[PATCH 1/2] ddr: imx8m: write fsp_table entry automatically

[Marco Felsch <m.felsch@pengutronix.de>]

Currently the fsp_table must be set manually within the 'struct
dram_timing_info'. Since the 'struct fsp_msg' already has all
information needed for the fsp_table we can use it to set it
automatically. This approach is less error-prone and avoids information
duplication.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/ddr/imx8m/ddrphy_train.c |  3 +++
 drivers/ddr/imx8m/helper.c       | 19 +++++++++++++++++++
 include/soc/imx8m/ddr.h          |  2 ++
 3 files changed, 24 insertions(+)

diff --git a/drivers/ddr/imx8m/ddrphy_train.c b/drivers/ddr/imx8m/ddrphy_train.c
index e9d35afdfb..09f1e77295 100644
--- a/drivers/ddr/imx8m/ddrphy_train.c
+++ b/drivers/ddr/imx8m/ddrphy_train.c
@@ -165,6 +165,9 @@ int ddr_cfg_phy(struct dram_timing_info *dram_timing, unsigned type)
 
 		dwc_ddrphy_apb_wr(0xd0000, 0x1);
 
+		/* Training done, add entry to fsp_table */
+		dram_write_fsp_table_entry(dram_timing, fsp_msg->drate);
+
 		fsp_msg++;
 	}
 
diff --git a/drivers/ddr/imx8m/helper.c b/drivers/ddr/imx8m/helper.c
index 98e4084958..e71401c1b2 100644
--- a/drivers/ddr/imx8m/helper.c
+++ b/drivers/ddr/imx8m/helper.c
@@ -18,6 +18,25 @@
 #define DMEM_OFFSET_ADDR 0x00054000
 #define DDR_TRAIN_CODE_BASE_ADDR IP2APB_DDRPHY_IPS_BASE_ADDR(0)
 
+void dram_write_fsp_table_entry(struct dram_timing_info *timing_info,
+				unsigned int data_rate)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(timing_info->fsp_table); i++) {
+		unsigned int entry = timing_info->fsp_table[i];
+
+		/* Skip already existing entries */
+		if (entry == data_rate)
+			return;
+
+		if (entry == 0) {
+			timing_info->fsp_table[i] = data_rate;
+			return;
+		}
+	}
+}
+
 void ddrphy_trained_csr_save(struct dram_cfg_param *ddrphy_csr,
 			     unsigned int num)
 {
diff --git a/include/soc/imx8m/ddr.h b/include/soc/imx8m/ddr.h
index 2149ae4325..222ab8e0f4 100644
--- a/include/soc/imx8m/ddr.h
+++ b/include/soc/imx8m/ddr.h
@@ -436,6 +436,8 @@ int ddr_cfg_phy(struct dram_timing_info *timing_info, enum ddrc_type ddrc_type);
 void load_lpddr4_phy_pie(void);
 void ddrphy_trained_csr_save(struct dram_cfg_param *param, unsigned int num);
 void dram_config_save(struct dram_timing_info *info, unsigned long base);
+void dram_write_fsp_table_entry(struct dram_timing_info *timing_info,
+				unsigned int data_rate);
 
 /* utils function for ddr phy training */
 int wait_ddrphy_training_complete(void);
-- 
2.30.2