[PATCH 2/3] i915/gvt: save the initial HW state snapshot in i915.

From: Zhi Wang
Date: Mon Nov 08 2021 - 16:27:27 EST


From: Zhi Wang <zhi.wang.linux@xxxxxxxxx>

Save the inital HW state snapshot in i915 so that the rest code of GVT-g
can be moved into a dedicated module while it can still get a clean
initial HW state saved at the correct time during the initialization of
i915. The futhrer vGPU created by GVT-g will use this HW state as the
initial HW state.

Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Cc: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
Cc: Zhi Wang <zhi.a.wang@xxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Zhi Wang <zhi.wang.linux@xxxxxxxxx>
---
drivers/gpu/drm/i915/gvt/gvt.c | 31 +------------
drivers/gpu/drm/i915/gvt/gvt.h | 6 +++
drivers/gpu/drm/i915/intel_gvt.c | 75 ++++++++++++++++++++++++++++++--
3 files changed, 80 insertions(+), 32 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c
index cbac409f6c8a..4b3b47892453 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.c
+++ b/drivers/gpu/drm/i915/gvt/gvt.c
@@ -63,23 +63,6 @@ static const struct intel_gvt_ops intel_gvt_ops = {
.emulate_hotplug = intel_vgpu_emulate_hotplug,
};

-static void init_device_info(struct intel_gvt *gvt)
-{
- struct intel_gvt_device_info *info = &gvt->device_info;
- struct pci_dev *pdev = to_pci_dev(gvt->gt->i915->drm.dev);
-
- info->max_support_vgpus = 8;
- info->cfg_space_size = PCI_CFG_SPACE_EXP_SIZE;
- info->mmio_size = 2 * 1024 * 1024;
- info->mmio_bar = 0;
- info->gtt_start_offset = 8 * 1024 * 1024;
- info->gtt_entry_size = 8;
- info->gtt_entry_size_shift = 3;
- info->gmadr_bytes_in_cmd = 8;
- info->max_surface_size = 36 * 1024 * 1024;
- info->msi_cap_offset = pdev->msi_cap;
-}
-
static void intel_gvt_test_and_emulate_vblank(struct intel_gvt *gvt)
{
struct intel_vgpu *vgpu;
@@ -188,27 +171,19 @@ void intel_gvt_clean_device(struct drm_i915_private *i915)
*/
int intel_gvt_init_device(struct drm_i915_private *i915)
{
- struct intel_gvt *gvt;
+ struct intel_gvt *gvt = i915->gvt;
struct intel_vgpu *vgpu;
int ret;

- if (drm_WARN_ON(&i915->drm, i915->gvt))
+ if (drm_WARN_ON(&i915->drm, !i915->gvt))
return -EEXIST;

- gvt = kzalloc(sizeof(struct intel_gvt), GFP_KERNEL);
- if (!gvt)
- return -ENOMEM;
-
gvt_dbg_core("init gvt device\n");

idr_init_base(&gvt->vgpu_idr, 1);
spin_lock_init(&gvt->scheduler.mmio_context_lock);
mutex_init(&gvt->lock);
mutex_init(&gvt->sched_lock);
- gvt->gt = &i915->gt;
- i915->gvt = gvt;
-
- init_device_info(gvt);

ret = intel_gvt_setup_mmio_info(gvt);
if (ret)
@@ -281,8 +256,6 @@ int intel_gvt_init_device(struct drm_i915_private *i915)
intel_gvt_clean_mmio_info(gvt);
out_clean_idr:
idr_destroy(&gvt->vgpu_idr);
- kfree(gvt);
- i915->gvt = NULL;
return ret;
}

diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 0c0615602343..1defee730cf3 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -296,6 +296,11 @@ struct intel_vgpu_type {
enum intel_vgpu_edid resolution;
};

+struct intel_gvt_hw_state {
+ void *cfg_space;
+ void *mmio;
+};
+
struct intel_gvt {
/* GVT scope lock, protect GVT itself, and all resource currently
* not yet protected by special locks(vgpu and scheduler lock).
@@ -311,6 +316,7 @@ struct intel_gvt {
struct intel_gvt_gm gm;
struct intel_gvt_fence fence;
struct intel_gvt_mmio mmio;
+ struct intel_gvt_hw_state hw_state;
struct intel_gvt_firmware firmware;
struct intel_gvt_irq irq;
struct intel_gvt_gtt gtt;
diff --git a/drivers/gpu/drm/i915/intel_gvt.c b/drivers/gpu/drm/i915/intel_gvt.c
index 64846d9bff0b..4fd51974bd35 100644
--- a/drivers/gpu/drm/i915/intel_gvt.c
+++ b/drivers/gpu/drm/i915/intel_gvt.c
@@ -87,8 +87,12 @@ void intel_gvt_sanitize_options(struct drm_i915_private *dev_priv)
}

#define GENERATE_MMIO_TABLE_IN_I915
-static int new_mmio_info(struct intel_gvt *gvt, u64 offset)
+static int new_mmio_info(struct intel_gvt *gvt, u32 offset)
{
+ void *mmio = gvt->hw_state.mmio;
+
+ *(u32 *)(mmio + offset) = intel_uncore_read_notrace(gvt->gt->uncore,
+ _MMIO(offset));
return 0;
}

@@ -96,6 +100,22 @@ static int new_mmio_info(struct intel_gvt *gvt, u64 offset)
#include "gvt/mmio_table.h"
#undef GENERATE_MMIO_TABLE_IN_I915

+static void init_device_info(struct intel_gvt *gvt)
+{
+ struct intel_gvt_device_info *info = &gvt->device_info;
+ struct pci_dev *pdev = to_pci_dev(gvt->gt->i915->drm.dev);
+
+ info->max_support_vgpus = 8;
+ info->cfg_space_size = PCI_CFG_SPACE_EXP_SIZE;
+ info->mmio_size = 2 * 1024 * 1024;
+ info->mmio_bar = 0;
+ info->gtt_start_offset = 8 * 1024 * 1024;
+ info->gtt_entry_size = 8;
+ info->gtt_entry_size_shift = 3;
+ info->gmadr_bytes_in_cmd = 8;
+ info->max_surface_size = 36 * 1024 * 1024;
+ info->msi_cap_offset = pdev->msi_cap;
+}

/**
* intel_gvt_init - initialize GVT components
@@ -109,7 +129,13 @@ static int new_mmio_info(struct intel_gvt *gvt, u64 offset)
*/
int intel_gvt_init(struct drm_i915_private *dev_priv)
{
+ struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
+ struct intel_gvt *gvt = NULL;
+ struct intel_gvt_hw_state *hw_state;
+ struct intel_gvt_device_info *info;
+ void *mem;
int ret;
+ int i;

if (i915_inject_probe_failure(dev_priv))
return -ENODEV;
@@ -123,17 +149,54 @@ int intel_gvt_init(struct drm_i915_private *dev_priv)
if (intel_uc_wants_guc_submission(&dev_priv->gt.uc)) {
drm_err(&dev_priv->drm,
"i915 GVT-g loading failed due to Graphics virtualization is not yet supported with GuC submission\n");
- return -EIO;
+ goto bail;
}

+ gvt = kzalloc(sizeof(struct intel_gvt), GFP_KERNEL);
+ if (!gvt)
+ goto bail;
+
+ gvt->gt = &dev_priv->gt;
+ hw_state = &gvt->hw_state;
+ info = &gvt->device_info;
+
+ init_device_info(gvt);
+
+ mem = kmalloc(info->cfg_space_size, GFP_KERNEL);
+ if (!mem)
+ goto err_cfg_space;
+
+ hw_state->cfg_space = mem;
+
+ mem = vmalloc(info->mmio_size);
+ if (!mem)
+ goto err_mmio;
+
+ hw_state->mmio = mem;
+
+ for (i = 0; i < PCI_CFG_SPACE_EXP_SIZE; i += 4)
+ pci_read_config_dword(pdev, i, hw_state->cfg_space + i);
+
+ ret = intel_gvt_init_mmio_info(gvt);
+ if (ret)
+ goto err_mmio_info;
+
+ dev_priv->gvt = gvt;
+
ret = intel_gvt_init_device(dev_priv);
if (ret) {
drm_dbg(&dev_priv->drm, "Fail to init GVT device\n");
- goto bail;
+ goto err_mmio_info;
}

return 0;

+err_mmio_info:
+ vfree(hw_state->mmio);
+err_mmio:
+ kfree(hw_state->cfg_space);
+err_cfg_space:
+ kfree(gvt);
bail:
dev_priv->params.enable_gvt = 0;
return 0;
@@ -154,10 +217,16 @@ static inline bool intel_gvt_active(struct drm_i915_private *dev_priv)
*/
void intel_gvt_driver_remove(struct drm_i915_private *dev_priv)
{
+ struct intel_gvt *gvt = dev_priv->gvt;
+
if (!intel_gvt_active(dev_priv))
return;

+ kfree(gvt->hw_state.cfg_space);
+ vfree(gvt->hw_state.mmio);
intel_gvt_clean_device(dev_priv);
+ kfree(gvt);
+ dev_priv->gvt = NULL;
}

/**
--
2.25.1