[PATCH] ram: k3-ddrss: Set SDRAM_IDX using device private data, ddr_ram_size

[Santhosh Kumar K]

The SDRAM_IDX in DDRSS_V2A_CTL_REG describes the number of address bits
minus 16 that are used to determine the mask used to detect memory
rollover and prevent aliasing and false coherency issues.

Set SDRAM_IDX using the device private data, ddr_ram_size for K3 family
of SoCs.

Signed-off-by: Santhosh Kumar K <s-k6 at ti.com>
---

Tested on AM64x, AM62Ax, AM62Px.
Logs: https://gist.github.com/santhosh21/6dcdeb9a118c13732f858a1baca7dc4c

---
 drivers/ram/k3-ddrss/k3-ddrss.c | 32 +++++++++++++++++++++++++-------
 1 file changed, 25 insertions(+), 7 deletions(-)

diff --git a/drivers/ram/k3-ddrss/k3-ddrss.c b/drivers/ram/k3-ddrss/k3-ddrss.c
index 05ea61bbfe9a..ff87faf6a224 100644
--- a/drivers/ram/k3-ddrss/k3-ddrss.c
+++ b/drivers/ram/k3-ddrss/k3-ddrss.c
@@ -33,6 +33,12 @@
 #define DDRSS_V2A_CTL_REG			0x0020
 #define DDRSS_ECC_CTRL_REG			0x0120
 
+#define DDRSS_V2A_CTL_REG_SDRAM_IDX_CALC(x)	((ilog2(x) - 16) << 5)
+#define DDRSS_V2A_CTL_REG_SDRAM_IDX_MASK	(~(0x1F << 0x5))
+#define DDRSS_V2A_CTL_REG_REGION_IDX_MASK	(~(0X1F))
+#define DDRSS_V2A_CTL_REG_REGION_IDX_DEFAULT	0xF
+
+#define DDRSS_ECC_CTRL_REG_DEFAULT		0x0
 #define DDRSS_ECC_CTRL_REG_ECC_EN		BIT(0)
 #define DDRSS_ECC_CTRL_REG_RMW_EN		BIT(1)
 #define DDRSS_ECC_CTRL_REG_ECC_CK		BIT(2)
@@ -711,6 +717,22 @@ static void k3_ddrss_ddr_bank_base_size_calc(struct k3_ddrss_desc *ddrss)
 		ddrss->ddr_ram_size += ddrss->ddr_bank_size[bank];
 }
 
+static void k3_ddrss_ddr_reg_init(struct k3_ddrss_desc *ddrss)
+{
+	u32 v2a_ctl_reg, sdram_idx;
+
+	sdram_idx = DDRSS_V2A_CTL_REG_SDRAM_IDX_CALC(ddrss->ddr_ram_size);
+	v2a_ctl_reg = readl(ddrss->ddrss_ss_cfg + DDRSS_V2A_CTL_REG);
+	v2a_ctl_reg = (v2a_ctl_reg & DDRSS_V2A_CTL_REG_SDRAM_IDX_MASK) | sdram_idx;
+
+	if (IS_ENABLED(CONFIG_SOC_K3_AM642))
+		v2a_ctl_reg = (v2a_ctl_reg & DDRSS_V2A_CTL_REG_REGION_IDX_MASK) |
+			      DDRSS_V2A_CTL_REG_REGION_IDX_DEFAULT;
+
+	writel(v2a_ctl_reg, ddrss->ddrss_ss_cfg + DDRSS_V2A_CTL_REG);
+	writel(DDRSS_ECC_CTRL_REG_DEFAULT, ddrss->ddrss_ss_cfg + DDRSS_ECC_CTRL_REG);
+}
+
 static void k3_ddrss_lpddr4_ecc_calc_reserved_mem(struct k3_ddrss_desc *ddrss)
 {
 	fdtdec_setup_mem_size_base_lowest();
@@ -769,11 +791,9 @@ static int k3_ddrss_probe(struct udevice *dev)
 	if (ret)
 		return ret;
 
-#ifdef CONFIG_K3_AM64_DDRSS
-	/* AM64x supports only up to 2 GB SDRAM */
-	writel(0x000001EF, ddrss->ddrss_ss_cfg + DDRSS_V2A_CTL_REG);
-	writel(0x0, ddrss->ddrss_ss_cfg + DDRSS_ECC_CTRL_REG);
-#endif
+	k3_ddrss_ddr_bank_base_size_calc(ddrss);
+
+	k3_ddrss_ddr_reg_init(ddrss);
 
 	ddrss->driverdt = lpddr4_getinstance();
 
@@ -787,8 +807,6 @@ static int k3_ddrss_probe(struct udevice *dev)
 
 	k3_lpddr4_start(ddrss);
 
-	k3_ddrss_ddr_bank_base_size_calc(ddrss);
-
 	if (IS_ENABLED(CONFIG_K3_INLINE_ECC)) {
 		if (!ddrss->ddrss_ss_cfg) {
 			printf("%s: ss_cfg is required if ecc is enabled but not provided.",
-- 
2.34.1