On Thursday 15 May 2014 02:32 PM, Tony Lindgren wrote:
- Alex Shi alex.shi@linaro.org [140515 06:27]:
On 05/15/2014 05:05 PM, Daniel Lezcano wrote:
After enable this patch, system maybe hang in idle. :(
Hi Alex,
do you mean even with this revert applied, the board hangs in idle ?
yes. My board is panda ES. without this revert, it works.
Care to specify what linux version you are testing against?
Does it hang in idle always immediately on booting?
Or does the serial console first hang with sysrq still working (ctrl-a h in minicom for help) with device eventually locking up hard?
I just posted an updated patch Alex on other thread. Attaching here again for your reference. Please try it out and see if the you still get a hang.
Regards, Santosh
From bb3b82cc5645b83bedf1343d03cc956f27f6fc83 Mon Sep 17 00:00:00 2001
From: Santosh Shilimkar santosh.shilimkar@ti.com Date: Mon, 12 May 2014 17:37:59 -0400 Subject: [PATCH] ARM: OMAP4: Fix the boot regression with CPU_IDLE enabled
On OMAP4 panda board, there have been several bug reports about boot hang and lock-ups with CPU_IDLE enabled. The root cause of the issue is missing interrupts while in idle state. Commit cb7094e8 {cpuidle / omap4 : use CPUIDLE_FLAG_TIMER_STOP flag} moved the broadcast notifiers to common code for right reasons but on OMAP4 which suffers from a nasty ROM code bug with GIC, commit ff999b8a {ARM: OMAP4460: Workaround for ROM bug ..}, we loose interrupts which leads to issues like lock-up, hangs etc.
Patch reverts commit cb7094 {cpuidle / omap4 : use CPUIDLE_FLAG_TIMER_STOP flag} and 54769d6 {cpuidle: OMAP4: remove timer broadcast initialization} to avoid the issue. With this change, OMAP4 panda boards, the mentioned issues are getting fixed. We no longer loose interrupts which was the cause of the regression.
Cc: Roger Quadros rogerq@ti.com Cc: Kevin Hilman khilman@linaro.org Cc: Tony Lindgren tony@atomide.com Cc: Daniel Lezcano daniel.lezcano@linaro.org Reported-tested-by: Roger Quadros rogerq@ti.com Reported-tested-by: Kevin Hilman khilman@linaro.org Tested-by: Tony Lindgren tony@atomide.com Signed-off-by: Santosh Shilimkar santosh.shilimkar@ti.com --- arch/arm/mach-omap2/cpuidle44xx.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c index 01fc710..2498ab0 100644 --- a/arch/arm/mach-omap2/cpuidle44xx.c +++ b/arch/arm/mach-omap2/cpuidle44xx.c @@ -14,6 +14,7 @@ #include <linux/cpuidle.h> #include <linux/cpu_pm.h> #include <linux/export.h> +#include <linux/clockchips.h>
#include <asm/cpuidle.h> #include <asm/proc-fns.h> @@ -83,6 +84,7 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, { struct idle_statedata *cx = state_ptr + index; u32 mpuss_can_lose_context = 0; + int cpu_id = smp_processor_id();
/* * CPU0 has to wait and stay ON until CPU1 is OFF state. @@ -110,6 +112,8 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, mpuss_can_lose_context = (cx->mpu_state == PWRDM_POWER_RET) && (cx->mpu_logic_state == PWRDM_POWER_OFF);
+ clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu_id); + /* * Call idle CPU PM enter notifier chain so that * VFP and per CPU interrupt context is saved. @@ -165,6 +169,8 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, if (dev->cpu == 0 && mpuss_can_lose_context) cpu_cluster_pm_exit();
+ clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu_id); + fail: cpuidle_coupled_parallel_barrier(dev, &abort_barrier); cpu_done[dev->cpu] = false; @@ -172,6 +178,16 @@ fail: return index; }
+/* + * For each cpu, setup the broadcast timer because local timers + * stops for the states above C1. + */ +static void omap_setup_broadcast_timer(void *arg) +{ + int cpu = smp_processor_id(); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ON, &cpu); +} + static struct cpuidle_driver omap4_idle_driver = { .name = "omap4_idle", .owner = THIS_MODULE, @@ -189,8 +205,7 @@ static struct cpuidle_driver omap4_idle_driver = { /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */ .exit_latency = 328 + 440, .target_residency = 960, - .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED | - CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED, .enter = omap_enter_idle_coupled, .name = "C2", .desc = "CPUx OFF, MPUSS CSWR", @@ -199,8 +214,7 @@ static struct cpuidle_driver omap4_idle_driver = { /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */ .exit_latency = 460 + 518, .target_residency = 1100, - .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED | - CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED, .enter = omap_enter_idle_coupled, .name = "C3", .desc = "CPUx OFF, MPUSS OSWR", @@ -231,5 +245,8 @@ int __init omap4_idle_init(void) if (!cpu_clkdm[0] || !cpu_clkdm[1]) return -ENODEV;
+ /* Configure the broadcast timer on each cpu */ + on_each_cpu(omap_setup_broadcast_timer, NULL, 1); + return cpuidle_register(&omap4_idle_driver, cpu_online_mask); }