On Mon, Dec 20, 2010 at 7:51 AM, Santosh Shilimkar <santosh.shilimkar@xxxxxx> wrote: >> -----Original Message----- >> From: linux-omap-owner@xxxxxxxxxxxxxxx [mailto:linux-omap- >> owner@xxxxxxxxxxxxxxx] On Behalf Of Nishanth Menon >> Sent: Sunday, December 19, 2010 4:24 AM >> To: linux-omap; linux-arm >> Cc: Jean Pihet; Kevin; Tony >> Subject: [PATCH v4 7/7] OMAP3630: PM: Erratum i583: disable coreoff if < >> ES1.2 >> >> From: Eduardo Valentin <eduardo.valentin@xxxxxxxxx> >> >> Limitation i583: Self_Refresh Exit issue after OFF mode >> >> Issue: >> When device is waking up from OFF mode, then SDRC state machine sends >> inappropriate sequence violating JEDEC standards. >> >> Impact: >> OMAP3630 < ES1.2 is impacted as follows depending on the platform: >> CS0: for 38.4MHz as internal sysclk, DDR content seen to be stable, > while >> for all other sysclk frequencies, varied levels of instability >> seen based on varied parameters. >> CS1: impacted >> >> This patch takes option #3 as recommended by the Silicon erratum: >> Avoid core power domain transitioning to OFF mode. Power consumption >> impact is expected in this case. >> To do this, we route core OFF requests to RET request on the impacted >> revisions of silicon. >> >> [nm@xxxxxx: rebased the code to 2.6.37-rc2- short circuit code changed a >> bit] >> Signed-off-by: Nishanth Menon <nm@xxxxxx> >> Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxxxxx> >> --- >> v4: idle state control changed a bit -we wont register or enable >> the states which cannot be enabled. >> v3: http://marc.info/?t=129140247800027&r=1&w=2 >> no functional change in erratum wa implementation, just registration >> of >> erratum is collated to a single cpu detection and version check >> v2: https://patchwork.kernel.org/patch/365262/ >> rebased to this patch series instead of depending on hs changes >> fix typo for macro definition >> v1: http://marc.info/?l=linux-omap&m=129013173425266&w=2 >> arch/arm/mach-omap2/cpuidle34xx.c | 10 ++++++++++ >> arch/arm/mach-omap2/pm.h | 1 + >> arch/arm/mach-omap2/pm34xx.c | 24 +++++++++++++++++++++--- >> 3 files changed, 32 insertions(+), 3 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/cpuidle34xx.c b/arch/arm/mach- >> omap2/cpuidle34xx.c >> index f80d3f6..1b32e98 100644 >> --- a/arch/arm/mach-omap2/cpuidle34xx.c >> +++ b/arch/arm/mach-omap2/cpuidle34xx.c >> @@ -453,6 +453,16 @@ void omap_init_power_states(void) >> omap3_power_states[OMAP3_STATE_C7].core_state = PWRDM_POWER_OFF; >> omap3_power_states[OMAP3_STATE_C7].flags = CPUIDLE_FLAG_TIME_VALID > | >> CPUIDLE_FLAG_CHECK_BM; >> + >> + /* >> + * Erratum i583: implementation for ES rev < Es1.2 on 3630. We >> cannot >> + * enable OFF mode in a stable form for previous revisions. >> + * we disable C7 state as a result. >> + */ >> + if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583)) { >> + omap3_power_states[OMAP3_STATE_C7].valid = 0; >> + cpuidle_params_table[OMAP3_STATE_C7].valid = 0; > WARN_ONCE in IDLE also would be good. Agree on the WARN_ONCE remarks. Other than that: Acked-by: Jean Pihet <j-pihet@xxxxxx> >> + } >> } >> >> struct cpuidle_driver omap3_idle_driver = { >> diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h >> index 92ef400..9032d09 100644 >> --- a/arch/arm/mach-omap2/pm.h >> +++ b/arch/arm/mach-omap2/pm.h >> @@ -87,6 +87,7 @@ extern unsigned int omap24xx_cpu_suspend_sz; >> extern unsigned int omap34xx_cpu_suspend_sz; >> >> #define PM_RTA_ERRATUM_i608 (1 << 0) >> +#define PM_SDRC_WAKEUP_ERRATUM_i583 (1 << 1) >> >> #if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3) >> extern u16 pm34xx_errata; >> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c >> index 21cd36e..7faea55 100644 >> --- a/arch/arm/mach-omap2/pm34xx.c >> +++ b/arch/arm/mach-omap2/pm34xx.c >> @@ -928,12 +928,28 @@ void omap3_pm_off_mode_enable(int enable) >> state = PWRDM_POWER_RET; >> >> #ifdef CONFIG_CPU_IDLE >> - omap3_cpuidle_update_states(state, state); >> + /* >> + * Erratum i583: implementation for ES rev < Es1.2 on 3630. We >> cannot >> + * enable OFF mode in a stable form for previous revisions, > restrict >> + * instead to RET >> + */ >> + if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583)) >> + omap3_cpuidle_update_states(state, PWRDM_POWER_RET); >> + else >> + omap3_cpuidle_update_states(state, state); >> #endif >> >> list_for_each_entry(pwrst, &pwrst_list, node) { >> - pwrst->next_state = state; >> - omap_set_pwrdm_state(pwrst->pwrdm, state); >> + if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) && >> + pwrst->pwrdm == core_pwrdm && >> + state == PWRDM_POWER_OFF) { >> + pwrst->next_state = PWRDM_POWER_RET; >> + pr_err("%s: Core OFF disabled due to errata > i583\n", > Shoud we do this in every iteration or just WARN_ONCE do ?? >> + __func__); >> + } else { >> + pwrst->next_state = state; >> + } >> + omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state); >> } >> } >> >> @@ -1011,6 +1027,8 @@ static void __init pm_errata_configure(void) >> pm34xx_errata |= PM_RTA_ERRATUM_i608; >> /* Enable the l2 cache toggling in sleep logic */ >> enable_omap3630_toggle_l2_on_restore(); >> + if (omap_rev() < OMAP3630_REV_ES1_2) >> + pm34xx_errata |= PM_SDRC_WAKEUP_ERRATUM_i583; >> } >> } >> >> -- >> 1.6.3.3 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-omap" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
