[U-Boot] [PATCH 4/6] arm: mach-omap2: am33xx: Disable EMIF_DEVOFF immediately before hw leveling

Keerthy j-keerthy at ti.com
Fri Apr 12 06:38:18 UTC 2019


From: Brad Griffis <bgriffis at ti.com>

In case of RTC+DDR resume, need to restore EMIF context
before initiating hardware leveling.

Signed-off-by: Brad Griffis <bgriffis at ti.com>
Signed-off-by: Keerthy <j-keerthy at ti.com>
---
 arch/arm/mach-omap2/am33xx/board.c |  3 ---
 arch/arm/mach-omap2/am33xx/ddr.c   | 10 ++++++++++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-omap2/am33xx/board.c b/arch/arm/mach-omap2/am33xx/board.c
index fe7b8e1e55..5507348981 100644
--- a/arch/arm/mach-omap2/am33xx/board.c
+++ b/arch/arm/mach-omap2/am33xx/board.c
@@ -481,9 +481,6 @@ static void rtc_only(void)
 	rtc_only_prcm_init();
 	sdram_init();
 
-	/* Disable EMIF_DEVOFF for normal operation and to exit self-refresh */
-	writel(0, &prm_device->emif_ctrl);
-
 	/* Check EMIF4D_SDRAM_CONFIG[31:29] SDRAM_TYPE */
 	/* Only perform leveling if SDRAM_TYPE = 3 (DDR3) */
 	sdrc = readl(AM43XX_EMIF_BASE + AM43XX_SDRAM_CONFIG_OFFSET);
diff --git a/arch/arm/mach-omap2/am33xx/ddr.c b/arch/arm/mach-omap2/am33xx/ddr.c
index 5d947a68c3..e6e6ef8e9a 100644
--- a/arch/arm/mach-omap2/am33xx/ddr.c
+++ b/arch/arm/mach-omap2/am33xx/ddr.c
@@ -80,6 +80,9 @@ static void configure_mr(int nr, u32 cs)
  */
 void config_sdram_emif4d5(const struct emif_regs *regs, int nr)
 {
+	struct prm_device_inst *prm_device =
+			(struct prm_device_inst *)PRM_DEVICE_INST;
+
 	writel(0xA0, &emif_reg[nr]->emif_pwr_mgmt_ctrl);
 	writel(0xA0, &emif_reg[nr]->emif_pwr_mgmt_ctrl_shdw);
 	writel(regs->zq_config, &emif_reg[nr]->emif_zq_config);
@@ -126,6 +129,13 @@ void config_sdram_emif4d5(const struct emif_regs *regs, int nr)
 	writel(regs->ref_ctrl, &emif_reg[nr]->emif_sdram_ref_ctrl);
 	writel(regs->ref_ctrl, &emif_reg[nr]->emif_sdram_ref_ctrl_shdw);
 
+	/*
+	 * Disable EMIF_DEVOFF
+	 * -> Cold Boot: This is just rewriting the default register value.
+	 * -> RTC Resume: Must disable DEVOFF before leveling.
+	 */
+	writel(0, &prm_device->emif_ctrl);
+
 	/* Perform hardware leveling for DDR3 */
 	if (emif_sdram_type(regs->sdram_config) == EMIF_SDRAM_TYPE_DDR3) {
 		writel(readl(&emif_reg[nr]->emif_ddr_ext_phy_ctrl_36) |
-- 
2.17.1



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