[PATCH 3/4] drm/xe: Wire up device shutdown handler

[Lucas De Marchi]

On Thu, Sep 05, 2024 at 05:00:51PM GMT, Maarten Lankhorst wrote:
>The system is turning off, and we should probably put the device
>in a safe power state. We don't need to evict VRAM or suspend running
>jobs to a safe state, as the device is rebooted anyway.
>
>This does not imply the system is necessarily reset, as we can
>kexec into a new kernel. Without shutting down, things like
>USB Type-C may mysteriously start failing.
>
>References: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/3500
>Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>---
> drivers/gpu/drm/xe/display/xe_display.c | 43 +++++++++++++++++++++++++
> drivers/gpu/drm/xe/display/xe_display.h |  4 +++
> drivers/gpu/drm/xe/xe_device.c          | 40 +++++++++++++++++++----
> drivers/gpu/drm/xe/xe_gt.c              |  7 ++++
> drivers/gpu/drm/xe/xe_gt.h              |  1 +
> 5 files changed, 89 insertions(+), 6 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/display/xe_display.c b/drivers/gpu/drm/xe/display/xe_display.c
>index 33071ac3bc12d..0cb8eef1b095c 100644
>--- a/drivers/gpu/drm/xe/display/xe_display.c
>+++ b/drivers/gpu/drm/xe/display/xe_display.c
>@@ -350,6 +350,36 @@ void xe_display_pm_suspend(struct xe_device *xe)
> 	__xe_display_pm_suspend(xe, false);
> }
>
>+void xe_display_pm_shutdown(struct xe_device *xe)
>+{
>+	struct intel_display *display = &xe->display;
>+
>+	if (!xe->info.probe_display)
>+		return;
>+
>+	intel_power_domains_disable(xe);
>+	intel_fbdev_set_suspend(&xe->drm, FBINFO_STATE_SUSPENDED, true);
>+	if (has_display(xe)) {
>+		drm_kms_helper_poll_disable(&xe->drm);
>+		intel_display_driver_disable_user_access(xe);
>+		intel_display_driver_suspend(xe);
>+	}
>+
>+	xe_display_flush_cleanup_work(xe);
>+	intel_dp_mst_suspend(xe);
>+	intel_hpd_cancel_work(xe);
>+
>+	if (has_display(xe))
>+		intel_display_driver_suspend_access(xe);
>+
>+	intel_encoder_suspend_all(display);
>+	intel_encoder_shutdown_all(display);
>+
>+	intel_opregion_suspend(display, PCI_D3cold);
>+
>+	intel_dmc_suspend(xe);
>+}
>+
> void xe_display_pm_runtime_suspend(struct xe_device *xe)
> {
> 	if (!xe->info.probe_display)
>@@ -372,6 +402,19 @@ void xe_display_pm_suspend_late(struct xe_device *xe)
> 	intel_display_power_suspend_late(xe);
> }
>
>+void xe_display_pm_shutdown_late(struct xe_device *xe)
>+{
>+	if (!xe->info.probe_display)
>+		return;
>+
>+	/*
>+	 * The only requirement is to reboot with display DC states disabled,
>+	 * for now leaving all display power wells in the INIT power domain
>+	 * enabled.
>+	 */
>+	intel_power_domains_driver_remove(xe);
>+}
>+
> void xe_display_pm_resume_early(struct xe_device *xe)
> {
> 	if (!xe->info.probe_display)
>diff --git a/drivers/gpu/drm/xe/display/xe_display.h b/drivers/gpu/drm/xe/display/xe_display.h
>index bed55fd26f304..17afa537aee50 100644
>--- a/drivers/gpu/drm/xe/display/xe_display.h
>+++ b/drivers/gpu/drm/xe/display/xe_display.h
>@@ -35,7 +35,9 @@ void xe_display_irq_reset(struct xe_device *xe);
> void xe_display_irq_postinstall(struct xe_device *xe, struct xe_gt *gt);
>
> void xe_display_pm_suspend(struct xe_device *xe);
>+void xe_display_pm_shutdown(struct xe_device *xe);
> void xe_display_pm_suspend_late(struct xe_device *xe);
>+void xe_display_pm_shutdown_late(struct xe_device *xe);
> void xe_display_pm_resume_early(struct xe_device *xe);
> void xe_display_pm_resume(struct xe_device *xe);
> void xe_display_pm_runtime_suspend(struct xe_device *xe);
>@@ -66,7 +68,9 @@ static inline void xe_display_irq_reset(struct xe_device *xe) {}
> static inline void xe_display_irq_postinstall(struct xe_device *xe, struct xe_gt *gt) {}
>
> static inline void xe_display_pm_suspend(struct xe_device *xe) {}
>+static inline void xe_display_pm_shutdown(struct xe_device *xe) {}
> static inline void xe_display_pm_suspend_late(struct xe_device *xe) {}
>+static inline void xe_display_pm_shutdown_late(struct xe_device *xe) {}
> static inline void xe_display_pm_resume_early(struct xe_device *xe) {}
> static inline void xe_display_pm_resume(struct xe_device *xe) {}
> static inline void xe_display_pm_runtime_suspend(struct xe_device *xe) {}
>diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
>index 1a0d7fdd094b5..a2ce7454794f6 100644
>--- a/drivers/gpu/drm/xe/xe_device.c
>+++ b/drivers/gpu/drm/xe/xe_device.c
>@@ -383,6 +383,11 @@ struct xe_device *xe_device_create(struct pci_dev *pdev,
> 	return ERR_PTR(err);
> }
>
>+static bool xe_driver_flr_disabled(struct xe_device *xe)
>+{
>+	return xe_mmio_read32(xe_root_mmio_gt(xe), GU_CNTL_PROTECTED) & DRIVERINT_FLR_DIS;
>+}
>+
> /*
>  * The driver-initiated FLR is the highest level of reset that we can trigger
>  * from within the driver. It is different from the PCI FLR in that it doesn't
>@@ -396,17 +401,12 @@ struct xe_device *xe_device_create(struct pci_dev *pdev,
>  * if/when a new instance of i915 is bound to the device it will do a full
>  * re-init anyway.
>  */
>-static void xe_driver_flr(struct xe_device *xe)
>+static void __xe_driver_flr(struct xe_device *xe)
> {
> 	const unsigned int flr_timeout = 3 * MICRO; /* specs recommend a 3s wait */
> 	struct xe_gt *gt = xe_root_mmio_gt(xe);
> 	int ret;
>
>-	if (xe_mmio_read32(gt, GU_CNTL_PROTECTED) & DRIVERINT_FLR_DIS) {
>-		drm_info_once(&xe->drm, "BIOS Disabled Driver-FLR\n");
>-		return;
>-	}
>-
> 	drm_dbg(&xe->drm, "Triggering Driver-FLR\n");
>
> 	/*
>@@ -447,6 +447,16 @@ static void xe_driver_flr(struct xe_device *xe)
> 	xe_mmio_write32(gt, GU_DEBUG, DRIVERFLR_STATUS);
> }
>
>+static void xe_driver_flr(struct xe_device *xe)
>+{
>+	if (xe_driver_flr_disabled(xe)) {
>+		drm_info_once(&xe->drm, "BIOS Disabled Driver-FLR\n");
>+		return;
>+	}
>+
>+	__xe_driver_flr(xe);
>+}
>+
> static void xe_driver_flr_fini(void *arg)
> {
> 	struct xe_device *xe = arg;
>@@ -798,6 +808,24 @@ void xe_device_remove(struct xe_device *xe)
>
> void xe_device_shutdown(struct xe_device *xe)
> {
>+	struct xe_gt *gt;
>+	u8 id;
>+
>+	drm_dbg(&xe->drm, "Shutting down device\n");
>+
>+	if (xe_driver_flr_disabled(xe)) {
>+		xe_display_pm_shutdown(xe);
>+
>+		xe_irq_suspend(xe);
>+
>+		for_each_gt(gt, xe, id)
>+			xe_gt_shutdown(gt);
>+
>+		xe_display_pm_shutdown_late(xe);
>+	} else {
>+		/* BOOM! */
>+		__xe_driver_flr(xe);

is this just so we don't read the register twice? Not really necessary,
is it? Otherwise let's please add an xe_assert() so we catch in CI cases
that this is eventually called in other paths that shouldn't.


Lucas De Marchi