Early UART configuration for 85xx on 2.6 Kernel

[mike zheng]

Hi All,

In order to debug the 8548 CDS BSP of kernel 2.6, I want setup serial port
with UART on mpc85xx as early as possible. . I add the register access
code at the beginning of  platform_init(). However the system just hanging
there with this line. If I comment out this
line"WRITE8_ADDR(M85xx_EIIADDR,0)", then linux kernel runs well.

Thanks in advance,

Mike Z

Here is the code of my mpc85xx_cds_common.c:

#define WRITE8_ADDR(address, value) \
    ((*((volatile u8 *)(address))) = (u8)(value))

#define M85xx_EII_ADDR 0xe0004500

void __init
platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
                   unsigned long r6, unsigned long r7)
{
       /* parse_bootinfo must always be called first */
       parse_bootinfo(find_bootinfo());

      /* Now we try to access register of UART */
      WRITE8_ADDR(M85xx_EII_ADDR, 0);
....
}
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