From d0ba3922ae241a87d22a1c3ffad72b96fe993c9a Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:27 -0600 Subject: 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 --- arch/arm/mach-omap2/sram34xx.S | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'arch/arm/mach-omap2/sram34xx.S') 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: -- cgit v1.2.3