[PATCH v1 4/5] ddr: altera: arria10: Add DRAM size checking

[alif.zakuan.yuslaimi at altera.com]

From: Alif Zakuan Yuslaimi <alif.zakuan.yuslaimi at altera.com>

Add DRAM size checking compare between size from device tree and actual
hardware.

Trigger hang if DRAM size from device tree is greater than actual hardware.
Display warning message if DRAM size mismatch between device tree and
actual hardware.

Signed-off-by: Alif Zakuan Yuslaimi <alif.zakuan.yuslaimi at altera.com>
---
 drivers/ddr/altera/sdram_arria10.c | 32 ++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/ddr/altera/sdram_arria10.c b/drivers/ddr/altera/sdram_arria10.c
index 0e3a1d42f34..d75c464f42a 100644
--- a/drivers/ddr/altera/sdram_arria10.c
+++ b/drivers/ddr/altera/sdram_arria10.c
@@ -8,6 +8,7 @@
 #include <fdtdec.h>
 #include <init.h>
 #include <log.h>
+#include <hang.h>
 #include <malloc.h>
 #include <wait_bit.h>
 #include <watchdog.h>
@@ -654,6 +655,22 @@ static int of_sdram_firewall_setup(const void *blob)
 	return 0;
 }
 
+static void sdram_size_check(void)
+{
+	phys_size_t ram_check = 0;
+
+	debug("DDR: Running SDRAM size sanity check\n");
+
+	ram_check = get_ram_size((long *)gd->bd->bi_dram[0].start,
+				 gd->bd->bi_dram[0].size);
+	if (ram_check != gd->bd->bi_dram[0].size) {
+		puts("DDR: SDRAM size check failed!\n");
+		hang();
+	}
+
+	debug("DDR: SDRAM size check passed!\n");
+}
+
 int ddr_calibration_sequence(void)
 {
 	schedule();
@@ -689,11 +706,26 @@ int ddr_calibration_sequence(void)
 	/* setup the dram info within bd */
 	dram_init_banksize();
 
+	if (gd->ram_size != gd->bd->bi_dram[0].size) {
+		printf("DDR: Warning: DRAM size from device tree (%ld MiB)\n",
+		       gd->bd->bi_dram[0].size >> 20);
+		printf(" mismatch with hardware (%ld MiB).\n",
+		       gd->ram_size >> 20);
+	}
+
+	if (gd->bd->bi_dram[0].size > gd->ram_size) {
+		printf("DDR: Error: DRAM size from device tree is greater\n");
+		printf(" than hardware size.\n");
+		hang();
+	}
+
 	if (of_sdram_firewall_setup(gd->fdt_blob))
 		puts("FW: Error Configuring Firewall\n");
 
 	if (sdram_is_ecc_enabled())
 		sdram_init_ecc_bits();
 
+	sdram_size_check();
+
 	return 0;
 }
-- 
2.43.7