[PATCH 07/16] soc: renesas: Add support to read LSI DEVID register

[Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>]

Add support for reading the LSI DEVID register which is present on
RZ/G2{L,LC,UL} SoC's.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
 drivers/soc/renesas/renesas-soc.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/renesas/renesas-soc.c b/drivers/soc/renesas/renesas-soc.c
index 0f8eff4a641a..d73389670eef 100644
--- a/drivers/soc/renesas/renesas-soc.c
+++ b/drivers/soc/renesas/renesas-soc.c
@@ -64,7 +64,7 @@ static const struct renesas_family fam_shmobile __initconst __maybe_unused = {
 
 struct renesas_soc {
 	const struct renesas_family *family;
-	u8 id;
+	u32 id;
 };
 
 static const struct renesas_soc soc_rz_a1h __initconst __maybe_unused = {
@@ -348,6 +348,25 @@ static int __init renesas_soc_init(void)
 		goto done;
 	}
 
+	np = of_find_compatible_node(NULL, NULL, "renesas,devid");
+	if (np) {
+		chipid = of_iomap(np, 0);
+		of_node_put(np);
+
+		if (chipid) {
+			product = readl(chipid);
+			iounmap(chipid);
+
+			if (soc->id && (product & 0xfffffff) != soc->id) {
+				pr_warn("SoC mismatch (product = 0x%x)\n",
+					product);
+				return -ENODEV;
+			}
+		}
+
+		goto done;
+	}
+
 	/* Try PRR first, then hardcoded fallback */
 	np = of_find_compatible_node(NULL, NULL, "renesas,prr");
 	if (np) {
-- 
2.17.1