Re: [PATCH v4 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy
On Sat, Dec 18, 2010 at 11:53 PM, Nishanth Menon n...@ti.com wrote: From: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com Erratum i581 impacts OMAP3 platforms. PRCM DPLL control FSM removes SDRC_IDLEREQ before DPLL3 locks causing the DPLL not to be locked at times. IMPORTANT: *) This is not a complete workaround implementation as recommended by the silicon erratum. this is a support logic for detecting lockups and attempting to recover where possible and is known to provide stability in multiple platforms. *) This code is mostly important for inactive and retention. The ROM code waits for the maximum dll lock time when resuming from off mode. So for off mode this code isn't really needed. This should eventually get refactored as part of cleanups to sleep34xx.S Cc: Kevin Hilman khil...@deeprootsystems.com Cc: Tony Lindgren t...@atomide.com Signed-off-by: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com --- (no change done, posting for completeness of the series) v2: https://patchwork.kernel.org/patch/365252/ typo correction- erratum, support, added comment from Peter from the thread to commit message v1: http://marc.info/?l=linux-omapm=129013172525234w=2 arch/arm/mach-omap2/sleep34xx.S | 52 +++--- 1 files changed, 47 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S index 2c20fcf..3fbd1e5 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -42,6 +42,7 @@ OMAP3430_PM_PREPWSTST) #define PM_PWSTCTRL_MPU_P OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL #define CM_IDLEST1_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1) +#define CM_IDLEST_CKGEN_V OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST) #define SRAM_BASE_P 0x4020 #define CONTROL_STAT 0x480022F0 #define SCRATCHPAD_MEM_OFFS 0x310 /* Move this as correct place is @@ -554,31 +555,67 @@ skip_l2_inval: /* Make sure SDRC accesses are ok */ wait_sdrc_ok: + +/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this. */ + ldr r4, cm_idlest_ckgen +wait_dpll3_lock: + ldr r5, [r4] + tst r5, #1 + beq wait_dpll3_lock + ldr r4, cm_idlest1_core +wait_sdrc_ready: ldr r5, [r4] - and r5, r5, #0x2 - cmp r5, #0 - bne wait_sdrc_ok + tst r5, #0x2 + bne wait_sdrc_ready + /* allow DLL powerdown upon hw idle req */ ldr r4, sdrc_power ldr r5, [r4] bic r5, r5, #0x40 str r5, [r4] -wait_dll_lock: +is_dll_in_lock_mode: + /* Is dll in lock mode? */ ldr r4, sdrc_dlla_ctrl ldr r5, [r4] tst r5, #0x4 bxne lr /* wait till dll locks */ - ldr r4, sdrc_dlla_status +wait_dll_lock_timed: + ldr r4, wait_dll_lock_counter + add r4, r4, #1 + str r4, wait_dll_lock_counter + ldr r4, sdrc_dlla_status + mov r6, #8 /* Wait 20uS for lock */ +wait_dll_lock: + subs r6, r6, #0x1 + beq kick_dll It would be good to have more comments on the code flow here: - what are wait_dll_lock_counter and kick_counter used for? - what is the timing based on? Why 20uS for the wait time? - jumping back and forth to kick_dll and wait_dll_lock_timed is confusing. ldr r5, [r4] and r5, r5, #0x4 cmp r5, #0x4 bne wait_dll_lock bx lr + /* disable/reenable DLL if not locked */ +kick_dll: + ldr r4, sdrc_dlla_ctrl + ldr r5, [r4] + mov r6, r5 + bic r6, #(13) /* disable dll */ + str r6, [r4] + dsb + orr r6, r6, #(13) /* enable dll */ + str r6, [r4] + dsb + ldr r4, kick_counter + add r4, r4, #1 + str r4, kick_counter + b wait_dll_lock_timed + cm_idlest1_core: .word CM_IDLEST1_CORE_V +cm_idlest_ckgen: + .word CM_IDLEST_CKGEN_V sdrc_dlla_status: .word SDRC_DLLA_STATUS_V sdrc_dlla_ctrl: @@ -615,5 +652,10 @@ control_stat: .word CONTROL_STAT kernel_flush: .word v7_flush_dcache_all + /* these 2 words need to be at the end !!! */ +kick_counter: + .word 0 +wait_dll_lock_counter: + .word 0 Why do they need to be at the end? Also, at the end of what do they need to be? ENTRY(omap34xx_cpu_suspend_sz) .word . - omap34xx_cpu_suspend -- 1.6.3.3 Regards, Jean -- 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 v4 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy
On Mon, Dec 20, 2010 at 11:23:27AM +0100, ext Jean Pihet wrote: On Sat, Dec 18, 2010 at 11:53 PM, Nishanth Menon n...@ti.com wrote: From: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com Erratum i581 impacts OMAP3 platforms. PRCM DPLL control FSM removes SDRC_IDLEREQ before DPLL3 locks causing the DPLL not to be locked at times. IMPORTANT: *) This is not a complete workaround implementation as recommended by the silicon erratum. this is a support logic for detecting lockups and attempting to recover where possible and is known to provide stability in multiple platforms. *) This code is mostly important for inactive and retention. The ROM code waits for the maximum dll lock time when resuming from off mode. So for off mode this code isn't really needed. This should eventually get refactored as part of cleanups to sleep34xx.S Cc: Kevin Hilman khil...@deeprootsystems.com Cc: Tony Lindgren t...@atomide.com Signed-off-by: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com --- (no change done, posting for completeness of the series) v2: https://patchwork.kernel.org/patch/365252/ typo correction- erratum, support, added comment from Peter from the thread to commit message v1: http://marc.info/?l=linux-omapm=129013172525234w=2 arch/arm/mach-omap2/sleep34xx.S | 52 +++--- 1 files changed, 47 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S index 2c20fcf..3fbd1e5 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -42,6 +42,7 @@ OMAP3430_PM_PREPWSTST) #define PM_PWSTCTRL_MPU_P OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL #define CM_IDLEST1_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1) +#define CM_IDLEST_CKGEN_V OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST) #define SRAM_BASE_P 0x4020 #define CONTROL_STAT 0x480022F0 #define SCRATCHPAD_MEM_OFFS 0x310 /* Move this as correct place is @@ -554,31 +555,67 @@ skip_l2_inval: /* Make sure SDRC accesses are ok */ wait_sdrc_ok: + +/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this. */ + ldr r4, cm_idlest_ckgen +wait_dpll3_lock: + ldr r5, [r4] + tst r5, #1 + beq wait_dpll3_lock + ldr r4, cm_idlest1_core +wait_sdrc_ready: ldr r5, [r4] - and r5, r5, #0x2 - cmp r5, #0 - bne wait_sdrc_ok + tst r5, #0x2 + bne wait_sdrc_ready + /* allow DLL powerdown upon hw idle req */ ldr r4, sdrc_power ldr r5, [r4] bic r5, r5, #0x40 str r5, [r4] -wait_dll_lock: +is_dll_in_lock_mode: + /* Is dll in lock mode? */ ldr r4, sdrc_dlla_ctrl ldr r5, [r4] tst r5, #0x4 bxne lr /* wait till dll locks */ - ldr r4, sdrc_dlla_status +wait_dll_lock_timed: + ldr r4, wait_dll_lock_counter + add r4, r4, #1 + str r4, wait_dll_lock_counter + ldr r4, sdrc_dlla_status + mov r6, #8 /* Wait 20uS for lock */ +wait_dll_lock: + subs r6, r6, #0x1 + beq kick_dll It would be good to have more comments on the code flow here: - what are wait_dll_lock_counter and kick_counter used for? For debugging and statistics. So you can find out how many times a 'kick' was needed. - what is the timing based on? Why 20uS for the wait time? This is the maximum lock time of the dll according to TI for OMAP3430. - jumping back and forth to kick_dll and wait_dll_lock_timed is confusing. ldr r5, [r4] and r5, r5, #0x4 cmp r5, #0x4 bne wait_dll_lock bx lr + /* disable/reenable DLL if not locked */ +kick_dll: + ldr r4, sdrc_dlla_ctrl + ldr r5, [r4] + mov r6, r5 + bic r6, #(13) /* disable dll */ + str r6, [r4] + dsb + orr r6, r6, #(13) /* enable dll */ + str r6, [r4] + dsb + ldr r4, kick_counter + add r4, r4, #1 + str r4, kick_counter + b wait_dll_lock_timed + cm_idlest1_core: .word CM_IDLEST1_CORE_V +cm_idlest_ckgen: + .word CM_IDLEST_CKGEN_V sdrc_dlla_status: .word SDRC_DLLA_STATUS_V sdrc_dlla_ctrl: @@ -615,5 +652,10 @@ control_stat: .word CONTROL_STAT kernel_flush: .word v7_flush_dcache_all + /* these 2 words need to be at the end !!! */ +kick_counter: + .word 0 +wait_dll_lock_counter: + .word 0 Why do they need to be at the end? Also, at the end of
Re: [PATCH v4 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy
Santosh Shilimkar had written, on 12/20/2010 12:47 AM, the following: [..] diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach- omap2/sleep34xx.S index 2c20fcf..3fbd1e5 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -42,6 +42,7 @@ OMAP3430_PM_PREPWSTST) #define PM_PWSTCTRL_MPU_P OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL #define CM_IDLEST1_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1) +#define CM_IDLEST_CKGEN_V OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST) We need to avoid these macro's calculating VA directly. But I guess it needs to be done more than just this line and hence can be done in a separate patch. yes - with the cleanups planned for this file, we could probably add it to that set I guess. -- Regards, Nishanth Menon -- 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 v4 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy
Peter 'p2' De Schrijver had written, on 12/20/2010 05:33 AM, the following: [..] + /* these 2 words need to be at the end !!! */ +kick_counter: + .word 0 +wait_dll_lock_counter: + .word 0 Why do they need to be at the end? Also, at the end of what do they need to be? At the end of omap34xx_cpu_suspend. As we don't know where in SRAM the counters will be, the code accessing those counters addresses them relative from (_omap_sram_idle + omap34xx_cpu_suspend_sz). Not sure if this part of the code made it to linux-omap though. I have not posted the change needed to expose these counters to userspace waiting for the churn in sleep34xx.S to settle down. -- Regards, Nishanth Menon -- 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 v4 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy
-Original Message- From: linux-omap-ow...@vger.kernel.org [mailto:linux-omap- ow...@vger.kernel.org] 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 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy From: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com Erratum i581 impacts OMAP3 platforms. PRCM DPLL control FSM removes SDRC_IDLEREQ before DPLL3 locks causing the DPLL not to be locked at times. IMPORTANT: *) This is not a complete workaround implementation as recommended by the silicon erratum. this is a support logic for detecting lockups and attempting to recover where possible and is known to provide stability in multiple platforms. *) This code is mostly important for inactive and retention. The ROM code waits for the maximum dll lock time when resuming from off mode. So for off mode this code isn't really needed. This should eventually get refactored as part of cleanups to sleep34xx.S Cc: Kevin Hilman khil...@deeprootsystems.com Cc: Tony Lindgren t...@atomide.com Signed-off-by: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com --- (no change done, posting for completeness of the series) v2: https://patchwork.kernel.org/patch/365252/ typo correction- erratum, support, added comment from Peter from the thread to commit message v1: http://marc.info/?l=linux-omapm=129013172525234w=2 arch/arm/mach-omap2/sleep34xx.S | 52 +++--- 1 files changed, 47 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach- omap2/sleep34xx.S index 2c20fcf..3fbd1e5 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -42,6 +42,7 @@ OMAP3430_PM_PREPWSTST) #define PM_PWSTCTRL_MPU_POMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL #define CM_IDLEST1_CORE_VOMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1) +#define CM_IDLEST_CKGEN_VOMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST) We need to avoid these macro's calculating VA directly. But I guess it needs to be done more than just this line and hence can be done in a separate patch. #define SRAM_BASE_P 0x4020 #define CONTROL_STAT 0x480022F0 #define SCRATCHPAD_MEM_OFFS 0x310 /* Move this as correct place is @@ -554,31 +555,67 @@ skip_l2_inval: /* Make sure SDRC accesses are ok */ wait_sdrc_ok: + +/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this. */ + ldr r4, cm_idlest_ckgen +wait_dpll3_lock: + ldr r5, [r4] + tst r5, #1 + beq wait_dpll3_lock + ldr r4, cm_idlest1_core +wait_sdrc_ready: ldr r5, [r4] -and r5, r5, #0x2 -cmp r5, #0 -bne wait_sdrc_ok +tst r5, #0x2 +bne wait_sdrc_ready + /* allow DLL powerdown upon hw idle req */ ldr r4, sdrc_power ldr r5, [r4] bic r5, r5, #0x40 str r5, [r4] -wait_dll_lock: +is_dll_in_lock_mode: + /* Is dll in lock mode? */ ldr r4, sdrc_dlla_ctrl ldr r5, [r4] tst r5, #0x4 bxnelr /* wait till dll locks */ -ldr r4, sdrc_dlla_status +wait_dll_lock_timed: + ldr r4, wait_dll_lock_counter + add r4, r4, #1 + str r4, wait_dll_lock_counter + ldr r4, sdrc_dlla_status +mov r6, #8 /* Wait 20uS for lock */ +wait_dll_lock: + subsr6, r6, #0x1 + beq kick_dll ldr r5, [r4] and r5, r5, #0x4 cmp r5, #0x4 bne wait_dll_lock bx lr + /* disable/reenable DLL if not locked */ +kick_dll: + ldr r4, sdrc_dlla_ctrl + ldr r5, [r4] + mov r6, r5 + bic r6, #(13) /* disable dll */ + str r6, [r4] + dsb + orr r6, r6, #(13) /* enable dll */ + str r6, [r4] + dsb + ldr r4, kick_counter + add r4, r4, #1 + str r4, kick_counter + b wait_dll_lock_timed + cm_idlest1_core: .word CM_IDLEST1_CORE_V +cm_idlest_ckgen: + .word CM_IDLEST_CKGEN_V sdrc_dlla_status: .word SDRC_DLLA_STATUS_V sdrc_dlla_ctrl: @@ -615,5 +652,10 @@ control_stat: .word CONTROL_STAT kernel_flush: .word v7_flush_dcache_all + /* these 2 words need to be at the end !!! */ +kick_counter: + .word 0 +wait_dll_lock_counter: + .word 0 ENTRY(omap34xx_cpu_suspend_sz) .word . - omap34xx_cpu_suspend -- 1.6.3.3 -- 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
[PATCH v4 2/7] OMAP3: PM: Erratum i581 support: dll kick strategy
From: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com Erratum i581 impacts OMAP3 platforms. PRCM DPLL control FSM removes SDRC_IDLEREQ before DPLL3 locks causing the DPLL not to be locked at times. IMPORTANT: *) This is not a complete workaround implementation as recommended by the silicon erratum. this is a support logic for detecting lockups and attempting to recover where possible and is known to provide stability in multiple platforms. *) This code is mostly important for inactive and retention. The ROM code waits for the maximum dll lock time when resuming from off mode. So for off mode this code isn't really needed. This should eventually get refactored as part of cleanups to sleep34xx.S Cc: Kevin Hilman khil...@deeprootsystems.com Cc: Tony Lindgren t...@atomide.com Signed-off-by: Peter 'p2' De Schrijver peter.de-schrij...@nokia.com --- (no change done, posting for completeness of the series) v2: https://patchwork.kernel.org/patch/365252/ typo correction- erratum, support, added comment from Peter from the thread to commit message v1: http://marc.info/?l=linux-omapm=129013172525234w=2 arch/arm/mach-omap2/sleep34xx.S | 52 +++--- 1 files changed, 47 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S index 2c20fcf..3fbd1e5 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -42,6 +42,7 @@ OMAP3430_PM_PREPWSTST) #define PM_PWSTCTRL_MPU_P OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL #define CM_IDLEST1_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1) +#define CM_IDLEST_CKGEN_V OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST) #define SRAM_BASE_P0x4020 #define CONTROL_STAT 0x480022F0 #define SCRATCHPAD_MEM_OFFS0x310 /* Move this as correct place is @@ -554,31 +555,67 @@ skip_l2_inval: /* Make sure SDRC accesses are ok */ wait_sdrc_ok: + +/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this. */ + ldr r4, cm_idlest_ckgen +wait_dpll3_lock: + ldr r5, [r4] + tst r5, #1 + beq wait_dpll3_lock + ldr r4, cm_idlest1_core +wait_sdrc_ready: ldr r5, [r4] -and r5, r5, #0x2 -cmp r5, #0 -bne wait_sdrc_ok +tst r5, #0x2 +bne wait_sdrc_ready + /* allow DLL powerdown upon hw idle req */ ldr r4, sdrc_power ldr r5, [r4] bic r5, r5, #0x40 str r5, [r4] -wait_dll_lock: +is_dll_in_lock_mode: + /* Is dll in lock mode? */ ldr r4, sdrc_dlla_ctrl ldr r5, [r4] tst r5, #0x4 bxnelr /* wait till dll locks */ -ldr r4, sdrc_dlla_status +wait_dll_lock_timed: + ldr r4, wait_dll_lock_counter + add r4, r4, #1 + str r4, wait_dll_lock_counter + ldr r4, sdrc_dlla_status +movr6, #8 /* Wait 20uS for lock */ +wait_dll_lock: + subsr6, r6, #0x1 + beq kick_dll ldr r5, [r4] and r5, r5, #0x4 cmp r5, #0x4 bne wait_dll_lock bx lr + /* disable/reenable DLL if not locked */ +kick_dll: + ldr r4, sdrc_dlla_ctrl + ldr r5, [r4] + mov r6, r5 + bic r6, #(13) /* disable dll */ + str r6, [r4] + dsb + orr r6, r6, #(13) /* enable dll */ + str r6, [r4] + dsb + ldr r4, kick_counter + add r4, r4, #1 + str r4, kick_counter + b wait_dll_lock_timed + cm_idlest1_core: .word CM_IDLEST1_CORE_V +cm_idlest_ckgen: + .word CM_IDLEST_CKGEN_V sdrc_dlla_status: .word SDRC_DLLA_STATUS_V sdrc_dlla_ctrl: @@ -615,5 +652,10 @@ control_stat: .word CONTROL_STAT kernel_flush: .word v7_flush_dcache_all + /* these 2 words need to be at the end !!! */ +kick_counter: + .word 0 +wait_dll_lock_counter: + .word 0 ENTRY(omap34xx_cpu_suspend_sz) .word . - omap34xx_cpu_suspend -- 1.6.3.3 -- 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
