linux/arch/arm/mach-ep93xx/include/mach/uncompress.h
Hartley Sweeten 92e88aa7fb [ARM] 5276/1: ep93xx: allow selecting UART for early kernel messages
Currently on the EP93xx platform early kernel messages go to UART1.
Since this UART is the only one that has modem control signals it
might be used for another purpose and it is undesirable for those
messages to appear. This patch allows one of the other UARTs to be
selected in the kernel configuration. It is assumed that the
bootloader has configured and initialized the UART since this was the
previous assumption.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-10-03 11:03:39 +01:00

95 lines
2.2 KiB
C

/*
* arch/arm/mach-ep93xx/include/mach/uncompress.h
*
* Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*/
#include <mach/ep93xx-regs.h>
static unsigned char __raw_readb(unsigned int ptr)
{
return *((volatile unsigned char *)ptr);
}
static unsigned int __raw_readl(unsigned int ptr)
{
return *((volatile unsigned int *)ptr);
}
static void __raw_writeb(unsigned char value, unsigned int ptr)
{
*((volatile unsigned char *)ptr) = value;
}
static void __raw_writel(unsigned int value, unsigned int ptr)
{
*((volatile unsigned int *)ptr) = value;
}
#if defined(CONFIG_EP93XX_EARLY_UART1)
#define UART_BASE EP93XX_UART1_PHYS_BASE
#elif defined(CONFIG_EP93XX_EARLY_UART2)
#define UART_BASE EP93XX_UART2_PHYS_BASE
#elif defined(CONFIG_EP93XX_EARLY_UART3)
#define UART_BASE EP93XX_UART3_PHYS_BASE
#else
#define UART_BASE EP93XX_UART1_PHYS_BASE
#endif
#define PHYS_UART_DATA (UART_BASE + 0x00)
#define PHYS_UART_FLAG (UART_BASE + 0x18)
#define UART_FLAG_TXFF 0x20
static inline void putc(int c)
{
int i;
for (i = 0; i < 1000; i++) {
/* Transmit fifo not full? */
if (!(__raw_readb(PHYS_UART_FLAG) & UART_FLAG_TXFF))
break;
}
__raw_writeb(c, PHYS_UART_DATA);
}
static inline void flush(void)
{
}
/*
* Some bootloaders don't turn off DMA from the ethernet MAC before
* jumping to linux, which means that we might end up with bits of RX
* status and packet data scribbled over the uncompressed kernel image.
* Work around this by resetting the ethernet MAC before we uncompress.
*/
#define PHYS_ETH_SELF_CTL 0x80010020
#define ETH_SELF_CTL_RESET 0x00000001
static void ethernet_reset(void)
{
unsigned int v;
/* Reset the ethernet MAC. */
v = __raw_readl(PHYS_ETH_SELF_CTL);
__raw_writel(v | ETH_SELF_CTL_RESET, PHYS_ETH_SELF_CTL);
/* Wait for reset to finish. */
while (__raw_readl(PHYS_ETH_SELF_CTL) & ETH_SELF_CTL_RESET)
;
}
static void arch_decomp_setup(void)
{
ethernet_reset();
}
#define arch_decomp_wdog()