+/*
+ * This function resets the command buffer if the IOMMU stopped fetching
+ * commands from it.
+ */
+void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu)
+{
+ iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
+
+ writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
+ writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
+
+ iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
+}
+