[PATCH] drivers: ddr: lc_common_dimm_params.c : Fix Divison by zero issue

[Maninder Singh]

Adds check for memory clock variable before calculating caslat_actual.

Set mclk_ps to slowest DIMM supported if mclk_ps is found zero.

Signed-off-by: Maninder Singh <maninder.singh_1 at nxp.com>
---
 drivers/ddr/fsl/lc_common_dimm_params.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/ddr/fsl/lc_common_dimm_params.c b/drivers/ddr/fsl/lc_common_dimm_params.c
index d299d763db..d738ae3a7c 100644
--- a/drivers/ddr/fsl/lc_common_dimm_params.c
+++ b/drivers/ddr/fsl/lc_common_dimm_params.c
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright 2008-2016 Freescale Semiconductor, Inc.
- * Copyright 2017-2018 NXP Semiconductor
+ * Copyright 2017-2021 NXP Semiconductor
  */
 
 #include <common.h>
@@ -23,7 +23,7 @@ compute_cas_latency(const unsigned int ctrl_num,
 	unsigned int caslat_actual;
 	unsigned int retry = 16;
 	unsigned int tmp = ~0;
-	const unsigned int mclk_ps = get_memory_clk_period_ps(ctrl_num);
+	unsigned int mclk_ps = get_memory_clk_period_ps(ctrl_num);
 #ifdef CONFIG_SYS_FSL_DDR3
 	const unsigned int taamax = 20000;
 #else
@@ -37,6 +37,12 @@ compute_cas_latency(const unsigned int ctrl_num,
 	}
 	common_caslat = tmp;
 
+	if (!mclk_ps) {
+		printf("DDR clock (MCLK cycle was 0 ps), So setting it to slowest DIMM(s) (tCKmin %u ps).\n",
+		       outpdimm->tckmin_x_ps);
+		mclk_ps = outpdimm->tckmin_x_ps;
+	}
+
 	/* validate if the memory clk is in the range of dimms */
 	if (mclk_ps < outpdimm->tckmin_x_ps) {
 		printf("DDR clock (MCLK cycle %u ps) is faster than "
-- 
2.17.1