"ext Rajendra Nayak" <rnayak@xxxxxx> writes: > > >> -----Original Message----- >> From: linux-omap-owner@xxxxxxxxxxxxxxx >> [mailto:linux-omap-owner@xxxxxxxxxxxxxxx] On Behalf Of Jouni Hogander >> Sent: Wednesday, June 25, 2008 2:44 PM >> To: linux-omap@xxxxxxxxxxxxxxx >> Subject: [PATCH 6/7] 34XX: PM: Workaround for taking care of >> gpio clocks >> >> In omap3 gpios 2-6 are in per domain. Clocks for these should be >> disabled. This patch is needed until gpio driver disables gpio clocks. >> >> Signed-off-by: Jouni Hogander <jouni.hogander@xxxxxxxxx> >> --- >> arch/arm/mach-omap2/pm34xx.c | 15 +++++++- >> arch/arm/mach-omap2/sleep34xx.S | 74 >> +++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 87 insertions(+), 2 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/pm34xx.c >> b/arch/arm/mach-omap2/pm34xx.c >> index edde254..9c7b7be 100644 >> --- a/arch/arm/mach-omap2/pm34xx.c >> +++ b/arch/arm/mach-omap2/pm34xx.c >> @@ -47,12 +47,19 @@ struct power_state { >> >> static LIST_HEAD(pwrst_list); >> >> -void (*_omap_sram_idle)(u32 *addr, int save_state); >> +void (*_omap_sram_idle)(u32 *addr, int save_state, int >> disable_clocks); >> >> static void (*saved_idle)(void); >> >> static struct powerdomain *mpu_pwrdm; >> >> +/* XXX This is for gpio fclk hack. Will be removed as gpio driver >> + * handles fcks correctly */ >> +static void gpio_fclk_mask(u32 *fclk) >> +{ >> + *fclk &= ~(0x1f << 13); >> +} >> + >> /* PRCM Interrupt Handler for wakeups */ >> static irqreturn_t prcm_interrupt_handler (int irq, void *dev_id) >> { >> @@ -169,7 +176,7 @@ static void omap_sram_idle(void) >> >> omap2_gpio_prepare_for_retention(); >> >> - _omap_sram_idle(NULL, save_state); >> + _omap_sram_idle(NULL, save_state, clocks_off_while_idle); >> >> omap2_gpio_resume_after_retention(); >> } >> @@ -197,6 +204,10 @@ static int omap3_fclks_active(void) >> CM_FCLKEN); >> fck_per = cm_read_mod_reg(OMAP3430_PER_MOD, >> CM_FCLKEN); >> + >> + if (clocks_off_while_idle) >> + gpio_fclk_mask(&fck_per); >> + >> if (fck_core1 | fck_core3 | fck_sgx | fck_dss | >> fck_cam | fck_per | fck_usbhost) >> return 1; >> diff --git a/arch/arm/mach-omap2/sleep34xx.S >> b/arch/arm/mach-omap2/sleep34xx.S >> index ebc7eb3..1f7009a 100644 >> --- a/arch/arm/mach-omap2/sleep34xx.S >> +++ b/arch/arm/mach-omap2/sleep34xx.S >> @@ -32,6 +32,8 @@ >> >> #include "prm.h" >> #include "sdrc.h" >> +#include "cm.h" >> +#include "cm-regbits-34xx.h" >> >> #define PM_PREPWSTST_CORE_V OMAP34XX_PRM_REGADDR(CORE_MOD, \ >> OMAP3430_PM_PREPWSTST) >> @@ -45,6 +47,15 @@ >> SCRATCHPAD_MEM_OFFS) >> #define SDRC_POWER_V OMAP34XX_SDRC_REGADDR(SDRC_POWER) >> >> +/* XXX gpio fclk workaround */ >> +#define CM_FCLKEN_PER_V >> OMAP34XX_CM_REGADDR(OMAP3430_PER_MOD, \ >> + CM_FCLKEN) >> +#define CM_FCLKEN_PER_P io_v2p(CM_FCLKEN_PER_V) >> + >> +#define GPIO_FCLK_MASK OMAP3430_EN_GPIO6 | >> OMAP3430_EN_GPIO5 | \ >> + OMAP3430_EN_GPIO4 | >> OMAP3430_EN_GPIO3 | \ >> + OMAP3430_EN_GPIO2 >> + >> .text >> /* Function call to get the restore pointer for resume from OFF */ >> ENTRY(get_restore_pointer) >> @@ -68,14 +79,41 @@ loop: >> /*b loop*/ @Enable to debug by stepping through code >> /* r0 contains restore pointer in sdram */ >> /* r1 contains information about saving context */ >> + /* r2 contains information whether clocks should be disabled */ >> ldr r4, sdrc_power @ read the SDRC_POWER register >> ldr r5, [r4] @ read the contents of >> SDRC_POWER >> orr r5, r5, #0x40 @ enable self refresh >> on idle req >> str r5, [r4] @ write back to >> SDRC_POWER register >> >> + /* XXX gpio fclk workaround */ >> + /* Check if per fclken needs to be saved */ >> + cmp r2, #0x0 >> + beq skip_per_fclken_save >> + >> + /* XXX gpio fclk workaround */ >> + /* Save current value of per fclken reg */ >> + ldr r4, cm_fclken_per_v >> + ldr r5, [r4] >> + str r5, cm_fclken_per_val >> +skip_per_fclken_save: >> + > > Any reason why this is now done in SRAM? Because of the fact that gpios in per domain are not able to generate wakeup/interrupt if per domain is not active. We want to put per domain into sleep state as late as possible. IOPAD wakeup starts to work only after mpu enters its sleep state. > >> cmp r1, #0x0 >> /* If context save is required, do that and execute wfi */ >> bne save_context_wfi > > In case of OFF mode, clocks would never be disabled. Isn't it done below. I might be wrong because I haven't been able to test this with off mode. > >> + >> + /* XXX gpio fclk workaround */ >> + /* Check if gpio clocks needs to be disabled */ >> + ldr r5, cm_fclken_per_val >> + cmp r5, #0x0 >> + beq skip_gpio_clk_disable >> + >> + /* XXX gpio fclk workaround */ >> + /* Disable gpio clocks */ >> + ldr r4, cm_fclken_per_v >> + bic r5, r5, #GPIO_FCLK_MASK >> + str r5, [r4] >> +skip_gpio_clk_disable: > > Even with clocks_off_while_idle set to 1, should'nt gpio clocks be cut and restored only > when a PER RET/OFF is attemted and not every time omap_sram_idle is > called? Where this would then happen if not in sram? I mean gpio clock control is not in current gpio code and adding that into it needs huge effort. I'm not sure if it can be even handled there, because of this wakeup problem. Basically we have this need to keep per gpios active as long as possible, because after disabling their clocks they wont generate interrupts/wakeups until mpu is in ret or off mode. > >> + >> /* Data memory barrier and Data sync barrier */ >> mov r1, #0 >> mcr p15, 0, r1, c7, c10, 4 >> @@ -93,6 +131,14 @@ loop: >> nop >> nop >> nop >> + >> + /* XXX gpio fclk workaround */ >> + ldr r5, cm_fclken_per_val >> + cmp r5, #0x0 >> + beq skip_per_fclken_restore >> + str r5, [r4] >> +skip_per_fclken_restore: >> + >> bl i_dll_wait >> >> ldmfd sp!, {r0-r12, pc} @ restore regs >> and return >> @@ -483,6 +529,20 @@ finished: >> mcr p15, 2, r10, c0, c0, 0 >> isb >> skip_l2_inval: >> + >> + /* XXX gpio fclk workaround */ >> + /* Check if gpio clocks needs to be disabled */ >> + ldr r5, cm_fclken_per_val >> + cmp r5, #0x0 >> + beq skip_gpio_clk_disable_2 >> + >> + /* XXX gpio fclk workaround */ >> + /* Disable gpio clocks */ >> + ldr r4, cm_fclken_per_p >> + bic r5, r5, #GPIO_FCLK_MASK >> + str r5, [r4] >> +skip_gpio_clk_disable_2: >> + >> /* Data memory barrier and Data sync barrier */ >> mov r1, #0 >> mcr p15, 0, r1, c7, c10, 4 >> @@ -499,6 +559,14 @@ skip_l2_inval: >> nop >> nop >> nop >> + >> + /* XXX gpio fclk workaround */ >> + ldr r5, cm_fclken_per_val >> + cmp r5, #0x0 >> + beq skip_per_fclken_restore_2 >> + str r5, [r4] >> +skip_per_fclken_restore_2: >> + >> bl i_dll_wait >> /* restore regs and return */ >> ldmfd sp!, {r0-r12, pc} >> @@ -540,5 +608,11 @@ table_entry: >> .word 0x00000C02 >> cache_pred_disable_mask: >> .word 0xFFFFE7FB >> +cm_fclken_per_v: >> + .word CM_FCLKEN_PER_V >> +cm_fclken_per_p: >> + .word CM_FCLKEN_PER_P >> +cm_fclken_per_val: >> + .word 0 >> ENTRY(omap34xx_cpu_suspend_sz) >> .word . - omap34xx_cpu_suspend >> -- >> 1.5.5 >> >> -- >> 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 >> > > > -- Jouni Högander -- 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
