watchdog: lantiq: update register names to better match spec

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>
This commit is contained in:
Hauke Mehrtens 2018-09-13 23:32:09 +02:00 committed by Wim Van Sebroeck
parent 2e0432f8f8
commit 1f59f8aff9

View File

@ -13,6 +13,7 @@
#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>
@ -40,18 +41,19 @@
* 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_SR 0x8 /* watchdog status register */
#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_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;
@ -68,26 +70,26 @@ 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