From aaddd3eacaeaef3503035750b3f21ac2bfe97cbf Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 24 Jun 2008 11:32:21 +1000 Subject: powerpc: Move code patching code into arch/powerpc/lib/code-patching.c We currently have a few routines for patching code in asm/system.h, because they didn't fit anywhere else. I'd like to clean them up a little and add some more, so first move them into a dedicated C file - they don't need to be inlined. While we're moving the code, drop create_function_call(), it's intended caller never got merged and will be replaced in future with something different. Signed-off-by: Michael Ellerman Acked-by: Kumar Gala Signed-off-by: Paul Mackerras --- include/asm-powerpc/code-patching.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 include/asm-powerpc/code-patching.h (limited to 'include/asm-powerpc/code-patching.h') diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h new file mode 100644 index 000000000000..0b91fdf944db --- /dev/null +++ b/include/asm-powerpc/code-patching.h @@ -0,0 +1,25 @@ +#ifndef _ASM_POWERPC_CODE_PATCHING_H +#define _ASM_POWERPC_CODE_PATCHING_H + +/* + * Copyright 2008, Michael Ellerman, 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. + */ + +/* Flags for create_branch: + * "b" == create_branch(addr, target, 0); + * "ba" == create_branch(addr, target, BRANCH_ABSOLUTE); + * "bl" == create_branch(addr, target, BRANCH_SET_LINK); + * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK); + */ +#define BRANCH_SET_LINK 0x1 +#define BRANCH_ABSOLUTE 0x2 + +extern void create_branch(unsigned long addr, unsigned long target, int flags); +extern void create_instruction(unsigned long addr, unsigned int instr); + +#endif /* _ASM_POWERPC_CODE_PATCHING_H */ -- cgit v1.2.3 From e7a57273c6407bb6903fbaddec8c2119bf318617 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 24 Jun 2008 11:32:22 +1000 Subject: powerpc: Allow create_branch() to return errors Currently create_branch() creates a branch instruction for you, and patches it into the call site. In some circumstances it would be nice to be able to create the instruction and patch it later, and also some code might want to check for errors in the branch creation before doing the patching. A future commit will change create_branch() to check for errors. For callers that don't care, replace create_branch() with patch_branch(), which just creates the branch and patches it directly. While we're touching all the callers, change to using unsigned int *, as this seems to match usage better. That allows (and requires) us to remove the volatile in the definition of vector in powermac/smp.c and mpc86xx_smp.c, that's correct because now that we're passing vector as an unsigned int * the compiler knows that it's value might change across the patch_branch() call. Signed-off-by: Michael Ellerman Acked-by: Kumar Gala Acked-by: Jon Loeliger Signed-off-by: Paul Mackerras --- include/asm-powerpc/code-patching.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include/asm-powerpc/code-patching.h') diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h index 0b91fdf944db..fdb187cbc40d 100644 --- a/include/asm-powerpc/code-patching.h +++ b/include/asm-powerpc/code-patching.h @@ -19,7 +19,9 @@ #define BRANCH_SET_LINK 0x1 #define BRANCH_ABSOLUTE 0x2 -extern void create_branch(unsigned long addr, unsigned long target, int flags); -extern void create_instruction(unsigned long addr, unsigned int instr); +unsigned int create_branch(const unsigned int *addr, + unsigned long target, int flags); +void patch_branch(unsigned int *addr, unsigned long target, int flags); +void patch_instruction(unsigned int *addr, unsigned int instr); #endif /* _ASM_POWERPC_CODE_PATCHING_H */ -- cgit v1.2.3 From 07630a37beefe8e4401c602f04e3e5bcbba50b31 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 24 Jun 2008 11:32:28 +1000 Subject: powerpc: Add ppc_function_entry() which gets the entry point for a function Because function pointers point to different things on 32-bit vs 64-bit, add a macro that deals with dereferencing the OPD on 64-bit. The soon to be merged ftrace wants this, as well as other code I am working on. Signed-off-by: Michael Ellerman Acked-by: Kumar Gala Signed-off-by: Paul Mackerras --- include/asm-powerpc/code-patching.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'include/asm-powerpc/code-patching.h') diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h index fdb187cbc40d..a45a7ff78725 100644 --- a/include/asm-powerpc/code-patching.h +++ b/include/asm-powerpc/code-patching.h @@ -10,6 +10,8 @@ * 2 of the License, or (at your option) any later version. */ +#include + /* Flags for create_branch: * "b" == create_branch(addr, target, 0); * "ba" == create_branch(addr, target, BRANCH_ABSOLUTE); @@ -24,4 +26,18 @@ unsigned int create_branch(const unsigned int *addr, void patch_branch(unsigned int *addr, unsigned long target, int flags); void patch_instruction(unsigned int *addr, unsigned int instr); +static inline unsigned long ppc_function_entry(void *func) +{ +#ifdef CONFIG_PPC64 + /* + * On PPC64 the function pointer actually points to the function's + * descriptor. The first entry in the descriptor is the address + * of the function text. + */ + return ((func_descr_t *)func)->entry; +#else + return (unsigned long)func; +#endif +} + #endif /* _ASM_POWERPC_CODE_PATCHING_H */ -- cgit v1.2.3 From 411781a290b0d0a31fd73826b3ee110f1e3cc3b6 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 24 Jun 2008 11:32:29 +1000 Subject: powerpc: Add new code patching routines This commit adds some new routines for patching code, which will be used in a following commit. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras --- include/asm-powerpc/code-patching.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/asm-powerpc/code-patching.h') diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h index a45a7ff78725..40ad46b1dd9d 100644 --- a/include/asm-powerpc/code-patching.h +++ b/include/asm-powerpc/code-patching.h @@ -23,9 +23,17 @@ unsigned int create_branch(const unsigned int *addr, unsigned long target, int flags); +unsigned int create_cond_branch(const unsigned int *addr, + unsigned long target, int flags); void patch_branch(unsigned int *addr, unsigned long target, int flags); void patch_instruction(unsigned int *addr, unsigned int instr); +int instr_is_relative_branch(unsigned int instr); +int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr); +unsigned long branch_target(const unsigned int *instr); +unsigned int translate_branch(const unsigned int *dest, + const unsigned int *src); + static inline unsigned long ppc_function_entry(void *func) { #ifdef CONFIG_PPC64 -- cgit v1.2.3 From b7bcda631e87eb3466d0baa9885650ba7d7ed89d Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 24 Jun 2008 11:32:35 +1000 Subject: powerpc: Add PPC_NOP_INSTR, a hash define for the preferred nop instruction A bunch of code has hard-coded the value for a "nop" instruction, it would be nice to have a #define for it. Signed-off-by: Michael Ellerman Acked-by: Kumar Gala Signed-off-by: Paul Mackerras --- include/asm-powerpc/code-patching.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/asm-powerpc/code-patching.h') diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h index 40ad46b1dd9d..ef3a5d156dba 100644 --- a/include/asm-powerpc/code-patching.h +++ b/include/asm-powerpc/code-patching.h @@ -12,6 +12,8 @@ #include +#define PPC_NOP_INSTR 0x60000000 + /* Flags for create_branch: * "b" == create_branch(addr, target, 0); * "ba" == create_branch(addr, target, BRANCH_ABSOLUTE); -- cgit v1.2.3 From 2d1b2027626d5151fff8ef7c06ca8e7876a1a510 Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Wed, 2 Jul 2008 01:16:40 +1000 Subject: powerpc: Fixup lwsync at runtime To allow for a single kernel image on e500 v1/v2/mc we need to fixup lwsync at runtime. On e500v1/v2 lwsync causes an illop so we need to patch up the code. We default to 'sync' since that is always safe and if the cpu is capable we will replace 'sync' with 'lwsync'. We introduce CPU_FTR_LWSYNC as a way to determine at runtime if this is needed. This flag could be moved elsewhere since we dont really use it for the normal CPU_FTR purpose. Finally we only store the relative offset in the fixup section to keep it as small as possible rather than using a full fixup_entry. Signed-off-by: Kumar Gala Signed-off-by: Paul Mackerras --- include/asm-powerpc/code-patching.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/asm-powerpc/code-patching.h') diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h index ef3a5d156dba..107d9b915e33 100644 --- a/include/asm-powerpc/code-patching.h +++ b/include/asm-powerpc/code-patching.h @@ -12,7 +12,8 @@ #include -#define PPC_NOP_INSTR 0x60000000 +#define PPC_NOP_INSTR 0x60000000 +#define PPC_LWSYNC_INSTR 0x7c2004ac /* Flags for create_branch: * "b" == create_branch(addr, target, 0); -- cgit v1.2.3