In case four chip-selects are all active, the turnaround times need to increase to avoid overlapping under heavy load.
Signed-off-by: York Sun yorksun@freescale.com ---
drivers/ddr/fsl/ctrl_regs.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/ddr/fsl/ctrl_regs.c b/drivers/ddr/fsl/ctrl_regs.c index 99714bf..0bfcd34 100644 --- a/drivers/ddr/fsl/ctrl_regs.c +++ b/drivers/ddr/fsl/ctrl_regs.c @@ -317,7 +317,24 @@ static void set_timing_cfg_0(const unsigned int ctrl_num,
/* for faster clock, need more time for data setup */ trwt_mclk = (data_rate/1000000 > 1900) ? 3 : 2; - twrt_mclk = 1; + + /* + * for single quad-rank DIMM and two-slot DIMMs + * to avoid ODT overlap + */ + switch (avoid_odt_overlap(dimm_params)) { + case 2: + twrt_mclk = 2; + twwt_mclk = 2; + trrt_mclk = 2; + break; + default: + twrt_mclk = 1; + twwt_mclk = 1; + trrt_mclk = 0; + break; + } + act_pd_exit_mclk = picos_to_mclk(ctrl_num, txp); pre_pd_exit_mclk = act_pd_exit_mclk; /* @@ -1822,6 +1839,7 @@ static void set_timing_cfg_4(fsl_ddr_cfg_regs_t *ddr, unsigned int wrt = 0; /* Write-to-read turnaround for same CS */ unsigned int rrt = 0; /* Read-to-read turnaround for same CS */ unsigned int wwt = 0; /* Write-to-write turnaround for same CS */ + unsigned int trwt_mclk = 0; /* ext_rwt */ unsigned int dll_lock = 0; /* DDR SDRAM DLL Lock Time */
#if defined(CONFIG_SYS_FSL_DDR3) || defined(CONFIG_SYS_FSL_DDR4) @@ -1835,17 +1853,21 @@ static void set_timing_cfg_4(fsl_ddr_cfg_regs_t *ddr, wwt = 2; /* BL/2 + 2 clocks */ } #endif - #ifdef CONFIG_SYS_FSL_DDR4 dll_lock = 2; /* tDLLK = 1024 clocks */ #elif defined(CONFIG_SYS_FSL_DDR3) dll_lock = 1; /* tDLLK = 512 clocks from spec */ #endif + + if (popts->trwt_override) + trwt_mclk = popts->trwt; + ddr->timing_cfg_4 = (0 | ((rwt & 0xf) << 28) | ((wrt & 0xf) << 24) | ((rrt & 0xf) << 20) | ((wwt & 0xf) << 16) + | ((trwt_mclk & 0xc) << 12) | (dll_lock & 0x3) ); debug("FSLDDR: timing_cfg_4 = 0x%08x\n", ddr->timing_cfg_4);