1 files changed, 360 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
new file mode 100644
index 000000000..0d3b22a74
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
@@ -0,0 +1,360 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#include <linux/types.h>
+
+#include "gt/intel_gt.h"
+#include "gt/intel_gt_print.h"
+#include "intel_gsc_fw.h"
+#include "intel_gsc_proxy.h"
+#include "intel_gsc_uc.h"
+#include "i915_drv.h"
+#include "i915_reg.h"
+
+static void gsc_work(struct work_struct *work)
+{
+	struct intel_gsc_uc *gsc = container_of(work, typeof(*gsc), work);
+	struct intel_gt *gt = gsc_uc_to_gt(gsc);
+	intel_wakeref_t wakeref;
+	u32 actions;
+	int ret;
+
+	wakeref = intel_runtime_pm_get(gt->uncore->rpm);
+
+	spin_lock_irq(gt->irq_lock);
+	actions = gsc->gsc_work_actions;
+	gsc->gsc_work_actions = 0;
+	spin_unlock_irq(gt->irq_lock);
+
+	if (actions & GSC_ACTION_FW_LOAD) {
+		ret = intel_gsc_uc_fw_upload(gsc);
+		if (!ret)
+			/* setup proxy on a new load */
+			actions |= GSC_ACTION_SW_PROXY;
+		else if (ret != -EEXIST)
+			goto out_put;
+
+		/*
+		 * The HuC auth can be done both before or after the proxy init;
+		 * if done after, a proxy request will be issued and must be
+		 * serviced before the authentication can complete.
+		 * Since this worker also handles proxy requests, we can't
+		 * perform an action that requires the proxy from within it and
+		 * then stall waiting for it, because we'd be blocking the
+		 * service path. Therefore, it is easier for us to load HuC
+		 * first and do proxy later. The GSC will ack the HuC auth and
+		 * then send the HuC proxy request as part of the proxy init
+		 * flow.
+		 * Note that we can only do the GSC auth if the GuC auth was
+		 * successful.
+		 */
+		if (intel_uc_uses_huc(&gt->uc) &&
+		    intel_huc_is_authenticated(&gt->uc.huc, INTEL_HUC_AUTH_BY_GUC))
+			intel_huc_auth(&gt->uc.huc, INTEL_HUC_AUTH_BY_GSC);
+	}
+
+	if (actions & GSC_ACTION_SW_PROXY) {
+		if (!intel_gsc_uc_fw_init_done(gsc)) {
+			gt_err(gt, "Proxy request received with GSC not loaded!\n");
+			goto out_put;
+		}
+
+		ret = intel_gsc_proxy_request_handler(gsc);
+		if (ret) {
+			if (actions & GSC_ACTION_FW_LOAD) {
+				/*
+				 * A proxy failure right after firmware load means the proxy-init
+				 * step has failed so mark GSC as not usable after this
+				 */
+				drm_err(&gt->i915->drm,
+					"GSC proxy handler failed to init\n");
+				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
+			}
+			goto out_put;
+		}
+
+		/* mark the GSC FW init as done the first time we run this */
+		if (actions & GSC_ACTION_FW_LOAD) {
+			/*
+			 * If there is a proxy establishment error, the GSC might still
+			 * complete the request handling cleanly, so we need to check the
+			 * status register to check if the proxy init was actually successful
+			 */
+			if (intel_gsc_uc_fw_proxy_init_done(gsc, false)) {
+				drm_dbg(&gt->i915->drm, "GSC Proxy initialized\n");
+				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_RUNNING);
+			} else {
+				drm_err(&gt->i915->drm,
+					"GSC status reports proxy init not complete\n");
+				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
+			}
+		}
+	}
+
+out_put:
+	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
+}
+
+static bool gsc_engine_supported(struct intel_gt *gt)
+{
+	intel_engine_mask_t mask;
+
+	/*
+	 * We reach here from i915_driver_early_probe for the primary GT before
+	 * its engine mask is set, so we use the device info engine mask for it.
+	 * For other GTs we expect the GT-specific mask to be set before we
+	 * call this function.
+	 */
+	GEM_BUG_ON(!gt_is_root(gt) && !gt->info.engine_mask);
+
+	if (gt_is_root(gt))
+		mask = INTEL_INFO(gt->i915)->platform_engine_mask;
+	else
+		mask = gt->info.engine_mask;
+
+	return __HAS_ENGINE(mask, GSC0);
+}
+
+void intel_gsc_uc_init_early(struct intel_gsc_uc *gsc)
+{
+	struct intel_gt *gt = gsc_uc_to_gt(gsc);
+
+	/*
+	 * GSC FW needs to be copied to a dedicated memory allocations for
+	 * loading (see gsc->local), so we don't need to GGTT map the FW image
+	 * itself into GGTT.
+	 */
+	intel_uc_fw_init_early(&gsc->fw, INTEL_UC_FW_TYPE_GSC, false);
+	INIT_WORK(&gsc->work, gsc_work);
+
+	/* we can arrive here from i915_driver_early_probe for primary
+	 * GT with it being not fully setup hence check device info's
+	 * engine mask
+	 */
+	if (!gsc_engine_supported(gt)) {
+		intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_NOT_SUPPORTED);
+		return;
+	}
+
+	gsc->wq = alloc_ordered_workqueue("i915_gsc", 0);
+	if (!gsc->wq) {
+		gt_err(gt, "failed to allocate WQ for GSC, disabling FW\n");
+		intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_NOT_SUPPORTED);
+	}
+}
+
+static int gsc_allocate_and_map_vma(struct intel_gsc_uc *gsc, u32 size)
+{
+	struct intel_gt *gt = gsc_uc_to_gt(gsc);
+	struct drm_i915_gem_object *obj;
+	struct i915_vma *vma;
+	void __iomem *vaddr;
+	int ret = 0;
+
+	/*
+	 * The GSC FW doesn't immediately suspend after becoming idle, so there
+	 * is a chance that it could still be awake after we successfully
+	 * return from the  pci suspend function, even if there are no pending
+	 * operations.
+	 * The FW might therefore try to access memory for its suspend operation
+	 * after the kernel has completed the HW suspend flow; this can cause
+	 * issues if the FW is mapped in normal RAM memory, as some of the
+	 * involved HW units might've already lost power.
+	 * The driver must therefore avoid this situation and the recommended
+	 * way to do so is to use stolen memory for the GSC memory allocation,
+	 * because stolen memory takes a different path in HW and it is
+	 * guaranteed to always work as long as the GPU itself is awake (which
+	 * it must be if the GSC is awake).
+	 */
+	obj = i915_gem_object_create_stolen(gt->i915, size);
+	if (IS_ERR(obj))
+		return PTR_ERR(obj);
+
+	vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
+	if (IS_ERR(vma)) {
+		ret = PTR_ERR(vma);
+		goto err;
+	}
+
+	vaddr = i915_vma_pin_iomap(vma);
+	i915_vma_unpin(vma);
+	if (IS_ERR(vaddr)) {
+		ret = PTR_ERR(vaddr);
+		goto err;
+	}
+
+	i915_vma_make_unshrinkable(vma);
+
+	gsc->local = vma;
+	gsc->local_vaddr = vaddr;
+
+	return 0;
+
+err:
+	i915_gem_object_put(obj);
+	return ret;
+}
+
+static void gsc_unmap_and_free_vma(struct intel_gsc_uc *gsc)
+{
+	struct i915_vma *vma = fetch_and_zero(&gsc->local);
+
+	if (!vma)
+		return;
+
+	gsc->local_vaddr = NULL;
+	i915_vma_unpin_iomap(vma);
+	i915_gem_object_put(vma->obj);
+}
+
+int intel_gsc_uc_init(struct intel_gsc_uc *gsc)
+{
+	static struct lock_class_key gsc_lock;
+	struct intel_gt *gt = gsc_uc_to_gt(gsc);
+	struct intel_engine_cs *engine = gt->engine[GSC0];
+	struct intel_context *ce;
+	int err;
+
+	err = intel_uc_fw_init(&gsc->fw);
+	if (err)
+		goto out;
+
+	err = gsc_allocate_and_map_vma(gsc, SZ_4M);
+	if (err)
+		goto out_fw;
+
+	ce = intel_engine_create_pinned_context(engine, engine->gt->vm, SZ_4K,
+						I915_GEM_HWS_GSC_ADDR,
+						&gsc_lock, "gsc_context");
+	if (IS_ERR(ce)) {
+		gt_err(gt, "failed to create GSC CS ctx for FW communication\n");
+		err =  PTR_ERR(ce);
+		goto out_vma;
+	}
+
+	gsc->ce = ce;
+
+	/* if we fail to init proxy we still want to load GSC for PM */
+	intel_gsc_proxy_init(gsc);
+
+	intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOADABLE);
+
+	return 0;
+
+out_vma:
+	gsc_unmap_and_free_vma(gsc);
+out_fw:
+	intel_uc_fw_fini(&gsc->fw);
+out:
+	gt_probe_error(gt, "GSC init failed %pe\n", ERR_PTR(err));
+	return err;
+}
+
+void intel_gsc_uc_fini(struct intel_gsc_uc *gsc)
+{
+	if (!intel_uc_fw_is_loadable(&gsc->fw))
+		return;
+
+	flush_work(&gsc->work);
+	if (gsc->wq) {
+		destroy_workqueue(gsc->wq);
+		gsc->wq = NULL;
+	}
+
+	intel_gsc_proxy_fini(gsc);
+
+	if (gsc->ce)
+		intel_engine_destroy_pinned_context(fetch_and_zero(&gsc->ce));
+
+	gsc_unmap_and_free_vma(gsc);
+
+	intel_uc_fw_fini(&gsc->fw);
+}
+
+void intel_gsc_uc_flush_work(struct intel_gsc_uc *gsc)
+{
+	if (!intel_uc_fw_is_loadable(&gsc->fw))
+		return;
+
+	flush_work(&gsc->work);
+}
+
+void intel_gsc_uc_resume(struct intel_gsc_uc *gsc)
+{
+	if (!intel_uc_fw_is_loadable(&gsc->fw))
+		return;
+
+	/*
+	 * we only want to start the GSC worker from here in the actual resume
+	 * flow and not during driver load. This is because GSC load is slow and
+	 * therefore we want to make sure that the default state init completes
+	 * first to not slow down the init thread. A separate call to
+	 * intel_gsc_uc_load_start will ensure that the GSC is loaded during
+	 * driver load.
+	 */
+	if (!gsc_uc_to_gt(gsc)->engine[GSC0]->default_state)
+		return;
+
+	intel_gsc_uc_load_start(gsc);
+}
+
+void intel_gsc_uc_load_start(struct intel_gsc_uc *gsc)
+{
+	struct intel_gt *gt = gsc_uc_to_gt(gsc);
+
+	if (!intel_uc_fw_is_loadable(&gsc->fw))
+		return;
+
+	if (intel_gsc_uc_fw_init_done(gsc))
+		return;
+
+	spin_lock_irq(gt->irq_lock);
+	gsc->gsc_work_actions |= GSC_ACTION_FW_LOAD;
+	spin_unlock_irq(gt->irq_lock);
+
+	queue_work(gsc->wq, &gsc->work);
+}
+
+void intel_gsc_uc_load_status(struct intel_gsc_uc *gsc, struct drm_printer *p)
+{
+	struct intel_gt *gt = gsc_uc_to_gt(gsc);
+	struct intel_uncore *uncore = gt->uncore;
+	intel_wakeref_t wakeref;
+
+	if (!intel_gsc_uc_is_supported(gsc)) {
+		drm_printf(p, "GSC not supported\n");
+		return;
+	}
+
+	if (!intel_gsc_uc_is_wanted(gsc)) {
+		drm_printf(p, "GSC disabled\n");
+		return;
+	}
+
+	drm_printf(p, "GSC firmware: %s\n", gsc->fw.file_selected.path);
+	if (gsc->fw.file_selected.path != gsc->fw.file_wanted.path)
+		drm_printf(p, "GSC firmware wanted: %s\n", gsc->fw.file_wanted.path);
+	drm_printf(p, "\tstatus: %s\n", intel_uc_fw_status_repr(gsc->fw.status));
+
+	drm_printf(p, "Release: %u.%u.%u.%u\n",
+		   gsc->release.major, gsc->release.minor,
+		   gsc->release.patch, gsc->release.build);
+
+	drm_printf(p, "Compatibility Version: %u.%u [min expected %u.%u]\n",
+		   gsc->fw.file_selected.ver.major, gsc->fw.file_selected.ver.minor,
+		   gsc->fw.file_wanted.ver.major, gsc->fw.file_wanted.ver.minor);
+
+	drm_printf(p, "SVN: %u\n", gsc->security_version);
+
+	with_intel_runtime_pm(uncore->rpm, wakeref) {
+		u32 i;
+
+		for (i = 1; i <= 6; i++) {
+			u32 status = intel_uncore_read(uncore,
+						       HECI_FWSTS(MTL_GSC_HECI1_BASE, i));
+			drm_printf(p, "HECI1 FWSTST%u = 0x%08x\n", i, status);
+		}
+	}
+}