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>

4 files changed, 14 insertions, 8 deletions

diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c
index 4bfa650bb34..cf41ab55fa9 100644
--- a/arch/arm/mach-omap2/clock34xx.c
+++ b/arch/arm/mach-omap2/clock34xx.c
@@ -771,9 +771,9 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate)
 	/* REVISIT: SRAM code doesn't support other M2 divisors yet */
 	WARN_ON(new_div != 1 && new_div != 2);
 
-	/* REVISIT: Add SDRC_MR changing to this code also */
 	omap3_configure_core_dpll(sp->rfr_ctrl, sp->actim_ctrla,
-				  sp->actim_ctrlb, new_div, unlock_dll, c);
+				  sp->actim_ctrlb, new_div, unlock_dll, c,
+				  sp->mr);
 
 	return 0;
 }
diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S
index 8d4a88c3071..d13f1cc4bd5 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 @@ configure_sdrc:
 	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 @@ omap3_sdrc_actim_ctrla:
 	.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:
diff --git a/arch/arm/plat-omap/include/mach/sram.h b/arch/arm/plat-omap/include/mach/sram.h
index c32fa0a220d..4f87056a367 100644
--- a/arch/arm/plat-omap/include/mach/sram.h
+++ b/arch/arm/plat-omap/include/mach/sram.h
@@ -24,7 +24,7 @@ extern u32 omap2_set_prcm(u32 dpll_ctrl_val, u32 sdrc_rfr_val, int bypass);
 extern u32 omap3_configure_core_dpll(u32 sdrc_rfr_ctrl,
 				     u32 sdrc_actim_ctrla,
 				     u32 sdrc_actim_ctrlb, u32 m2,
-				     u32 unlock_dll, u32 f);
+				     u32 unlock_dll, u32 f, u32 sdrc_mr);
 
 /* Do not use these */
 extern void omap1_sram_reprogram_clock(u32 ckctl, u32 dpllctl);
@@ -62,7 +62,7 @@ extern unsigned long omap243x_sram_reprogram_sdrc_sz;
 extern u32 omap3_sram_configure_core_dpll(u32 sdrc_rfr_ctrl,
 					  u32 sdrc_actim_ctrla,
 					  u32 sdrc_actim_ctrlb, u32 m2,
-					  u32 unlock_dll, u32 f);
+					  u32 unlock_dll, u32 f, u32 sdrc_mr);
 extern unsigned long omap3_sram_configure_core_dpll_sz;
 
 #endif
diff --git a/arch/arm/plat-omap/sram.c b/arch/arm/plat-omap/sram.c
index 79c0f025442..7dadf1a59fb 100644
--- a/arch/arm/plat-omap/sram.c
+++ b/arch/arm/plat-omap/sram.c
@@ -372,16 +372,16 @@ static u32 (*_omap3_sram_configure_core_dpll)(u32 sdrc_rfr_ctrl,
 					      u32 sdrc_actim_ctrla,
 					      u32 sdrc_actim_ctrlb,
 					      u32 m2, u32 unlock_dll,
-					      u32 f);
+					      u32 f, u32 sdrc_mr);
 u32 omap3_configure_core_dpll(u32 sdrc_rfr_ctrl, u32 sdrc_actim_ctrla,
 			      u32 sdrc_actim_ctrlb, u32 m2, u32 unlock_dll,
-			      u32 f)
+			      u32 f, u32 sdrc_mr)
 {
 	BUG_ON(!_omap3_sram_configure_core_dpll);
 	return _omap3_sram_configure_core_dpll(sdrc_rfr_ctrl,
 					       sdrc_actim_ctrla,
 					       sdrc_actim_ctrlb, m2,
-					       unlock_dll, f);
+					       unlock_dll, f, sdrc_mr);
 }
 
 /* REVISIT: Should this be same as omap34xx_sram_init() after off-idle? */