From: Dave Liu daveliu@freescale.com
1. TIMING_CFG_0[ACT_PD_EXIT] was set to 6 clocks, but It should be set to tXP parameter, tXP=max(3CK, 7.5ns) 2. TIMING_CFG_0[PRE_PD_EXIT] was set to 6 clocks, but It should be set to tXP (if MR0[A12]=1) else to tXPDLL parameter We are setting the mode register MR0[A12]='1'
Signed-off-by: Dave Liu daveliu@freescale.com --- cpu/mpc8xxx/ddr/ctrl_regs.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/cpu/mpc8xxx/ddr/ctrl_regs.c b/cpu/mpc8xxx/ddr/ctrl_regs.c index 2505041..a92f1a3 100644 --- a/cpu/mpc8xxx/ddr/ctrl_regs.c +++ b/cpu/mpc8xxx/ddr/ctrl_regs.c @@ -188,12 +188,13 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr) * The DDR3 spec has not tXARD, * we use the tXP instead of it. * tXP=max(3nCK, 7.5ns) for DDR3. - * we use the tXP=6 * spec has not the tAXPD, we use * tAXPD=8, need design to confirm. */ - act_pd_exit_mclk = 6; - pre_pd_exit_mclk = 6; + int tXP = max((get_memory_clk_period_ps() * 3), 7500); /* unit=ps */ + act_pd_exit_mclk = picos_to_mclk(tXP); + /* Mode register MR0[A12] is '1' - fast exit */ + pre_pd_exit_mclk = act_pd_exit_mclk; taxpd_mclk = 8; tmrd_mclk = 4; #else /* CONFIG_FSL_DDR2 */