drm: radeon: Use surface for PCI GART table.

This allocates a physical surface for the PCI GART table, this way no
matter what other surface configurations exist the GART table will
always be seen by the hardware properly.

We encode the file pointer of the virtual surface allocate using a
special cookie value, called PCIGART_FILE_PRIV.  On the last close, we
release that surface.

Just to be doubly safe, we run the pcigart table setup with the main
surface control register clear.

Based upon ideas from David Airlie and Ben Benjamin Herrenschmidt.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 57 insertions, 1 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_cp.c b/drivers/gpu/drm/radeon/radeon_cp.c
index 4a56e7d626a6..a18b3688a7f0 100644
--- a/drivers/gpu/drm/radeon/radeon_cp.c
+++ b/drivers/gpu/drm/radeon/radeon_cp.c
@@ -919,6 +919,46 @@ static void radeon_set_pcigart(drm_radeon_private_t * dev_priv, int on)
         }
 }
 
+static int radeon_setup_pcigart_surface(drm_radeon_private_t *dev_priv)
+{
+        struct drm_ati_pcigart_info *gart_info = &dev_priv->gart_info;
+        struct radeon_virt_surface *vp;
+        int i;
+
+        for (i = 0; i < RADEON_MAX_SURFACES * 2; i++) {
+                if (!dev_priv->virt_surfaces[i].file_priv ||
+                    dev_priv->virt_surfaces[i].file_priv == PCIGART_FILE_PRIV)
+                        break;
+        }
+        if (i >= 2 * RADEON_MAX_SURFACES)
+                return -ENOMEM;
+        vp = &dev_priv->virt_surfaces[i];
+
+        for (i = 0; i < RADEON_MAX_SURFACES; i++) {
+                struct radeon_surface *sp = &dev_priv->surfaces[i];
+                if (sp->refcount)
+                        continue;
+
+                vp->surface_index = i;
+                vp->lower = gart_info->bus_addr;
+                vp->upper = vp->lower + gart_info->table_size;
+                vp->flags = 0;
+                vp->file_priv = PCIGART_FILE_PRIV;
+
+                sp->refcount = 1;
+                sp->lower = vp->lower;
+                sp->upper = vp->upper;
+                sp->flags = 0;
+
+                RADEON_WRITE(RADEON_SURFACE0_INFO + 16 * i, sp->flags);
+                RADEON_WRITE(RADEON_SURFACE0_LOWER_BOUND + 16 * i, sp->lower);
+                RADEON_WRITE(RADEON_SURFACE0_UPPER_BOUND + 16 * i, sp->upper);
+                return 0;
+        }
+
+        return -ENOMEM;
+}
+
 static int radeon_do_init_cp(struct drm_device *dev, drm_radeon_init_t *init,
                              struct drm_file *file_priv)
 {
@@ -1212,6 +1252,9 @@ static int radeon_do_init_cp(struct drm_device *dev, drm_radeon_init_t *init,
         } else
 #endif
         {
+                u32 sctrl;
+                int ret;
+
                 dev_priv->gart_info.table_mask = DMA_BIT_MASK(32);
                 /* if we have an offset set from userspace */
                 if (dev_priv->pcigart_offset_set) {
@@ -1253,12 +1296,25 @@ static int radeon_do_init_cp(struct drm_device *dev, drm_radeon_init_t *init,
                         }
                 }
 
-                if (!drm_ati_pcigart_init(dev, &dev_priv->gart_info)) {
+                sctrl = RADEON_READ(RADEON_SURFACE_CNTL);
+                RADEON_WRITE(RADEON_SURFACE_CNTL, 0);
+                ret = drm_ati_pcigart_init(dev, &dev_priv->gart_info);
+                RADEON_WRITE(RADEON_SURFACE_CNTL, sctrl);
+
+                if (!ret) {
                         DRM_ERROR("failed to init PCI GART!\n");
                         radeon_do_cleanup_cp(dev);
                         return -ENOMEM;
                 }
 
+                ret = radeon_setup_pcigart_surface(dev_priv);
+                if (ret) {
+                        DRM_ERROR("failed to setup GART surface!\n");
+                        drm_ati_pcigart_cleanup(dev, &dev_priv->gart_info);
+                        radeon_do_cleanup_cp(dev);
+                        return ret;
+                }
+
                 /* Turn on PCI GART */
                 radeon_set_pcigart(dev_priv, 1);
         }