[U-Boot-Users] AMD Mirror Bit Write Buffer Programing algorythm troubles
Conn Clark
clark at esteem.com
Fri Jan 30 19:17:08 CET 2004
Hello all,
I'm having troubles with an AMD Mirror Bit Write Buffer Programing
algorythm I have written for U-Boot. I'm hoping that someone can provide
some insight to the problem. We are using an Am29LV320MB part and
according to the data sheet I am doing everything correctly (at least I
think I am ). So if someone could confirm my code is valid or wrong I
would appreciate it.
I am having troubles with the flash part decraring it has timed out. It
does complete the first buffer programing sequence and all programed
data is valid. If I force it to continue only the first buffer write to
each sector is programed.
My problems may be due to a bad chip. This is a prototype and we had
some issues with the power supply that may have dammaged the chip. I
doubt this because our Jtag debugger programs this part in write buffer
mode just fine.
Below is the two functions of intrest and I have attached the full
flash.c file.
/************* Begin code *****************/
#ifdef WRITE_BUFFER_PROG
int write_buffer_program(flash_info_t *info, ulong dest, char *src);
#endif
/*-----------------------------------------------------------------------
* Copy memory to flash, returns:
* 0 - OK
* 1 - write timeout
* 2 - Flash not erased
*/
int write_buff (flash_info_t *info, uchar *src, ulong addr, ulong cnt)
{
ulong cp, wp, data;
int i, l, rc;
wp = (addr & ~3); /* get lower word aligned address */
/*
* handle unaligned start bytes
*/
if ((l = addr - wp) != 0) {
data = 0;
for (i=0, cp=wp; i<l; ++i, ++cp) {
data = (data << 8) | (*(uchar *)cp);
}
for (; i<4 && cnt>0; ++i) {
data = (data << 8) | *src++;
--cnt;
++cp;
}
for (; cnt==0 && i<4; ++i, ++cp) {
data = (data << 8) | (*(uchar *)cp);
}
if ((rc = write_word(info, wp, data)) != 0) {
return (rc);
}
wp += 4;
}
/*
* handle word aligned part
*/
while (cnt >= 4) {
#ifdef WRITE_BUFFER_PROG
if((cnt>=32)& !(wp & 0x1F)) { /* if destination is aligned on 32
byte boundry use write burst */
if ((rc = write_buffer_program(info,wp,src)) != 0) {
return (rc);
}
wp += 32;
src += 32;
cnt -= 32;
} else
#endif
{
data = 0;
for (i=0; i<4; ++i) {
data = (data << 8) | *src++;
}
if ((rc = write_word(info, wp, data)) != 0) {
return (rc);
}
wp += 4;
cnt -= 4;
}
}
if (cnt == 0) {
return (0);
}
/*
* handle unaligned tail bytes
*/
data = 0;
for (i=0, cp=wp; i<4 && cnt>0; ++i, ++cp) {
data = (data << 8) | *src++;
--cnt;
}
for (; i<4; ++i, ++cp) {
data = (data << 8) | (*(uchar *)cp);
}
return (write_word(info, wp, data));
}
#ifdef WRITE_BUFFER_PROG
/*-----------------------------------------------------------------------
* Write a bunch of word to Flash, returns:
* 0 - OK
* 1 - write timeout
* 2 - Flash not erased
* 3 - write buffer abort
*/
int write_buffer_program(flash_info_t *info, ulong dest, char *src)
{
volatile CFG_FLASH_WORD_SIZE *target_sector;
volatile CFG_FLASH_WORD_SIZE *addr2 = (CFG_FLASH_WORD_SIZE
*)(info->start[0]);
volatile CFG_FLASH_WORD_SIZE *dest2 = (CFG_FLASH_WORD_SIZE *)dest;
volatile CFG_FLASH_WORD_SIZE *data2 = (CFG_FLASH_WORD_SIZE *)src;
CFG_FLASH_WORD_SIZE progstat;
ulong start;
int flag;
int i,j;
j=info->sector_count -1;
/*find sector start address to program*/
while(info->start[j] > dest) j--;
target_sector = (CFG_FLASH_WORD_SIZE *)(info->start[j]);
/* Check if Flash is (sufficiently) erased */
/* if ((*dest2 & *data2) != *data2) {
return (2);
} */
/* Disable interrupts which might cause a timeout here */
flag = disable_interrupts();
addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
addr2[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
target_sector[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00250025; /*
write to buffer command */
/*write count of words to buffer minus 1 */
target_sector[CFG_FLASH_ADDR0] = (32/sizeof(CFG_FLASH_WORD_SIZE)) - 1 ;
/*write first word */
/* dest2[0] = data2[0]; */
/* write the rest */
i=0;
do
{
dest2[i] = data2[i];
i++;
}while(i<(32/sizeof(CFG_FLASH_WORD_SIZE)));
/*write buffer command */
target_sector[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00290029;
/* re-enable interrupts if necessary */
if (flag)
enable_interrupts();
/* data polling for D7 */
i--; /* decrement index to point to last word written */
start = get_timer (0);
while( ((progstat=dest2[i]) & (CFG_FLASH_WORD_SIZE)0x00800080) !=
/*check for chip time out or abort*/
(data2[i] & (CFG_FLASH_WORD_SIZE)0x00800080) ){
if(progstat & (CFG_FLASH_WORD_SIZE)0x00220022) {
if(progstat & (CFG_FLASH_WORD_SIZE)0x00200020){ /*check for chip
time out*/
/* return success if it really did work */
if( (dest2[i] & (CFG_FLASH_WORD_SIZE)0x00800080) ==
(data2[i] & (CFG_FLASH_WORD_SIZE)0x00800080) ) return 0;
data2[i] = (CFG_FLASH_WORD_SIZE)0x00F000F0; /*
reset flash chip */
printf("TimeOut\n"); /* for debugging only, remove */
return 1;
}
/* return success if it really did work */
if( (dest2[i] & (CFG_FLASH_WORD_SIZE)0x00800080) ==
(data2[i] & (CFG_FLASH_WORD_SIZE)0x00800080) ) return 0;
/* if your here it is an abort condition */
addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
addr2[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00F000F0; /* Write
buffer abort reset */
printf("abort\n"); /* for debugging only, remove */
return 3;
}
if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
return (1); /* U-Boot timer time out */
}
}
return (0);
}
#endif /* WRITE_BUFFER_PROG */
/*********** End code *********/
Thanks
Conn Clark
--
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Conn Clark
Engineering Stooge clark at esteem.com
Electronic Systems Technology Inc. www.esteem.com
Stock Ticker Symbol ELST
"clark at esteem.com" Copyright 2000 By Electronic Systems Technology
This email address may be used to communicate to Conn Clark
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