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>

1 files changed, 45 insertions, 0 deletions

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