diff options
Diffstat (limited to 'arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c')
-rw-r--r-- | arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c b/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c index 490ef8f..327ff97 100644 --- a/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c +++ b/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c @@ -184,18 +184,31 @@ int da850_ddr_setup(unsigned int freq) clrbits_le32(&davinci_syscfg1_regs->ddr_slew, (1 << DDR_SLEW_CMOSEN_BIT)); + /* + * SDRAM Configuration Register (SDCR): + * First set the BOOTUNLOCK bit to make configuration bits + * writeable. + */ setbits_le32(&dv_ddr2_regs_ctrl->sdbcr, DV_DDR_BOOTUNLOCK); - writel((CONFIG_SYS_DA850_DDR2_SDBCR & ~0xf0000000) | - (readl(&dv_ddr2_regs_ctrl->sdbcr) & 0xf0000000), /*rsv Bytes*/ - &dv_ddr2_regs_ctrl->sdbcr); - writel(CONFIG_SYS_DA850_DDR2_SDBCR2, &dv_ddr2_regs_ctrl->sdbcr2); + /* + * Write the new value of these bits and clear BOOTUNLOCK. + * At the same time, set the TIMUNLOCK bit to allow changing + * the timing registers + */ + tmp = CONFIG_SYS_DA850_DDR2_SDBCR; + tmp &= ~(0x1 << DV_DDR_SDCR_BOOTUNLOCK_SHIFT); + tmp |= (0x1 << DV_DDR_SDCR_TIMUNLOCK_SHIFT); + writel(tmp, &dv_ddr2_regs_ctrl->sdbcr); + /* write memory configuration and timing */ + writel(CONFIG_SYS_DA850_DDR2_SDBCR2, &dv_ddr2_regs_ctrl->sdbcr2); writel(CONFIG_SYS_DA850_DDR2_SDTIMR, &dv_ddr2_regs_ctrl->sdtimr); writel(CONFIG_SYS_DA850_DDR2_SDTIMR2, &dv_ddr2_regs_ctrl->sdtimr2); - clrbits_le32(&dv_ddr2_regs_ctrl->sdbcr, - (1 << DV_DDR_SDCR_TIMUNLOCK_SHIFT)); + /* clear the TIMUNLOCK bit and write the value of the CL field */ + tmp &= ~(0x1 << DV_DDR_SDCR_TIMUNLOCK_SHIFT); + writel(tmp, &dv_ddr2_regs_ctrl->sdbcr); /* * LPMODEN and MCLKSTOPEN must be set! |