[U-Boot] [PATCH v3 1/5] kirkwood: add save functionality kirkwood_mpp_conf function

[Valentin Longchamp]

If a second non NULL argument is given to the kirkwood_mpp_conf
function, it will be used to store the current configuration of the MPP
registers. mpp_save  must be a preallocated table of the same size as
mpp_list and it must be zero terminated as well.

A later call to kirkwood_mpp_conf function with this saved list as first
(mpp_conf) argment will set the configuration back.

Signed-off-by: Valentin Longchamp <valentin.longchamp at keymile.com>
cc: Holger Brunck <holger.brunck at keymile.com>
cc: Prafulla Wadaskar <prafulla at marvell.com>
---
 arch/arm/cpu/arm926ejs/kirkwood/mpp.c    |   14 ++++++++++++--
 arch/arm/include/asm/arch-kirkwood/mpp.h |    2 +-
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
index 3da6c98..158ea84 100644
--- a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
+++ b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
@@ -31,11 +31,11 @@ static u32 kirkwood_variant(void)
 #define MPP_CTRL(i)	(KW_MPP_BASE + (i* 4))
 #define MPP_NR_REGS	(1 + MPP_MAX/8)
 
-void kirkwood_mpp_conf(u32 *mpp_list)
+void kirkwood_mpp_conf(u32 *mpp_list, u32 *mpp_save)
 {
 	u32 mpp_ctrl[MPP_NR_REGS];
 	unsigned int variant_mask;
-	int i;
+	int i, save = 0;
 
 	variant_mask = kirkwood_variant();
 	if (!variant_mask)
@@ -48,10 +48,13 @@ void kirkwood_mpp_conf(u32 *mpp_list)
 	}
 	debug("\n");
 
+	if (mpp_save)
+		save = 1;
 
 	while (*mpp_list) {
 		unsigned int num = MPP_NUM(*mpp_list);
 		unsigned int sel = MPP_SEL(*mpp_list);
+		unsigned int sel_save;
 		int shift;
 
 		if (num > MPP_MAX) {
@@ -66,6 +69,13 @@ void kirkwood_mpp_conf(u32 *mpp_list)
 		}
 
 		shift = (num & 7) << 2;
+
+		if (save) {
+			sel_save = (mpp_ctrl[num / 8] >> shift) & 0xf;
+			*mpp_save = num | (sel_save << 8) | variant_mask;
+			mpp_save++;
+		}
+
 		mpp_ctrl[num / 8] &= ~(0xf << shift);
 		mpp_ctrl[num / 8] |= sel << shift;
 
diff --git a/arch/arm/include/asm/arch-kirkwood/mpp.h b/arch/arm/include/asm/arch-kirkwood/mpp.h
index b3c090e..8e50ee7 100644
--- a/arch/arm/include/asm/arch-kirkwood/mpp.h
+++ b/arch/arm/include/asm/arch-kirkwood/mpp.h
@@ -312,6 +312,6 @@
 
 #define MPP_MAX			49
 
-void kirkwood_mpp_conf(unsigned int *mpp_list);
+void kirkwood_mpp_conf(u32 *mpp_list, u32 *mpp_save);
 
 #endif
-- 
1.7.1