[RFC: PATCH 4/4] AM335X: Add low level debugging support

[hvaibhav at ti.com]

From: Afzal Mohammed <afzal at ti.com>

Add support for low level debugging on AM335X EVM. Currently only
support for UART1 console, which is used on AM335X EVM is added.

Signed-off-by: Afzal Mohammed <afzal at ti.com>
Signed-off-by: Vaibhav Hiremath <hvaibhav at ti.com>
---
 arch/arm/mach-omap2/include/mach/debug-macro.S |   21 +++++++++++++++++++++
 arch/arm/plat-omap/include/plat/serial.h       |    4 ++++
 arch/arm/plat-omap/include/plat/uncompress.h   |    6 ++++++
 3 files changed, 31 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-omap2/include/mach/debug-macro.S b/arch/arm/mach-omap2/include/mach/debug-macro.S
index 309e328..a99ddbd 100644
--- a/arch/arm/mach-omap2/include/mach/debug-macro.S
+++ b/arch/arm/mach-omap2/include/mach/debug-macro.S
@@ -78,6 +78,8 @@ omap_uart_lsr:	.word	0
 		beq	82f			@ configure UART2
 		cmp	\rp, #TI81XXUART3	@ ti81Xx UART offsets different
 		beq	83f			@ configure UART3
+		cmp	\rp, #AM335XUART1	@ AM335X UART offsets different
+		beq	84f			@ configure UART1
 		cmp	\rp, #ZOOM_UART		@ only on zoom2/3
 		beq	95f			@ configure ZOOM_UART

@@ -106,6 +108,8 @@ omap_uart_lsr:	.word	0
 		b	98f
 83:		mov	\rp, #UART_OFFSET(TI81XX_UART3_BASE)
 		b	98f
+84:		mov	\rp, #UART_OFFSET(AM335X_UART1_BASE)
+		b	97f
 95:		ldr	\rp, =ZOOM_UART_BASE
 		mrc	p15, 0, \rv, c1, c0
 		tst	\rv, #1			@ MMU enabled?
@@ -121,6 +125,23 @@ omap_uart_lsr:	.word	0
 		b	10b

 		/* Store both phys and virt address for the uart */
+97:		add	\rp, \rp, #0x44000000	@ phys base
+		mrc	p15, 0, \rv, c1, c0
+		tst	\rv, #1			@ MMU enabled?
+		ldreq	\rv, =omap_uart_v2p(omap_uart_phys)	@ MMU disabled
+		ldrne	\rv, =omap_uart_phys	@ MMU enabled
+		str	\rp, [\rv, #0]
+		sub	\rp, \rp, #0x44000000	@ phys base
+		add	\rp, \rp, #0xf9000000	@ virt base
+		add	\rv, \rv, #4		@ omap_uart_virt
+		str	\rp, [\rv, #0]
+		mov	\rp, #(UART_LSR << OMAP_PORT_SHIFT)
+		add	\rv, \rv, #4		@ omap_uart_lsr
+		str	\rp, [\rv, #0]
+
+		b	10b
+
+		/* Store both phys and virt address for the uart */
 98:		add	\rp, \rp, #0x48000000	@ phys base
 		mrc	p15, 0, \rv, c1, c0
 		tst	\rv, #1			@ MMU enabled?
diff --git a/arch/arm/plat-omap/include/plat/serial.h b/arch/arm/plat-omap/include/plat/serial.h
index 865b13e..d7c1216 100644
--- a/arch/arm/plat-omap/include/plat/serial.h
+++ b/arch/arm/plat-omap/include/plat/serial.h
@@ -59,6 +59,9 @@
 /* AM3505/3517 UART4 */
 #define AM35XX_UART4_BASE	0x4809E000	/* Only on AM3505/3517 */

+/* AM335X serial port */
+#define AM335X_UART1_BASE	0x44E09000
+
 /* External port on Zoom2/3 */
 #define ZOOM_UART_BASE		0x10000000
 #define ZOOM_UART_VIRT		0xfa400000
@@ -92,6 +95,7 @@
 #define TI81XXUART1		81
 #define TI81XXUART2		82
 #define TI81XXUART3		83
+#define AM335XUART1		84
 #define ZOOM_UART		95		/* Only on zoom2/3 */

 /* This is only used by 8250.c for omap1510 */
diff --git a/arch/arm/plat-omap/include/plat/uncompress.h b/arch/arm/plat-omap/include/plat/uncompress.h
index 8d052e7..3592ce4 100644
--- a/arch/arm/plat-omap/include/plat/uncompress.h
+++ b/arch/arm/plat-omap/include/plat/uncompress.h
@@ -97,6 +97,10 @@ static inline void flush(void)
 	_DEBUG_LL_ENTRY(mach, TI81XX_UART##p##_BASE, OMAP_PORT_SHIFT,	\
 		TI81XXUART##p)

+#define DEBUG_LL_AM335X(p, mach)					\
+	_DEBUG_LL_ENTRY(mach, AM335X_UART##p##_BASE, OMAP_PORT_SHIFT,	\
+		AM335XUART##p)
+
 static inline void __arch_decomp_setup(unsigned long arch_id)
 {
 	int port = 0;
@@ -178,6 +182,8 @@ static inline void __arch_decomp_setup(unsigned long arch_id)
 		/* TI8148 base boards using UART1 */
 		DEBUG_LL_TI81XX(1, ti8148evm);

+		/* AM335x base boards using UART1 */
+		DEBUG_LL_AM335X(1, am335xevm);
 	} while (0);
 }

--
1.6.2.4