--- /dev/null
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#include "gt/intel_gt.h"
+#include "gt/intel_hwconfig.h"
+#include "i915_drv.h"
+#include "i915_memcpy.h"
+
+/*
+ * GuC has a blob containing hardware configuration information (HWConfig).
+ * This is formatted as a simple and flexible KLV (Key/Length/Value) table.
+ *
+ * For example, a minimal version could be:
+ * enum device_attr {
+ * ATTR_SOME_VALUE = 0,
+ * ATTR_SOME_MASK = 1,
+ * };
+ *
+ * static const u32 hwconfig[] = {
+ * ATTR_SOME_VALUE,
+ * 1, // Value Length in DWords
+ * 8, // Value
+ *
+ * ATTR_SOME_MASK,
+ * 3,
+ * 0x00FFFFFFFF, 0xFFFFFFFF, 0xFF000000,
+ * };
+ *
+ * The attribute ids are defined in a hardware spec.
+ */
+
+static int __guc_action_get_hwconfig(struct intel_guc *guc,
+ u32 ggtt_offset, u32 ggtt_size)
+{
+ u32 action[] = {
+ INTEL_GUC_ACTION_GET_HWCONFIG,
+ lower_32_bits(ggtt_offset),
+ upper_32_bits(ggtt_offset),
+ ggtt_size,
+ };
+ int ret;
+
+ ret = intel_guc_send_mmio(guc, action, ARRAY_SIZE(action), NULL, 0);
+ if (ret == -ENXIO)
+ return -ENOENT;
+
+ return ret;
+}
+
+static int guc_hwconfig_discover_size(struct intel_guc *guc, struct intel_hwconfig *hwconfig)
+{
+ int ret;
+
+ /*
+ * Sending a query with zero offset and size will return the
+ * size of the blob.
+ */
+ ret = __guc_action_get_hwconfig(guc, 0, 0);
+ if (ret < 0)
+ return ret;
+
+ if (ret == 0)
+ return -EINVAL;
+
+ hwconfig->size = ret;
+ return 0;
+}
+
+static int guc_hwconfig_fill_buffer(struct intel_guc *guc, struct intel_hwconfig *hwconfig)
+{
+ struct i915_vma *vma;
+ u32 ggtt_offset;
+ void *vaddr;
+ int ret;
+
+ GEM_BUG_ON(!hwconfig->size);
+
+ ret = intel_guc_allocate_and_map_vma(guc, hwconfig->size, &vma, &vaddr);
+ if (ret)
+ return ret;
+
+ ggtt_offset = intel_guc_ggtt_offset(guc, vma);
+
+ ret = __guc_action_get_hwconfig(guc, ggtt_offset, hwconfig->size);
+ if (ret >= 0)
+ memcpy(hwconfig->ptr, vaddr, hwconfig->size);
+
+ i915_vma_unpin_and_release(&vma, I915_VMA_RELEASE_MAP);
+
+ return ret;
+}
+
+static bool has_table(struct drm_i915_private *i915)
+{
+ if (IS_ALDERLAKE_P(i915))
+ return true;
+
+ return false;
+}
+
+/**
+ * intel_guc_hwconfig_init - Initialize the HWConfig
+ *
+ * Retrieve the HWConfig table from the GuC and save it locally.
+ * It can then be queried on demand by other users later on.
+ */
+static int guc_hwconfig_init(struct intel_gt *gt)
+{
+ struct intel_hwconfig *hwconfig = >->info.hwconfig;
+ struct intel_guc *guc = >->uc.guc;
+ int ret;
+
+ if (!has_table(gt->i915))
+ return 0;
+
+ ret = guc_hwconfig_discover_size(guc, hwconfig);
+ if (ret)
+ return ret;
+
+ hwconfig->ptr = kmalloc(hwconfig->size, GFP_KERNEL);
+ if (!hwconfig->ptr) {
+ hwconfig->size = 0;
+ return -ENOMEM;
+ }
+
+ ret = guc_hwconfig_fill_buffer(guc, hwconfig);
+ if (ret < 0) {
+ intel_gt_fini_hwconfig(gt);
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * intel_gt_init_hwconfig - Initialize the HWConfig if available
+ *
+ * Retrieve the HWConfig table if available on the current platform.
+ */
+int intel_gt_init_hwconfig(struct intel_gt *gt)
+{
+ if (!intel_uc_uses_guc(>->uc))
+ return 0;
+
+ return guc_hwconfig_init(gt);
+}
+
+/**
+ * intel_gt_fini_hwconfig - Finalize the HWConfig
+ *
+ * Free up the memory allocation holding the table.
+ */
+void intel_gt_fini_hwconfig(struct intel_gt *gt)
+{
+ struct intel_hwconfig *hwconfig = >->info.hwconfig;
+
+ kfree(hwconfig->ptr);
+ hwconfig->size = 0;
+ hwconfig->ptr = NULL;
+}