[U-Boot] [PATCH v2 08/14] ARM: uniphier: fix glitch signal problem for low-level debug

[Masahiro Yamada]

Currently, IECTRL is enabled after pin-mux settings for the low-level
debugging for PH1-LD4 and PH1-sLD8.  While IECTRL is disabled, input
signals are pulled-down, i.e. glitch signal (Low to High transition)
problem occurs if pin-mux is set up first.  As a result, one invalid
character is input to the UART block and the auto-boot counting is
terminated immediately.

The correct initialization procedure is:
 [1] Enable IECTRL (if IECTRL exists for the pins)
 [2] Set up pin-muxing
 [3] Deassert the reset of the hardware block

Currently, the low-level debugging is working for PH1-sLD3 and
PH1-Pro4, but just in case, follow the sequence for all the SoCs.

Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
---

 arch/arm/mach-uniphier/ph1-ld4/lowlevel_debug.S  | 10 +++++-----
 arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S | 14 +++++++-------
 arch/arm/mach-uniphier/ph1-sld3/lowlevel_debug.S |  6 +++---
 arch/arm/mach-uniphier/ph1-sld8/lowlevel_debug.S | 10 +++++-----
 4 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/arch/arm/mach-uniphier/ph1-ld4/lowlevel_debug.S b/arch/arm/mach-uniphier/ph1-ld4/lowlevel_debug.S
index fd393dc..c0f14e0 100644
--- a/arch/arm/mach-uniphier/ph1-ld4/lowlevel_debug.S
+++ b/arch/arm/mach-uniphier/ph1-ld4/lowlevel_debug.S
@@ -14,16 +14,16 @@
 #include <mach/debug-uart.S>
 
 ENTRY(setup_lowlevel_debug)
-		init_debug_uart	r0, r1, r2
+		ldr		r0, =SG_IECTRL
+		ldr		r1, [r0]
+		orr		r1, r1, #1
+		str		r1, [r0]
 
 		/* UART Port 0 */
 		sg_set_pinsel	85, 1, 8, 4, r0, r1
 		sg_set_pinsel	88, 1, 8, 4, r0, r1
 
-		ldr		r0, =SG_IECTRL
-		ldr		r1, [r0]
-		orr		r1, r1, #1
-		str		r1, [r0]
+		init_debug_uart	r0, r1, r2
 
 		mov		pc, lr
 ENDPROC(setup_lowlevel_debug)
diff --git a/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S b/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S
index ce5dd4b..56f3851 100644
--- a/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S
+++ b/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S
@@ -15,13 +15,6 @@
 #include <mach/debug-uart.S>
 
 ENTRY(setup_lowlevel_debug)
-		ldr		r0, =SC_CLKCTRL
-		ldr		r1, [r0]
-		orr		r1, r1, #SC_CLKCTRL_CEN_PERI
-		str		r1, [r0]
-
-		init_debug_uart	r0, r1, r2
-
 		/* UART Port 0 */
 		sg_set_pinsel	127, 0, 4, 8, r0, r1
 		sg_set_pinsel	128, 0, 4, 8, r0, r1
@@ -30,5 +23,12 @@ ENTRY(setup_lowlevel_debug)
 		mov		r1, #1
 		str		r1, [r0]
 
+		ldr		r0, =SC_CLKCTRL
+		ldr		r1, [r0]
+		orr		r1, r1, #SC_CLKCTRL_CEN_PERI
+		str		r1, [r0]
+
+		init_debug_uart	r0, r1, r2
+
 		mov		pc, lr
 ENDPROC(setup_lowlevel_debug)
diff --git a/arch/arm/mach-uniphier/ph1-sld3/lowlevel_debug.S b/arch/arm/mach-uniphier/ph1-sld3/lowlevel_debug.S
index ee2eae6..f4eccb4 100644
--- a/arch/arm/mach-uniphier/ph1-sld3/lowlevel_debug.S
+++ b/arch/arm/mach-uniphier/ph1-sld3/lowlevel_debug.S
@@ -15,6 +15,9 @@
 #include <mach/debug-uart.S>
 
 ENTRY(setup_lowlevel_debug)
+		sg_set_pinsel	63, 0, 4, 4, r0, r1
+		sg_set_pinsel	64, 1, 4, 4, r0, r1
+
 		ldr		r0, =BCSCR5
 		ldr		r1, =0x24440000
 		str		r1, [r0]
@@ -26,8 +29,5 @@ ENTRY(setup_lowlevel_debug)
 
 		init_debug_uart	r0, r1, r2
 
-		sg_set_pinsel	63, 0, 4, 4, r0, r1
-		sg_set_pinsel	64, 1, 4, 4, r0, r1
-
 		mov		pc, lr
 ENDPROC(setup_lowlevel_debug)
diff --git a/arch/arm/mach-uniphier/ph1-sld8/lowlevel_debug.S b/arch/arm/mach-uniphier/ph1-sld8/lowlevel_debug.S
index 3ada4c9..571ce60 100644
--- a/arch/arm/mach-uniphier/ph1-sld8/lowlevel_debug.S
+++ b/arch/arm/mach-uniphier/ph1-sld8/lowlevel_debug.S
@@ -14,16 +14,16 @@
 #include <mach/debug-uart.S>
 
 ENTRY(setup_lowlevel_debug)
-		init_debug_uart	r0, r1, r2
+		ldr		r0, =SG_IECTRL
+		ldr		r1, [r0]
+		orr		r1, r1, #1
+		str		r1, [r0]
 
 		/* UART Port 0 */
 		sg_set_pinsel	70, 3, 8, 4, r0, r1
 		sg_set_pinsel	71, 3, 8, 4, r0, r1
 
-		ldr		r0, =SG_IECTRL
-		ldr		r1, [r0]
-		orr		r1, r1, #1
-		str		r1, [r0]
+		init_debug_uart	r0, r1, r2
 
 		mov		pc, lr
 ENDPROC(setup_lowlevel_debug)
-- 
1.9.1