linux/arch/arm/plat-samsung/include/plat/uncompress.h
Kukjin Kim 171c067c1a ARM: EXYNOS: add support uart for EXYNOS4 and EXYNOS5
Actually, the base address of uart is different between EXYNOS4
and EXYNOS5 and this patch enables to support uart for EXYNOS4
and EXYNOS5 SoCs at runtime.

Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-03-14 02:13:05 -07:00

187 lines
3.9 KiB
C

/* arch/arm/plat-samsung/include/plat/uncompress.h
*
* Copyright 2003, 2007 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* S3C - uncompress code
*
* 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.
*/
#ifndef __ASM_PLAT_UNCOMPRESS_H
#define __ASM_PLAT_UNCOMPRESS_H
typedef unsigned int upf_t; /* cannot include linux/serial_core.h */
/* uart setup */
unsigned int fifo_mask;
unsigned int fifo_max;
/* forward declerations */
static void arch_detect_cpu(void);
/* defines for UART registers */
#include <plat/regs-serial.h>
#include <plat/regs-watchdog.h>
/* working in physical space... */
#undef S3C2410_WDOGREG
#define S3C2410_WDOGREG(x) ((S3C24XX_PA_WATCHDOG + (x)))
/* how many bytes we allow into the FIFO at a time in FIFO mode */
#define FIFO_MAX (14)
#ifdef S3C_PA_UART
#define uart_base S3C_PA_UART + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT)
#endif
static __inline__ void
uart_wr(unsigned int reg, unsigned int val)
{
volatile unsigned int *ptr;
ptr = (volatile unsigned int *)(reg + uart_base);
*ptr = val;
}
static __inline__ unsigned int
uart_rd(unsigned int reg)
{
volatile unsigned int *ptr;
ptr = (volatile unsigned int *)(reg + uart_base);
return *ptr;
}
/* we can deal with the case the UARTs are being run
* in FIFO mode, so that we don't hold up our execution
* waiting for tx to happen...
*/
static void putc(int ch)
{
if (uart_rd(S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE) {
int level;
while (1) {
level = uart_rd(S3C2410_UFSTAT);
level &= fifo_mask;
if (level < fifo_max)
break;
}
} else {
/* not using fifos */
while ((uart_rd(S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE) != S3C2410_UTRSTAT_TXE)
barrier();
}
/* write byte to transmission register */
uart_wr(S3C2410_UTXH, ch);
}
static inline void flush(void)
{
}
#define __raw_writel(d, ad) \
do { \
*((volatile unsigned int __force *)(ad)) = (d); \
} while (0)
/* CONFIG_S3C_BOOT_WATCHDOG
*
* Simple boot-time watchdog setup, to reboot the system if there is
* any problem with the boot process
*/
#ifdef CONFIG_S3C_BOOT_WATCHDOG
#define WDOG_COUNT (0xff00)
static inline void arch_decomp_wdog(void)
{
__raw_writel(WDOG_COUNT, S3C2410_WTCNT);
}
static void arch_decomp_wdog_start(void)
{
__raw_writel(WDOG_COUNT, S3C2410_WTDAT);
__raw_writel(WDOG_COUNT, S3C2410_WTCNT);
__raw_writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128 | S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x80), S3C2410_WTCON);
}
#else
#define arch_decomp_wdog_start()
#define arch_decomp_wdog()
#endif
#ifdef CONFIG_S3C_BOOT_ERROR_RESET
static void arch_decomp_error(const char *x)
{
putstr("\n\n");
putstr(x);
putstr("\n\n -- System resetting\n");
__raw_writel(0x4000, S3C2410_WTDAT);
__raw_writel(0x4000, S3C2410_WTCNT);
__raw_writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128 | S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x40), S3C2410_WTCON);
while(1);
}
#define arch_error arch_decomp_error
#endif
#ifdef CONFIG_S3C_BOOT_UART_FORCE_FIFO
static inline void arch_enable_uart_fifo(void)
{
u32 fifocon = uart_rd(S3C2410_UFCON);
if (!(fifocon & S3C2410_UFCON_FIFOMODE)) {
fifocon |= S3C2410_UFCON_RESETBOTH;
uart_wr(S3C2410_UFCON, fifocon);
/* wait for fifo reset to complete */
while (1) {
fifocon = uart_rd(S3C2410_UFCON);
if (!(fifocon & S3C2410_UFCON_RESETBOTH))
break;
}
}
}
#else
#define arch_enable_uart_fifo() do { } while(0)
#endif
static void
arch_decomp_setup(void)
{
/* we may need to setup the uart(s) here if we are not running
* on an BAST... the BAST will have left the uarts configured
* after calling linux.
*/
arch_detect_cpu();
arch_decomp_wdog_start();
/* Enable the UART FIFOs if they where not enabled and our
* configuration says we should turn them on.
*/
arch_enable_uart_fifo();
}
#endif /* __ASM_PLAT_UNCOMPRESS_H */