xref: /kernel/linux/linux-6.6/arch/powerpc/include/asm/feature-fixups.h (revision 62306a36)

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef __ASM_POWERPC_FEATURE_FIXUPS_H
#define __ASM_POWERPC_FEATURE_FIXUPS_H

#include <asm/asm-const.h>

/*
 */

/*
 * Feature section common macros
 *
 * Note that the entries now contain offsets between the table entry
 * and the code rather than absolute code pointers in order to be
 * useable with the vdso shared library. There is also an assumption
 * that values will be negative, that is, the fixup table has to be
 * located after the code it fixes up.
 */
#if defined(CONFIG_PPC64) && !defined(__powerpc64__)
/* 64 bits kernel, 32 bits code (ie. vdso32) */
#define FTR_ENTRY_LONG		.8byte
#define FTR_ENTRY_OFFSET	.long 0xffffffff; .long
#elif defined(CONFIG_PPC64)
#define FTR_ENTRY_LONG		.8byte
#define FTR_ENTRY_OFFSET	.8byte
#else
#define FTR_ENTRY_LONG		.long
#define FTR_ENTRY_OFFSET	.long
#endif

#define START_FTR_SECTION(label)	label##1:

#define FTR_SECTION_ELSE_NESTED(label)			\
label##2:						\
	.pushsection __ftr_alt_##label,"a";		\
	.align 2;					\
label##3:


#ifndef CONFIG_CC_IS_CLANG
#define CHECK_ALT_SIZE(else_size, body_size)			\
	.ifgt (else_size) - (body_size);			\
	.error "Feature section else case larger than body";	\
	.endif;
#else
/*
 * If we use the ifgt syntax above, clang's assembler complains about the
 * expression being non-absolute when the code appears in an inline assembly
 * statement.
 * As a workaround use an .org directive that has no effect if the else case
 * instructions are smaller than the body, but fails otherwise.
 */
#define CHECK_ALT_SIZE(else_size, body_size)			\
	.org . + ((else_size) > (body_size));
#endif

#define MAKE_FTR_SECTION_ENTRY(msk, val, label, sect)		\
label##4:							\
	.popsection;						\
	.pushsection sect,"a";					\
	.align 3;						\
label##5:							\
	FTR_ENTRY_LONG msk;					\
	FTR_ENTRY_LONG val;					\
	FTR_ENTRY_OFFSET label##1b-label##5b;			\
	FTR_ENTRY_OFFSET label##2b-label##5b;			\
	FTR_ENTRY_OFFSET label##3b-label##5b;			\
	FTR_ENTRY_OFFSET label##4b-label##5b;			\
	CHECK_ALT_SIZE((label##4b-label##3b), (label##2b-label##1b)); \
	.popsection;


/* CPU feature dependent sections */
#define BEGIN_FTR_SECTION_NESTED(label)	START_FTR_SECTION(label)
#define BEGIN_FTR_SECTION		START_FTR_SECTION(97)

#define END_FTR_SECTION_NESTED(msk, val, label) 		\
	FTR_SECTION_ELSE_NESTED(label)				\
	MAKE_FTR_SECTION_ENTRY(msk, val, label, __ftr_fixup)

#define END_FTR_SECTION(msk, val)		\
	END_FTR_SECTION_NESTED(msk, val, 97)

#define END_FTR_SECTION_NESTED_IFSET(msk, label)	\
	END_FTR_SECTION_NESTED((msk), (msk), label)

#define END_FTR_SECTION_IFSET(msk)	END_FTR_SECTION((msk), (msk))
#define END_FTR_SECTION_IFCLR(msk)	END_FTR_SECTION((msk), 0)

/* CPU feature sections with alternatives, use BEGIN_FTR_SECTION to start */
#define FTR_SECTION_ELSE	FTR_SECTION_ELSE_NESTED(97)
#define ALT_FTR_SECTION_END_NESTED(msk, val, label)	\
	MAKE_FTR_SECTION_ENTRY(msk, val, label, __ftr_fixup)
#define ALT_FTR_SECTION_END_NESTED_IFSET(msk, label)	\
	ALT_FTR_SECTION_END_NESTED(msk, msk, label)
#define ALT_FTR_SECTION_END_NESTED_IFCLR(msk, label)	\
	ALT_FTR_SECTION_END_NESTED(msk, 0, label)
#define ALT_FTR_SECTION_END(msk, val)	\
	ALT_FTR_SECTION_END_NESTED(msk, val, 97)
#define ALT_FTR_SECTION_END_IFSET(msk)	\
	ALT_FTR_SECTION_END_NESTED_IFSET(msk, 97)
#define ALT_FTR_SECTION_END_IFCLR(msk)	\
	ALT_FTR_SECTION_END_NESTED_IFCLR(msk, 97)

/* MMU feature dependent sections */
#define BEGIN_MMU_FTR_SECTION_NESTED(label)	START_FTR_SECTION(label)
#define BEGIN_MMU_FTR_SECTION			START_FTR_SECTION(97)

#define END_MMU_FTR_SECTION_NESTED(msk, val, label) 		\
	FTR_SECTION_ELSE_NESTED(label)				\
	MAKE_FTR_SECTION_ENTRY(msk, val, label, __mmu_ftr_fixup)

#define END_MMU_FTR_SECTION(msk, val)		\
	END_MMU_FTR_SECTION_NESTED(msk, val, 97)

#define END_MMU_FTR_SECTION_NESTED_IFSET(msk, label)	\
	END_MMU_FTR_SECTION_NESTED((msk), (msk), label)

#define END_MMU_FTR_SECTION_NESTED_IFCLR(msk, label)	\
	END_MMU_FTR_SECTION_NESTED((msk), 0, label)

#define END_MMU_FTR_SECTION_IFSET(msk)	END_MMU_FTR_SECTION((msk), (msk))
#define END_MMU_FTR_SECTION_IFCLR(msk)	END_MMU_FTR_SECTION((msk), 0)

/* MMU feature sections with alternatives, use BEGIN_FTR_SECTION to start */
#define MMU_FTR_SECTION_ELSE_NESTED(label)	FTR_SECTION_ELSE_NESTED(label)
#define MMU_FTR_SECTION_ELSE	MMU_FTR_SECTION_ELSE_NESTED(97)
#define ALT_MMU_FTR_SECTION_END_NESTED(msk, val, label)	\
	MAKE_FTR_SECTION_ENTRY(msk, val, label, __mmu_ftr_fixup)
#define ALT_MMU_FTR_SECTION_END_NESTED_IFSET(msk, label)	\
	ALT_MMU_FTR_SECTION_END_NESTED(msk, msk, label)
#define ALT_MMU_FTR_SECTION_END_NESTED_IFCLR(msk, label)	\
	ALT_MMU_FTR_SECTION_END_NESTED(msk, 0, label)
#define ALT_MMU_FTR_SECTION_END(msk, val)	\
	ALT_MMU_FTR_SECTION_END_NESTED(msk, val, 97)
#define ALT_MMU_FTR_SECTION_END_IFSET(msk)	\
	ALT_MMU_FTR_SECTION_END_NESTED_IFSET(msk, 97)
#define ALT_MMU_FTR_SECTION_END_IFCLR(msk)	\
	ALT_MMU_FTR_SECTION_END_NESTED_IFCLR(msk, 97)

/* Firmware feature dependent sections */
#define BEGIN_FW_FTR_SECTION_NESTED(label)	START_FTR_SECTION(label)
#define BEGIN_FW_FTR_SECTION			START_FTR_SECTION(97)

#define END_FW_FTR_SECTION_NESTED(msk, val, label) 		\
	FTR_SECTION_ELSE_NESTED(label)				\
	MAKE_FTR_SECTION_ENTRY(msk, val, label, __fw_ftr_fixup)

#define END_FW_FTR_SECTION(msk, val)		\
	END_FW_FTR_SECTION_NESTED(msk, val, 97)

#define END_FW_FTR_SECTION_IFSET(msk)	END_FW_FTR_SECTION((msk), (msk))
#define END_FW_FTR_SECTION_IFCLR(msk)	END_FW_FTR_SECTION((msk), 0)

/* Firmware feature sections with alternatives */
#define FW_FTR_SECTION_ELSE_NESTED(label)	FTR_SECTION_ELSE_NESTED(label)
#define FW_FTR_SECTION_ELSE	FTR_SECTION_ELSE_NESTED(97)
#define ALT_FW_FTR_SECTION_END_NESTED(msk, val, label)	\
	MAKE_FTR_SECTION_ENTRY(msk, val, label, __fw_ftr_fixup)
#define ALT_FW_FTR_SECTION_END_NESTED_IFSET(msk, label)	\
	ALT_FW_FTR_SECTION_END_NESTED(msk, msk, label)
#define ALT_FW_FTR_SECTION_END_NESTED_IFCLR(msk, label)	\
	ALT_FW_FTR_SECTION_END_NESTED(msk, 0, label)
#define ALT_FW_FTR_SECTION_END(msk, val)	\
	ALT_FW_FTR_SECTION_END_NESTED(msk, val, 97)
#define ALT_FW_FTR_SECTION_END_IFSET(msk)	\
	ALT_FW_FTR_SECTION_END_NESTED_IFSET(msk, 97)
#define ALT_FW_FTR_SECTION_END_IFCLR(msk)	\
	ALT_FW_FTR_SECTION_END_NESTED_IFCLR(msk, 97)

#ifndef __ASSEMBLY__

#define ASM_FTR_IF(section_if, section_else, msk, val)	\
	stringify_in_c(BEGIN_FTR_SECTION)			\
	section_if "; "						\
	stringify_in_c(FTR_SECTION_ELSE)			\
	section_else "; "					\
	stringify_in_c(ALT_FTR_SECTION_END((msk), (val)))

#define ASM_FTR_IFSET(section_if, section_else, msk)	\
	ASM_FTR_IF(section_if, section_else, (msk), (msk))

#define ASM_FTR_IFCLR(section_if, section_else, msk)	\
	ASM_FTR_IF(section_if, section_else, (msk), 0)

#define ASM_MMU_FTR_IF(section_if, section_else, msk, val)	\
	stringify_in_c(BEGIN_MMU_FTR_SECTION)			\
	section_if "; "						\
	stringify_in_c(MMU_FTR_SECTION_ELSE)			\
	section_else "; "					\
	stringify_in_c(ALT_MMU_FTR_SECTION_END((msk), (val)))

#define ASM_MMU_FTR_IFSET(section_if, section_else, msk)	\
	ASM_MMU_FTR_IF(section_if, section_else, (msk), (msk))

#define ASM_MMU_FTR_IFCLR(section_if, section_else, msk)	\
	ASM_MMU_FTR_IF(section_if, section_else, (msk), 0)

#endif /* __ASSEMBLY__ */

/* LWSYNC feature sections */
#define START_LWSYNC_SECTION(label)	label##1:
#define MAKE_LWSYNC_SECTION_ENTRY(label, sect)		\
label##2:						\
	.pushsection sect,"a";				\
	.align 2;					\
label##3:					       	\
	FTR_ENTRY_OFFSET label##1b-label##3b;		\
	.popsection;

#define STF_ENTRY_BARRIER_FIXUP_SECTION			\
953:							\
	.pushsection __stf_entry_barrier_fixup,"a";	\
	.align 2;					\
954:							\
	FTR_ENTRY_OFFSET 953b-954b;			\
	.popsection;

#define STF_EXIT_BARRIER_FIXUP_SECTION			\
955:							\
	.pushsection __stf_exit_barrier_fixup,"a";	\
	.align 2;					\
956:							\
	FTR_ENTRY_OFFSET 955b-956b;			\
	.popsection;

#define UACCESS_FLUSH_FIXUP_SECTION			\
959:							\
	.pushsection __uaccess_flush_fixup,"a";		\
	.align 2;					\
960:							\
	FTR_ENTRY_OFFSET 959b-960b;			\
	.popsection;

#define ENTRY_FLUSH_FIXUP_SECTION			\
957:							\
	.pushsection __entry_flush_fixup,"a";		\
	.align 2;					\
958:							\
	FTR_ENTRY_OFFSET 957b-958b;			\
	.popsection;

#define SCV_ENTRY_FLUSH_FIXUP_SECTION			\
957:							\
	.pushsection __scv_entry_flush_fixup,"a";	\
	.align 2;					\
958:							\
	FTR_ENTRY_OFFSET 957b-958b;			\
	.popsection;

#define RFI_FLUSH_FIXUP_SECTION				\
951:							\
	.pushsection __rfi_flush_fixup,"a";		\
	.align 2;					\
952:							\
	FTR_ENTRY_OFFSET 951b-952b;			\
	.popsection;

#define NOSPEC_BARRIER_FIXUP_SECTION			\
953:							\
	.pushsection __barrier_nospec_fixup,"a";	\
	.align 2;					\
954:							\
	FTR_ENTRY_OFFSET 953b-954b;			\
	.popsection;

#define START_BTB_FLUSH_SECTION			\
955:							\

#define END_BTB_FLUSH_SECTION			\
956:							\
	.pushsection __btb_flush_fixup,"a";	\
	.align 2;							\
957:						\
	FTR_ENTRY_OFFSET 955b-957b;			\
	FTR_ENTRY_OFFSET 956b-957b;			\
	.popsection;

#ifndef __ASSEMBLY__
#include <linux/types.h>

extern long stf_barrier_fallback;
extern long entry_flush_fallback;
extern long scv_entry_flush_fallback;
extern long __start___stf_entry_barrier_fixup, __stop___stf_entry_barrier_fixup;
extern long __start___stf_exit_barrier_fixup, __stop___stf_exit_barrier_fixup;
extern long __start___uaccess_flush_fixup, __stop___uaccess_flush_fixup;
extern long __start___entry_flush_fixup, __stop___entry_flush_fixup;
extern long __start___scv_entry_flush_fixup, __stop___scv_entry_flush_fixup;
extern long __start___rfi_flush_fixup, __stop___rfi_flush_fixup;
extern long __start___barrier_nospec_fixup, __stop___barrier_nospec_fixup;
extern long __start__btb_flush_fixup, __stop__btb_flush_fixup;

void apply_feature_fixups(void);
void update_mmu_feature_fixups(unsigned long mask);
void setup_feature_keys(void);
#endif

#endif /* __ASM_POWERPC_FEATURE_FIXUPS_H */