system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-09-19 18:46:35 +00:00
Code Issues Packages Projects Releases Wiki Activity

powerpc: Add module autoloading based on CPU features

Browse source 
This patch provides the necessary infrastructure to allow drivers
to be automatically loaded via udev. It implements the minimum
required to be able to use module_cpu_feature_match() to trigger
the GENERIC_CPU_AUTOPROBE mechanisms.

The features exposed are a mirror of the cpu_user_features
(converted to an offset from a mask). This decision was made to
ensure that the behavior between features for module loading and
userspace are consistent.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
[mpe: Only define the bits we currently need]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Alastair D'Silva 2016-07-19 14:03:52 +10:00 committed by Michael Ellerman
parent 802a345183
commit 4a1202765d
2 changed files with 41 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
arch/powerpc/Kconfig
View file

@ -165,6 +165,7 @@ config PPC
select ARCH_HAS_UBSAN_SANITIZE_ALL
select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
select HAVE_LIVEPATCH if HAVE_DYNAMIC_FTRACE_WITH_REGS
select GENERIC_CPU_AUTOPROBE
config GENERIC_CSUM
def_bool CPU_LITTLE_ENDIAN

40
arch/powerpc/include/asm/cpufeature.h Normal file
View file

@ -0,0 +1,40 @@
/*
* CPU feature definitions for module loading, used by
* module_cpu_feature_match(), see asm/cputable.h for powerpc CPU features.
*
* Copyright 2016 Alastair D'Silva, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef __ASM_POWERPC_CPUFEATURE_H
#define __ASM_POWERPC_CPUFEATURE_H
#include <asm/cputable.h>
/* Keep these in step with powerpc/include/asm/cputable.h */
#define MAX_CPU_FEATURES (2 * 32)
/*
* Currently we don't have a need for any of the feature bits defined in
* cpu_user_features. When we do, they should be defined such as:
*
* #define PPC_MODULE_FEATURE_32 (ilog2(PPC_FEATURE_32))
*/
#define PPC_MODULE_FEATURE_VEC_CRYPTO (32 + ilog2(PPC_FEATURE2_VEC_CRYPTO))
#define cpu_feature(x) (x)
static inline bool cpu_have_feature(unsigned int num)
{
if (num < 32)
return !!(cur_cpu_spec->cpu_user_features & 1UL << num);
else
return !!(cur_cpu_spec->cpu_user_features2 & 1UL << (num - 32));
}
#endif /* __ASM_POWERPC_CPUFEATURE_H */