[LinuxBIOS] r2967 - trunk/util/flashrom

[Jordan Crouse]

On 13/11/07 17:45 +0100, svn at openbios.org wrote:
> Author: jcrouse
> Date: 2007-11-13 17:45:22 +0100 (Tue, 13 Nov 2007)
> New Revision: 2967
> 
> Modified:
>    trunk/util/flashrom/chipset_enable.c
> Log:
> [LinuxBIOS] flashrom support for AMD Geode CS5536
> 
> Attached is a patch that enables AMD Geode CS5536 chipset support.  I
> have tested it successfully on a MSM800 board from digital logic.
> 
> Signed-off-by: Lane Brooks <lbrooks at mit.edu>
> Acked-by: Jordan Crouse <jordan.crouse at amd.com>

Sorry this took so long - this is essentially Lane's patch from
http://www.linuxbios.org/pipermail/linuxbios/2007-October/025316.html
but I went ahead and changed the lseeks to lseek64 just to be more correct.

Thanks,
Jordan

> 
> 
> Modified: trunk/util/flashrom/chipset_enable.c
> ===================================================================
> --- trunk/util/flashrom/chipset_enable.c	2007-11-13 16:24:15 UTC (rev 2966)
> +++ trunk/util/flashrom/chipset_enable.c	2007-11-13 16:45:22 UTC (rev 2967)
> @@ -23,9 +23,15 @@
>   * Contains the chipset specific flash enables.
>   */
>  
> +#define _LARGEFILE64_SOURCE
> +
>  #include <stdio.h>
>  #include <pci/pci.h>
>  #include <stdlib.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <unistd.h>
>  #include "flash.h"
>  
>  static int enable_flash_ali_m1533(struct pci_dev *dev, char *name)
> @@ -218,6 +224,54 @@
>  	return 0;
>  }
>  
> +static int enable_flash_cs5536(struct pci_dev *dev, char *name)
> +{
> +	int fd_msr;
> +	unsigned char buf[8];
> +	unsigned int addr = 0x1808;
> +
> +	/* Geode systems write protect the BIOS via RCONFs (cache
> +	 * settings similar to MTRRs). To unlock, change MSR 0x1808
> +	 * top byte to 0x22. Reading and writing to msr, however
> +	 * requires instrucitons rdmsr/wrmsr, which are ring0 privileged
> +	 * instructions so only the kernel can do the read/write.  This
> +	 * function, therefore, requires that the msr kernel module be
> +	 * loaded to access these instructions from user space using
> +	 * device /dev/cpu/0/msr.  This hard-coded driver location
> +	 * could have potential problems on SMP machines since it
> +	 * assumes cpu0, but it is safe on the geode which is not SMP.
> +	 *
> +	 * This is probably not portable beyond linux.
> +	 */
> +
> +	fd_msr = open("/dev/cpu/0/msr", O_RDONLY);
> +	if (!fd_msr) {
> +		perror("open msr");
> +		return -1;
> +	}
> +	lseek64(fd_msr, (off64_t) addr, SEEK_SET);
> +	read(fd_msr, buf, 8);
> +	close(fd_msr);
> +	if (buf[7] != 0x22) {
> +		printf("Enabling Geode MSR to write to flash.\n");
> +		buf[7] = 0x22;
> +		fd_msr = open("/dev/cpu/0/msr", O_WRONLY);
> +		if (!fd_msr) {
> +			perror("open msr");
> +			return -1;
> +		}
> +		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");
> +			return -1;
> +		}
> +		close(fd_msr);
> +	}
> +	return 0;
> +}
> +
>  static int enable_flash_sc1100(struct pci_dev *dev, char *name)
>  {
>  	uint8_t new;
> @@ -460,6 +514,7 @@
>  	{0x1078, 0x0100, "CS5530/CS5530A", enable_flash_cs5530},
>  	{0x100b, 0x0510, "SC1100", enable_flash_sc1100},
>  	{0x1039, 0x0008, "SIS5595", enable_flash_sis5595},
> +	{0x1022, 0x2080, "AMD GEODE CS5536", enable_flash_cs5536},
>  	{0x1022, 0x7468, "AMD8111", enable_flash_amd8111},
>  	{0x10B9, 0x1533, "ALi M1533", enable_flash_ali_m1533},
>  	/* this fallthrough looks broken. */
> 
> 
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> 
> 

-- 
Jordan Crouse
Systems Software Development Engineer 
Advanced Micro Devices, Inc.