powerpc/mpc8xxx: Fix DDR3 timing_cfg_1 and sdram_mode registers

The write recovery time of both registers should match. Since mode register
doesn't support cycles of 9,11,13,15, we should use next higher number for
both registers.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c b/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c
index 936c1951f65b9a8f7364ad420ab9361f0b16f28e..8ef6ca8c1c03e44067fedba2b9f12d079376b1fe 100644 (file)
--- a/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c
@@ -333,6 +333,9 @@ static void set_timing_cfg_1(fsl_ddr_cfg_regs_t *ddr,
        unsigned char acttoact_mclk;
        /* Last write data pair to read command issue interval (tWTR) */
        unsigned char wrtord_mclk;
+       /* DDR_SDRAM_MODE doesn't support 9,11,13,15 */
+       static const u8 wrrec_table[] = {
+               1, 2, 3, 4, 5, 6, 7, 8, 10, 10, 12, 12, 14, 14, 0, 0};
 
        pretoact_mclk = picos_to_mclk(common_dimm->tRP_ps);
        acttopre_mclk = picos_to_mclk(common_dimm->tRAS_ps);
@@ -371,6 +374,8 @@ static void set_timing_cfg_1(fsl_ddr_cfg_regs_t *ddr,
 
        refrec_ctrl = picos_to_mclk(common_dimm->tRFC_ps) - 8;
        wrrec_mclk = picos_to_mclk(common_dimm->tWR_ps);
+
+       wrrec_mclk = wrrec_table[wrrec_mclk - 1];
        if (popts->OTF_burst_chop_en)
                wrrec_mclk += 2;
 
@@ -810,6 +815,12 @@ static void set_ddr_sdram_mode(fsl_ddr_cfg_regs_t *ddr,
        unsigned int bl;        /* BL: Burst Length */
 
        unsigned int wr_mclk;
+       /*
+        * DDR_SDRAM_MODE doesn't support 9,11,13,15
+        * Please refer JEDEC Standard No. 79-3E for Mode Register MR0
+        * for this table
+        */
+       static const u8 wr_table[] = {1, 2, 3, 4, 5, 5, 6, 6, 7, 7, 0, 0};
 
        const unsigned int mclk_ps = get_memory_clk_period_ps();
        int i;
@@ -853,13 +864,10 @@ static void set_ddr_sdram_mode(fsl_ddr_cfg_regs_t *ddr,
         * 1=fast exit DLL on (tXP)
         */
        dll_on = 1;
+
        wr_mclk = (common_dimm->tWR_ps + mclk_ps - 1) / mclk_ps;
-       if (wr_mclk >= 12)
-               wr = 6;
-       else if (wr_mclk >= 9)
-               wr = 5;
-       else
-               wr = wr_mclk - 4;
+       wr = wr_table[wr_mclk - 5];
+
        dll_rst = 0;    /* dll no reset */
        mode = 0;       /* normal mode */