drm/vmwgfx: switch from ioremap_cache to memremap

Per commit 2e586a7e017a "drm/vmwgfx: Map the fifo as cached" the driver
expects the fifo registers to be cacheable.  In preparation for
deprecating ioremap_cache() convert its usage in vmwgfx to memremap().

Cc: David Airlie <airlied@linux.ie>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Sinclair Yeh <syeh@vmware.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index b7525f7..bee0a45 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -752,8 +752,14 @@
 	ttm_lock_set_kill(&dev_priv->fbdev_master.lock, false, SIGTERM);
 	dev_priv->active_master = &dev_priv->fbdev_master;
 
-	dev_priv->mmio_virt = ioremap_cache(dev_priv->mmio_start,
-					    dev_priv->mmio_size);
+	/*
+	 * Force __iomem for this mapping until the implied compiler
+	 * barriers and {READ|WRITE}_ONCE semantics from the
+	 * io{read|write}32() accessors can be replaced with explicit
+	 * barriers.
+	 */
+	dev_priv->mmio_virt = (void __iomem *) memremap(dev_priv->mmio_start,
+					    dev_priv->mmio_size, MEMREMAP_WB);
 
 	if (unlikely(dev_priv->mmio_virt == NULL)) {
 		ret = -ENOMEM;
@@ -907,7 +913,7 @@
 out_no_device:
 	ttm_object_device_release(&dev_priv->tdev);
 out_err4:
-	iounmap(dev_priv->mmio_virt);
+	memunmap((void __force *) dev_priv->mmio_virt);
 out_err3:
 	vmw_ttm_global_release(dev_priv);
 out_err0:
@@ -958,7 +964,7 @@
 		pci_release_regions(dev->pdev);
 
 	ttm_object_device_release(&dev_priv->tdev);
-	iounmap(dev_priv->mmio_virt);
+	memunmap((void __force *) dev_priv->mmio_virt);
 	if (dev_priv->ctx.staged_bindings)
 		vmw_binding_state_free(dev_priv->ctx.staged_bindings);
 	vmw_ttm_global_release(dev_priv);