--- /dev/null +++ b/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) + ; +} --- a/arch/mips/ath25/Makefile +++ b/arch/mips/ath25/Makefile @@ -9,5 +9,8 @@ # obj-y += board.o prom.o devices.o + +obj-$(CONFIG_EARLY_PRINTK) += early_printk.o + obj-$(CONFIG_SOC_AR5312) += ar5312.o obj-$(CONFIG_SOC_AR2315) += ar2315.o --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -106,6 +106,7 @@ config ATH25 select SYS_HAS_CPU_MIPS32_R1 select SYS_SUPPORTS_BIG_ENDIAN select SYS_SUPPORTS_32BIT_KERNEL + select SYS_HAS_EARLY_PRINTK help Support for Atheros AR231x and Atheros AR531x based boards