imx8ulp:ddr: saving the dram config timing data into sram

On i.MX8ULP, The dram config timing need to be saved into sram for
ddr retention when APD enter PD mode, so add this support on i.MX8ULP.

Reviewed-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>

2 files changed, 52 insertions, 0 deletions

diff --git a/drivers/ddr/imx/imx8ulp/Kconfig b/drivers/ddr/imx/imx8ulp/Kconfig
index e56062a1d03..42848863aae 100644
--- a/drivers/ddr/imx/imx8ulp/Kconfig
+++ b/drivers/ddr/imx/imx8ulp/Kconfig
@@ -8,4 +8,11 @@ config IMX8ULP_DRAM_PHY_PLL_BYPASS
 	bool "Enable the DDR PHY PLL bypass mode, so PHY clock is from DDR_CLK "
 	depends on IMX8ULP_DRAM
 
+config SAVED_DRAM_TIMING_BASE
+	hex "Define the base address for saved dram timing"
+	help
+	  The DRAM config timing data need to be saved into sram
+	  for low power use.
+	default 0x2006c000
+
 endmenu
diff --git a/drivers/ddr/imx/imx8ulp/ddr_init.c b/drivers/ddr/imx/imx8ulp/ddr_init.c
index 16aaf56103d..9730dd64508 100644
--- a/drivers/ddr/imx/imx8ulp/ddr_init.c
+++ b/drivers/ddr/imx/imx8ulp/ddr_init.c
@@ -178,6 +178,48 @@ int ddr_calibration(unsigned int fsp_table[3])
 	return 0;
 }
 
+static void save_dram_config(struct dram_timing_info2 *timing_info, unsigned long saved_timing_base)
+{
+	int i = 0;
+	struct dram_timing_info2 *saved_timing = (struct dram_timing_info2 *)saved_timing_base;
+	struct dram_cfg_param *cfg;
+
+	saved_timing->ctl_cfg_num = timing_info->ctl_cfg_num;
+	saved_timing->phy_f1_cfg_num = timing_info->phy_f1_cfg_num;
+	saved_timing->phy_f2_cfg_num = timing_info->phy_f2_cfg_num;
+
+	/* save the fsp table */
+	for (i = 0; i < 3; i++)
+		saved_timing->fsp_table[i] = timing_info->fsp_table[i];
+
+	cfg = (struct dram_cfg_param *)(saved_timing_base +
+					sizeof(*timing_info));
+
+	/* save ctl config */
+	saved_timing->ctl_cfg = cfg;
+	for (i = 0; i < timing_info->ctl_cfg_num; i++) {
+		cfg->reg = timing_info->ctl_cfg[i].reg;
+		cfg->val = timing_info->ctl_cfg[i].val;
+		cfg++;
+	}
+
+	/* save phy f1 config */
+	saved_timing->phy_f1_cfg = cfg;
+	for (i = 0; i < timing_info->phy_f1_cfg_num; i++) {
+		cfg->reg = timing_info->phy_f1_cfg[i].reg;
+		cfg->val = timing_info->phy_f1_cfg[i].val;
+		cfg++;
+	}
+
+	/* save phy f2 config */
+	saved_timing->phy_f2_cfg = cfg;
+	for (i = 0; i < timing_info->phy_f2_cfg_num; i++) {
+		cfg->reg = timing_info->phy_f2_cfg[i].reg;
+		cfg->val = timing_info->phy_f2_cfg[i].val;
+		cfg++;
+	}
+}
+
 int ddr_init(struct dram_timing_info2 *dram_timing)
 {
 	int i;
@@ -192,6 +234,9 @@ int ddr_init(struct dram_timing_info2 *dram_timing)
 		clrbits_le32(AVD_SIM_BASE_ADDR, 0x1); /* SIM_DDR_CTRL_DIV2_EN */
 	}
 
+	/* save the dram config into sram for low power mode */
+	save_dram_config(dram_timing, CONFIG_SAVED_DRAM_TIMING_BASE);
+
 	/* Initialize CTL registers */
 	for (i = 0; i < dram_timing->ctl_cfg_num; i++)
 		writel(dram_timing->ctl_cfg[i].val, (ulong)dram_timing->ctl_cfg[i].reg);