summaryrefslogtreecommitdiffstats
path: root/kernel/arch/mips/ath25/early_printk.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/arch/mips/ath25/early_printk.c')
-rw-r--r--kernel/arch/mips/ath25/early_printk.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/kernel/arch/mips/ath25/early_printk.c b/kernel/arch/mips/ath25/early_printk.c
new file mode 100644
index 000000000..36035b628
--- /dev/null
+++ b/kernel/arch/mips/ath25/early_printk.c
@@ -0,0 +1,44 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
+ */
+
+#include <linux/mm.h>
+#include <linux/io.h>
+#include <linux/serial_reg.h>
+
+#include "devices.h"
+#include "ar2315_regs.h"
+#include "ar5312_regs.h"
+
+static inline void prom_uart_wr(void __iomem *base, unsigned reg,
+ unsigned char ch)
+{
+ __raw_writel(ch, base + 4 * reg);
+}
+
+static inline unsigned char prom_uart_rr(void __iomem *base, unsigned reg)
+{
+ return __raw_readl(base + 4 * reg);
+}
+
+void prom_putchar(unsigned char ch)
+{
+ static void __iomem *base;
+
+ if (unlikely(base == NULL)) {
+ if (is_ar2315())
+ base = (void __iomem *)(KSEG1ADDR(AR2315_UART0_BASE));
+ else
+ base = (void __iomem *)(KSEG1ADDR(AR5312_UART0_BASE));
+ }
+
+ while ((prom_uart_rr(base, UART_LSR) & UART_LSR_THRE) == 0)
+ ;
+ prom_uart_wr(base, UART_TX, ch);
+ while ((prom_uart_rr(base, UART_LSR) & UART_LSR_THRE) == 0)
+ ;
+}