From 23f9670f1aee936ca468d2d0ddb0f025defde626 Mon Sep 17 00:00:00 2001 From: York Sun Date: Fri, 27 May 2011 13:44:28 +0800 Subject: [PATCH] powerpc/mpc8xxx: Allow override DDR read-to-write turnaround time Add this option to allow boards to override the default read-to-write turnaround time for better performance. Signed-off-by: York Sun --- arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c | 3 +++ arch/powerpc/include/asm/fsl_ddr_sdram.h | 3 +++ 2 files changed, 6 insertions(+) diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c b/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c index 02d069c9ec..3824aade89 100644 --- a/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c +++ b/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c @@ -267,6 +267,9 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr, tmrd_mclk = 2; #endif + if (popts->trwt_override) + trwt_mclk = popts->trwt; + ddr->timing_cfg_0 = (0 | ((trwt_mclk & 0x3) << 30) /* RWT */ | ((twrt_mclk & 0x3) << 28) /* WRT */ diff --git a/arch/powerpc/include/asm/fsl_ddr_sdram.h b/arch/powerpc/include/asm/fsl_ddr_sdram.h index 1778cc56b6..bc063ea892 100644 --- a/arch/powerpc/include/asm/fsl_ddr_sdram.h +++ b/arch/powerpc/include/asm/fsl_ddr_sdram.h @@ -271,6 +271,9 @@ typedef struct memctl_options_s { unsigned int rcw_2; /* control register 1 */ unsigned int ddr_cdr1; + + unsigned int trwt_override; + unsigned int trwt; /* read-to-write turnaround */ } memctl_options_t; extern phys_size_t fsl_ddr_sdram(void); -- 2.39.5