On Fri, Nov 26, 2021 at 02:14:24PM +0000, Tvrtko Ursulin wrote:

From: Tvrtko Ursulin tvrtko.ursulin@intel.com

With both integrated and discrete Intel GPUs in a system, the current global check of intel_iommu_gfx_mapped, as done from intel_vtd_active() may not be completely accurate.

In this patch we add i915 parameter to intel_vtd_active() in order to prepare it for multiple GPUs and we also change the check away from Intel specific intel_iommu_gfx_mapped (global exported by the Intel IOMMU driver) to probing the presence of IOMMU on a specific device using device_iommu_mapped().

This will return true both for IOMMU pass-through and address translation modes which matches the current behaviour. If in the future we wanted to distinguish between these two modes we could either use iommu_get_domain_for_dev() and check for __IOMMU_DOMAIN_PAGING bit indicating address translation, or ask for a new API to be exported from the IOMMU core code.

v2:

• Check for dmar translation specifically, not just iommu domain. (Baolu)

v3:

• Go back to plain "any domain" check for now, rewrite commit message.

v4:

• Use device_iommu_mapped. (Robin, Baolu)

Signed-off-by: Tvrtko Ursulin tvrtko.ursulin@intel.com Cc: Lu Baolu baolu.lu@linux.intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Robin Murphy robin.murphy@arm.com Acked-by: Robin Murphy robin.murphy@arm.com Reviewed-by: Lu Baolu baolu.lu@linux.intel.com

this last version looks pretty clean.

Also, for patches touching gem / gt we should Cc dri-devel. I'm leaving the patch below for reference and Cc'ing it. Small nit below, but can be ignored.

---

drivers/gpu/drm/i915/display/intel_bw.c | 2 +- drivers/gpu/drm/i915/display/intel_display.c | 2 +- drivers/gpu/drm/i915/display/intel_fbc.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 2 +- drivers/gpu/drm/i915/gem/i915_gemfs.c | 2 +- drivers/gpu/drm/i915/gt/intel_ggtt.c | 4 ++-- drivers/gpu/drm/i915/i915_debugfs.c | 1 + drivers/gpu/drm/i915/i915_driver.c | 7 +++++++ drivers/gpu/drm/i915/i915_drv.h | 13 +++++++------ drivers/gpu/drm/i915/i915_gpu_error.c | 5 +---- drivers/gpu/drm/i915/intel_device_info.c | 14 +------------- drivers/gpu/drm/i915/intel_pm.c | 2 +- 12 files changed, 25 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c index abec394f6869..2da4aacc956b 100644 --- a/drivers/gpu/drm/i915/display/intel_bw.c +++ b/drivers/gpu/drm/i915/display/intel_bw.c @@ -634,7 +634,7 @@ static unsigned int intel_bw_data_rate(struct drm_i915_private *dev_priv, for_each_pipe(dev_priv, pipe) data_rate += bw_state->data_rate[pipe];

• if (DISPLAY_VER(dev_priv) >= 13 && intel_vtd_active())

• if (DISPLAY_VER(dev_priv) >= 13 && intel_vtd_active(dev_priv)) data_rate = data_rate * 105 / 100;

  return data_rate;

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index b2d51cd79d6c..1ef77ba7f645 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -1293,7 +1293,7 @@ static bool needs_async_flip_vtd_wa(const struct intel_crtc_state *crtc_state) { struct drm_i915_private *i915 = to_i915(crtc_state->uapi.crtc->dev);

• return crtc_state->uapi.async_flip && intel_vtd_active() &&

• return crtc_state->uapi.async_flip && intel_vtd_active(i915) && (DISPLAY_VER(i915) == 9 || IS_BROADWELL(i915) || IS_HASWELL(i915));

}

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c index d0c34bc3af6c..614e8697c068 100644 --- a/drivers/gpu/drm/i915/display/intel_fbc.c +++ b/drivers/gpu/drm/i915/display/intel_fbc.c @@ -1677,7 +1677,7 @@ static int intel_sanitize_fbc_option(struct drm_i915_private *i915) static bool need_fbc_vtd_wa(struct drm_i915_private *i915) { /* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */

• if (intel_vtd_active() &&

• if (intel_vtd_active(i915) && (IS_SKYLAKE(i915) || IS_BROXTON(i915))) { drm_info(&i915->drm, "Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c index 80680395bb3b..bce03d74a0b4 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c @@ -399,7 +399,7 @@ static int i915_gem_init_stolen(struct intel_memory_region *mem) return 0; }

• if (intel_vtd_active() && GRAPHICS_VER(i915) < 8) {

• if (intel_vtd_active(i915) && GRAPHICS_VER(i915) < 8) { drm_notice(&i915->drm, "%s, disabling use of stolen memory\n", "DMAR active");

diff --git a/drivers/gpu/drm/i915/gem/i915_gemfs.c b/drivers/gpu/drm/i915/gem/i915_gemfs.c index dbdbdc344d87..11cd66d183e6 100644 --- a/drivers/gpu/drm/i915/gem/i915_gemfs.c +++ b/drivers/gpu/drm/i915/gem/i915_gemfs.c @@ -31,7 +31,7 @@ int i915_gemfs_init(struct drm_i915_private *i915) */

opts = NULL;

• if (intel_vtd_active()) {

• if (intel_vtd_active(i915)) { if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { static char huge_opt[] = "huge=within_size"; /* r/w */

diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c index 555111c3bee5..110d3944f9a2 100644 --- a/drivers/gpu/drm/i915/gt/intel_ggtt.c +++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c @@ -106,7 +106,7 @@ static bool needs_idle_maps(struct drm_i915_private *i915) * Query intel_iommu to see if we need the workaround. Presumably that * was loaded first. */

• if (!intel_vtd_active())

• if (!intel_vtd_active(i915)) return false;

  if (GRAPHICS_VER(i915) == 5 && IS_MOBILE(i915))

@@ -1233,7 +1233,7 @@ int i915_ggtt_probe_hw(struct drm_i915_private *i915) if (ret) return ret;

• if (intel_vtd_active())

• if (intel_vtd_active(i915)) drm_info(&i915->drm, "VT-d active for gfx access\n");

  return 0;

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index fe638b5da7c0..390d541f64ea 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -65,6 +65,7 @@ static int i915_capabilities(struct seq_file *m, void *data)

intel_device_info_print_static(INTEL_INFO(i915), &p); intel_device_info_print_runtime(RUNTIME_INFO(i915), &p);

• i915_print_iommu_status(i915, &p);

following the surrounding code, maybe this should be intel_driver_print_iommu_status()?

Reviewed-by: Lucas De Marchi lucas.demarchi@intel.com

thanks Lucas De Marchi

intel_gt_info_print(&i915->gt.info, &p); intel_driver_caps_print(&i915->caps, &p);

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c index a13666627dad..bbc99fc5888f 100644 --- a/drivers/gpu/drm/i915/i915_driver.c +++ b/drivers/gpu/drm/i915/i915_driver.c @@ -741,6 +741,12 @@ static void i915_driver_unregister(struct drm_i915_private *dev_priv) i915_gem_driver_unregister(dev_priv); }

+void +i915_print_iommu_status(struct drm_i915_private *i915, struct drm_printer *p) +{

• drm_printf(p, "iommu: %s\n", enableddisabled(intel_vtd_active(i915)));

+}

static void i915_welcome_messages(struct drm_i915_private *dev_priv) { if (drm_debug_enabled(DRM_UT_DRIVER)) { @@ -756,6 +762,7 @@ static void i915_welcome_messages(struct drm_i915_private *dev_priv)

intel_device_info_print_static(INTEL_INFO(dev_priv), &p);
intel_device_info_print_runtime(RUNTIME_INFO(dev_priv), &p);

• i915_print_iommu_status(dev_priv, &p);
  

  intel_gt_info_print(&dev_priv->gt.info, &p); }

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 1bfadd9127fc..d99e020773ac 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1760,26 +1760,27 @@ static inline bool run_as_guest(void) #define HAS_D12_PLANE_MINIMIZATION(dev_priv) (IS_ROCKETLAKE(dev_priv) || \ IS_ALDERLAKE_S(dev_priv))

-static inline bool intel_vtd_active(void) +static inline bool intel_vtd_active(struct drm_i915_private *i915) { -#ifdef CONFIG_INTEL_IOMMU

• if (intel_iommu_gfx_mapped)

• if (device_iommu_mapped(i915->drm.dev)) return true;

-#endif

/* Running as a guest, we assume the host is enforcing VT'd */ return run_as_guest(); }

+void +i915_print_iommu_status(struct drm_i915_private *i915, struct drm_printer *p);

static inline bool intel_scanout_needs_vtd_wa(struct drm_i915_private *dev_priv) {

• return GRAPHICS_VER(dev_priv) >= 6 && intel_vtd_active();

• return GRAPHICS_VER(dev_priv) >= 6 && intel_vtd_active(dev_priv);

}

static inline bool intel_ggtt_update_needs_vtd_wa(struct drm_i915_private *i915) {

• return IS_BROXTON(i915) && intel_vtd_active();

• return IS_BROXTON(i915) && intel_vtd_active(i915);

}

static inline bool diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index b1e4ce0f798f..a485aa4ca669 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -1754,10 +1754,7 @@ static void capture_gen(struct i915_gpu_coredump *error) error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count); error->suspended = i915->runtime_pm.suspended;

• error->iommu = -1;

-#ifdef CONFIG_INTEL_IOMMU

• error->iommu = intel_iommu_gfx_mapped;

-#endif

• error->iommu = intel_vtd_active(i915); error->reset_count = i915_reset_count(&i915->gpu_error); error->suspend_count = i915->suspend_count;

diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c index 6e6b317bc33c..e6605b5181a5 100644 --- a/drivers/gpu/drm/i915/intel_device_info.c +++ b/drivers/gpu/drm/i915/intel_device_info.c @@ -83,17 +83,6 @@ const char *intel_platform_name(enum intel_platform platform) return platform_names[platform]; }

-static const char *iommu_name(void) -{

• const char *msg = "n/a";

-#ifdef CONFIG_INTEL_IOMMU

• msg = enableddisabled(intel_iommu_gfx_mapped);

-#endif

• return msg;

-}

void intel_device_info_print_static(const struct intel_device_info *info, struct drm_printer *p) { @@ -114,7 +103,6 @@ void intel_device_info_print_static(const struct intel_device_info *info, drm_printf(p, "display version: %u\n", info->display.ver);

drm_printf(p, "gt: %d\n", info->gt);

• drm_printf(p, "iommu: %s\n", iommu_name()); drm_printf(p, "memory-regions: %x\n", info->memory_regions); drm_printf(p, "page-sizes: %x\n", info->page_sizes); drm_printf(p, "platform: %s\n", intel_platform_name(info->platform));

@@ -374,7 +362,7 @@ void intel_device_info_runtime_init(struct drm_i915_private *dev_priv) info->display.has_dsc = 0; }

• if (GRAPHICS_VER(dev_priv) == 6 && intel_vtd_active()) {

• if (GRAPHICS_VER(dev_priv) == 6 && intel_vtd_active(dev_priv)) { drm_info(&dev_priv->drm, "Disabling ppGTT for VT-d support\n"); info->ppgtt_type = INTEL_PPGTT_NONE;

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 01fa3fac1b57..cff0f32bedc9 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -98,7 +98,7 @@ static void gen9_init_clock_gating(struct drm_i915_private *dev_priv) * "Plane N strech max must be programmed to 11b (x1) * when Async flips are enabled on that plane." */

• if (!IS_GEMINILAKE(dev_priv) && intel_vtd_active())
  

• if (!IS_GEMINILAKE(dev_priv) && intel_vtd_active(dev_priv))
  intel_uncore_rmw(&dev_priv->uncore, CHICKEN_PIPESL_1(pipe),
  		 SKL_PLANE1_STRETCH_MAX_MASK, SKL_PLANE1_STRETCH_MAX_X1);
  

  }

-- 2.32.0