diff mbox

[v6] drm/i915: enable to read CSB and CSB write pointer from HWSP in GVT-g VM

Message ID 1508039725-1066-1-git-send-email-weinan.z.li@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Li, Weinan Z Oct. 15, 2017, 3:55 a.m. UTC
Let GVT-g VM read the CSB and CSB write pointer from virtual HWSP, not all
the host support this feature, need to check the BIT(3) of caps in PVINFO.

v3 : Remove unnecessary comments.
v4 : Separate VM enable patch with GVT-g implementation patch due to code
dependency.
v5 : Use inline for GVT virtual HWSP caps check function.
v6 : Comments refine.

Signed-off-by: Weinan Li <weinan.z.li@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_pvinfo.h     | 1 +
 drivers/gpu/drm/i915/i915_vgpu.h       | 6 ++++++
 drivers/gpu/drm/i915/intel_engine_cs.c | 9 +++++----
 drivers/gpu/drm/i915/intel_lrc.c       | 1 -
 4 files changed, 12 insertions(+), 5 deletions(-)

Comments

Chris Wilson Oct. 15, 2017, 9:02 a.m. UTC | #1
Quoting Weinan Li (2017-10-15 04:55:25)
> Let GVT-g VM read the CSB and CSB write pointer from virtual HWSP, not all
> the host support this feature, need to check the BIT(3) of caps in PVINFO.
> 
> v3 : Remove unnecessary comments.
> v4 : Separate VM enable patch with GVT-g implementation patch due to code
> dependency.
> v5 : Use inline for GVT virtual HWSP caps check function.
> v6 : Comments refine.
> 
> Signed-off-by: Weinan Li <weinan.z.li@intel.com>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
Joonas Lahtinen Oct. 16, 2017, 11 a.m. UTC | #2
On Sun, 2017-10-15 at 10:02 +0100, Chris Wilson wrote:
> Quoting Weinan Li (2017-10-15 04:55:25)
> > Let GVT-g VM read the CSB and CSB write pointer from virtual HWSP, not all
> > the host support this feature, need to check the BIT(3) of caps in PVINFO.
> > 
> > v3 : Remove unnecessary comments.
> > v4 : Separate VM enable patch with GVT-g implementation patch due to code
> > dependency.
> > v5 : Use inline for GVT virtual HWSP caps check function.
> > v6 : Comments refine.
> > 
> > Signed-off-by: Weinan Li <weinan.z.li@intel.com>
> > Cc: Chris Wilson <chris@chris-wilson.co.uk>
> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> 
> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

Pushed the patch, thanks for supplying and reviewing it.

Regards, Joonas
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_pvinfo.h b/drivers/gpu/drm/i915/i915_pvinfo.h
index 0679a58..195203f 100644
--- a/drivers/gpu/drm/i915/i915_pvinfo.h
+++ b/drivers/gpu/drm/i915/i915_pvinfo.h
@@ -53,6 +53,7 @@  enum vgt_g2v_type {
  * VGT capabilities type
  */
 #define VGT_CAPS_FULL_48BIT_PPGTT	BIT(2)
+#define VGT_CAPS_HWSP_EMULATION		BIT(3)
 
 struct vgt_if {
 	u64 magic;		/* VGT_MAGIC */
diff --git a/drivers/gpu/drm/i915/i915_vgpu.h b/drivers/gpu/drm/i915/i915_vgpu.h
index b72bd29..bb83384 100644
--- a/drivers/gpu/drm/i915/i915_vgpu.h
+++ b/drivers/gpu/drm/i915/i915_vgpu.h
@@ -30,6 +30,12 @@ 
 
 bool intel_vgpu_has_full_48bit_ppgtt(struct drm_i915_private *dev_priv);
 
+static inline bool
+intel_vgpu_has_hwsp_emulation(struct drm_i915_private *dev_priv)
+{
+	return dev_priv->vgpu.caps & VGT_CAPS_HWSP_EMULATION;
+}
+
 int intel_vgt_balloon(struct drm_i915_private *dev_priv);
 void intel_vgt_deballoon(struct drm_i915_private *dev_priv);
 
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index a59b2a3..83e696f 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -25,6 +25,7 @@ 
 #include <drm/drm_print.h>
 
 #include "i915_drv.h"
+#include "i915_vgpu.h"
 #include "intel_ringbuffer.h"
 #include "intel_lrc.h"
 
@@ -386,10 +387,6 @@  static void intel_engine_init_timeline(struct intel_engine_cs *engine)
 
 static bool csb_force_mmio(struct drm_i915_private *i915)
 {
-	/* GVT emulation depends upon intercepting CSB mmio */
-	if (intel_vgpu_active(i915))
-		return true;
-
 	/*
 	 * IOMMU adds unpredictable latency causing the CSB write (from the
 	 * GPU into the HWSP) to only be visible some time after the interrupt
@@ -398,6 +395,10 @@  static bool csb_force_mmio(struct drm_i915_private *i915)
 	if (intel_vtd_active())
 		return true;
 
+	/* Older GVT emulation depends upon intercepting CSB mmio */
+	if (intel_vgpu_active(i915) && !intel_vgpu_has_hwsp_emulation(i915))
+		return true;
+
 	return false;
 }
 
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index fbfcf88..766552f 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -793,7 +793,6 @@  static void intel_lrc_irq_handler(unsigned long data)
 			&engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX];
 		unsigned int head, tail;
 
-		/* However GVT emulation depends upon intercepting CSB mmio */
 		if (unlikely(execlists->csb_use_mmio)) {
 			buf = (u32 * __force)
 				(dev_priv->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_BUF_LO(engine, 0)));