[mirror_ubuntu-jammy-kernel.git] / arch / riscv / include / asm / alternative-macros.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ALTERNATIVE_MACROS_H
#define __ASM_ALTERNATIVE_MACROS_H

#ifdef CONFIG_RISCV_ERRATA_ALTERNATIVE

#ifdef __ASSEMBLY__

.macro ALT_ENTRY oldptr newptr vendor_id errata_id new_len
	RISCV_PTR \oldptr
	RISCV_PTR \newptr
	REG_ASM \vendor_id
	REG_ASM \new_len
	.word	\errata_id
.endm

.macro ALT_NEW_CONTENT vendor_id, errata_id, enable = 1, new_c : vararg
	.if \enable
	.pushsection .alternative, "a"
	ALT_ENTRY 886b, 888f, \vendor_id, \errata_id, 889f - 888f
	.popsection
	.subsection 1
888 :
	\new_c
889 :
	.previous
	.org    . - (889b - 888b) + (887b - 886b)
	.org    . - (887b - 886b) + (889b - 888b)
	.endif
.endm

.macro __ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, enable
886 :
	\old_c
887 :
	ALT_NEW_CONTENT \vendor_id, \errata_id, \enable, \new_c
.endm

#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	__ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k)

#else /* !__ASSEMBLY__ */

#include <asm/asm.h>
#include <linux/stringify.h>

#define ALT_ENTRY(oldptr, newptr, vendor_id, errata_id, newlen) \
	RISCV_PTR " " oldptr "\n" \
	RISCV_PTR " " newptr "\n" \
	REG_ASM " " vendor_id "\n" \
	REG_ASM " " newlen "\n" \
	".word " errata_id "\n"

#define ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) \
	".if " __stringify(enable) " == 1\n"				\
	".pushsection .alternative, \"a\"\n"				\
	ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(errata_id), "889f - 888f") \
	".popsection\n"							\
	".subsection 1\n"						\
	"888 :\n"							\
	new_c "\n"							\
	"889 :\n"							\
	".previous\n"							\
	".org	. - (887b - 886b) + (889b - 888b)\n"			\
	".org	. - (889b - 888b) + (887b - 886b)\n"			\
	".endif\n"

#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, enable) \
	"886 :\n"	\
	old_c "\n"	\
	"887 :\n"	\
	ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c)

#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k)	\
	__ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k))

#endif /* __ASSEMBLY__ */

#else /* !CONFIG_RISCV_ERRATA_ALTERNATIVE*/
#ifdef __ASSEMBLY__

.macro __ALTERNATIVE_CFG old_c
	\old_c
.endm

#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	__ALTERNATIVE_CFG old_c

#else /* !__ASSEMBLY__ */

#define __ALTERNATIVE_CFG(old_c)  \
	old_c "\n"

#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	__ALTERNATIVE_CFG(old_c)

#endif /* __ASSEMBLY__ */
#endif /* CONFIG_RISCV_ERRATA_ALTERNATIVE */
/*
 * Usage:
 *   ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k)
 * in the assembly code. Otherwise,
 *   asm(ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k));
 *
 * old_content: The old content which is probably replaced with new content.
 * new_content: The new content.
 * vendor_id: The CPU vendor ID.
 * errata_id: The errata ID.
 * CONFIG_k: The Kconfig of this errata. When Kconfig is disabled, the old
 *	     content will alwyas be executed.
 */
#define ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k) \
	_ALTERNATIVE_CFG(old_content, new_content, vendor_id, errata_id, CONFIG_k)

/*
 * A vendor wants to replace an old_content, but another vendor has used
 * ALTERNATIVE() to patch its customized content at the same location. In
 * this case, this vendor can create a new macro ALTERNATIVE_2() based
 * on the following sample code and then replace ALTERNATIVE() with
 * ALTERNATIVE_2() to append its customized content.
 *
 * .macro __ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, errata_id_1, enable_1, \
 *                                   new_c_2, vendor_id_2, errata_id_2, enable_2
 * 886 :
 *      \old_c
 * 887 :
 *      ALT_NEW_CONTENT \vendor_id_1, \errata_id_1, \enable_1, \new_c_1
 *      ALT_NEW_CONTENT \vendor_id_2, \errata_id_2, \enable_2, \new_c_2
 * .endm
 *
 * #define _ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, errata_id_1, CONFIG_k_1, \
 *                                   new_c_2, vendor_id_2, errata_id_2, CONFIG_k_2) \
 *        __ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, errata_id_1, IS_ENABLED(CONFIG_k_1), \
 *                                   new_c_2, vendor_id_2, errata_id_2, IS_ENABLED(CONFIG_k_2) \
 *
 * #define ALTERNATIVE_2(old_content, new_content_1, vendor_id_1, errata_id_1, CONFIG_k_1, \
 *                                    new_content_2, vendor_id_2, errata_id_2, CONFIG_k_2) \
 *         _ALTERNATIVE_CFG_2(old_content, new_content_1, vendor_id_1, errata_id_1, CONFIG_k_1, \
 *                                         new_content_2, vendor_id_2, errata_id_2, CONFIG_k_2)
 *
 */
#endif
Commit	Line	Data
6f4eea90 VC	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef __ASM_ALTERNATIVE_MACROS_H
	3	#define __ASM_ALTERNATIVE_MACROS_H
	4
	5	#ifdef CONFIG_RISCV_ERRATA_ALTERNATIVE
	6
	7	#ifdef __ASSEMBLY__
	8
	9	.macro ALT_ENTRY oldptr newptr vendor_id errata_id new_len
	10	RISCV_PTR \oldptr
	11	RISCV_PTR \newptr
	12	REG_ASM \vendor_id
	13	REG_ASM \new_len
	14	.word \errata_id
	15	.endm
	16
	17	.macro ALT_NEW_CONTENT vendor_id, errata_id, enable = 1, new_c : vararg
	18	.if \enable
	19	.pushsection .alternative, "a"
	20	ALT_ENTRY 886b, 888f, \vendor_id, \errata_id, 889f - 888f
	21	.popsection
	22	.subsection 1
	23	888 :
	24	\new_c
	25	889 :
	26	.previous
	27	.org . - (889b - 888b) + (887b - 886b)
	28	.org . - (887b - 886b) + (889b - 888b)
	29	.endif
	30	.endm
	31
	32	.macro __ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, enable
	33	886 :
	34	\old_c
	35	887 :
	36	ALT_NEW_CONTENT \vendor_id, \errata_id, \enable, \new_c
	37	.endm
	38
	39	#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	40	__ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k)
	41
	42	#else /* !__ASSEMBLY__ */
	43
	44	#include <asm/asm.h>
	45	#include <linux/stringify.h>
	46
	47	#define ALT_ENTRY(oldptr, newptr, vendor_id, errata_id, newlen) \
	48	RISCV_PTR " " oldptr "\n" \
	49	RISCV_PTR " " newptr "\n" \
	50	REG_ASM " " vendor_id "\n" \
	51	REG_ASM " " newlen "\n" \
	52	".word " errata_id "\n"
	53
858cf860	54	#define ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) \
6f4eea90 VC	55	".if " __stringify(enable) " == 1\n" \
	56	".pushsection .alternative, \"a\"\n" \
	57	ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(errata_id), "889f - 888f") \
	58	".popsection\n" \
	59	".subsection 1\n" \
	60	"888 :\n" \
	61	new_c "\n" \
	62	"889 :\n" \
	63	".previous\n" \
	64	".org . - (887b - 886b) + (889b - 888b)\n" \
	65	".org . - (889b - 888b) + (887b - 886b)\n" \
	66	".endif\n"
	67
	68	#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, enable) \
	69	"886 :\n" \
	70	old_c "\n" \
	71	"887 :\n" \
858cf860	72	ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c)
6f4eea90 VC	73
	74	#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	75	__ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k))
	76
	77	#endif /* __ASSEMBLY__ */
	78
	79	#else /* !CONFIG_RISCV_ERRATA_ALTERNATIVE*/
	80	#ifdef __ASSEMBLY__
	81
	82	.macro __ALTERNATIVE_CFG old_c
	83	\old_c
	84	.endm
	85
	86	#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	87	__ALTERNATIVE_CFG old_c
	88
	89	#else /* !__ASSEMBLY__ */
	90
	91	#define __ALTERNATIVE_CFG(old_c) \
	92	old_c "\n"
	93
	94	#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \
	95	__ALTERNATIVE_CFG(old_c)
	96
	97	#endif /* __ASSEMBLY__ */
	98	#endif /* CONFIG_RISCV_ERRATA_ALTERNATIVE */
	99	/*
	100	* Usage:
	101	* ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k)
	102	* in the assembly code. Otherwise,
	103	* asm(ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k));
	104	*
	105	* old_content: The old content which is probably replaced with new content.
	106	* new_content: The new content.
	107	* vendor_id: The CPU vendor ID.
	108	* errata_id: The errata ID.
	109	* CONFIG_k: The Kconfig of this errata. When Kconfig is disabled, the old
	110	* content will alwyas be executed.
	111	*/
	112	#define ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k) \
	113	_ALTERNATIVE_CFG(old_content, new_content, vendor_id, errata_id, CONFIG_k)
	114
	115	/*
	116	* A vendor wants to replace an old_content, but another vendor has used
	117	* ALTERNATIVE() to patch its customized content at the same location. In
	118	* this case, this vendor can create a new macro ALTERNATIVE_2() based
	119	* on the following sample code and then replace ALTERNATIVE() with
	120	* ALTERNATIVE_2() to append its customized content.
	121	*
	122	* .macro __ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, errata_id_1, enable_1, \
	123	* new_c_2, vendor_id_2, errata_id_2, enable_2
	124	* 886 :
	125	* \old_c
	126	* 887 :
	127	* ALT_NEW_CONTENT \vendor_id_1, \errata_id_1, \enable_1, \new_c_1
	128	* ALT_NEW_CONTENT \vendor_id_2, \errata_id_2, \enable_2, \new_c_2
	129	* .endm
	130	*
	131	* #define _ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, errata_id_1, CONFIG_k_1, \
	132	* new_c_2, vendor_id_2, errata_id_2, CONFIG_k_2) \
	133	* __ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, errata_id_1, IS_ENABLED(CONFIG_k_1), \
	134	* new_c_2, vendor_id_2, errata_id_2, IS_ENABLED(CONFIG_k_2) \
	135	*
	136	* #define ALTERNATIVE_2(old_content, new_content_1, vendor_id_1, errata_id_1, CONFIG_k_1, \
137	* new_content_2, vendor_id_2, errata_id_2, CONFIG_k_2) \
138	* _ALTERNATIVE_CFG_2(old_content, new_content_1, vendor_id_1, errata_id_1, CONFIG_k_1, \
139	* new_content_2, vendor_id_2, errata_id_2, CONFIG_k_2)
140	*
141	*/
142	#endif