diff options
| author | Haiying Wang | 2007-06-19 14:18:32 -0400 |
|---|---|---|
| committer | Andrew Fleming-AFLEMING | 2007-08-14 01:45:51 -0500 |
| commit | d111d6382c99fdea08c2312eeeae8786945e189a (patch) | |
| tree | 689badef14549bda5ac780242e9e2a6f8047a522 /cpu/mpc85xx | |
| parent | 3db0bef59eab1155801618cef5c481e97553b597 (diff) | |
Empirically set cpo and clk_adjust for mpc85xx DDR2 support
This patch is against u-boot-mpc85xx.git of www.denx.com
Setting cpo to 0x9 for frequencies higher than 333MHz is verified on
both MPC8548CDS board and MPC8568MDS board, especially for supporting
533MHz DDR2.
Setting clk_adjust to 0x6(3/4 late cycle) for MPC8568MDS board is for
DDR2 on all current board versions especially ver 1.92 or later to bring
up.
Signed-off-by: Haiying Wang <Haiying.Wang@freescale.com>
Diffstat (limited to 'cpu/mpc85xx')
| -rw-r--r-- | cpu/mpc85xx/spd_sdram.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/cpu/mpc85xx/spd_sdram.c b/cpu/mpc85xx/spd_sdram.c index 679f3608f72..5dc223a53e3 100644 --- a/cpu/mpc85xx/spd_sdram.c +++ b/cpu/mpc85xx/spd_sdram.c @@ -692,13 +692,10 @@ spd_sdram(void) */ cpo = 0; if (spd.mem_type == SPD_MEMTYPE_DDR2) { - if (effective_data_rate == 266 || effective_data_rate == 333) { + if (effective_data_rate <= 333) { cpo = 0x7; /* READ_LAT + 5/4 */ - } else if (effective_data_rate == 400) { - cpo = 0x9; /* READ_LAT + 7/4 */ } else { - /* Pure speculation */ - cpo = 0xb; + cpo = 0x9; /* READ_LAT + 7/4 */ } } @@ -905,7 +902,12 @@ spd_sdram(void) if (spd.mem_type == SPD_MEMTYPE_DDR) clk_adjust = 0x6; else +#ifdef CONFIG_MPC8568 + /* Empirally setting clk_adjust */ + clk_adjust = 0x6; +#else clk_adjust = 0x7; +#endif ddr->sdram_clk_cntl = (0 | 0x80000000 |