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Diffstat (limited to 'arch/arm/cpu/armv7/sunxi')
-rw-r--r--arch/arm/cpu/armv7/sunxi/dram.c41
1 files changed, 19 insertions, 22 deletions
diff --git a/arch/arm/cpu/armv7/sunxi/dram.c b/arch/arm/cpu/armv7/sunxi/dram.c
index be6750d880..0bbb10d5e3 100644
--- a/arch/arm/cpu/armv7/sunxi/dram.c
+++ b/arch/arm/cpu/armv7/sunxi/dram.c
@@ -434,20 +434,18 @@ static void dramc_clock_output_en(u32 on)
#endif
}
-static const u16 tRFC_table[2][6] = {
- /* 256Mb 512Mb 1Gb 2Gb 4Gb 8Gb */
- /* DDR2 75ns 105ns 127.5ns 195ns 327.5ns invalid */
- { 77, 108, 131, 200, 336, 336 },
- /* DDR3 invalid 90ns 110ns 160ns 300ns 350ns */
- { 93, 93, 113, 164, 308, 359 }
+/* tRFC in nanoseconds for different densities (from the DDR3 spec) */
+static const u16 tRFC_DDR3_table[6] = {
+ /* 256Mb 512Mb 1Gb 2Gb 4Gb 8Gb */
+ 90, 90, 110, 160, 300, 350
};
-static void dramc_set_autorefresh_cycle(u32 clk, u32 type, u32 density)
+static void dramc_set_autorefresh_cycle(u32 clk, u32 density)
{
struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
u32 tRFC, tREFI;
- tRFC = (tRFC_table[type][density] * clk + 1023) >> 10;
+ tRFC = (tRFC_DDR3_table[density] * clk + 999) / 1000;
tREFI = (7987 * clk) >> 10; /* <= 7.8us */
writel(DRAM_DRR_TREFI(tREFI) | DRAM_DRR_TRFC(tRFC), &dram->drr);
@@ -570,6 +568,13 @@ unsigned long dramc_init(struct dram_para *para)
if (!para)
return 0;
+ /*
+ * only single rank DDR3 is supported by this code even though the
+ * hardware can theoretically support DDR2 and up to two ranks
+ */
+ if (para->type != DRAM_MEMORY_TYPE_DDR3 || para->rank_num != 1)
+ return 0;
+
/* setup DRAM relative clock */
mctl_setup_dram_clock(para->clock, para->mbus_clock);
@@ -590,9 +595,7 @@ unsigned long dramc_init(struct dram_para *para)
mctl_enable_dll0(para->tpr3);
/* configure external DRAM */
- reg_val = 0x0;
- if (para->type == DRAM_MEMORY_TYPE_DDR3)
- reg_val |= DRAM_DCR_TYPE_DDR3;
+ reg_val = DRAM_DCR_TYPE_DDR3;
reg_val |= DRAM_DCR_IO_WIDTH(para->io_width >> 3);
if (para->density == 256)
@@ -632,25 +635,19 @@ unsigned long dramc_init(struct dram_para *para)
mctl_enable_dllx(para->tpr3);
/* set refresh period */
- dramc_set_autorefresh_cycle(para->clock, para->type - 2, density);
+ dramc_set_autorefresh_cycle(para->clock, density);
/* set timing parameters */
writel(para->tpr0, &dram->tpr0);
writel(para->tpr1, &dram->tpr1);
writel(para->tpr2, &dram->tpr2);
- if (para->type == DRAM_MEMORY_TYPE_DDR3) {
- reg_val = DRAM_MR_BURST_LENGTH(0x0);
+ reg_val = DRAM_MR_BURST_LENGTH(0x0);
#if (defined(CONFIG_SUN5I) || defined(CONFIG_SUN7I))
- reg_val |= DRAM_MR_POWER_DOWN;
+ reg_val |= DRAM_MR_POWER_DOWN;
#endif
- reg_val |= DRAM_MR_CAS_LAT(para->cas - 4);
- reg_val |= DRAM_MR_WRITE_RECOVERY(0x5);
- } else if (para->type == DRAM_MEMORY_TYPE_DDR2) {
- reg_val = DRAM_MR_BURST_LENGTH(0x2);
- reg_val |= DRAM_MR_CAS_LAT(para->cas);
- reg_val |= DRAM_MR_WRITE_RECOVERY(0x5);
- }
+ reg_val |= DRAM_MR_CAS_LAT(para->cas - 4);
+ reg_val |= DRAM_MR_WRITE_RECOVERY(0x5);
writel(reg_val, &dram->mr);
writel(para->emr1, &dram->emr);