Re: [PATCH] OMAP3 PM: Disable SR only during Device Retention/OFF
Vishwanath BS writes: > Currently in omap_sram_idle function, SR is disabled whenever next state > is retention/OFF w/o checking whether system can really enter retention/off. > This patch adds another condition to disable SR. Basically FCLK register for > Core and PER are checked before disabling SR. THis will give some more power > savings in MP3 usecase (where Core enters retention where as PER does not). > > Tested OMAP3430 ZOOM2 > > Signed-off-by: Vishwanath BS I'm not going to take this one in it's current form as we had discussions about this kind of thing earler when Tero had a series of adding various fclk checks into the idle path. I'm holding off on this patch until Tero's series is reviewed/merged. He has added some functionality to check idleness of clockdomains and powerdomains that could be used here. Kevin > --- > diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c > index 3868cdf..13c5dfb > --- a/arch/arm/mach-omap2/pm34xx.c > +++ b/arch/arm/mach-omap2/pm34xx.c > @@ -479,6 +479,7 @@ void omap_sram_idle(void) > int mpu_logic_state, mpu_mem_state, core_logic_state, core_mem_state; > u32 sdrc_pwr = 0; > int per_state_modified = 0; > + u32 fclk_status; > > if (!_omap_sram_idle) > return; > @@ -545,15 +546,6 @@ void omap_sram_idle(void) > if (pwrdm_read_pwrst(cam_pwrdm) == PWRDM_POWER_ON) > omap2_clkdm_deny_idle(mpu_pwrdm->pwrdm_clkdms[0]); > > - /* > - * Disable smartreflex before entering WFI. > - * Only needed if we are going to enter retention or off. > - */ > - if (mpu_next_state <= PWRDM_POWER_RET) > - disable_smartreflex(SR1); > - if (core_next_state <= PWRDM_POWER_RET) > - disable_smartreflex(SR2); > - > /* CORE */ > if (core_next_state < PWRDM_POWER_ON) { > omap_uart_prepare_idle(0, core_next_state & core_logic_state); > @@ -600,6 +592,21 @@ void omap_sram_idle(void) > omap3_intc_prepare_idle(); > > /* > + * Disable smartreflex before entering WFI. > + * Only needed if we are going to enter retention or off. > + */ > + fclk_status = cm_read_mod_reg(OMAP3430_PER_MOD, CM_FCLKEN) | > + cm_read_mod_reg(CORE_MOD, CM_FCLKEN1) | > + cm_read_mod_reg(CORE_MOD, OMAP3430ES2_CM_FCLKEN3); > + > + if (!fclk_status) { > + if (mpu_next_state <= PWRDM_POWER_RET) > + disable_smartreflex(SR1); > + if (core_next_state <= PWRDM_POWER_RET) > + disable_smartreflex(SR2); > + } > + > + /* > * On EMU/HS devices ROM code restores a SRDC value > * from scratchpad which has automatic self refresh on timeout > * of AUTO_CNT = 1 enabled. This takes care of errata 1.142. > @@ -685,11 +692,12 @@ void omap_sram_idle(void) >* Enable smartreflex after WFI. Only needed if we entered >* retention or off >*/ > - if (mpu_next_state <= PWRDM_POWER_RET) > - enable_smartreflex(SR1); > - if (core_next_state <= PWRDM_POWER_RET) > - enable_smartreflex(SR2); > - > + if (!fclk_status) { > + if (mpu_next_state <= PWRDM_POWER_RET) > + enable_smartreflex(SR1); > + if (core_next_state <= PWRDM_POWER_RET) > + enable_smartreflex(SR2); > + } > /* PER */ > if (per_next_state < PWRDM_POWER_ON) { > if (per_next_state == PWRDM_POWER_OFF) { > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majord...@vger.kernel.org > 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: [PATCH] OMAP3 PM: Disable SR only during Device Retention/OFF
Kevin, Can you pls take this patch if there are no comments? Regards Vishwa > -Original Message- > From: linux-omap-ow...@vger.kernel.org [mailto:linux-omap- > ow...@vger.kernel.org] On Behalf Of Sripathy, Vishwanath > Sent: Thursday, January 07, 2010 11:22 AM > To: linux-omap@vger.kernel.org > Subject: [PATCH] OMAP3 PM: Disable SR only during Device Retention/OFF > > Currently in omap_sram_idle function, SR is disabled whenever next state > is retention/OFF w/o checking whether system can really enter retention/off. > This patch adds another condition to disable SR. Basically FCLK register for > Core and PER are checked before disabling SR. THis will give some more power > savings in MP3 usecase (where Core enters retention where as PER does not). > > Tested OMAP3430 ZOOM2 > > Signed-off-by: Vishwanath BS > --- > diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c > index 3868cdf..13c5dfb > --- a/arch/arm/mach-omap2/pm34xx.c > +++ b/arch/arm/mach-omap2/pm34xx.c > @@ -479,6 +479,7 @@ void omap_sram_idle(void) > int mpu_logic_state, mpu_mem_state, core_logic_state, core_mem_state; > u32 sdrc_pwr = 0; > int per_state_modified = 0; > + u32 fclk_status; > > if (!_omap_sram_idle) > return; > @@ -545,15 +546,6 @@ void omap_sram_idle(void) > if (pwrdm_read_pwrst(cam_pwrdm) == PWRDM_POWER_ON) > omap2_clkdm_deny_idle(mpu_pwrdm->pwrdm_clkdms[0]); > > - /* > - * Disable smartreflex before entering WFI. > - * Only needed if we are going to enter retention or off. > - */ > - if (mpu_next_state <= PWRDM_POWER_RET) > - disable_smartreflex(SR1); > - if (core_next_state <= PWRDM_POWER_RET) > - disable_smartreflex(SR2); > - > /* CORE */ > if (core_next_state < PWRDM_POWER_ON) { > omap_uart_prepare_idle(0, core_next_state & core_logic_state); > @@ -600,6 +592,21 @@ void omap_sram_idle(void) > omap3_intc_prepare_idle(); > > /* > + * Disable smartreflex before entering WFI. > + * Only needed if we are going to enter retention or off. > + */ > + fclk_status = cm_read_mod_reg(OMAP3430_PER_MOD, CM_FCLKEN) | > + cm_read_mod_reg(CORE_MOD, CM_FCLKEN1) | > + cm_read_mod_reg(CORE_MOD, OMAP3430ES2_CM_FCLKEN3); > + > + if (!fclk_status) { > + if (mpu_next_state <= PWRDM_POWER_RET) > + disable_smartreflex(SR1); > + if (core_next_state <= PWRDM_POWER_RET) > + disable_smartreflex(SR2); > + } > + > + /* > * On EMU/HS devices ROM code restores a SRDC value > * from scratchpad which has automatic self refresh on timeout > * of AUTO_CNT = 1 enabled. This takes care of errata 1.142. > @@ -685,11 +692,12 @@ void omap_sram_idle(void) >* Enable smartreflex after WFI. Only needed if we entered >* retention or off >*/ > - if (mpu_next_state <= PWRDM_POWER_RET) > - enable_smartreflex(SR1); > - if (core_next_state <= PWRDM_POWER_RET) > - enable_smartreflex(SR2); > - > + if (!fclk_status) { > + if (mpu_next_state <= PWRDM_POWER_RET) > + enable_smartreflex(SR1); > + if (core_next_state <= PWRDM_POWER_RET) > + enable_smartreflex(SR2); > + } > /* PER */ > if (per_next_state < PWRDM_POWER_ON) { > if (per_next_state == PWRDM_POWER_OFF) { > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majord...@vger.kernel.org > 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html