1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * PowerPC ELF notes. 4 * 5 * Copyright 2019, IBM Corporation 6 */ 7 8#include <linux/elfnote.h> 9#include <asm/elfnote.h> 10 11/* 12 * Ultravisor-capable bit (PowerNV only). 13 * 14 * Bit 0 indicates that the powerpc kernel binary knows how to run in an 15 * ultravisor-enabled system. 16 * 17 * In an ultravisor-enabled system, some machine resources are now controlled 18 * by the ultravisor. If the kernel is not ultravisor-capable, but it ends up 19 * being run on a machine with ultravisor, the kernel will probably crash 20 * trying to access ultravisor resources. For instance, it may crash in early 21 * boot trying to set the partition table entry 0. 22 * 23 * In an ultravisor-enabled system, a bootloader could warn the user or prevent 24 * the kernel from being run if the PowerPC ultravisor capability doesn't exist 25 * or the Ultravisor-capable bit is not set. 26 */ 27#ifdef CONFIG_PPC_POWERNV 28#define PPCCAP_ULTRAVISOR_BIT (1 << 0) 29#else 30#define PPCCAP_ULTRAVISOR_BIT 0 31#endif 32 33/* 34 * Add the PowerPC Capabilities in the binary ELF note. It is a bitmap that 35 * can be used to advertise kernel capabilities to userland. 36 */ 37#define PPC_CAPABILITIES_BITMAP (PPCCAP_ULTRAVISOR_BIT) 38 39ELFNOTE(PowerPC, PPC_ELFNOTE_CAPABILITIES, 40 .long PPC_CAPABILITIES_BITMAP) 41