[mcs814x] add Moschip MSC814x support

This target currently only supports Moschip's MCS8140 SoC, but support
for other chips in the same family (MCS8142, MCS8144) will be easy to add.

Target support is entirely using Device Tree for probing peripherals.
Drivers support include:
- PCI
- USB 1 & 2
- watchdog
- random number generator
- UART
- timer
- internal Ethernet PHY
- Ethernet MAC core

Support for the following boards is included using Device Tree
- Devolo dLAN USB Extender
- Tigal RBT-832

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@32462 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 207 insertions, 0 deletions

diff --git a/target/linux/mcs814x/files-3.3/drivers/watchdog/mcs814x_wdt.c b/target/linux/mcs814x/files-3.3/drivers/watchdog/mcs814x_wdt.c
new file mode 100644
index 000000000..d2f4c5994
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/drivers/watchdog/mcs814x_wdt.c
@@ -0,0 +1,207 @@
+/*
+ * Moschip MCS814x Watchdog driver
+ *
+ * Copyright (C) 2012, Florian Fainelli <florian@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+
+#define WDT_COUNT	0x00
+#define WDT_CTRL	0x04
+#define  WDT_CTRL_EN	0x1
+
+/* watchdog frequency */
+#define WDT_MAX_VALUE	(0xffffffff)
+
+struct mcs814x_wdt {
+	void __iomem		*regs;
+	spinlock_t		lock;
+	struct watchdog_device	wdt_dev;
+	struct clk		*clk;
+};
+
+static int mcs814x_wdt_start(struct watchdog_device *dev)
+{
+	struct mcs814x_wdt *wdt = watchdog_get_drvdata(dev);
+	u32 reg;
+
+	spin_lock(&wdt->lock);
+	reg = __raw_readl(wdt->regs + WDT_CTRL);
+	reg |= WDT_CTRL_EN;
+	__raw_writel(reg, wdt->regs + WDT_CTRL);
+	spin_unlock(&wdt->lock);
+
+	return 0;
+}
+
+static int mcs814x_wdt_stop(struct watchdog_device *dev)
+{
+	struct mcs814x_wdt *wdt = watchdog_get_drvdata(dev);
+	u32 reg;
+
+	spin_lock(&wdt->lock);
+	reg = __raw_readl(wdt->regs + WDT_CTRL);
+	reg &= ~WDT_CTRL_EN;
+	__raw_writel(reg, wdt->regs + WDT_CTRL);
+	spin_unlock(&wdt->lock);
+
+	return 0;
+}
+
+static int mcs814x_wdt_set_timeout(struct watchdog_device *dev,
+				unsigned int new_timeout)
+{
+	struct mcs814x_wdt *wdt = watchdog_get_drvdata(dev);
+
+	spin_lock(&wdt->lock);
+	/* watchdog counts upward and rollover (0xfffffff -> 0)
+	 * triggers the reboot
+	 */
+	__raw_writel(WDT_MAX_VALUE - (new_timeout * clk_get_rate(wdt->clk)),
+		wdt->regs + WDT_COUNT);
+	spin_unlock(&wdt->lock);
+
+	return 0;
+}
+
+static int mcs814x_wdt_ping(struct watchdog_device *dev)
+{
+	/* restart the watchdog */
+	mcs814x_wdt_stop(dev);
+	mcs814x_wdt_set_timeout(dev, dev->timeout);
+	mcs814x_wdt_start(dev);
+
+	return 0;
+}
+
+static const struct watchdog_info mcs814x_wdt_ident = {
+	.options	= WDIOF_CARDRESET | WDIOF_SETTIMEOUT |
+			  WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
+	.identity	= "MCS814x Watchdog",
+};
+
+static struct watchdog_ops mcs814x_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= mcs814x_wdt_start,
+	.stop		= mcs814x_wdt_stop,
+	.set_timeout	= mcs814x_wdt_set_timeout,
+	.ping		= mcs814x_wdt_ping,
+};
+
+static int __devinit mcs814x_wdt_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct mcs814x_wdt *wdt;
+	int ret;
+	struct clk *clk;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	clk = clk_get(NULL, "wdt");
+	if (IS_ERR_OR_NULL(clk)) {
+		dev_err(&pdev->dev, "failed to get watchdog clock\n");
+		return PTR_ERR(clk);
+	}
+
+	wdt = kzalloc(sizeof(*wdt), GFP_KERNEL);
+	if (!wdt) {
+		ret = -ENOMEM;
+		goto out_clk;
+	}
+
+	spin_lock_init(&wdt->lock);
+	wdt->clk = clk;
+	wdt->wdt_dev.info = &mcs814x_wdt_ident;
+	wdt->wdt_dev.ops = &mcs814x_wdt_ops;
+	wdt->wdt_dev.min_timeout = 1;
+	/* approximately 10995 secs */
+	wdt->wdt_dev.max_timeout = (WDT_MAX_VALUE / clk_get_rate(clk));
+
+	platform_set_drvdata(pdev, wdt);
+
+	/* only ioremap registers, because the register is shared */
+	wdt->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!wdt->regs) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	watchdog_set_drvdata(&wdt->wdt_dev, wdt);
+
+	ret = watchdog_register_device(&wdt->wdt_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "cannot register watchdog: %d\n", ret);
+		goto out;
+	}
+
+	dev_info(&pdev->dev, "registered\n");
+	return 0;
+
+out:
+	platform_set_drvdata(pdev, NULL);
+	kfree(wdt);
+out_clk:
+	clk_put(clk);
+	return ret;
+}
+
+static int __devexit mcs814x_wdt_remove(struct platform_device *pdev)
+{
+	struct mcs814x_wdt *wdt = platform_get_drvdata(pdev);
+
+	clk_put(wdt->clk);
+	watchdog_unregister_device(&wdt->wdt_dev);
+	watchdog_set_drvdata(&wdt->wdt_dev, NULL);
+	kfree(wdt);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static const struct of_device_id mcs814x_wdt_ids[] = {
+	{ .compatible = "moschip,mcs814x-wdt", },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver mcs814x_wdt_driver = {
+	.driver	= {
+		.name	= "mcs814x-wdt",
+		.owner	= THIS_MODULE,
+		.of_match_table = mcs814x_wdt_ids,
+	},
+	.probe		= mcs814x_wdt_probe,
+	.remove		= __devexit_p(mcs814x_wdt_remove),
+};
+
+module_platform_driver(mcs814x_wdt_driver);
+
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("Moschip MCS814x Watchdog driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
+MODULE_ALIAS("platform:mcs814x-wdt");