From: Hauke Mehrtens hauke@hauke-m.de
[ Upstream commit 1f59f8aff98f200af7a6882184add7b85f5da741 ]
Some of the names of the bits were confusing to me. Now the bits share the same prefix as the register they are set on.
The LTQ_WDT_CR_PWL register (bits 26:25) is the pre warning limit and it does not turn anything on. It has 4 possible divers 1/2, 1/4, 1/8 and 1/16, this drivers only uses 1/16. The LTQ_WDT_CR_CLKDIV register bits(25:24) is only configuring a clock divers and do not turn any thing on too, all possible values are valid dividers. Using the LTQ_WDT_SR prefix is also wrong these bits are used in the LTQ_WDT_CR registers, SR is the status register which is read only.
This uses GENMASK where it is a mask and it uses shifts when a value is written to some bits.
Signed-off-by: Hauke Mehrtens hauke@hauke-m.de Reviewed-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Wim Van Sebroeck wim@linux-watchdog.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/watchdog/lantiq_wdt.c | 36 ++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-)
diff --git a/drivers/watchdog/lantiq_wdt.c b/drivers/watchdog/lantiq_wdt.c index 582f2fa1b8d9..6ab14bd9c1e4 100644 --- a/drivers/watchdog/lantiq_wdt.c +++ b/drivers/watchdog/lantiq_wdt.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <linux/fs.h> #include <linux/miscdevice.h> +#include <linux/bitops.h> #include <linux/watchdog.h> #include <linux/of_platform.h> #include <linux/uaccess.h> @@ -28,18 +29,19 @@ * essentially the following two magic passwords need to be written to allow * IO access to the WDT core */ -#define LTQ_WDT_PW1 0x00BE0000 -#define LTQ_WDT_PW2 0x00DC0000 +#define LTQ_WDT_CR_PW1 0x00BE0000 +#define LTQ_WDT_CR_PW2 0x00DC0000 + +#define LTQ_WDT_CR 0x0 /* watchdog control register */ +#define LTQ_WDT_CR_GEN BIT(31) /* enable bit */ +/* Pre-warning limit set to 1/16 of max WDT period */ +#define LTQ_WDT_CR_PWL (0x3 << 26) +/* set clock divider to 0x40000 */ +#define LTQ_WDT_CR_CLKDIV (0x3 << 24) +#define LTQ_WDT_CR_PW_MASK GENMASK(23, 16) /* Password field */ +#define LTQ_WDT_CR_MAX_TIMEOUT ((1 << 16) - 1) /* The reload field is 16 bit */
-#define LTQ_WDT_CR 0x0 /* watchdog control register */ -#define LTQ_WDT_SR 0x8 /* watchdog status register */ - -#define LTQ_WDT_SR_EN (0x1 << 31) /* enable bit */ -#define LTQ_WDT_SR_PWD (0x3 << 26) /* turn on power */ -#define LTQ_WDT_SR_CLKDIV (0x3 << 24) /* turn on clock and set */ - /* divider to 0x40000 */ #define LTQ_WDT_DIVIDER 0x40000 -#define LTQ_MAX_TIMEOUT ((1 << 16) - 1) /* the reload field is 16 bit */
static bool nowayout = WATCHDOG_NOWAYOUT;
@@ -56,26 +58,26 @@ ltq_wdt_enable(void) { unsigned long int timeout = ltq_wdt_timeout * (ltq_io_region_clk_rate / LTQ_WDT_DIVIDER) + 0x1000; - if (timeout > LTQ_MAX_TIMEOUT) - timeout = LTQ_MAX_TIMEOUT; + if (timeout > LTQ_WDT_CR_MAX_TIMEOUT) + timeout = LTQ_WDT_CR_MAX_TIMEOUT;
/* write the first password magic */ - ltq_w32(LTQ_WDT_PW1, ltq_wdt_membase + LTQ_WDT_CR); + ltq_w32(LTQ_WDT_CR_PW1, ltq_wdt_membase + LTQ_WDT_CR); /* write the second magic plus the configuration and new timeout */ - ltq_w32(LTQ_WDT_SR_EN | LTQ_WDT_SR_PWD | LTQ_WDT_SR_CLKDIV | - LTQ_WDT_PW2 | timeout, ltq_wdt_membase + LTQ_WDT_CR); + ltq_w32(LTQ_WDT_CR_GEN | LTQ_WDT_CR_PWL | LTQ_WDT_CR_CLKDIV | + LTQ_WDT_CR_PW2 | timeout, ltq_wdt_membase + LTQ_WDT_CR); }
static void ltq_wdt_disable(void) { /* write the first password magic */ - ltq_w32(LTQ_WDT_PW1, ltq_wdt_membase + LTQ_WDT_CR); + ltq_w32(LTQ_WDT_CR_PW1, ltq_wdt_membase + LTQ_WDT_CR); /* * write the second password magic with no config * this turns the watchdog off */ - ltq_w32(LTQ_WDT_PW2, ltq_wdt_membase + LTQ_WDT_CR); + ltq_w32(LTQ_WDT_CR_PW2, ltq_wdt_membase + LTQ_WDT_CR); }
static ssize_t