diff options
author | Marian Balakowicz <m8@semihalf.com> | 2007-10-19 04:44:33 +1000 |
---|---|---|
committer | Grant Likely <grant.likely@secretlab.ca> | 2007-10-21 12:43:04 -0600 |
commit | 86b92cdda9e997dd305851cb16292c67076d58cb (patch) | |
tree | 6acfde248f5638e666442ef305347d190a50e115 /arch/powerpc | |
parent | d24bc314c964e900ddf30efa1ef44565cf0cf44c (diff) | |
download | talos-obmc-linux-86b92cdda9e997dd305851cb16292c67076d58cb.tar.gz talos-obmc-linux-86b92cdda9e997dd305851cb16292c67076d58cb.zip |
[POWERPC] Add restart support for mpc52xx based platforms
Add common helper routines: mpc52xx_map_wdt() and mpc52xx_restart().
Signed-off-by: Marian Balakowicz <m8@semihalf.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/platforms/52xx/mpc52xx_common.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_common.c b/arch/powerpc/platforms/52xx/mpc52xx_common.c index 74b4b4183842..9850685c5429 100644 --- a/arch/powerpc/platforms/52xx/mpc52xx_common.c +++ b/arch/powerpc/platforms/52xx/mpc52xx_common.c @@ -18,6 +18,13 @@ #include <asm/prom.h> #include <asm/mpc52xx.h> +/* + * This variable is mapped in mpc52xx_map_wdt() and used in mpc52xx_restart(). + * Permanent mapping is required because mpc52xx_restart() can be called + * from interrupt context while node mapping (which calls ioremap()) + * cannot be used at such point. + */ +static volatile struct mpc52xx_gpt *mpc52xx_wdt = NULL; static void __iomem * mpc52xx_map_node(struct device_node *ofn) @@ -126,3 +133,46 @@ mpc52xx_declare_of_platform_devices(void) "Error while probing of_platform bus\n"); } +void __init +mpc52xx_map_wdt(void) +{ + const void *has_wdt; + struct device_node *np; + + /* mpc52xx_wdt is mapped here and used in mpc52xx_restart, + * possibly from a interrupt context. wdt is only implement + * on a gpt0, so check has-wdt property before mapping. + */ + for_each_compatible_node(np, NULL, "fsl,mpc5200-gpt") { + has_wdt = of_get_property(np, "fsl,has-wdt", NULL); + if (has_wdt) { + mpc52xx_wdt = mpc52xx_map_node(np); + return; + } + } + for_each_compatible_node(np, NULL, "mpc5200-gpt") { + has_wdt = of_get_property(np, "has-wdt", NULL); + if (has_wdt) { + mpc52xx_wdt = mpc52xx_map_node(np); + return; + } + } +} + +void +mpc52xx_restart(char *cmd) +{ + local_irq_disable(); + + /* Turn on the watchdog and wait for it to expire. + * It effectively does a reset. */ + if (mpc52xx_wdt) { + out_be32(&mpc52xx_wdt->mode, 0x00000000); + out_be32(&mpc52xx_wdt->count, 0x000000ff); + out_be32(&mpc52xx_wdt->mode, 0x00009004); + } else + printk("mpc52xx_restart: Can't access wdt. " + "Restart impossible, system halted.\n"); + + while (1); +} |