summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2013-10-08 16:44:17 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2013-10-29 11:06:04 +0000
commit494e492dd88d36cd201eae99873492450d1e9b4f (patch)
tree1137d16a179ef29ac5c001e97c2ce1b5f48fec4b
parent3159f372354e8e1f5dee714663d705dd2c7e0759 (diff)
downloadlinux-494e492dd88d36cd201eae99873492450d1e9b4f.tar.bz2
ARM: 7850/1: DEBUG_LL on efm32 SoCs
This implements output of debug messages on efm32 SoCs. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
-rw-r--r--arch/arm/Kconfig.debug17
-rw-r--r--arch/arm/include/debug/efm32.S45
2 files changed, 62 insertions, 0 deletions
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 9762c84b4198..2b3206824353 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -834,6 +834,20 @@ choice
options; the platform specific options are deprecated
and will be soon removed.
+ config DEBUG_LL_UART_EFM32
+ bool "Kernel low-level debugging via efm32 UART"
+ depends on ARCH_EFM32
+ help
+ Say Y here if you want the debug print routines to direct
+ their output to an UART or USART port on efm32 based
+ machines. Use the following addresses for DEBUG_UART_PHYS:
+
+ 0x4000c000 | USART0
+ 0x4000c400 | USART1
+ 0x4000c800 | USART2
+ 0x4000e000 | UART0
+ 0x4000e400 | UART1
+
config DEBUG_LL_UART_PL01X
bool "Kernel low-level debugging via ARM Ltd PL01x Primecell UART"
help
@@ -885,6 +899,7 @@ config DEBUG_LL_INCLUDE
default "debug/8250.S" if DEBUG_LL_UART_8250 || DEBUG_UART_8250
default "debug/pl01x.S" if DEBUG_LL_UART_PL01X || DEBUG_UART_PL01X
default "debug/exynos.S" if DEBUG_EXYNOS_UART
+ default "debug/efm32.S" if DEBUG_LL_UART_EFM32
default "debug/icedcc.S" if DEBUG_ICEDCC
default "debug/imx.S" if DEBUG_IMX1_UART || \
DEBUG_IMX25_UART || \
@@ -951,6 +966,7 @@ config DEBUG_UART_PHYS
default 0x20064000 if DEBUG_RK29_UART1 || DEBUG_RK3X_UART2
default 0x20068000 if DEBUG_RK29_UART2 || DEBUG_RK3X_UART3
default 0x20201000 if DEBUG_BCM2835
+ default 0x4000e400 if DEBUG_LL_UART_EFM32
default 0x40090000 if ARCH_LPC32XX
default 0x40100000 if DEBUG_PXA_UART1
default 0x42000000 if ARCH_GEMINI
@@ -981,6 +997,7 @@ config DEBUG_UART_PHYS
default 0xfff36000 if DEBUG_HIGHBANK_UART
default 0xfffff700 if ARCH_IOP33X
depends on DEBUG_LL_UART_8250 || DEBUG_LL_UART_PL01X || \
+ DEBUG_LL_UART_EFM32 || \
DEBUG_UART_8250 || DEBUG_UART_PL01X
config DEBUG_UART_VIRT
diff --git a/arch/arm/include/debug/efm32.S b/arch/arm/include/debug/efm32.S
new file mode 100644
index 000000000000..2265a199280c
--- /dev/null
+++ b/arch/arm/include/debug/efm32.S
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2013 Pengutronix
+ * Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define UARTn_CMD 0x000c
+#define UARTn_CMD_TXEN 0x0004
+
+#define UARTn_STATUS 0x0010
+#define UARTn_STATUS_TXC 0x0020
+#define UARTn_STATUS_TXBL 0x0040
+
+#define UARTn_TXDATA 0x0034
+
+ .macro addruart, rx, tmp
+ ldr \rx, =(CONFIG_DEBUG_UART_PHYS)
+
+ /*
+ * enable TX. The driver might disable it to save energy. We
+ * don't care about disabling at the end as during debug power
+ * consumption isn't that important.
+ */
+ ldr \tmp, =(UARTn_CMD_TXEN)
+ str \tmp, [\rx, #UARTn_CMD]
+ .endm
+
+ .macro senduart,rd,rx
+ strb \rd, [\rx, #UARTn_TXDATA]
+ .endm
+
+ .macro waituart,rd,rx
+1001: ldr \rd, [\rx, #UARTn_STATUS]
+ tst \rd, #UARTn_STATUS_TXBL
+ beq 1001b
+ .endm
+
+ .macro busyuart,rd,rx
+1001: ldr \rd, [\rx, UARTn_STATUS]
+ tst \rd, #UARTn_STATUS_TXC
+ bne 1001b
+ .endm