[PATCH 2/2] drm/i915/gvt: fix compilation

From: Arnd Bergmann
Date: Fri Oct 21 2016 - 11:27:58 EST


Two functions in the newly added gvt render code are obviously
broken, as they reference a variable without initialization and
don't reference another variable at all:

drivers/gpu/drm/i915/gvt/render.c: In function âintel_gvt_load_render_mmioâ:
drivers/gpu/drm/i915/gvt/render.c:148:13: error: âoffset.regâ may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/gpu/drm/i915/gvt/render.c: In function âintel_gvt_restore_render_mmioâ:
drivers/gpu/drm/i915/gvt/render.c:185:13: error: âoffset.regâ may be used uninitialized in this function [-Werror=maybe-uninitialized]

This is probably not a correct fix, but it gets us a clean build
by removing the unused arrays and initializing the offset variable
to something that potentially might be correct.

Fixes: 178657139307 ("drm/i915/gvt: vGPU context switch")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/gpu/drm/i915/gvt/render.c | 25 +++----------------------
1 file changed, 3 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/render.c b/drivers/gpu/drm/i915/gvt/render.c
index feebb65ba641..79e112288065 100644
--- a/drivers/gpu/drm/i915/gvt/render.c
+++ b/drivers/gpu/drm/i915/gvt/render.c
@@ -147,29 +147,20 @@ static void load_mocs(struct intel_vgpu *vgpu, int ring_id)
{
struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
i915_reg_t offset, l3_offset;
- u32 regs[] = {
- [RCS] = 0xc800,
- [VCS] = 0xc900,
- [VCS2] = 0xca00,
- [BCS] = 0xcc00,
- [VECS] = 0xcb00,
- };
int i;

- if (WARN_ON(ring_id >= ARRAY_SIZE(regs)))
- return;
-
if (!IS_SKYLAKE(dev_priv))
return;

for (i = 0; i < 64; i++) {
+ offset.reg = i * 4;
gen9_render_mocs[ring_id][i] = I915_READ(offset);
I915_WRITE(offset, vgpu_vreg(vgpu, offset));
POSTING_READ(offset);
- offset.reg += 4;
}

if (ring_id == RCS) {
+ offset.reg = 64 * 4;
l3_offset.reg = 0xb020;
for (i = 0; i < 32; i++) {
gen9_render_mocs_L3[i] = I915_READ(l3_offset);
@@ -184,26 +175,16 @@ static void restore_mocs(struct intel_vgpu *vgpu, int ring_id)
{
struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
i915_reg_t offset, l3_offset;
- u32 regs[] = {
- [RCS] = 0xc800,
- [VCS] = 0xc900,
- [VCS2] = 0xca00,
- [BCS] = 0xcc00,
- [VECS] = 0xcb00,
- };
int i;

- if (WARN_ON(ring_id >= ARRAY_SIZE(regs)))
- return;
-
if (!IS_SKYLAKE(dev_priv))
return;

for (i = 0; i < 64; i++) {
+ offset.reg = i * 4;
vgpu_vreg(vgpu, offset) = I915_READ(offset);
I915_WRITE(offset, gen9_render_mocs[ring_id][i]);
POSTING_READ(offset);
- offset.reg += 4;
}

if (ring_id == RCS) {
--
2.9.0