OMAP3 clock/SDRC: program SDRC_MR register during SDRC clock change
Program the SDRC_MR_0 register as well during SDRC clock changes.
This register allows selection of the memory CAS latency. Some SDRAM
chips, such as the Qimonda HYB18M512160AF6, have a lower CAS latency
at lower clock rates.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S
index 8d4a88c..d13f1cc 100644
--- a/arch/arm/mach-omap2/sram34xx.S
+++ b/arch/arm/mach-omap2/sram34xx.S
@@ -44,12 +44,14 @@
* SDRC rates < 83MHz
* r5 = number of MPU cycles to wait for SDRC to stabilize after
* reprogramming the SDRC when switching to a slower MPU speed
+ * r6 = SDRC_MR_0 register value
*
*/
ENTRY(omap3_sram_configure_core_dpll)
stmfd sp!, {r1-r12, lr} @ store regs to stack
ldr r4, [sp, #52] @ pull extra args off the stack
ldr r5, [sp, #56] @ load extra args from the stack
+ ldr r6, [sp, #60] @ load extra args from the stack
dsb @ flush buffered writes to interconnect
cmp r3, #0x2
blne configure_sdrc
@@ -151,7 +153,9 @@
str r1, [r11]
ldr r11, omap3_sdrc_actim_ctrlb
str r2, [r11]
- ldr r2, [r11] @ posted-write barrier for SDRC
+ ldr r11, omap3_sdrc_mr_0
+ str r6, [r11]
+ ldr r6, [r11] @ posted-write barrier for SDRC
bx lr
omap3_sdrc_power:
@@ -168,6 +172,8 @@
.word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_A_0)
omap3_sdrc_actim_ctrlb:
.word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_B_0)
+omap3_sdrc_mr_0:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_MR_0)
omap3_sdrc_dlla_status:
.word OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS)
omap3_sdrc_dlla_ctrl:
