Hello Jon On Thu, 7 Jun 2012, Jon Hunter wrote: > By removing the CLKDM_CAN_ENABLE_AUTO flag, the EMU clock domain will always > remain on and hence, this will break low-power modes. The EMU clock domain only > support the SW_WKUP and HW_AUTO transition modes (for more details refer to the > OMAP4430 TRM) and power down the EMU power domain we need to place the EMU > clock domain back into the HW_AUTO mode. This can be accomplished by setting > the CLKDM_CAN_FORCE_SLEEP flag, which for an OMAP4 device will enable the > HW_AUTO mode. Hmm, it would be nice if we could keep the CLKDM_CAN_* flags matching the hardware capabilities. Looking at the 4430 TRM Rev X Table 3-744 "CM_EMU_CLKSTCTRL", the CLKTRCTRL field isn't documented as supporting the SW_SLEEP mode (which CLKDM_CAN_FORCE_SLEEP will set). Maybe the CLKDM_CAN_* flags should be moved to a separate u8... Anyway, what do you think about the following approach? It uses a special flag to indicate that the EMU clockdomain is behaving in an unexpected way. If you think it's reasonable, perhaps you could try your PMU tests with it? It applies on top of linux-omap master (cb07e3394573a419147a1783f3bd7ef13045353c) plus the clockdomain patch posted earlier at: http://marc.info/?l=linux-omap&m=134209072829531&w=2 But these patches may need to be applied on Kevin's 'pm' branch for meaningful PM testing: http://marc.info/?l=linux-omap&m=134196493819792&w=2 - Paul From: Paul Walmsley <paul@xxxxxxxxx> Date: Thu, 12 Jul 2012 14:58:43 -0600 Subject: [PATCH] ARM: OMAP2+: clockdomain/hwmod: add workaround for EMU clockdomain idle problems The idle status of the IP blocks and clocks inside the EMU clockdomain isn't taken into account by the PRCM hardware when deciding whether the clockdomain is idle. Add a workaround flag, CLKDM_MISSING_IDLE_REPORTING, to deal with this problem, and add the code necessary to support it. XXX Add more description of what this flag actually does XXX Jon, Ming, Will --- arch/arm/mach-omap2/clockdomain.c | 17 ++++++ arch/arm/mach-omap2/clockdomain.h | 20 ++++++- arch/arm/mach-omap2/clockdomain2xxx_3xxx.c | 86 +++++++++++++++++---------- arch/arm/mach-omap2/clockdomain44xx.c | 11 ++++ arch/arm/mach-omap2/clockdomains3xxx_data.c | 7 +-- arch/arm/mach-omap2/clockdomains44xx_data.c | 3 +- arch/arm/mach-omap2/omap_hwmod.c | 3 +- 7 files changed, 105 insertions(+), 42 deletions(-) diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c index b851ba4..17b1d32 100644 --- a/arch/arm/mach-omap2/clockdomain.c +++ b/arch/arm/mach-omap2/clockdomain.c @@ -914,6 +914,23 @@ bool clkdm_in_hwsup(struct clockdomain *clkdm) return ret; } +/** + * clkdm_missing_idle_reporting - can @clkdm enter autoidle even if in use? + * @clkdm: struct clockdomain * + * + * Returns true if clockdomain @clkdm has the + * CLKDM_MISSING_IDLE_REPORTING flag set, or false if not or @clkdm is + * null. More information is available in the documentation for the + * CLKDM_MISSING_IDLE_REPORTING macro. + */ +bool clkdm_missing_idle_reporting(struct clockdomain *clkdm) +{ + if (!clkdm) + return false; + + return (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING) ? true : false; +} + /* Clockdomain-to-clock/hwmod framework interface code */ static int _clkdm_clk_hwmod_enable(struct clockdomain *clkdm) diff --git a/arch/arm/mach-omap2/clockdomain.h b/arch/arm/mach-omap2/clockdomain.h index 7b3c1d2..fb5d37f 100644 --- a/arch/arm/mach-omap2/clockdomain.h +++ b/arch/arm/mach-omap2/clockdomain.h @@ -1,9 +1,7 @@ /* - * arch/arm/plat-omap/include/mach/clockdomain.h - * * OMAP2/3 clockdomain framework functions * - * Copyright (C) 2008 Texas Instruments, Inc. + * Copyright (C) 2008, 2012 Texas Instruments, Inc. * Copyright (C) 2008-2011 Nokia Corporation * * Paul Walmsley @@ -34,6 +32,20 @@ * CLKDM_ACTIVE_WITH_MPU: The PRCM guarantees that this clockdomain is * active whenever the MPU is active. True for interconnects and * the WKUP clockdomains. + * CLKDM_MISSING_IDLE_REPORTING: The idle status of the IP blocks and + * clocks inside this clockdomain are not taken into account by + * the PRCM when determining whether the clockdomain is idle. + * Without this flag, if the clockdomain is set to + * hardware-supervised idle mode, the PRCM may transition the + * enclosing powerdomain to a low power state, even when devices + * inside the clockdomain and powerdomain are in use. (An example + * of such a clockdomain is the EMU clockdomain on OMAP3/4.) If + * this flag is set, and the clockdomain does not support the + * force-sleep mode, then the HW_AUTO mode will be used to put the + * clockdomain to sleep. Similarly, if the clockdomain supports + * the force-wakeup mode, then it will be used whenever a clock or + * IP block inside the clockdomain is active, rather than the + * HW_AUTO mode. */ #define CLKDM_CAN_FORCE_SLEEP (1 << 0) #define CLKDM_CAN_FORCE_WAKEUP (1 << 1) @@ -41,6 +53,7 @@ #define CLKDM_CAN_DISABLE_AUTO (1 << 3) #define CLKDM_NO_AUTODEPS (1 << 4) #define CLKDM_ACTIVE_WITH_MPU (1 << 5) +#define CLKDM_MISSING_IDLE_REPORTING (1 << 6) #define CLKDM_CAN_HWSUP (CLKDM_CAN_ENABLE_AUTO | CLKDM_CAN_DISABLE_AUTO) #define CLKDM_CAN_SWSUP (CLKDM_CAN_FORCE_SLEEP | CLKDM_CAN_FORCE_WAKEUP) @@ -188,6 +201,7 @@ int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm); void clkdm_allow_idle(struct clockdomain *clkdm); void clkdm_deny_idle(struct clockdomain *clkdm); bool clkdm_in_hwsup(struct clockdomain *clkdm); +bool clkdm_missing_idle_reporting(struct clockdomain *clkdm); int clkdm_wakeup(struct clockdomain *clkdm); int clkdm_sleep(struct clockdomain *clkdm); diff --git a/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c b/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c index a0d68db..09385a9 100644 --- a/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c +++ b/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c @@ -162,6 +162,37 @@ static void _disable_hwsup(struct clockdomain *clkdm) clkdm->clktrctrl_mask); } +static int omap3_clkdm_sleep(struct clockdomain *clkdm) +{ + omap3xxx_cm_clkdm_force_sleep(clkdm->pwrdm.ptr->prcm_offs, + clkdm->clktrctrl_mask); + return 0; +} + +static int omap3_clkdm_wakeup(struct clockdomain *clkdm) +{ + omap3xxx_cm_clkdm_force_wakeup(clkdm->pwrdm.ptr->prcm_offs, + clkdm->clktrctrl_mask); + return 0; +} + +static void omap3_clkdm_allow_idle(struct clockdomain *clkdm) +{ + if (atomic_read(&clkdm->usecount) > 0) + _clkdm_add_autodeps(clkdm); + + omap3xxx_cm_clkdm_enable_hwsup(clkdm->pwrdm.ptr->prcm_offs, + clkdm->clktrctrl_mask); +} + +static void omap3_clkdm_deny_idle(struct clockdomain *clkdm) +{ + omap3xxx_cm_clkdm_disable_hwsup(clkdm->pwrdm.ptr->prcm_offs, + clkdm->clktrctrl_mask); + + if (atomic_read(&clkdm->usecount) > 0) + _clkdm_del_autodeps(clkdm); +} static int omap2_clkdm_clk_enable(struct clockdomain *clkdm) { @@ -170,6 +201,18 @@ static int omap2_clkdm_clk_enable(struct clockdomain *clkdm) if (!clkdm->clktrctrl_mask) return 0; + /* + * The CLKDM_MISSING_IDLE_REPORTING flag documentation has + * more details on the unpleasant problem this is working + * around + */ + if (clkdm->flags & (CLKDM_MISSING_IDLE_REPORTING | + CLKDM_CAN_FORCE_WAKEUP)) { + (cpu_is_omap24xx()) ? omap2_clkdm_wakeup(clkdm) : + omap3_clkdm_wakeup(clkdm); + return 0; + } + hwsup = omap2_cm_is_clkdm_in_hwsup(clkdm->pwrdm.ptr->prcm_offs, clkdm->clktrctrl_mask); @@ -193,6 +236,17 @@ static int omap2_clkdm_clk_disable(struct clockdomain *clkdm) if (!clkdm->clktrctrl_mask) return 0; + /* + * The CLKDM_MISSING_IDLE_REPORTING flag documentation has + * more details on the unpleasant problem this is working + * around + */ + if (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING && + !(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) { + _enable_hwsup(clkdm); + return 0; + } + hwsup = omap2_cm_is_clkdm_in_hwsup(clkdm->pwrdm.ptr->prcm_offs, clkdm->clktrctrl_mask); @@ -209,38 +263,6 @@ static int omap2_clkdm_clk_disable(struct clockdomain *clkdm) return 0; } -static int omap3_clkdm_sleep(struct clockdomain *clkdm) -{ - omap3xxx_cm_clkdm_force_sleep(clkdm->pwrdm.ptr->prcm_offs, - clkdm->clktrctrl_mask); - return 0; -} - -static int omap3_clkdm_wakeup(struct clockdomain *clkdm) -{ - omap3xxx_cm_clkdm_force_wakeup(clkdm->pwrdm.ptr->prcm_offs, - clkdm->clktrctrl_mask); - return 0; -} - -static void omap3_clkdm_allow_idle(struct clockdomain *clkdm) -{ - if (atomic_read(&clkdm->usecount) > 0) - _clkdm_add_autodeps(clkdm); - - omap3xxx_cm_clkdm_enable_hwsup(clkdm->pwrdm.ptr->prcm_offs, - clkdm->clktrctrl_mask); -} - -static void omap3_clkdm_deny_idle(struct clockdomain *clkdm) -{ - omap3xxx_cm_clkdm_disable_hwsup(clkdm->pwrdm.ptr->prcm_offs, - clkdm->clktrctrl_mask); - - if (atomic_read(&clkdm->usecount) > 0) - _clkdm_del_autodeps(clkdm); -} - struct clkdm_ops omap2_clkdm_operations = { .clkdm_add_wkdep = omap2_clkdm_add_wkdep, .clkdm_del_wkdep = omap2_clkdm_del_wkdep, diff --git a/arch/arm/mach-omap2/clockdomain44xx.c b/arch/arm/mach-omap2/clockdomain44xx.c index 762f2cc..6fc6155 100644 --- a/arch/arm/mach-omap2/clockdomain44xx.c +++ b/arch/arm/mach-omap2/clockdomain44xx.c @@ -113,6 +113,17 @@ static int omap4_clkdm_clk_disable(struct clockdomain *clkdm) if (!clkdm->prcm_partition) return 0; + /* + * The CLKDM_MISSING_IDLE_REPORTING flag documentation has + * more details on the unpleasant problem this is working + * around + */ + if (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING && + !(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) { + omap4_clkdm_allow_idle(clkdm); + return 0; + } + hwsup = omap4_cminst_is_clkdm_in_hwsup(clkdm->prcm_partition, clkdm->cm_inst, clkdm->clkdm_offs); diff --git a/arch/arm/mach-omap2/clockdomains3xxx_data.c b/arch/arm/mach-omap2/clockdomains3xxx_data.c index 56089c4..933a35c 100644 --- a/arch/arm/mach-omap2/clockdomains3xxx_data.c +++ b/arch/arm/mach-omap2/clockdomains3xxx_data.c @@ -387,14 +387,11 @@ static struct clockdomain per_am35x_clkdm = { .clktrctrl_mask = OMAP3430_CLKTRCTRL_PER_MASK, }; -/* - * Disable hw supervised mode for emu_clkdm, because emu_pwrdm is - * switched of even if sdti is in use - */ static struct clockdomain emu_clkdm = { .name = "emu_clkdm", .pwrdm = { .name = "emu_pwrdm" }, - .flags = /* CLKDM_CAN_ENABLE_AUTO | */CLKDM_CAN_SWSUP, + .flags = (CLKDM_CAN_ENABLE_AUTO | CLKDM_CAN_SWSUP | + CLKDM_MISSING_IDLE_REPORTING), .clktrctrl_mask = OMAP3430_CLKTRCTRL_EMU_MASK, }; diff --git a/arch/arm/mach-omap2/clockdomains44xx_data.c b/arch/arm/mach-omap2/clockdomains44xx_data.c index 63d60a7..b56d06b 100644 --- a/arch/arm/mach-omap2/clockdomains44xx_data.c +++ b/arch/arm/mach-omap2/clockdomains44xx_data.c @@ -390,7 +390,8 @@ static struct clockdomain emu_sys_44xx_clkdm = { .prcm_partition = OMAP4430_PRM_PARTITION, .cm_inst = OMAP4430_PRM_EMU_CM_INST, .clkdm_offs = OMAP4430_PRM_EMU_CM_EMU_CDOFFS, - .flags = CLKDM_CAN_ENABLE_AUTO | CLKDM_CAN_FORCE_WAKEUP, + .flags = (CLKDM_CAN_ENABLE_AUTO | CLKDM_CAN_FORCE_WAKEUP | + CLKDM_MISSING_IDLE_REPORTING), }; static struct clockdomain l3_dma_44xx_clkdm = { diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c index 6ca8e51..36f0603 100644 --- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -1857,7 +1857,8 @@ static int _enable(struct omap_hwmod *oh) * completely the module. The clockdomain can be set * in HW_AUTO only when the module become ready. */ - hwsup = clkdm_in_hwsup(oh->clkdm); + hwsup = clkdm_in_hwsup(oh->clkdm) && + !clkdm_missing_idle_reporting(oh->clkdm); r = clkdm_hwmod_enable(oh->clkdm, oh); if (r) { WARN(1, "omap_hwmod: %s: could not enable clockdomain %s: %d\n", -- 1.7.10 -- 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
