linux-stable.git/arch/powerpc/include/asm/code-patching.h, branch v5.12.2

powerpc/64s: Use symbolic macros for function entry encoding

2021-03-09T20:58:04+00:00

In ppc_function_entry() we look for a specific set of instructions by
masking the instructions and comparing with a known value. Currently
those known values are just literal hex values, and we recently
discovered one of them was wrong.

Instead construct the values using the existing constants we have for
defining various fields of instructions.

Suggested-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Acked-by: Naveen N. Rao 
Link: https://lore.kernel.org/r/20210309071544.515303-1-mpe@ellerman.id.au

powerpc/64s: Fix instruction encoding for lis in ppc_function_entry()

2021-03-09T11:13:26+00:00

'lis r2,N' is 'addis r2,0,N' and the instruction encoding in the macro
LIS_R2 is incorrect (it currently maps to 'addis r0,r2,N'). Fix the
same.

Fixes: c71b7eff426f ("powerpc: Add ABIv2 support to ppc_function_entry")
Cc: stable@vger.kernel.org # v3.16+
Reported-by: Jiri Olsa 
Signed-off-by: Naveen N. Rao 
Acked-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210304020411.16796-1-naveen.n.rao@linux.vnet.ibm.com

powerpc: Use a datatype for instructions

2020-05-18T14:10:37+00:00

Currently unsigned ints are used to represent instructions on powerpc.
This has worked well as instructions have always been 4 byte words.

However, ISA v3.1 introduces some changes to instructions that mean
this scheme will no longer work as well. This change is Prefixed
Instructions. A prefixed instruction is made up of a word prefix
followed by a word suffix to make an 8 byte double word instruction.
No matter the endianness of the system the prefix always comes first.
Prefixed instructions are only planned for powerpc64.

Introduce a ppc_inst type to represent both prefixed and word
instructions on powerpc64 while keeping it possible to exclusively
have word instructions on powerpc32.

Signed-off-by: Jordan Niethe 
[mpe: Fix compile error in emulate_spe()]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com

powerpc: Use a macro for creating instructions from u32s

2020-05-18T14:10:36+00:00

In preparation for instructions having a more complex data type start
using a macro, ppc_inst(), for making an instruction out of a u32.  A
macro is used so that instructions can be used as initializer elements.
Currently this does nothing, but it will allow for creating a data type
that can represent prefixed instructions.

Signed-off-by: Jordan Niethe 
[mpe: Change include guard to _ASM_POWERPC_INST_H]
Signed-off-by: Michael Ellerman 
Reviewed-by: Alistair Popple 
Link: https://lore.kernel.org/r/20200506034050.24806-7-jniethe5@gmail.com

powerpc: Change calling convention for create_branch() et. al.

2020-05-18T14:10:36+00:00

create_branch(), create_cond_branch() and translate_branch() return the
instruction that they create, or return 0 to signal an error. Separate
these concerns in preparation for an instruction type that is not just
an unsigned int.  Fill the created instruction to a pointer passed as
the first parameter to the function and use a non-zero return value to
signify an error.

Signed-off-by: Jordan Niethe 
Signed-off-by: Michael Ellerman 
Reviewed-by: Alistair Popple 
Link: https://lore.kernel.org/r/20200506034050.24806-6-jniethe5@gmail.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

powerpc: add modify_instruction() and modify_instruction_site()

2018-12-19T07:56:32+00:00

Add two helpers to avoid hardcoding of instructions modifications.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc: simplify patch_instruction_site() and patch_branch_site()

2018-12-19T07:56:32+00:00

Using patch_site_addr() helper, patch_instruction_site() and
patch_branch_site() can be simplified and inlined.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc/code-patching: Add a helper to get the address of a patch_site

2018-10-26T10:58:58+00:00

This patch adds a helper to get the address of a patch_site.

Signed-off-by: Christophe Leroy 
[mpe: Call it "patch site" addr]
Signed-off-by: Michael Ellerman

powerpc/asm: Add a patch_site macro & helpers for patching instructions

2018-08-07T14:32:25+00:00

Add a macro and some helper C functions for patching single asm
instructions.

The gas macro means we can do something like:

  1:	nop
  	patch_site 1b, patch__foo

Which is less visually distracting than defining a GLOBAL symbol at 1,
and also doesn't pollute the symbol table which can confuse eg. perf.

These are obviously similar to our existing feature sections, but are
not automatically patched based on CPU/MMU features, rather they are
designed to be manually patched by C code at some arbitrary point.

Signed-off-by: Michael Ellerman