drm: rework radeon memory map (radeon 1.23)
This code reworks the radeon memory map so it works better
for newer r300 chips and for a lot of older PCI chips.
It really requires a new X driver in order to take advantage of this code.
From: Ben Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/radeon_state.c b/drivers/char/drm/radeon_state.c
index 7bc2751..56e56b8 100644
--- a/drivers/char/drm/radeon_state.c
+++ b/drivers/char/drm/radeon_state.c
@@ -45,22 +45,53 @@
u32 off = *offset;
struct drm_radeon_driver_file_fields *radeon_priv;
- if (off >= dev_priv->fb_location &&
- off < (dev_priv->gart_vm_start + dev_priv->gart_size))
+ /* Hrm ... the story of the offset ... So this function converts
+ * the various ideas of what userland clients might have for an
+ * offset in the card address space into an offset into the card
+ * address space :) So with a sane client, it should just keep
+ * the value intact and just do some boundary checking. However,
+ * not all clients are sane. Some older clients pass us 0 based
+ * offsets relative to the start of the framebuffer and some may
+ * assume the AGP aperture it appended to the framebuffer, so we
+ * try to detect those cases and fix them up.
+ *
+ * Note: It might be a good idea here to make sure the offset lands
+ * in some "allowed" area to protect things like the PCIE GART...
+ */
+
+ /* First, the best case, the offset already lands in either the
+ * framebuffer or the GART mapped space
+ */
+ if ((off >= dev_priv->fb_location &&
+ off < (dev_priv->fb_location + dev_priv->fb_size)) ||
+ (off >= dev_priv->gart_vm_start &&
+ off < (dev_priv->gart_vm_start + dev_priv->gart_size)))
return 0;
- radeon_priv = filp_priv->driver_priv;
- off += radeon_priv->radeon_fb_delta;
+ /* Ok, that didn't happen... now check if we have a zero based
+ * offset that fits in the framebuffer + gart space, apply the
+ * magic offset we get from SETPARAM or calculated from fb_location
+ */
+ if (off < (dev_priv->fb_size + dev_priv->gart_size)) {
+ radeon_priv = filp_priv->driver_priv;
+ off += radeon_priv->radeon_fb_delta;
+ }
- DRM_DEBUG("offset fixed up to 0x%x\n", off);
+ /* Finally, assume we aimed at a GART offset if beyond the fb */
+ if (off > (dev_priv->fb_location + dev_priv->fb_size))
+ off = off - (dev_priv->fb_location + dev_priv->fb_size) +
+ dev_priv->gart_vm_start;
- if (off < dev_priv->fb_location ||
- off >= (dev_priv->gart_vm_start + dev_priv->gart_size))
- return DRM_ERR(EINVAL);
-
- *offset = off;
-
- return 0;
+ /* Now recheck and fail if out of bounds */
+ if ((off >= dev_priv->fb_location &&
+ off < (dev_priv->fb_location + dev_priv->fb_size)) ||
+ (off >= dev_priv->gart_vm_start &&
+ off < (dev_priv->gart_vm_start + dev_priv->gart_size))) {
+ DRM_DEBUG("offset fixed up to 0x%x\n", off);
+ *offset = off;
+ return 0;
+ }
+ return DRM_ERR(EINVAL);
}
static __inline__ int radeon_check_and_fixup_packets(drm_radeon_private_t *
@@ -3012,6 +3043,9 @@
case RADEON_SETPARAM_PCIGART_LOCATION:
dev_priv->pcigart_offset = sp.value;
break;
+ case RADEON_SETPARAM_NEW_MEMMAP:
+ dev_priv->new_memmap = sp.value;
+ break;
default:
DRM_DEBUG("Invalid parameter %d\n", sp.param);
return DRM_ERR(EINVAL);