From 413353b30b5d23c409b6a2fd70aa1cc28451a451 Mon Sep 17 00:00:00 2001
From: "maxims@google.com" <maxims@google.com>
Date: Mon, 17 Apr 2017 12:00:23 -0700
Subject: aspeed: Make SCU lock/unlock functions part of SCU API

Make functions for locking and unlocking SCU part of SCU API.
Many drivers need to modify settings in SCU and thus need to unlock it
first. This change makes it possible.

Signed-off-by: Maxim Sloyko <maxims@google.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---
 arch/arm/mach-aspeed/ast2500/clk_ast2500.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

(limited to 'arch/arm/mach-aspeed/ast2500/clk_ast2500.c')

diff --git a/arch/arm/mach-aspeed/ast2500/clk_ast2500.c b/arch/arm/mach-aspeed/ast2500/clk_ast2500.c
index 079909fa64..30cfac1af0 100644
--- a/arch/arm/mach-aspeed/ast2500/clk_ast2500.c
+++ b/arch/arm/mach-aspeed/ast2500/clk_ast2500.c
@@ -6,6 +6,7 @@
 
 #include <common.h>
 #include <dm.h>
+#include <asm/io.h>
 #include <asm/arch/scu_ast2500.h>
 
 int ast_get_clk(struct udevice **devp)
@@ -28,3 +29,17 @@ void *ast_get_scu(void)
 
 	return priv->scu;
 }
+
+void ast_scu_unlock(struct ast2500_scu *scu)
+{
+	writel(SCU_UNLOCK_VALUE, &scu->protection_key);
+	while (!readl(&scu->protection_key))
+		;
+}
+
+void ast_scu_lock(struct ast2500_scu *scu)
+{
+	writel(~SCU_UNLOCK_VALUE, &scu->protection_key);
+	while (readl(&scu->protection_key))
+		;
+}
-- 
cgit