[v2 11/17] ddr: socfpga: Enable memory test on memory size less than 1GB

[Siew Chin Lim]

From: Tien Fong Chee <tien.fong.chee at intel.com>

Minimum 1GB memory size is required in current memory test, so this patch
improves the memory test for processing memory size less than 1GB, and
the size in power of two.

Signed-off-by: Tien Fong Chee <tien.fong.chee at intel.com>

---
v2:
- Renamed local variable “total_size” to “remaining_size”
---
 drivers/ddr/altera/sdram_soc64.c | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/drivers/ddr/altera/sdram_soc64.c b/drivers/ddr/altera/sdram_soc64.c
index a08f0953e5..cc656db97c 100644
--- a/drivers/ddr/altera/sdram_soc64.c
+++ b/drivers/ddr/altera/sdram_soc64.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (C) 2016-2019 Intel Corporation <www.intel.com>
+ * Copyright (C) 2016-2021 Intel Corporation <www.intel.com>
  *
  */
 
@@ -182,6 +182,7 @@ void sdram_size_check(struct bd_info *bd)
 	phys_size_t total_ram_check = 0;
 	phys_size_t ram_check = 0;
 	phys_addr_t start = 0;
+	phys_size_t size, remaining_size;
 	int bank;
 
 	/* Sanity check ensure correct SDRAM size specified */
@@ -189,10 +190,27 @@ void sdram_size_check(struct bd_info *bd)
 
 	for (bank = 0; bank < CONFIG_NR_DRAM_BANKS; bank++) {
 		start = bd->bi_dram[bank].start;
+		remaining_size = bd->bi_dram[bank].size;
 		while (ram_check < bd->bi_dram[bank].size) {
-			ram_check += get_ram_size((void *)(start + ram_check),
-						 (phys_size_t)SZ_1G);
+			size = min((phys_addr_t)SZ_1G,
+				   (phys_addr_t)remaining_size);
+
+			/*
+			 * Ensure the size is power of two, this is requirement
+			 * to run get_ram_size() / memory test
+			 */
+			if (size != 0 && ((size & (size - 1)) == 0)) {
+				ram_check += get_ram_size((void *)
+						(start + ram_check), size);
+				remaining_size = bd->bi_dram[bank].size -
+							ram_check;
+			} else {
+				puts("DDR: Memory test requires SDRAM size ");
+				puts("in power of two!\n");
+				hang();
+			}
 		}
+
 		total_ram_check += ram_check;
 		ram_check = 0;
 	}
-- 
2.19.0