[PATCH] ARM: debug: add support for alternate 8250 register layout

From: Mans Rullgard
Date: Fri Oct 02 2015 - 08:12:37 EST


Some SoCs have a UART with a non-standard register layout. This
allows the debug console to work with these.

Signed-off-by: Mans Rullgard <mans@xxxxxxxxx>
---
I would have preferred a more accurate description of the UART, but I've
not managed to figure out who the vendor is.
---
arch/arm/Kconfig.debug | 4 ++++
arch/arm/include/debug/8250.S | 12 ++++++++++++
2 files changed, 16 insertions(+)

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 0cfd7f9..8d5c837 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -1597,6 +1597,10 @@ config DEBUG_UART_8250_WORD
DEBUG_BCM_KONA_UART || DEBUG_RK32_UART2 || \
DEBUG_BRCMSTB_UART

+config DEBUG_UART_8250_AU
+ bool "8250 UART has Alchemy register layout"
+ depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
+
config DEBUG_UART_8250_FLOW_CONTROL
bool "Enable flow control for 8250 UART"
depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
diff --git a/arch/arm/include/debug/8250.S b/arch/arm/include/debug/8250.S
index 7f7446f..3c9ef68 100644
--- a/arch/arm/include/debug/8250.S
+++ b/arch/arm/include/debug/8250.S
@@ -9,6 +9,18 @@
*/
#include <linux/serial_reg.h>

+#ifdef CONFIG_DEBUG_UART_8250_AU
+
+#undef UART_TX
+#undef UART_LSR
+#undef UART_MSR
+
+#define UART_TX 1
+#define UART_LSR 7
+#define UART_MSR 8
+
+#endif
+
.macro addruart, rp, rv, tmp
ldr \rp, =CONFIG_DEBUG_UART_PHYS
ldr \rv, =CONFIG_DEBUG_UART_VIRT
--
2.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/