drivers/ddr/fsl: Enable detection of one DDR controller operation for LSCH3

Freescale LSCH3 platforms use two DDR controlers interleaving mode out of
reset. It can be configured to disable one controller. To support this
operation, the driver needs to detect and skip the disabled controller.

Signed-off-by: York Sun <yorksun@freescale.com>

2 files changed, 41 insertions, 0 deletions

diff --git a/drivers/ddr/fsl/main.c b/drivers/ddr/fsl/main.c
index 72ec1be65d..c68663220d 100644
--- a/drivers/ddr/fsl/main.c
+++ b/drivers/ddr/fsl/main.c
@@ -813,6 +813,7 @@ phys_size_t fsl_ddr_sdram(void)
 	info.board_need_mem_reset = board_need_mem_reset;
 	info.board_mem_reset = board_assert_mem_reset;
 	info.board_mem_de_reset = board_deassert_mem_reset;
+	remove_unused_controllers(&info);
 
 	return __fsl_ddr_sdram(&info);
 }
diff --git a/drivers/ddr/fsl/util.c b/drivers/ddr/fsl/util.c
index ce55aea1b4..1a49b28f33 100644
--- a/drivers/ddr/fsl/util.c
+++ b/drivers/ddr/fsl/util.c
@@ -385,3 +385,43 @@ void fsl_ddr_sync_memctl_refresh(unsigned int first_ctrl,
 		ddr_out32(ddrc_debug2_p[i], ddrc_debug2[i]);
 }
 #endif /* CONFIG_FSL_DDR_SYNC_REFRESH */
+
+void remove_unused_controllers(fsl_ddr_info_t *info)
+{
+#ifdef CONFIG_FSL_LSCH3
+	int i;
+	u64 nodeid;
+	void *hnf_sam_ctrl = (void *)(CCI_HN_F_0_BASE + CCN_HN_F_SAM_CTL);
+	bool ddr0_used = false;
+	bool ddr1_used = false;
+
+	for (i = 0; i < 8; i++) {
+		nodeid = in_le64(hnf_sam_ctrl) & CCN_HN_F_SAM_NODEID_MASK;
+		if (nodeid == CCN_HN_F_SAM_NODEID_DDR0) {
+			ddr0_used = true;
+		} else if (nodeid == CCN_HN_F_SAM_NODEID_DDR1) {
+			ddr1_used = true;
+		} else {
+			printf("Unknown nodeid in HN-F SAM control: 0x%llx\n",
+			       nodeid);
+		}
+		hnf_sam_ctrl += (CCI_HN_F_1_BASE - CCI_HN_F_0_BASE);
+	}
+	if (!ddr0_used && !ddr1_used) {
+		printf("Invalid configuration in HN-F SAM control\n");
+		return;
+	}
+
+	if (!ddr0_used && info->first_ctrl == 0) {
+		info->first_ctrl = 1;
+		info->num_ctrls = 1;
+		debug("First DDR controller disabled\n");
+		return;
+	}
+
+	if (!ddr1_used && info->first_ctrl + info->num_ctrls > 1) {
+		info->num_ctrls = 1;
+		debug("Second DDR controller disabled\n");
+	}
+#endif
+}