drm/i915/gvt: introduce intel_vgpu_reset_mmio() to reset mmio space

This patch introduces a new function intel_vgpu_reset_mmio() to
reset vGPU MMIO space (virtual registers of the vGPU). The default
values are loaded as firmware during gvt inititiation.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

2 files changed, 26 insertions, 14 deletions

diff --git a/drivers/gpu/drm/i915/gvt/mmio.c b/drivers/gpu/drm/i915/gvt/mmio.c
index f7da735b7919..4df078bc5d04 100644
--- a/drivers/gpu/drm/i915/gvt/mmio.c
+++ b/drivers/gpu/drm/i915/gvt/mmio.c
@@ -304,6 +304,26 @@ err:
         return ret;
 }
 
+
+/**
+ * intel_vgpu_reset_mmio - reset virtual MMIO space
+ * @vgpu: a vGPU
+ *
+ */
+void intel_vgpu_reset_mmio(struct intel_vgpu *vgpu)
+{
+        struct intel_gvt *gvt = vgpu->gvt;
+        const struct intel_gvt_device_info *info = &gvt->device_info;
+
+        memcpy(vgpu->mmio.vreg, gvt->firmware.mmio, info->mmio_size);
+        memcpy(vgpu->mmio.sreg, gvt->firmware.mmio, info->mmio_size);
+
+        vgpu_vreg(vgpu, GEN6_GT_THREAD_STATUS_REG) = 0;
+
+        /* set the bit 0:2(Core C-State ) to C0 */
+        vgpu_vreg(vgpu, GEN6_GT_CORE_STATUS) = 0;
+}
+
 /**
  * intel_vgpu_init_mmio - init MMIO  space
  * @vgpu: a vGPU
@@ -315,22 +335,13 @@ int intel_vgpu_init_mmio(struct intel_vgpu *vgpu)
 {
         const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
 
-        if (vgpu->mmio.vreg)
-                memset(vgpu->mmio.vreg, 0, info->mmio_size * 2);
-        else {
-                vgpu->mmio.vreg = vzalloc(info->mmio_size * 2);
-                if (!vgpu->mmio.vreg)
-                        return -ENOMEM;
-        }
-        vgpu->mmio.sreg = vgpu->mmio.vreg + info->mmio_size;
+        vgpu->mmio.vreg = vzalloc(info->mmio_size * 2);
+        if (!vgpu->mmio.vreg)
+                return -ENOMEM;
 
-        memcpy(vgpu->mmio.vreg, vgpu->gvt->firmware.mmio, info->mmio_size);
-        memcpy(vgpu->mmio.sreg, vgpu->gvt->firmware.mmio, info->mmio_size);
-
-        vgpu_vreg(vgpu, GEN6_GT_THREAD_STATUS_REG) = 0;
+        vgpu->mmio.sreg = vgpu->mmio.vreg + info->mmio_size;
 
-        /* set the bit 0:2(Core C-State ) to C0 */
-        vgpu_vreg(vgpu, GEN6_GT_CORE_STATUS) = 0;
+        intel_vgpu_reset_mmio(vgpu);
 
         return 0;
 }
diff --git a/drivers/gpu/drm/i915/gvt/mmio.h b/drivers/gpu/drm/i915/gvt/mmio.h
index 1b74ac9650d5..3bc620f56f35 100644
--- a/drivers/gpu/drm/i915/gvt/mmio.h
+++ b/drivers/gpu/drm/i915/gvt/mmio.h
@@ -87,6 +87,7 @@ struct intel_gvt_mmio_info *intel_gvt_find_mmio_info(struct intel_gvt *gvt,
 })
 
 int intel_vgpu_init_mmio(struct intel_vgpu *vgpu);
+void intel_vgpu_reset_mmio(struct intel_vgpu *vgpu);
 void intel_vgpu_clean_mmio(struct intel_vgpu *vgpu);
 
 int intel_vgpu_gpa_to_mmio_offset(struct intel_vgpu *vgpu, u64 gpa);