MIPS: Add initial support for the Atheros AR71XX/AR724X/AR931X SoCs
This patch adds initial support for various Atheros SoCs based on the
MIPS 24Kc core. The following models are supported at the moment:
- AR7130
- AR7141
- AR7161
- AR9130
- AR9132
- AR7240
- AR7241
- AR7242
The current patch contains minimal support only, but the resulting
kernel can boot into user-space with using of an initramfs image on
various boards which are using these SoCs. Support for more built-in
devices and individual boards will be implemented in further patches.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Imre Kaloz <kaloz@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: Luis R. Rodriguez <lrodriguez@atheros.com>
Cc: Cliff Holden <Cliff.Holden@Atheros.com>
Cc: Kathy Giori <Kathy.Giori@Atheros.com>
Patchwork: https://patchwork.linux-mips.org/patch/1947/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/ath79/early_printk.c b/arch/mips/ath79/early_printk.c
new file mode 100644
index 0000000..7499b0e
--- /dev/null
+++ b/arch/mips/ath79/early_printk.c
@@ -0,0 +1,36 @@
+/*
+ * Atheros AR71XX/AR724X/AR913X SoC early printk support
+ *
+ * Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ *
+ * 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.
+ */
+
+#include <linux/io.h>
+#include <linux/serial_reg.h>
+#include <asm/addrspace.h>
+
+#include <asm/mach-ath79/ar71xx_regs.h>
+
+static inline void prom_wait_thre(void __iomem *base)
+{
+ u32 lsr;
+
+ do {
+ lsr = __raw_readl(base + UART_LSR * 4);
+ if (lsr & UART_LSR_THRE)
+ break;
+ } while (1);
+}
+
+void prom_putchar(unsigned char ch)
+{
+ void __iomem *base = (void __iomem *)(KSEG1ADDR(AR71XX_UART_BASE));
+
+ prom_wait_thre(base);
+ __raw_writel(ch, base + UART_TX * 4);
+ prom_wait_thre(base);
+}