[U-Boot] am33xx evm: Update secure_emif_sdram_config during ddr init

Satyanarayana, Sandhya sandhya.satyanarayana at ti.com
Fri Aug 10 06:29:57 CEST 2012


This patch updates secure_emif_sdram_config with the
same value written to sdram_config during ddr3 initialization.

During suspend/resume, this value is copied into sdram_config.
With this, a write to sdram_config at the end of resume sequence
which triggers an init sequence can be avoided.

Without this register write in place, the DDR_RESET line goes
low for a few cycles during resume which is a violation of the
JEDEC spec.

Signed-off-by: Satyanarayana, Sandhya <sandhya.satyanarayana at ti.com>
---
:100644 100644 cffd4ab... fd9fc4a... M	arch/arm/cpu/armv7/am33xx/ddr.c
:100644 100644 de9ee91... 6cfbef7... M	arch/arm/include/asm/arch-am33xx/cpu.h
:100644 100644 8a4b248... 819ea65... M	arch/arm/include/asm/arch-am33xx/sys_proto.h
 arch/arm/cpu/armv7/am33xx/ddr.c              |    5 ++++-
 arch/arm/include/asm/arch-am33xx/cpu.h       |    2 ++
 arch/arm/include/asm/arch-am33xx/sys_proto.h |    1 +
 3 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/arch/arm/cpu/armv7/am33xx/ddr.c b/arch/arm/cpu/armv7/am33xx/ddr.c
index cffd4ab..fd9fc4a 100644
--- a/arch/arm/cpu/armv7/am33xx/ddr.c
+++ b/arch/arm/cpu/armv7/am33xx/ddr.c
@@ -17,6 +17,7 @@ http://www.ti.com/
 
 #include <asm/arch/cpu.h>
 #include <asm/arch/ddr_defs.h>
+#include <asm/arch/sys_proto.h>
 #include <asm/io.h>
 #include <asm/emif.h>
 
@@ -46,8 +47,10 @@ void config_sdram(const struct emif_regs *regs)
 {
 	writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl);
 	writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl_shdw);
-	if (regs->zq_config)
+	if (regs->zq_config){
 		writel(regs->zq_config, &emif_reg->emif_zq_config);
+		writel(regs->sdram_config, &cstat->secure_emif_sdram_config);
+	}
 	writel(regs->sdram_config, &emif_reg->emif_sdram_config);
 }
 
diff --git a/arch/arm/include/asm/arch-am33xx/cpu.h b/arch/arm/include/asm/arch-am33xx/cpu.h
index de9ee91..6cfbef7 100644
--- a/arch/arm/include/asm/arch-am33xx/cpu.h
+++ b/arch/arm/include/asm/arch-am33xx/cpu.h
@@ -234,6 +234,8 @@ struct vtp_reg {
 struct ctrl_stat {
 	unsigned int resv1[16];
 	unsigned int statusreg;		/* ofset 0x40 */
+	unsigned int resv2[51];
+	unsigned int secure_emif_sdram_config;	/* offset 0x0110 */
 };
 
 /* AM33XX GPIO registers */
diff --git a/arch/arm/include/asm/arch-am33xx/sys_proto.h b/arch/arm/include/asm/arch-am33xx/sys_proto.h
index 8a4b248..819ea65 100644
--- a/arch/arm/include/asm/arch-am33xx/sys_proto.h
+++ b/arch/arm/include/asm/arch-am33xx/sys_proto.h
@@ -46,6 +46,7 @@ u32 get_sysboot_value(void);
 int print_cpuinfo(void);
 #endif
 
+extern struct ctrl_stat *cstat;
 u32 get_device_type(void);
 void setup_clocks_for_console(void);
 void ddr_pll_config(unsigned int ddrpll_M);
-- 
1.7.1



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