+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Defines APIs that allow an OS to interact with UEFI firmware to query
+ * information about the boot hart ID.
+ *
+ * Copyright (c) 2022, Ventana Micro Systems Inc
+ */
+
+#define LOG_CATEGORY LOGC_EFI
+#include <common.h>
+#include <efi_loader.h>
+#include <efi_variable.h>
+#include <log.h>
+#include <asm/global_data.h>
+#include <efi_riscv.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const efi_guid_t efi_guid_riscv_boot_protocol = RISCV_EFI_BOOT_PROTOCOL_GUID;
+
+/**
+ * efi_riscv_get_boot_hartid() - return boot hart ID
+ * @this: RISCV_EFI_BOOT_PROTOCOL instance
+ * @boot_hartid: caller allocated memory to return boot hart id
+ * Return: status code
+ */
+static efi_status_t EFIAPI
+efi_riscv_get_boot_hartid(struct riscv_efi_boot_protocol *this,
+ efi_uintn_t *boot_hartid)
+{
+ EFI_ENTRY("%p, %p", this, boot_hartid);
+
+ if (this != &riscv_efi_boot_prot || !boot_hartid)
+ return EFI_INVALID_PARAMETER;
+
+ *boot_hartid = gd->arch.boot_hart;
+
+ return EFI_EXIT(EFI_SUCCESS);
+}
+
+struct riscv_efi_boot_protocol riscv_efi_boot_prot = {
+ .revision = RISCV_EFI_BOOT_PROTOCOL_REVISION,
+ .get_boot_hartid = efi_riscv_get_boot_hartid
+};
+
+/**
+ * efi_riscv_register() - register RISCV_EFI_BOOT_PROTOCOL
+ *
+ * Return: status code
+ */
+efi_status_t efi_riscv_register(void)
+{
+ efi_status_t ret = EFI_SUCCESS;
+
+ ret = efi_add_protocol(efi_root, &efi_guid_riscv_boot_protocol,
+ (void *)&riscv_efi_boot_prot);
+ if (ret != EFI_SUCCESS)
+ log_err("Cannot install RISCV_EFI_BOOT_PROTOCOL\n");
+ return ret;
+}