Re: [PATCH v4] drm/i915: Use per device iommu check

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Nov 26, 2021 at 02:14:24PM +0000, Tvrtko Ursulin wrote:
From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>

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@xxxxxxxxx>
Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Acked-by: Robin Murphy <robin.murphy@xxxxxxx>
Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

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@xxxxxxxxx>


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




[Index of Archives]     [Linux DRI Users]     [Linux Intel Graphics]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux