Kevin Hilman had written, on 12/13/2010 09:28 PM, the following:
Nishanth Menon <nm@xxxxxx> writes:
Erratum id: i608
RTA (Retention Till Access) feature is not supported and leads to device
stability issues when enabled. This impacts modules with embedded memories
on OMAP3630
Workaround is to disable RTA on boot and coming out of core off.
For disabling rta coming out of off mode, we do this by overriding the
restore pointer for 3630 to allow us restore handler as the first point of
entry before caches are touched and is common for GP and HS devices.
to disable earlier than this could be possible by modifying the ppa for HS
devices, but not for GP devices.
Cc: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
Cc: Tony Lindgren <tony@xxxxxxxxxxx>
[ambresh@xxxxxx: co-developer]
Signed-off-by: Ambresh K <ambresh@xxxxxx>
Signed-off-by: Nishanth Menon <nm@xxxxxx>
[...]
@@ -1045,6 +1057,15 @@ static int __init omap3_pm_init(void)
pm_idle = omap3_pm_idle;
omap3_idle_init();
+ /*
+ * RTA is disabled during initialization as per erratum i608
+ * it is safer to disable rta by the bootloader, but we would like
+ * to be doubly sure here and prevent any mishaps.
+ */
+ if (IS_PM34XX_ERRATUM(RTA_ERRATUM_i608))
+ omap_ctrl_writel(OMAP36XX_RTA_DISABLE,
+ OMAP36XX_CONTROL_MEM_RTA_CTRL);
+
Minor nit: we've been trying to clean up control module access. So,
rather than directly writing control module registers, could you create
an API for this like was done for omap3_ctrl_write_boot_mode().
looks like the cleanups are somewhere in -next and not in k.org tree.
basing the change similar to
http://marc.info/?l=linux-omap&m=129168623011464&w=2 does the
attached(based on 2.6.37-rc5) looks like how you'd like to see it? If i
need to rebase to any particular tree which already has this change
instead of k.org, do let me know.
--
Regards,
Nishanth Menon
>From 5cf295fa3fe8d423323500fb8ddb49650f797edd Mon Sep 17 00:00:00 2001
From: Nishanth Menon <nm@xxxxxx>
Date: Mon, 6 Sep 2010 10:26:08 +0530
Subject: [PATCH] OMAP3630: PM: Erratum i608: disable RTA
Erratum id: i608
RTA (Retention Till Access) feature is not supported and leads to device
stability issues when enabled. This impacts modules with embedded memories
on OMAP3630
Workaround is to disable RTA on boot and coming out of core off.
For disabling rta coming out of off mode, we do this by overriding the
restore pointer for 3630 to allow us restore handler as the first point of
entry before caches are touched and is common for GP and HS devices.
to disable earlier than this could be possible by modifying the ppa for HS
devices, but not for GP devices.
Signed-off-by: Ambresh K <ambresh@xxxxxx>
Signed-off-by: Nishanth Menon <nm@xxxxxx>
---
arch/arm/mach-omap2/control.c | 13 ++++++++++++-
arch/arm/mach-omap2/control.h | 7 ++++++-
arch/arm/mach-omap2/pm34xx.c | 20 ++++++++++++++++++++
arch/arm/mach-omap2/sleep34xx.S | 26 ++++++++++++++++++++++++++
4 files changed, 64 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-omap2/control.c b/arch/arm/mach-omap2/control.c
index 1fa3294..7c415bc 100644
--- a/arch/arm/mach-omap2/control.c
+++ b/arch/arm/mach-omap2/control.c
@@ -241,7 +241,10 @@ void omap3_save_scratchpad_contents(void)
/* Populate the Scratchpad contents */
scratchpad_contents.boot_config_ptr = 0x0;
- if (omap_rev() != OMAP3430_REV_ES3_0 &&
+ if (cpu_is_omap3630())
+ scratchpad_contents.public_restore_ptr =
+ virt_to_phys(get_omap3630_restore_pointer());
+ else if (omap_rev() != OMAP3430_REV_ES3_0 &&
omap_rev() != OMAP3430_REV_ES3_1)
scratchpad_contents.public_restore_ptr =
virt_to_phys(get_restore_pointer());
@@ -474,4 +477,12 @@ void omap3_control_restore_context(void)
omap_ctrl_writel(control_context.csi, OMAP343X_CONTROL_CSI);
return;
}
+
+void omap3630_disable_rta(void)
+{
+ if (!cpu_is_omap36xx())
+ return;
+ omap_ctrl_writel(OMAP36XX_RTA_DISABLE, OMAP36XX_CONTROL_MEM_RTA_CTRL);
+}
+
#endif /* CONFIG_ARCH_OMAP3 && CONFIG_PM */
diff --git a/arch/arm/mach-omap2/control.h b/arch/arm/mach-omap2/control.h
index b6c6b7c..13771cc 100644
--- a/arch/arm/mach-omap2/control.h
+++ b/arch/arm/mach-omap2/control.h
@@ -204,6 +204,10 @@
#define OMAP343X_CONTROL_WKUP_DEBOBS3 (OMAP343X_CONTROL_GENERAL_WKUP + 0x014)
#define OMAP343X_CONTROL_WKUP_DEBOBS4 (OMAP343X_CONTROL_GENERAL_WKUP + 0x018)
+/* 36xx-only RTA - Retention till Accesss control registers and bits */
+#define OMAP36XX_CONTROL_MEM_RTA_CTRL 0x40C
+#define OMAP36XX_RTA_DISABLE 0x0
+
/* 34xx D2D idle-related pins, handled by PM core */
#define OMAP3_PADCONF_SAD2D_MSTANDBY 0x250
#define OMAP3_PADCONF_SAD2D_IDLEACK 0x254
@@ -347,10 +351,11 @@ extern void omap3_save_scratchpad_contents(void);
extern void omap3_clear_scratchpad_contents(void);
extern u32 *get_restore_pointer(void);
extern u32 *get_es3_restore_pointer(void);
+extern u32 *get_omap3630_restore_pointer(void);
extern u32 omap3_arm_context[128];
extern void omap3_control_save_context(void);
extern void omap3_control_restore_context(void);
-
+extern void omap3630_disable_rta(void);
#else
#define omap_ctrl_base_get() 0
#define omap_ctrl_readb(x) 0
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 0ec8a04..859c452 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -55,6 +55,10 @@
#define OMAP343X_TABLE_VALUE_OFFSET 0xc0
#define OMAP343X_CONTROL_REG_VALUE_OFFSET 0xc8
+#define RTA_ERRATUM_i608 (1 << 0)
+static u16 pm34xx_errata;
+#define IS_PM34XX_ERRATUM(id) (pm34xx_errata & (id))
+
struct power_state {
struct powerdomain *pwrdm;
u32 next_state;
@@ -989,6 +993,12 @@ void omap_push_sram_idle(void)
save_secure_ram_context_sz);
}
+static void __init pm_errata_configure(void)
+{
+ if (cpu_is_omap3630())
+ pm34xx_errata |= RTA_ERRATUM_i608;
+}
+
static int __init omap3_pm_init(void)
{
struct power_state *pwrst, *tmp;
@@ -998,6 +1008,8 @@ static int __init omap3_pm_init(void)
if (!cpu_is_omap34xx())
return -ENODEV;
+ pm_errata_configure();
+
printk(KERN_ERR "Power Management for TI OMAP3.\n");
/* XXX prcm_setup_regs needs to be before enabling hw
@@ -1045,6 +1057,14 @@ static int __init omap3_pm_init(void)
pm_idle = omap3_pm_idle;
omap3_idle_init();
+ /*
+ * RTA is disabled during initialization as per erratum i608
+ * it is safer to disable rta by the bootloader, but we would like
+ * to be doubly sure here and prevent any mishaps.
+ */
+ if (IS_PM34XX_ERRATUM(RTA_ERRATUM_i608))
+ omap3630_disable_rta();
+
clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
omap3_secure_ram_storage =
diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S
index 3fbd1e5..cc3507b 100644
--- a/arch/arm/mach-omap2/sleep34xx.S
+++ b/arch/arm/mach-omap2/sleep34xx.S
@@ -45,6 +45,8 @@
#define CM_IDLEST_CKGEN_V OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST)
#define SRAM_BASE_P 0x40200000
#define CONTROL_STAT 0x480022F0
+#define CONTROL_MEM_RTA_CTRL (OMAP343X_CTRL_BASE\
+ + OMAP36XX_CONTROL_MEM_RTA_CTRL)
#define SCRATCHPAD_MEM_OFFS 0x310 /* Move this as correct place is
* available */
#define SCRATCHPAD_BASE_P (OMAP343X_CTRL_BASE + OMAP343X_CONTROL_MEM_WKUP\
@@ -99,6 +101,14 @@ ENTRY(get_restore_pointer)
ldmfd sp!, {pc} @ restore regs and return
ENTRY(get_restore_pointer_sz)
.word . - get_restore_pointer
+ .text
+/* Function call to get the restore pointer for 3630 resume from OFF */
+ENTRY(get_omap3630_restore_pointer)
+ stmfd sp!, {lr} @ save registers on stack
+ adr r0, restore_3630
+ ldmfd sp!, {pc} @ restore regs and return
+ENTRY(get_omap3630_restore_pointer_sz)
+ .word . - get_omap3630_restore_pointer
.text
/* Function call to get the restore pointer for for ES3 to resume from OFF */
@@ -246,6 +256,20 @@ copy_to_sram:
bne copy_to_sram
ldr r1, sram_base
blx r1
+ b restore
+
+restore_3630:
+ /*b restore_es3630*/ @ Enable to debug restore code
+ ldr r1, pm_prepwstst_core_p
+ ldr r2, [r1]
+ and r2, r2, #0x3
+ cmp r2, #0x0 @ Check if previous power state of CORE is OFF
+ bne restore
+ /* Disable rta before giving control */
+ ldr r1, control_mem_rta
+ mov r2, #OMAP36XX_RTA_DISABLE
+ str r2, [r1]
+ /* Fall thru for the remaining logic */
restore:
/* b restore*/ @ Enable to debug restore code
/* Check what was the reason for mpu reset and store the reason in r9*/
@@ -650,6 +674,8 @@ cache_pred_disable_mask:
.word 0xFFFFE7FB
control_stat:
.word CONTROL_STAT
+control_mem_rta:
+ .word CONTROL_MEM_RTA_CTRL
kernel_flush:
.word v7_flush_dcache_all
/* these 2 words need to be at the end !!! */
--
1.6.3.3
