From 085d4574c530e4b09fee654771fbea079e61b138 Mon Sep 17 00:00:00 2001 From: Christian Riesch Date: Tue, 8 Nov 2011 08:55:13 -0500 Subject: [PATCH] arm, davinci: Fix setting of the SDRAM configuration register da850_ddr_setup() expects the BOOTUNLOCK bit to be set in If BOOTUNLOCK is not set in this define, several configuration bits will not be writeable and the code will not work. Since the BOOTUNLOCK and TIMUNLOCK bits are not configuration options but access control bits, this patch changes the code to work irrespective of the value of these bits in CONFIG_SYS_DA850_DDR2_SDBCR. Signed-off-by: Christian Riesch Cc: Heiko Schocher Cc: Paulraj Sandeep Signed-off-by: Sandeep Paulraj --- .../cpu/arm926ejs/davinci/da850_lowlevel.c | 25 ++++++++++++++----- 1 file 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 490ef8fa33..327ff97a87 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! -- 2.25.1