2013.01.23. 13:05 keltezéssel, John Crispin írta:
> Add the code needed to make early printk work.
>
> Signed-off-by: John Crispin <blogic@xxxxxxxxxxx>
> ---
> arch/mips/ralink/early_printk.c | 43 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 43 insertions(+)
> create mode 100644 arch/mips/ralink/early_printk.c
>
> diff --git a/arch/mips/ralink/early_printk.c b/arch/mips/ralink/early_printk.c
> new file mode 100644
> index 0000000..c610084
> --- /dev/null
> +++ b/arch/mips/ralink/early_printk.c
> @@ -0,0 +1,43 @@
> +/*
> + * 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.
> + *
> + * Copyright (C) 2011-2012 Gabor Juhos <juhosg@xxxxxxxxxxx>
> + */
> +
> +#include <linux/io.h>
> +#include <linux/serial_reg.h>
> +
> +#include <asm/addrspace.h>
> +
> +/* UART registers */
> +#define EARLY_UART_BASE 0x10000c00
> +
> +#define UART_REG_RX 0
> +#define UART_REG_TX 1
> +#define UART_REG_IER 2
> +#define UART_REG_IIR 3
> +#define UART_REG_FCR 4
> +#define UART_REG_LCR 5
> +#define UART_REG_MCR 6
> +#define UART_REG_LSR 7
> +
> +static inline void uart_w32(u32 val, unsigned reg)
> +{
> + __raw_writel((val),
> + (void __iomem *)(KSEG1ADDR(EARLY_UART_BASE) + 4 * (reg)));
Introducing a variable for the base address would make the code much more
readable. Additionaly, compared to the OpenWrt code this is not a macro anymore,
so the parentheses around 'val' and 'reg' are not needed.
> +}
> +
> +static inline u32 uart_r32(unsigned reg)
> +{
> + return __raw_readl(
> + (void __iomem *)(KSEG1ADDR(EARLY_UART_BASE) + 4 * (reg)));
Ditto.
> +}
> +
> +void prom_putchar(unsigned char ch)
> +{
> + while (((uart_r32(UART_REG_LSR)) & UART_LSR_THRE) == 0);
> + uart_w32(UART_REG_TX, ch);
> + while (((uart_r32(UART_REG_LSR)) & UART_LSR_THRE) == 0);
There are some superfluous parentheses inside the conditions of the while
statements. Apart from that, the trailing semicolons will cause checkpatch errors.
-Gabor
-Gabor
