[PATCH 32/41] ddr: imx8ulp: Update the ddr init flow

[Peng Fan (OSS)]

From: Jacky Bai <ping....@nxp.com>

Update the ddr init flow to support LPDDR3 and PLL bypass mode.

Reviewed-by: Ye Li <ye...@nxp.com>
Signed-off-by: Jacky Bai <ping....@nxp.com>
Signed-off-by: Peng Fan <peng....@nxp.com>
---
 drivers/ddr/imx/imx8ulp/ddr_init.c | 55 +++++++++++++++++++++++-------
 1 file changed, 43 insertions(+), 12 deletions(-)

diff --git a/drivers/ddr/imx/imx8ulp/ddr_init.c 
b/drivers/ddr/imx/imx8ulp/ddr_init.c
index a5a9fd8d7c8..3f04f533825 100644
--- a/drivers/ddr/imx/imx8ulp/ddr_init.c
+++ b/drivers/ddr/imx/imx8ulp/ddr_init.c
@@ -31,6 +31,7 @@
 #define DENALI_CTL_25          (DDR_CTL_BASE_ADDR + 4 * 25)
 
 #define DENALI_PHY_1624                (DDR_PHY_BASE_ADDR + 4 * 1624)
+#define DENALI_PHY_1625                (DDR_PHY_BASE_ADDR + 4 * 1625)
 #define DENALI_PHY_1537                (DDR_PHY_BASE_ADDR + 4 * 1537)
 #define PHY_FREQ_SEL_MULTICAST_EN(X)   ((X) << 8)
 #define PHY_FREQ_SEL_INDEX(X)          ((X) << 16)
@@ -82,25 +83,39 @@ int ddr_calibration(unsigned int fsp_table[3])
        u32 int_status_init, phy_freq_req, phy_freq_type;
        u32 lock_0, lock_1, lock_2;
        u32 freq_chg_pt, freq_chg_cnt;
+       u32 is_lpddr4 = 0;
 
        if (IS_ENABLED(CONFIG_IMX8ULP_DRAM_PHY_PLL_BYPASS)) {
                ddr_enable_pll_bypass();
                freq_chg_cnt = 0;
                freq_chg_pt = 0;
        } else {
-               reg_val = readl(DENALI_CTL_250);
-               if (((reg_val >> 16) & 0x3) == 1)
-                       freq_chg_cnt = 2;
-               else
-                       freq_chg_cnt = 3;
-
-               reg_val = readl(DENALI_PI_12);
-               if (reg_val == 0x3) {
-                       freq_chg_pt = 1;
-               } else if (reg_val == 0x7) {
-                       freq_chg_pt = 2;
+               reg_val = (readl(DENALI_CTL_00) >> 8) & 0xf;
+               if (reg_val == 0x7) {
+                       /* LPDDR3 type */
+                       set_ddr_clk(fsp_table[1] >> 1);
+                       freq_chg_cnt = 0;
+                       freq_chg_pt = 0;
+               } else if (reg_val == 0xb) {
+                       /* LPDDR4/4x type */
+                       is_lpddr4 = 1;
+                       reg_val = readl(DENALI_CTL_250);
+                       if (((reg_val >> 16) & 0x3) == 1)
+                               freq_chg_cnt = 2;
+                       else
+                               freq_chg_cnt = 3;
+
+                       reg_val = readl(DENALI_PI_12);
+                       if (reg_val == 0x3) {
+                               freq_chg_pt = 1;
+                       } else if (reg_val == 0x7) {
+                               freq_chg_pt = 2;
+                       } else {
+                               printf("frequency map(0x%x) is wrong, please 
check!\r\n", reg_val);
+                               return -1;
+                       }
                } else {
-                       printf("frequency map(0x%x) is wrong, please 
check!\r\n", reg_val);
+                       printf("Incorrect DDR type configured!\r\n");
                        return -1;
                }
        }
@@ -179,6 +194,22 @@ int ddr_calibration(unsigned int fsp_table[3])
        }
 
        debug("De-Skew PLL is locked and ready\n");
+
+       /* Change LPDDR4 FREQ1 to bypass mode if it is lower than 200MHz */
+       if (is_lpddr4 && fsp_table[1] < 400) {
+               /* Set FREQ1 to bypass mode */
+               reg_val = PHY_FREQ_SEL_MULTICAST_EN(0) | PHY_FREQ_SEL_INDEX(0);
+               writel(reg_val, DENALI_PHY_1537);
+
+               /* PHY_PLL_BYPASS=0x1 (DENALI_PHY_1624) */
+               reg_val = readl(DENALI_PHY_1624) | 0x1;
+               writel(reg_val, DENALI_PHY_1624);
+
+               /* DENALI_PHY_1625: bypass mode in PHY PLL */
+               reg_val = readl(DENALI_PHY_1625) & ~0xf;
+               writel(reg_val, DENALI_PHY_1625);
+       }
+
        return 0;
 }
 
-- 
2.36.0