mirror of
https://github.com/brain-hackers/linux-brain.git
synced 2024-06-09 23:36:23 +09:00
70ed86f4de
Add the PowerPC name and the PPC_ELFNOTE_CAPABILITIES type in the kernel binary ELF note. This type is a bitmap that can be used to advertise kernel capabilities to userland. This patch also defines PPCCAP_ULTRAVISOR_BIT as being the bit zero. Suggested-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com> [ maxiwell: Define the 'PowerPC' type in the elfnote.h ] Signed-off-by: Maxiwell S. Garcia <maxiwell@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190829155021.2915-2-maxiwell@linux.ibm.com
41 lines
1.2 KiB
ArmAsm
41 lines
1.2 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* PowerPC ELF notes.
|
|
*
|
|
* Copyright 2019, IBM Corporation
|
|
*/
|
|
|
|
#include <linux/elfnote.h>
|
|
#include <asm/elfnote.h>
|
|
|
|
/*
|
|
* Ultravisor-capable bit (PowerNV only).
|
|
*
|
|
* Bit 0 indicates that the powerpc kernel binary knows how to run in an
|
|
* ultravisor-enabled system.
|
|
*
|
|
* In an ultravisor-enabled system, some machine resources are now controlled
|
|
* by the ultravisor. If the kernel is not ultravisor-capable, but it ends up
|
|
* being run on a machine with ultravisor, the kernel will probably crash
|
|
* trying to access ultravisor resources. For instance, it may crash in early
|
|
* boot trying to set the partition table entry 0.
|
|
*
|
|
* In an ultravisor-enabled system, a bootloader could warn the user or prevent
|
|
* the kernel from being run if the PowerPC ultravisor capability doesn't exist
|
|
* or the Ultravisor-capable bit is not set.
|
|
*/
|
|
#ifdef CONFIG_PPC_POWERNV
|
|
#define PPCCAP_ULTRAVISOR_BIT (1 << 0)
|
|
#else
|
|
#define PPCCAP_ULTRAVISOR_BIT 0
|
|
#endif
|
|
|
|
/*
|
|
* Add the PowerPC Capabilities in the binary ELF note. It is a bitmap that
|
|
* can be used to advertise kernel capabilities to userland.
|
|
*/
|
|
#define PPC_CAPABILITIES_BITMAP (PPCCAP_ULTRAVISOR_BIT)
|
|
|
|
ELFNOTE(PowerPC, PPC_ELFNOTE_CAPABILITIES,
|
|
.long PPC_CAPABILITIES_BITMAP)
|