This implements support for devices using AMD Geode companion chip

CS5536 that have the Boot ROM on NOR flash that is directly connected to
FLASH_CS3 (Boot Flash Chip Select).
We need to write enable it in the NORF_CTL MSR register for flashrom to
be able to write to it, including JEDEC probe commands.

This patch allows us to stop using AMD gx_utils.ko for BIOS flashing on
the DBE61.

Signed-off-by: Mart Raudsepp <mart.raudsepp@artecdesign.ee>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>



git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3097 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
This commit is contained in:
Mart Raudsepp 2008-02-08 09:59:58 +00:00 committed by Uwe Hermann
parent d2be99c62d
commit 99062ae5ad
1 changed files with 33 additions and 12 deletions

View File

@ -228,6 +228,8 @@ static int enable_flash_cs5530(struct pci_dev *dev, const char *name)
static int enable_flash_cs5536(struct pci_dev *dev, const char *name)
{
#define MSR_NORF_CTL 0x51400018
int fd_msr;
unsigned char buf[8];
unsigned int addr = 0x1808;
@ -243,34 +245,53 @@ static int enable_flash_cs5536(struct pci_dev *dev, const char *name)
* could have potential problems on SMP machines since it
* assumes cpu0, but it is safe on the Geode which is not SMP.
*
* Geode systems also write protect the NOR flash chip itself
* via MSR_NORF_CTL. To enable write to NOR Boot flash for the
* benefit of systems that have such a setup, raise
* MSR 0x51400018 WE_CS3 (write enable Boot Flash Chip Select).
*
* This is probably not portable beyond Linux.
*/
fd_msr = open("/dev/cpu/0/msr", O_RDONLY);
fd_msr = open("/dev/cpu/0/msr", O_RDWR);
if (!fd_msr) {
perror("open msr");
return -1;
}
lseek64(fd_msr, (off64_t) addr, SEEK_SET);
read(fd_msr, buf, 8);
close(fd_msr);
printf("Enabling Geode MSR to write to flash.\n");
if (buf[7] != 0x22) {
printf("Enabling Geode MSR to write to flash.\n");
buf[7] &= 0xFB;
fd_msr = open("/dev/cpu/0/msr", O_WRONLY);
if (!fd_msr) {
perror("open msr");
return -1;
}
buf[7] &= 0xfb;
lseek64(fd_msr, (off64_t) addr, SEEK_SET);
if (write(fd_msr, buf, 8) < 0) {
perror("msr write");
printf
("Cannot write to MSR. Make sure msr kernel is loaded: 'modprobe msr'\n");
printf("Cannot write to MSR. Did you run 'modprobe msr'?\n");
return -1;
}
close(fd_msr);
}
lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET);
if (read(fd_msr, buf, 8) != 8) {
perror("read msr");
return -1;
}
/* Raise WE_CS3 bit. */
buf[0] |= 0x08;
lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET);
if (write(fd_msr, buf, 8) < 0) {
perror("msr write");
printf("Cannot write to MSR. Did you run 'modprobe msr'?\n");
return -1;
}
close(fd_msr);
#undef MSR_NORF_CTL
return 0;
}