN_V1(i));
+		else
+			hwlock->priv = (void __iomem *)(hwspinlock_base + HWSPINLOCK_TOKEN_V0(i));
+	}
+	/*
+	 * runtime PM will make sure the clock of this module is
+	 * enabled if at least one lock is requested
+	 */
+	pm_runtime_enable(&pdev->dev);
+
+	ret = hwspin_lock_register(bank, &pdev->dev, &sci_hwspinlock_ops,
+				   hwspinlock_exist_cnt, num_locks);
+
+	if (ret)
+		goto reg_fail;
+
+	hwspinlock_exist_cnt += num_locks;
+
+	printk("sci_hwspinlock_probe ok: hwspinlock name = %s, hwspinlock_vid = 0x%x, add num_locks = %d\n",
+	       pdev->name,hwspinlock_vid,num_locks);
+
+	return 0;
+
+reg_fail:
+	pm_runtime_disable(&pdev->dev);
+	kfree(bank);
+exit:
+	return ret;
+}
+
+static int sci_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);
+	kfree(bank);
+
+	return 0;
+}
+
+static const struct of_device_id sprd_hwspinlock_of_match[] = {
+	{ .compatible = "sprd,sprd-hwspinlock", },
+	{ /* sentinel */ }
+};
+
+static struct platform_driver sci_hwspinlock_driver = {
+	.probe = sci_hwspinlock_probe,
+	.remove = sci_hwspinlock_remove,
+	.driver = {
+		.name = "sci_hwspinlock",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
+	},
+};
+
+static int __init sci_hwspinlock_init(void)
+{
+	return platform_driver_register(&sci_hwspinlock_driver);
+}
+
+/* board init code might need to reserve hwspinlocks for predefined purposes */
+postcore_initcall(sci_hwspinlock_init);
+
+static void __exit sci_hwspinlock_exit(void)
+{
+	platform_driver_unregister(&sci_hwspinlock_driver);
+}
+
+module_exit(sci_hwspinlock_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
+MODULE_AUTHOR("steve.zhan <steve.zhan@spreadtrum.com>");