1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/display/ext/i915_irq.c b/drivers/gpu/drm/xe/display/ext/i915_irq.c
new file mode 100644
index 000000000000..bee191a4a97d
--- /dev/null
+++ b/drivers/gpu/drm/xe/display/ext/i915_irq.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#include "i915_drv.h"
+#include "i915_irq.h"
+#include "i915_reg.h"
+#include "intel_uncore.h"
+
+void gen3_irq_reset(struct intel_uncore *uncore, i915_reg_t imr,
+		    i915_reg_t iir, i915_reg_t ier)
+{
+	intel_uncore_write(uncore, imr, 0xffffffff);
+	intel_uncore_posting_read(uncore, imr);
+
+	intel_uncore_write(uncore, ier, 0);
+
+	/* IIR can theoretically queue up two events. Be paranoid. */
+	intel_uncore_write(uncore, iir, 0xffffffff);
+	intel_uncore_posting_read(uncore, iir);
+	intel_uncore_write(uncore, iir, 0xffffffff);
+	intel_uncore_posting_read(uncore, iir);
+}
+
+/*
+ * We should clear IMR at preinstall/uninstall, and just check at postinstall.
+ */
+void gen3_assert_iir_is_zero(struct intel_uncore *uncore, i915_reg_t reg)
+{
+	struct xe_device *xe = container_of(uncore, struct xe_device, uncore);
+	u32 val = intel_uncore_read(uncore, reg);
+
+	if (val == 0)
+		return;
+
+	drm_WARN(&xe->drm, 1,
+		 "Interrupt register 0x%x is not zero: 0x%08x\n",
+		 i915_mmio_reg_offset(reg), val);
+	intel_uncore_write(uncore, reg, 0xffffffff);
+	intel_uncore_posting_read(uncore, reg);
+	intel_uncore_write(uncore, reg, 0xffffffff);
+	intel_uncore_posting_read(uncore, reg);
+}
+
+void gen3_irq_init(struct intel_uncore *uncore,
+		   i915_reg_t imr, u32 imr_val,
+		   i915_reg_t ier, u32 ier_val,
+		   i915_reg_t iir)
+{
+	gen3_assert_iir_is_zero(uncore, iir);
+
+	intel_uncore_write(uncore, ier, ier_val);
+	intel_uncore_write(uncore, imr, imr_val);
+	intel_uncore_posting_read(uncore, imr);
+}
+
+bool intel_irqs_enabled(struct xe_device *xe)
+{
+	/*
+	 * XXX: i915 has a racy handling of the irq.enabled, since it doesn't
+	 * lock its transitions. Because of that, the irq.enabled sometimes
+	 * is not read with the irq.lock in place.
+	 * However, the most critical cases like vblank and page flips are
+	 * properly using the locks.
+	 * We cannot take the lock in here or run any kind of assert because
+	 * of i915 inconsistency.
+	 * But at this point the xe irq is better protected against races,
+	 * although the full solution would be protecting the i915 side.
+	 */
+	return xe->irq.enabled;
+}
+
+void intel_synchronize_irq(struct xe_device *xe)
+{
+	synchronize_irq(to_pci_dev(xe->drm.dev)->irq);
+}