diff options
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/include/asm/arch-mx7/imx-regs.h | 1 | ||||
-rw-r--r-- | arch/arm/mach-imx/mx7/ddr.c | 22 |
2 files changed, 20 insertions, 3 deletions
diff --git a/arch/arm/include/asm/arch-mx7/imx-regs.h b/arch/arm/include/asm/arch-mx7/imx-regs.h index 95238dcaa8..f37419c07f 100644 --- a/arch/arm/include/asm/arch-mx7/imx-regs.h +++ b/arch/arm/include/asm/arch-mx7/imx-regs.h @@ -274,6 +274,7 @@ struct src { #define SRC_DDRC_RCR_DDRC_CORE_RST_OFFSET 1 #define SRC_DDRC_RCR_DDRC_CORE_RST_MASK (1 << 1) +#define SRC_DDRC_RCR_DDRC_PRST_MASK (1 << 0) /* GPR0 Bit Fields */ #define IOMUXC_GPR_GPR0_DMAREQ_MUX_SEL0_MASK 0x1u diff --git a/arch/arm/mach-imx/mx7/ddr.c b/arch/arm/mach-imx/mx7/ddr.c index 9713835bf2..d1e10a6788 100644 --- a/arch/arm/mach-imx/mx7/ddr.c +++ b/arch/arm/mach-imx/mx7/ddr.c @@ -13,6 +13,7 @@ #include <asm/arch/crm_regs.h> #include <asm/arch/mx7-ddr.h> #include <common.h> +#include <linux/delay.h> /* * Routine: mx7_dram_cfg @@ -37,8 +38,23 @@ void mx7_dram_cfg(struct ddrc *ddrc_regs_val, struct ddrc_mp *ddrc_mp_val, (struct iomuxc_gpr_base_regs *)IOMUXC_GPR_BASE_ADDR; int i; - /* Assert DDR Controller preset and DDR PHY reset */ - writel(SRC_DDRC_RCR_DDRC_CORE_RST_MASK, &src_regs->ddrc_rcr); + /* + * iMX7D RM 9.2.4.9.3 Power removal flow Table 9-11. Re-enabling power + * row 2 says "Reset controller / PHY by driving core_ddrc_rst = 0 , + * aresetn_n = 0, presetn = 0. That means reset everything. + */ + writel(SRC_DDRC_RCR_DDRC_CORE_RST_MASK | SRC_DDRC_RCR_DDRC_PRST_MASK, + &src_regs->ddrc_rcr); + + /* + * iMX7D RM 6.2.7.26 SRC_DDRC_RCR says wait 30 cycles (of unknown). + * If we assume this is 30 cycles at 100 MHz (about the rate of a + * DRAM bus), that's 300 nS, so waiting 10 uS is more then plenty. + */ + udelay(10); + + /* De-assert DDR Controller 'preset' and DDR PHY reset */ + clrbits_le32(&src_regs->ddrc_rcr, SRC_DDRC_RCR_DDRC_PRST_MASK); /* DDR controller configuration */ writel(ddrc_regs_val->mstr, &ddrc_regs->mstr); @@ -71,7 +87,7 @@ void mx7_dram_cfg(struct ddrc *ddrc_regs_val, struct ddrc_mp *ddrc_mp_val, writel(ddrc_regs_val->odtcfg, &ddrc_regs->odtcfg); writel(ddrc_regs_val->odtmap, &ddrc_regs->odtmap); - /* De-assert DDR Controller preset and DDR PHY reset */ + /* De-assert DDR Controller 'core_ddrc_rstn' and 'aresetn' */ clrbits_le32(&src_regs->ddrc_rcr, SRC_DDRC_RCR_DDRC_CORE_RST_MASK); /* PHY configuration */ |