OMAP3: add comments for low power code errata
Errata covered:
- 1.157 & 1.185
- i443
- i581
Tested on N900 and Beagleboard with full RET and OFF modes,
using cpuidle and suspend.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index a81ed25..c45b4fa 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -146,7 +146,7 @@
/*
* Force write last pad into memory, as this can fail in some
- * cases according to erratas 1.157, 1.185
+ * cases according to errata 1.157, 1.185
*/
omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14),
OMAP343X_CONTROL_MEM_WKUP + 0x2a0);
@@ -433,7 +433,7 @@
/*
* 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.
+ * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
* Hence store/restore the SDRC_POWER register here.
*/
if (omap_rev() >= OMAP3430_REV_ES3_0 &&
diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S
index 06e4732..17dfe30 100644
--- a/arch/arm/mach-omap2/sleep34xx.S
+++ b/arch/arm/mach-omap2/sleep34xx.S
@@ -596,6 +596,7 @@
* Internal functions
*/
+/* This function implements the erratum ID i443 WA, applies to 34xx >= ES3.0 */
.text
ENTRY(es3_sdrc_fix)
ldr r4, sdrc_syscfg @ get config addr
@@ -641,6 +642,16 @@
ENTRY(es3_sdrc_fix_sz)
.word . - es3_sdrc_fix
+/*
+ * This function implements the erratum ID i581 WA:
+ * SDRC state restore before accessing the SDRAM
+ *
+ * Only used at return from non-OFF mode. For OFF
+ * mode the ROM code configures the SDRC and
+ * the DPLL before calling the restore code directly
+ * from DDR.
+ */
+
/* Make sure SDRC accesses are ok */
wait_sdrc_ok: