[PATCHv2 2/2] watchdog: imx2_wdt: Add big-endian support

Xiubo Li
2014-03-26T03:11:24Z

For the platforms that this IP driver now supports:
SoC CPU Watchdog Need 'big-endian'?
------------------------------------------------------
Vybird little little No
LS1 little big Yes
LS2 little little No
IMX+ little little No

So for the LS1 SoCs, we need to do the big endianness converting.

And this will also support the following case, for example:
SoC CPU Watchdog Need 'big-endian'?
------------------------------------------------------
PowerPC big big Yes

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Cc: Guenter Roeck <linux@roeck-us.net>
---
drivers/watchdog/imx2_wdt.c | 40 +++++++++++++++++++++++++++++++---------
1 file changed, 31 insertions(+), 9 deletions(-)

diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index 1795922..32f8874 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -30,6 +30,7 @@
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
@@ -64,9 +65,26 @@ static struct {
void __iomem *base;
unsigned timeout;
unsigned long status;
+ bool big_endian;
struct timer_list timer; /* Pings the watchdog when closed */
} imx2_wdt;

+static inline u16 imx2_wdt_readw(void __iomem *addr)
+{
+ if (imx2_wdt.big_endian)
+ return ioread16be(addr);
+ else
+ return ioread16(addr);
+}
+
+static inline void imx2_wdt_writew(u16 val, void __iomem *addr)
+{
+ if (imx2_wdt.big_endian)
+ iowrite16be(val, addr);
+ else
+ iowrite16(val, addr);
+}
+
static struct miscdevice imx2_wdt_miscdev;

static bool nowayout = WATCHDOG_NOWAYOUT;
@@ -87,7 +105,7 @@ static const struct watchdog_info imx2_wdt_info = {

static inline void imx2_wdt_setup(void)
{
- u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR);
+ u16 val = imx2_wdt_readw(imx2_wdt.base + IMX2_WDT_WCR);

/* Suspend timer in low power mode, write once-only */
val |= IMX2_WDT_WCR_WDZST;
@@ -100,17 +118,17 @@ static inline void imx2_wdt_setup(void)
/* Set the watchdog's Time-Out value */
val |= WDOG_SEC_TO_COUNT(imx2_wdt.timeout);

- __raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
+ imx2_wdt_writew(val, imx2_wdt.base + IMX2_WDT_WCR);

/* enable the watchdog */
val |= IMX2_WDT_WCR_WDE;
- __raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
+ imx2_wdt_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
}

static inline void imx2_wdt_ping(void)
{
- __raw_writew(IMX2_WDT_SEQ1, imx2_wdt.base + IMX2_WDT_WSR);
- __raw_writew(IMX2_WDT_SEQ2, imx2_wdt.base + IMX2_WDT_WSR);
+ imx2_wdt_writew(IMX2_WDT_SEQ1, imx2_wdt.base + IMX2_WDT_WSR);
+ imx2_wdt_writew(IMX2_WDT_SEQ2, imx2_wdt.base + IMX2_WDT_WSR);
}

static void imx2_wdt_timer_ping(unsigned long arg)
@@ -143,12 +161,12 @@ static void imx2_wdt_stop(void)

static void imx2_wdt_set_timeout(int new_timeout)
{
- u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR);
+ u16 val = imx2_wdt_readw(imx2_wdt.base + IMX2_WDT_WCR);

/* set the new timeout value in the WSR */
val &= ~IMX2_WDT_WCR_WT;
val |= WDOG_SEC_TO_COUNT(new_timeout);
- __raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
+ imx2_wdt_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
}

static int imx2_wdt_open(struct inode *inode, struct file *file)
@@ -192,7 +210,7 @@ static long imx2_wdt_ioctl(struct file *file, unsigned int cmd,
return put_user(0, p);

case WDIOC_GETBOOTSTATUS:
- val = __raw_readw(imx2_wdt.base + IMX2_WDT_WRSR);
+ val = imx2_wdt_readw(imx2_wdt.base + IMX2_WDT_WRSR);
new_value = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0;
return put_user(new_value, p);

@@ -257,8 +275,12 @@ static struct miscdevice imx2_wdt_miscdev = {

static int __init imx2_wdt_probe(struct platform_device *pdev)
{
- int ret;
+ struct device_node *np = pdev->dev.of_node;
struct resource *res;
+ int ret;
+
+ if (np)
+ imx2_wdt.big_endian = of_property_read_bool(np, "big-endian");

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
imx2_wdt.base = devm_ioremap_resource(&pdev->dev, res);
--
1.8.4