Radeon DRM GART mapping bogosity

[Dave Airlie]

> In the meantime, here's a patch against current Linus "git" that I'm
> tempted to push asap so that at least 2.6.12 avoids the problem of
> overlapping which causes random stuffs to happen with lockups. The
> "issue" here is even if you don't have an r300-friendly DRM, it will
> still try to initialize those things, even if it ultimately fails,
> provided you have a new enough X.org, and thus will screw up the
> mapping.

If Michel Daenzer thinks this is okay, he was the last person to dig
around in that area with the changes for the IGPs, I'm away from my
setup so I can't look at this for another while, but if you can get
consensus quickly send it to Linus...

Dave.

> 
> Index: linux-work/drivers/char/drm/radeon_drv.h
> ===================================================================
> --- linux-work.orig/drivers/char/drm/radeon_drv.h       2005-05-02 10:48:09.000000000 +1000
> +++ linux-work/drivers/char/drm/radeon_drv.h    2005-05-03 17:51:55.000000000 +1000
> @@ -346,6 +346,7 @@
>  #define RADEON_CLOCK_CNTL_DATA         0x000c
>  #      define RADEON_PLL_WR_EN                 (1 << 7)
>  #define RADEON_CLOCK_CNTL_INDEX                0x0008
> +#define RADEON_CONFIG_MEMSIZE          0x00f8
>  #define RADEON_CONFIG_APER_SIZE                0x0108
>  #define RADEON_CRTC_OFFSET             0x0224
>  #define RADEON_CRTC_OFFSET_CNTL                0x0228
> Index: linux-work/drivers/char/drm/radeon_cp.c
> ===================================================================
> --- linux-work.orig/drivers/char/drm/radeon_cp.c        2005-05-02 10:48:09.000000000 +1000
> +++ linux-work/drivers/char/drm/radeon_cp.c     2005-05-03 17:49:25.000000000 +1000
> @@ -1269,6 +1269,7 @@
>  {
>         drm_radeon_private_t *dev_priv = dev->dev_private;;
>         DRM_DEBUG( "\n" );
> +       u32 gart_loc;
> 
>         dev_priv->is_pci = init->is_pci;
> 
> @@ -1476,8 +1477,12 @@
> 
>         dev_priv->gart_size = init->gart_size;
> -       dev_priv->gart_vm_start = dev_priv->fb_location
> -                               + RADEON_READ( RADEON_CONFIG_APER_SIZE );
> +       gart_loc = dev_priv->fb_location + RADEON_READ( RADEON_CONFIG_MEMSIZE );
> +       /* overflow ? */
> +       if ((gart_loc + dev_priv->gart_size) < dev_priv->fb_location)
> +               gart_loc = dev_priv->fb_location - dev_priv->gart_size;
> +
> +       dev_priv->gart_vm_start = gart_loc;
> 
>  #if __OS_HAS_AGP
>         if ( !dev_priv->is_pci )
> 
>