diff options
| author | York Sun <yorksun@freescale.com> | 2011-11-20 10:01:35 -0800 |
|---|---|---|
| committer | Kumar Gala <galak@kernel.crashing.org> | 2011-11-29 08:48:06 -0600 |
| commit | 4108508a96972e1200867666890d19fb63f76025 (patch) | |
| tree | 075274001cf896c4bc9208b978204fb2ac483cdd /arch/powerpc/cpu/mpc85xx/ddr-gen3.c | |
| parent | 33c875366e1d3e433881a86704816cdad847532f (diff) | |
powerpc/85xx: Add workaround for erratum A-003474
Erratum A-003474: Internal DDR calibration circuit is not supported
Impact:
Experience shows no significant benefit to device operation with
auto-calibration enabled versus it disabled. To ensure consistent timing
results, Freescale recommends this feature be disabled in future customer
products. There should be no impact to parts that are already operating
in the field.
Workaround:
Prior to setting DDR_SDRAM_CFG[MEM_EN]=1, do the following:
1. Write a value of 0x0000_0015 to the register at offset
CCSRBAR + DDR OFFSET + 0xf30
2. Write a value of 0x2400_0000 to the register at offset
CCSRBAR + DDR OFFSET + 0xf54
Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/cpu/mpc85xx/ddr-gen3.c')
| -rw-r--r-- | arch/powerpc/cpu/mpc85xx/ddr-gen3.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/mpc85xx/ddr-gen3.c b/arch/powerpc/cpu/mpc85xx/ddr-gen3.c index c8c84a1f7e..18e9cc5b8b 100644 --- a/arch/powerpc/cpu/mpc85xx/ddr-gen3.c +++ b/arch/powerpc/cpu/mpc85xx/ddr-gen3.c @@ -115,6 +115,11 @@ void fsl_ddr_set_memctl_regs(const fsl_ddr_cfg_regs_t *regs, for (i = 0; i < 32; i++) out_be32(&ddr->debug[i], regs->debug[i]); +#ifdef CONFIG_SYS_FSL_ERRATUM_DDR_A003474 + out_be32(&ddr->debug[12], 0x00000015); + out_be32(&ddr->debug[21], 0x24000000); +#endif /* CONFIG_SYS_FSL_ERRATUM_DDR_A003474 */ + /* Set, but do not enable the memory */ temp_sdram_cfg = regs->ddr_sdram_cfg; temp_sdram_cfg &= ~(SDRAM_CFG_MEM_EN); |