drm/vmwgfx: Map the fifo as cached

On the guest kernel side, previously the FIFO has been mapped write-
combined. This has worked since VMs up to now has not honored the mapping
type and mapped the FIFO cached anyway. Since the FIFO is accessed cached
by the CPU on the virtual device side, this leads to inconsistent
mappings once the guest starts to honor the mapping types.

So ask for cached mappings when we map the FIFO. We do this by
using ioremap_cache() instead of ioremap_wc(), and remove the MTRR setup.
On the TTM side, MOBs, GMRs and VRAM buffers are already requesting
cached mappings for kernel- and user-space.

Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index e13b20bd9908d65b4b906d11f2a9d3aae0d8e847..2c7a25c71af2979c784b6cb4a87ee2088d4f8fbb 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -752,12 +752,8 @@ static int vmw_driver_load(struct drm_device *dev, unsigned long chipset)
        ttm_lock_set_kill(&dev_priv->fbdev_master.lock, false, SIGTERM);
        dev_priv->active_master = &dev_priv->fbdev_master;
 
-
-       dev_priv->mmio_mtrr = arch_phys_wc_add(dev_priv->mmio_start,
-                                              dev_priv->mmio_size);
-
-       dev_priv->mmio_virt = ioremap_wc(dev_priv->mmio_start,
-                                        dev_priv->mmio_size);
+       dev_priv->mmio_virt = ioremap_cache(dev_priv->mmio_start,
+                                           dev_priv->mmio_size);
 
        if (unlikely(dev_priv->mmio_virt == NULL)) {
                ret = -ENOMEM;
@@ -913,7 +909,6 @@ out_no_device:
 out_err4:
        iounmap(dev_priv->mmio_virt);
 out_err3:
-       arch_phys_wc_del(dev_priv->mmio_mtrr);
        vmw_ttm_global_release(dev_priv);
 out_err0:
        for (i = vmw_res_context; i < vmw_res_max; ++i)
@@ -964,7 +959,6 @@ static int vmw_driver_unload(struct drm_device *dev)
 
        ttm_object_device_release(&dev_priv->tdev);
        iounmap(dev_priv->mmio_virt);
-       arch_phys_wc_del(dev_priv->mmio_mtrr);
        if (dev_priv->ctx.staged_bindings)
                vmw_binding_state_free(dev_priv->ctx.staged_bindings);
        vmw_ttm_global_release(dev_priv);

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index b60b41f95e74477b1b2928f39479abaf4c3e7175..a20f482848eebdaa422be61f938525e1302e0f9e 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -376,7 +376,6 @@ struct vmw_private {
        uint32_t initial_width;
        uint32_t initial_height;
        u32 __iomem *mmio_virt;
-       int mmio_mtrr;
        uint32_t capabilities;
        uint32_t max_gmr_ids;
        uint32_t max_gmr_pages;