[Intel-gfx] [PATCH 1/5] drm/i915: make intel_gvt_init() later instead of too early

[Zhenyu Wang]

Previously intel_gvt_init() was called very early even before
MMIO initialization which had several drawbacks:
- Have to handle MMIO access for initial MMIO state dump if golden
  state firmware is not available
- Hypervisor detection should depend on pvinfo only instead of detecting
  hypervisor status.
- Don't know hw resource size e.g aperture, ggtt size to determine
  for vGPU type, etc.

This trys to move intel_gvt_init() call late after required info
has already been initialized for GVT host.

Signed-off-by: Zhenyu Wang <zhenyuw at linux.intel.com>
---
 drivers/gpu/drm/i915/gvt/gvt.c   | 20 ++++++++------------
 drivers/gpu/drm/i915/i915_drv.c  | 14 +++++++-------
 drivers/gpu/drm/i915/intel_gvt.c |  5 +++++
 3 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c
index e6bf5c533fbe..35264a991776 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.c
+++ b/drivers/gpu/drm/i915/gvt/gvt.c
@@ -73,23 +73,19 @@ int intel_gvt_init_host(void)
 	if (intel_gvt_host.initialized)
 		return 0;
 
-	/* Xen DOM U */
-	if (xen_domain() && !xen_initial_domain())
-		return -ENODEV;
-
 	/* Try to load MPT modules for hypervisors */
-	if (xen_initial_domain()) {
+#if IS_ENABLED(CONFIG_DRM_I915_GVT_KVMGT)
+	/* Try KVMGT */
+	intel_gvt_host.mpt = try_then_request_module(
+		symbol_get(kvmgt_mpt), "kvmgt");
+	intel_gvt_host.hypervisor_type = INTEL_GVT_HYPERVISOR_KVM;
+#endif
+
+	if (!intel_gvt_host.mpt && xen_initial_domain()) {
 		/* In Xen dom0 */
 		intel_gvt_host.mpt = try_then_request_module(
 				symbol_get(xengt_mpt), "xengt");
 		intel_gvt_host.hypervisor_type = INTEL_GVT_HYPERVISOR_XEN;
-	} else {
-#if IS_ENABLED(CONFIG_DRM_I915_GVT_KVMGT)
-		/* not in Xen. Try KVMGT */
-		intel_gvt_host.mpt = try_then_request_module(
-				symbol_get(kvmgt_mpt), "kvmgt");
-		intel_gvt_host.hypervisor_type = INTEL_GVT_HYPERVISOR_KVM;
-#endif
 	}
 
 	/* Fail to load MPT modules - bail out */
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 4d22b4b479b8..9270dda354db 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -815,10 +815,6 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
 	if (ret < 0)
 		return ret;
 
-	ret = intel_gvt_init(dev_priv);
-	if (ret < 0)
-		goto err_workqueues;
-
 	/* This must be called before any calls to HAS_PCH_* */
 	intel_detect_pch(dev_priv);
 
@@ -832,7 +828,7 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
 	intel_init_audio_hooks(dev_priv);
 	ret = i915_gem_load_init(dev_priv);
 	if (ret < 0)
-		goto err_gvt;
+		goto err_workqueues;
 
 	intel_display_crc_init(dev_priv);
 
@@ -844,8 +840,6 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
 
 	return 0;
 
-err_gvt:
-	intel_gvt_cleanup(dev_priv);
 err_workqueues:
 	i915_workqueues_cleanup(dev_priv);
 	return ret;
@@ -1068,6 +1062,10 @@ static int i915_driver_init_hw(struct drm_i915_private *dev_priv)
 			DRM_DEBUG_DRIVER("can't enable MSI");
 	}
 
+	ret = intel_gvt_init(dev_priv);
+	if (ret)
+		goto out_ggtt;
+
 	return 0;
 
 out_ggtt:
@@ -1281,6 +1279,8 @@ void i915_driver_unload(struct drm_device *dev)
 
 	intel_display_power_get(dev_priv, POWER_DOMAIN_INIT);
 
+	intel_gvt_cleanup(dev_priv);
+
 	i915_driver_unregister(dev_priv);
 
 	drm_vblank_cleanup(dev);
diff --git a/drivers/gpu/drm/i915/intel_gvt.c b/drivers/gpu/drm/i915/intel_gvt.c
index 290384e86c63..d23c0fcff751 100644
--- a/drivers/gpu/drm/i915/intel_gvt.c
+++ b/drivers/gpu/drm/i915/intel_gvt.c
@@ -67,6 +67,11 @@ int intel_gvt_init(struct drm_i915_private *dev_priv)
 		return 0;
 	}
 
+	if (intel_vgpu_active(dev_priv)) {
+		DRM_DEBUG_DRIVER("GVT-g is disabled for guest\n");
+		goto bail;
+	}
+
 	if (!is_supported_device(dev_priv)) {
 		DRM_DEBUG_DRIVER("Unsupported device. GVT-g is disabled\n");
 		goto bail;
-- 
2.11.0