drm/i915: fixup __iomem mixups in ringbuffer.c

Two things:
- ring->virtual start is an __iomem pointer, treat it accordingly.
- dev_priv->status_page.page_addr is now always a cpu addr, no pointer
  casting needed for that.

Take the opportunity to remove the unnecessary drm indirection when
setting up the ringbuffer iomapping.

v2: Add a compiler barrier before reading the hw status page.

Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 17 insertions, 31 deletions

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index f0c0a7ed90e5..b5a1a72d3325 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -256,7 +256,7 @@ static int i915_dma_resume(struct drm_device * dev)
 
         DRM_DEBUG_DRIVER("%s\n", __func__);
 
-        if (ring->map.handle == NULL) {
+        if (ring->virtual_start == NULL) {
                 DRM_ERROR("can not ioremap virtual address for"
                           " ring buffer\n");
                 return -ENOMEM;
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index df3a770d60fa..38096080a3de 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -977,20 +977,14 @@ static int intel_init_ring_buffer(struct drm_device *dev,
         if (ret)
                 goto err_unref;
 
-        ring->map.size = ring->size;
-        ring->map.offset = dev->agp->base + obj->gtt_offset;
-        ring->map.type = 0;
-        ring->map.flags = 0;
-        ring->map.mtrr = 0;
-
-        drm_core_ioremap_wc(&ring->map, dev);
-        if (ring->map.handle == NULL) {
+        ring->virtual_start = ioremap_wc(dev->agp->base + obj->gtt_offset,
+                                         ring->size);
+        if (ring->virtual_start == NULL) {
                 DRM_ERROR("Failed to map ringbuffer.\n");
                 ret = -EINVAL;
                 goto err_unpin;
         }
 
-        ring->virtual_start = ring->map.handle;
         ret = ring->init(ring);
         if (ret)
                 goto err_unmap;
@@ -1006,7 +1000,7 @@ static int intel_init_ring_buffer(struct drm_device *dev,
         return 0;
 
 err_unmap:
-        drm_core_ioremapfree(&ring->map, dev);
+        iounmap(ring->virtual_start);
 err_unpin:
         i915_gem_object_unpin(obj);
 err_unref:
@@ -1034,7 +1028,7 @@ void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring)
 
         I915_WRITE_CTL(ring, 0);
 
-        drm_core_ioremapfree(&ring->map, ring->dev);
+        iounmap(ring->virtual_start);
 
         i915_gem_object_unpin(ring->obj);
         drm_gem_object_unreference(&ring->obj->base);
@@ -1048,7 +1042,7 @@ void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring)
 
 static int intel_wrap_ring_buffer(struct intel_ring_buffer *ring)
 {
-        unsigned int *virt;
+        uint32_t __iomem *virt;
         int rem = ring->size - ring->tail;
 
         if (ring->space < rem) {
@@ -1057,12 +1051,10 @@ static int intel_wrap_ring_buffer(struct intel_ring_buffer *ring)
                         return ret;
         }
 
-        virt = (unsigned int *)(ring->virtual_start + ring->tail);
-        rem /= 8;
-        while (rem--) {
-                *virt++ = MI_NOOP;
-                *virt++ = MI_NOOP;
-        }
+        virt = ring->virtual_start + ring->tail;
+        rem /= 4;
+        while (rem--)
+                iowrite32(MI_NOOP, virt++);
 
         ring->tail = 0;
         ring->space = ring_space(ring);
@@ -1427,20 +1419,13 @@ int intel_render_ring_init_dri(struct drm_device *dev, u64 start, u32 size)
         if (IS_I830(ring->dev))
                 ring->effective_size -= 128;
 
-        ring->map.offset = start;
-        ring->map.size = size;
-        ring->map.type = 0;
-        ring->map.flags = 0;
-        ring->map.mtrr = 0;
-
-        drm_core_ioremap_wc(&ring->map, dev);
-        if (ring->map.handle == NULL) {
+        ring->virtual_start = ioremap_wc(start, size);
+        if (ring->virtual_start == NULL) {
                 DRM_ERROR("can not ioremap virtual address for"
                           " ring buffer\n");
                 return -ENOMEM;
         }
 
-        ring->virtual_start = (void __force __iomem *)ring->map.handle;
         return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 7b879926969e..baba75714578 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -2,7 +2,7 @@
 #define _INTEL_RINGBUFFER_H_
 
 struct  intel_hw_status_page {
-        u32     __iomem *page_addr;
+        u32             *page_addr;
         unsigned int    gfx_addr;
         struct          drm_i915_gem_object *obj;
 };
@@ -115,7 +115,6 @@ struct  intel_ring_buffer {
         u32 outstanding_lazy_request;
 
         wait_queue_head_t irq_queue;
-        drm_local_map_t map;
 
         void *private;
 };
@@ -149,7 +148,9 @@ static inline u32
 intel_read_status_page(struct intel_ring_buffer *ring,
                        int reg)
 {
-        return ioread32(ring->status_page.page_addr + reg);
+        /* Ensure that the compiler doesn't optimize away the load. */
+        barrier();
+        return ring->status_page.page_addr[reg];
 }
 
 /**