[U-Boot] [PATCH 2/2] am43xx: Do not allow EMIF to control DDR_RESET in rtconly config

Keerthy j-keerthy at ti.com
Thu Mar 15 10:39:53 UTC 2018


From: Dave Gerlach <d-gerlach at ti.com>

Prevent EMIF control of DDR_RESET line on DDR3 am43xx platforms for
am43xx_evm_rtconly_config. Without this DDR is unstable and can become
corrupted after multiple iterations of RTC+DDR mode.

Signed-off-by: Dave Gerlach <d-gerlach at ti.com>
[j-keerthy at ti.com Ported to latest master branch]
Signed-off-by: Keerthy <j-keerthy at ti.com>
---
 arch/arm/mach-omap2/am33xx/emif4.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/mach-omap2/am33xx/emif4.c b/arch/arm/mach-omap2/am33xx/emif4.c
index 68c7705..54e11d3 100644
--- a/arch/arm/mach-omap2/am33xx/emif4.c
+++ b/arch/arm/mach-omap2/am33xx/emif4.c
@@ -95,8 +95,13 @@ void config_ddr(unsigned int pll, const struct ctrl_ioregs *ioregs,
 	writel(DDR_CKE_CTRL_NORMAL, &ddrctrl->ddrckectrl);
 
 	if (emif_sdram_type(regs->sdram_config) == EMIF_SDRAM_TYPE_DDR3)
+#ifndef CONFIG_SPL_RTC_ONLY_SUPPORT
 		/* Allow EMIF to control DDR_RESET */
 		writel(0x00000000, &ddrctrl->ddrioctrl);
+#else
+		/* Override EMIF DDR_RESET control */
+		writel(0x80000000, &ddrctrl->ddrioctrl);
+#endif /* CONFIG_SPL_RTC_ONLY_SUPPORT */
 #endif
 
 	/* Program EMIF instance */
-- 
1.9.1



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