From: Steve Kipisz s-kipisz2@ti.com
The original write to sdram_config is correct for DDR3 but incorrect for DDR2 so SPL was hanging. For DDR2, the write to sdram_config should be after the writes to ref_ctrl. This was working for DDR3 because there was a write of 0x2800 to ref_ctrl before a write to sdram_config.
Tested on: GP EVM 1.1A (DDR2), GP EVM 1.5A (DDR3), Beaglebone A6 (DDR2), Beagleone Blacd A4A (DDR3)
Signed-off-by: Steve Kipisz s-kipisz2@ti.com --- arch/arm/cpu/armv7/am33xx/ddr.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/arch/arm/cpu/armv7/am33xx/ddr.c b/arch/arm/cpu/armv7/am33xx/ddr.c index 448cc40..7932a39 100644 --- a/arch/arm/cpu/armv7/am33xx/ddr.c +++ b/arch/arm/cpu/armv7/am33xx/ddr.c @@ -54,10 +54,13 @@ void config_sdram(const struct emif_regs *regs) writel(0x2800, &emif_reg->emif_sdram_ref_ctrl); writel(regs->zq_config, &emif_reg->emif_zq_config); writel(regs->sdram_config, &cstat->secure_emif_sdram_config); + writel(regs->sdram_config, &emif_reg->emif_sdram_config); + writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl); + writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl_shdw); } - writel(regs->sdram_config, &emif_reg->emif_sdram_config); writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl); writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl_shdw); + writel(regs->sdram_config, &emif_reg->emif_sdram_config); }
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