From ea4e97a511483dfd61b1417f935a7ed97e5565f9 Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Fri, 6 Dec 2019 21:42:11 -0700
Subject: [PATCH] x86: Set the DRAM banks to reflect real location

At present with fsp a single DRAM bank is added which extends to the
whole size of memory. However there is typically only 2GB of memory
available below the 4GB boundary, and this is what is used by U-Boot while
running in 32-bit mode.

Scan the tables to set the banks correct. The first bank is set to memory
below 4GB, and the rest of memory is put into subsequent banks.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
---
 arch/x86/lib/fsp/fsp_dram.c | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/arch/x86/lib/fsp/fsp_dram.c b/arch/x86/lib/fsp/fsp_dram.c
index bc456bb4a9..987cb4f8f3 100644
--- a/arch/x86/lib/fsp/fsp_dram.c
+++ b/arch/x86/lib/fsp/fsp_dram.c
@@ -38,8 +38,36 @@ int fsp_scan_for_ram_size(void)
 
 int dram_init_banksize(void)
 {
+	const struct hob_header *hdr;
+	struct hob_res_desc *res_desc;
+	phys_addr_t low_end;
+	uint bank;
+
+	low_end = 0;
+	for (bank = 1, hdr = gd->arch.hob_list;
+	     bank < CONFIG_NR_DRAM_BANKS && !end_of_hob(hdr);
+	     hdr = get_next_hob(hdr)) {
+		if (hdr->type != HOB_TYPE_RES_DESC)
+			continue;
+		res_desc = (struct hob_res_desc *)hdr;
+		if (res_desc->type != RES_SYS_MEM &&
+		    res_desc->type != RES_MEM_RESERVED)
+			continue;
+		if (res_desc->phys_start < (1ULL << 32)) {
+			low_end = max(low_end,
+				      res_desc->phys_start + res_desc->len);
+			continue;
+		}
+
+		gd->bd->bi_dram[bank].start = res_desc->phys_start;
+		gd->bd->bi_dram[bank].size = res_desc->len;
+		log_debug("ram %llx %llx\n", gd->bd->bi_dram[bank].start,
+			  gd->bd->bi_dram[bank].size);
+	}
+
+	/* Add the memory below 4GB */
 	gd->bd->bi_dram[0].start = 0;
-	gd->bd->bi_dram[0].size = gd->ram_size;
+	gd->bd->bi_dram[0].size = low_end;
 
 	return 0;
 }
-- 
2.39.5