From 84baed2a2bdde3b2bf876d36cc966bd41ac67a6d Mon Sep 17 00:00:00 2001 From: York Sun Date: Fri, 7 Nov 2014 12:14:36 -0800 Subject: [PATCH] driver/ddr/fsl: Adjust timing_cfg_0 to better support two DDR slots Increase write-to-write and read-to-read turnaround time for two-slot DDR configurations. Previously only quad-rank and two dual-rank configurations have this additional turnaround time. A recent test on two single-rank DIMMs shows the shorter additional turnaround time is also needed. Signed-off-by: York Sun --- drivers/ddr/fsl/ctrl_regs.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/ddr/fsl/ctrl_regs.c b/drivers/ddr/fsl/ctrl_regs.c index 9e2a4d2f46..fe8aa98e8e 100644 --- a/drivers/ddr/fsl/ctrl_regs.c +++ b/drivers/ddr/fsl/ctrl_regs.c @@ -253,22 +253,30 @@ static void set_csn_config_2(int i, fsl_ddr_cfg_regs_t *ddr) /* -3E = 667 CL5, -25 = CL6 800, -25E = CL5 800 */ #if !defined(CONFIG_SYS_FSL_DDR1) +/* + * Check DIMM configuration, return 2 if quad-rank or two dual-rank + * Return 1 if other two slots configuration. Return 0 if single slot. + */ static inline int avoid_odt_overlap(const dimm_params_t *dimm_params) { #if CONFIG_DIMM_SLOTS_PER_CTLR == 1 if (dimm_params[0].n_ranks == 4) - return 1; + return 2; #endif #if CONFIG_DIMM_SLOTS_PER_CTLR == 2 if ((dimm_params[0].n_ranks == 2) && (dimm_params[1].n_ranks == 2)) - return 1; + return 2; #ifdef CONFIG_FSL_DDR_FIRST_SLOT_QUAD_CAPABLE if (dimm_params[0].n_ranks == 4) - return 1; + return 2; #endif + + if ((dimm_params[0].n_ranks != 0) && + (dimm_params[2].n_ranks != 0)) + return 1; #endif return 0; } @@ -316,6 +324,7 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr, #elif defined(CONFIG_SYS_FSL_DDR3) unsigned int data_rate = get_ddr_freq(0); int txp; + int odt_overlap; /* * (tXARD and tXARDS). Empirical? * The DDR3 spec has not tXARD, @@ -331,13 +340,23 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr, /* set the turnaround time */ /* - * for single quad-rank DIMM and two dual-rank DIMMs + * for single quad-rank DIMM and two-slot DIMMs * to avoid ODT overlap */ - if (avoid_odt_overlap(dimm_params)) { + odt_overlap = avoid_odt_overlap(dimm_params); + switch (odt_overlap) { + case 2: twwt_mclk = 2; trrt_mclk = 1; + break; + case 1: + twwt_mclk = 1; + trrt_mclk = 0; + break; + default: + break; } + /* for faster clock, need more time for data setup */ trwt_mclk = (data_rate/1000000 > 1800) ? 2 : 1; @@ -383,7 +402,7 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr, ); debug("FSLDDR: timing_cfg_0 = 0x%08x\n", ddr->timing_cfg_0); } -#endif /* defined(CONFIG_SYS_FSL_DDR2) */ +#endif /* !defined(CONFIG_SYS_FSL_DDR1) */ /* DDR SDRAM Timing Configuration 3 (TIMING_CFG_3) */ static void set_timing_cfg_3(fsl_ddr_cfg_regs_t *ddr, -- 2.25.1