diff options
author | Johan Hovold <jhovold@gmail.com> | 2013-10-16 11:56:15 +0200 |
---|---|---|
committer | Nicolas Ferre <nicolas.ferre@atmel.com> | 2013-11-15 12:13:33 +0100 |
commit | 94c4c79f2f1acca6e69a50bff5a7d9027509c16b (patch) | |
tree | 85b5fdb02f99edb8b8f4368ea932c4d149fc9e1f /arch/arm/mach-at91 | |
parent | 6de714c21a8ea315fffba6a93bbe537f4c1bf4f0 (diff) | |
download | op-kernel-dev-94c4c79f2f1acca6e69a50bff5a7d9027509c16b.zip op-kernel-dev-94c4c79f2f1acca6e69a50bff5a7d9027509c16b.tar.gz |
ARM: at91: fix hanged boot due to early rtt-interrupt
Make sure the RTT-interrupts are masked at boot by adding a new helper
function to be used at SOC-init.
This fixes hanged boot on all AT91 SOCs with an RTT, for example, if an
RTT-alarm goes off after a non-clean shutdown (e.g. when using RTC
wakeup).
The RTC and RTT-peripherals are powered by backup power (VDDBU) (on all
AT91 SOCs but RM9200) and are not reset on wake-up, user, watchdog or
software reset. This means that their interrupts may be enabled during
early boot if, for example, they where not disabled during a previous
shutdown (e.g. due to a buggy driver or a non-clean shutdown such as a
user reset). Furthermore, an RTC or RTT-alarm may also be active.
The RTC and RTT-interrupts use the shared system-interrupt line, which
is also used by the PIT, and if an interrupt occurs before a handler
(e.g. RTC-driver) has been installed this leads to the system interrupt
being disabled and prevents the system from booting.
Note that when boot hangs due to an early RTC or RTT-interrupt, the only
way to get the system to start again is to remove the backup power (e.g.
battery) or to disable the interrupt manually from the bootloader. In
particular, a user reset is not sufficient.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: stable@vger.kernel.org # 3.11.x
Diffstat (limited to 'arch/arm/mach-at91')
-rw-r--r-- | arch/arm/mach-at91/at91sam9260.c | 2 | ||||
-rw-r--r-- | arch/arm/mach-at91/at91sam9261.c | 2 | ||||
-rw-r--r-- | arch/arm/mach-at91/at91sam9263.c | 3 | ||||
-rw-r--r-- | arch/arm/mach-at91/at91sam9g45.c | 1 | ||||
-rw-r--r-- | arch/arm/mach-at91/at91sam9rl.c | 1 | ||||
-rw-r--r-- | arch/arm/mach-at91/generic.h | 1 | ||||
-rw-r--r-- | arch/arm/mach-at91/sysirq_mask.c | 24 |
7 files changed, 34 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/at91sam9260.c b/arch/arm/mach-at91/at91sam9260.c index 5de6074..ae10d14 100644 --- a/arch/arm/mach-at91/at91sam9260.c +++ b/arch/arm/mach-at91/at91sam9260.c @@ -349,6 +349,8 @@ static void __init at91sam9260_initialize(void) arm_pm_idle = at91sam9_idle; arm_pm_restart = at91sam9_alt_restart; + at91_sysirq_mask_rtt(AT91SAM9260_BASE_RTT); + /* Register GPIO subsystem */ at91_gpio_init(at91sam9260_gpio, 3); } diff --git a/arch/arm/mach-at91/at91sam9261.c b/arch/arm/mach-at91/at91sam9261.c index 0e07932..e761e74 100644 --- a/arch/arm/mach-at91/at91sam9261.c +++ b/arch/arm/mach-at91/at91sam9261.c @@ -291,6 +291,8 @@ static void __init at91sam9261_initialize(void) arm_pm_idle = at91sam9_idle; arm_pm_restart = at91sam9_alt_restart; + at91_sysirq_mask_rtt(AT91SAM9261_BASE_RTT); + /* Register GPIO subsystem */ at91_gpio_init(at91sam9261_gpio, 3); } diff --git a/arch/arm/mach-at91/at91sam9263.c b/arch/arm/mach-at91/at91sam9263.c index 6ce7d18..e6fed62 100644 --- a/arch/arm/mach-at91/at91sam9263.c +++ b/arch/arm/mach-at91/at91sam9263.c @@ -328,6 +328,9 @@ static void __init at91sam9263_initialize(void) arm_pm_idle = at91sam9_idle; arm_pm_restart = at91sam9_alt_restart; + at91_sysirq_mask_rtt(AT91SAM9263_BASE_RTT0); + at91_sysirq_mask_rtt(AT91SAM9263_BASE_RTT1); + /* Register GPIO subsystem */ at91_gpio_init(at91sam9263_gpio, 5); } diff --git a/arch/arm/mach-at91/at91sam9g45.c b/arch/arm/mach-at91/at91sam9g45.c index ff662af..9f7a97c 100644 --- a/arch/arm/mach-at91/at91sam9g45.c +++ b/arch/arm/mach-at91/at91sam9g45.c @@ -378,6 +378,7 @@ static void __init at91sam9g45_initialize(void) arm_pm_restart = at91sam9g45_restart; at91_sysirq_mask_rtc(AT91SAM9G45_BASE_RTC); + at91_sysirq_mask_rtt(AT91SAM9G45_BASE_RTT); /* Register GPIO subsystem */ at91_gpio_init(at91sam9g45_gpio, 5); diff --git a/arch/arm/mach-at91/at91sam9rl.c b/arch/arm/mach-at91/at91sam9rl.c index b5a8c9d..301e172 100644 --- a/arch/arm/mach-at91/at91sam9rl.c +++ b/arch/arm/mach-at91/at91sam9rl.c @@ -295,6 +295,7 @@ static void __init at91sam9rl_initialize(void) arm_pm_restart = at91sam9_alt_restart; at91_sysirq_mask_rtc(AT91SAM9RL_BASE_RTC); + at91_sysirq_mask_rtt(AT91SAM9RL_BASE_RTT); /* Register GPIO subsystem */ at91_gpio_init(at91sam9rl_gpio, 4); diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h index 80269bd..26dee3c 100644 --- a/arch/arm/mach-at91/generic.h +++ b/arch/arm/mach-at91/generic.h @@ -35,6 +35,7 @@ extern int __init at91_aic_of_init(struct device_node *node, extern int __init at91_aic5_of_init(struct device_node *node, struct device_node *parent); extern void __init at91_sysirq_mask_rtc(u32 rtc_base); +extern void __init at91_sysirq_mask_rtt(u32 rtt_base); /* Timer */ diff --git a/arch/arm/mach-at91/sysirq_mask.c b/arch/arm/mach-at91/sysirq_mask.c index ee3e22c..2ba694f 100644 --- a/arch/arm/mach-at91/sysirq_mask.c +++ b/arch/arm/mach-at91/sysirq_mask.c @@ -21,6 +21,7 @@ */ #include <linux/io.h> +#include <mach/at91_rtt.h> #include "generic.h" @@ -45,3 +46,26 @@ void __init at91_sysirq_mask_rtc(u32 rtc_base) iounmap(base); } + +void __init at91_sysirq_mask_rtt(u32 rtt_base) +{ + void __iomem *base; + void __iomem *reg; + u32 mode; + + base = ioremap(rtt_base, 16); + if (!base) + return; + + reg = base + AT91_RTT_MR; + + mode = readl_relaxed(reg); + if (mode & (AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN)) { + pr_info("AT91: Disabling rtt irq\n"); + mode &= ~(AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN); + writel_relaxed(mode, reg); + (void)readl_relaxed(reg); /* flush */ + } + + iounmap(base); +} |