From 099122af4e29efb41e0db6cc2cd5a07278250e4f Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Fri, 24 Feb 2023 16:45:56 +0100 Subject: [PATCH 1/6] riscv: Clarify RISCV_ALTERNATIVE help text Clarify RISCV_ALTERNATIVE's help text by pointing out that code patching is not only done at boot time, but also module load time. Also point out that this is the minimal possible overhead. Signed-off-by: Andrew Jones Link: https://lore.kernel.org/r/20230224154601.88163-2-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index c5e42cc37604..04898c50ef1d 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -379,8 +379,8 @@ config RISCV_ALTERNATIVE help This Kconfig allows the kernel to automatically patch the errata required by the execution platform at run time. The - code patching is performed once in the boot stages. It means - that the overhead from this mechanism is just taken once. + code patching overhead is minimal, as it's only done once + at boot and once on each module load. config RISCV_ALTERNATIVE_EARLY bool From a3d095ac00faee0deb575ba053f0567b0d124d0b Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Fri, 24 Feb 2023 16:45:57 +0100 Subject: [PATCH 2/6] riscv: Rename Kconfig.erratas to Kconfig.errata Errata is already plural for erratum. Rename it to make the grammar gooder. Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner Link: https://lore.kernel.org/r/20230224154601.88163-3-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 2 +- arch/riscv/{Kconfig.erratas => Kconfig.errata} | 0 2 files changed, 1 insertion(+), 1 deletion(-) rename arch/riscv/{Kconfig.erratas => Kconfig.errata} (100%) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 04898c50ef1d..ab78f677f187 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -245,7 +245,7 @@ config AS_HAS_INSN def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) source "arch/riscv/Kconfig.socs" -source "arch/riscv/Kconfig.erratas" +source "arch/riscv/Kconfig.errata" menu "Platform type" diff --git a/arch/riscv/Kconfig.erratas b/arch/riscv/Kconfig.errata similarity index 100% rename from arch/riscv/Kconfig.erratas rename to arch/riscv/Kconfig.errata From ce06b42a4a96d46d4844f2b630af7d349a924a58 Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Fri, 24 Feb 2023 16:45:58 +0100 Subject: [PATCH 3/6] riscv: alternatives: Remove unnecessary define and unused struct A define and a struct were introduced with commit 6f4eea90465a ("riscv: Introduce alternative mechanism to apply errata solution"), which introduced alternatives to RISC-V. The define is used for an arbitrary string length, specific to sifive errata, so just use the number directly there instead. The struct has never been used, so remove it. Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner Link: https://lore.kernel.org/r/20230224154601.88163-4-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt --- arch/riscv/errata/sifive/errata.c | 2 +- arch/riscv/include/asm/alternative.h | 7 ------- 2 files changed, 1 insertion(+), 8 deletions(-) diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c index da55cb247e89..69dfb38e4f06 100644 --- a/arch/riscv/errata/sifive/errata.c +++ b/arch/riscv/errata/sifive/errata.c @@ -14,7 +14,7 @@ #include struct errata_info_t { - char name[ERRATA_STRING_LENGTH_MAX]; + char name[32]; bool (*check_func)(unsigned long arch_id, unsigned long impid); }; diff --git a/arch/riscv/include/asm/alternative.h b/arch/riscv/include/asm/alternative.h index b8648d4f2ac1..3beef400a971 100644 --- a/arch/riscv/include/asm/alternative.h +++ b/arch/riscv/include/asm/alternative.h @@ -6,8 +6,6 @@ #ifndef __ASM_ALTERNATIVE_H #define __ASM_ALTERNATIVE_H -#define ERRATA_STRING_LENGTH_MAX 32 - #include #ifndef __ASSEMBLY__ @@ -43,11 +41,6 @@ struct alt_entry { u32 errata_id; /* The errata id */ }; -struct errata_checkfunc_id { - unsigned long vendor_id; - bool (*func)(struct alt_entry *alt); -}; - void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, unsigned long archid, unsigned long impid, unsigned int stage); From ff19a8dee196d757dbc32a946843260f0b784ca3 Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Fri, 24 Feb 2023 16:45:59 +0100 Subject: [PATCH 4/6] riscv: alternatives: Rename errata_id to patch_id Alternatives are used for both errata and cpufeatures. Use a more generic name, 'patch_id', as in "ID of code patching site", to avoid confusion when alternatives are used for cpufeatures. Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner Link: https://lore.kernel.org/r/20230224154601.88163-5-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 6 +- arch/riscv/errata/sifive/errata.c | 6 +- arch/riscv/errata/thead/errata.c | 4 +- arch/riscv/include/asm/alternative-macros.h | 72 ++++++++++----------- arch/riscv/include/asm/alternative.h | 4 +- arch/riscv/kernel/cpufeature.c | 6 +- 6 files changed, 49 insertions(+), 49 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index ab78f677f187..69797e6eed6f 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -378,9 +378,9 @@ config RISCV_ALTERNATIVE depends on !XIP_KERNEL help This Kconfig allows the kernel to automatically patch the - errata required by the execution platform at run time. The - code patching overhead is minimal, as it's only done once - at boot and once on each module load. + erratum or cpufeature required by the execution platform at run + time. The code patching overhead is minimal, as it's only done + once at boot and once on each module load. config RISCV_ALTERNATIVE_EARLY bool diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c index 69dfb38e4f06..7fa7b8b6a811 100644 --- a/arch/riscv/errata/sifive/errata.c +++ b/arch/riscv/errata/sifive/errata.c @@ -101,12 +101,12 @@ void __init_or_module sifive_errata_patch_func(struct alt_entry *begin, for (alt = begin; alt < end; alt++) { if (alt->vendor_id != SIFIVE_VENDOR_ID) continue; - if (alt->errata_id >= ERRATA_SIFIVE_NUMBER) { - WARN(1, "This errata id:%d is not in kernel errata list", alt->errata_id); + if (alt->patch_id >= ERRATA_SIFIVE_NUMBER) { + WARN(1, "This errata id:%d is not in kernel errata list", alt->patch_id); continue; } - tmp = (1U << alt->errata_id); + tmp = (1U << alt->patch_id); if (cpu_req_errata & tmp) { mutex_lock(&text_mutex); patch_text_nosync(ALT_OLD_PTR(alt), ALT_ALT_PTR(alt), diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c index 3b96a06d3c54..7e8d50ebb71a 100644 --- a/arch/riscv/errata/thead/errata.c +++ b/arch/riscv/errata/thead/errata.c @@ -93,10 +93,10 @@ void __init_or_module thead_errata_patch_func(struct alt_entry *begin, struct al for (alt = begin; alt < end; alt++) { if (alt->vendor_id != THEAD_VENDOR_ID) continue; - if (alt->errata_id >= ERRATA_THEAD_NUMBER) + if (alt->patch_id >= ERRATA_THEAD_NUMBER) continue; - tmp = (1U << alt->errata_id); + tmp = (1U << alt->patch_id); if (cpu_req_errata & tmp) { oldptr = ALT_OLD_PTR(alt); altptr = ALT_ALT_PTR(alt); diff --git a/arch/riscv/include/asm/alternative-macros.h b/arch/riscv/include/asm/alternative-macros.h index 51c6867e02f3..993a44a8fdac 100644 --- a/arch/riscv/include/asm/alternative-macros.h +++ b/arch/riscv/include/asm/alternative-macros.h @@ -6,18 +6,18 @@ #ifdef __ASSEMBLY__ -.macro ALT_ENTRY oldptr newptr vendor_id errata_id new_len +.macro ALT_ENTRY oldptr newptr vendor_id patch_id new_len .4byte \oldptr - . .4byte \newptr - . .2byte \vendor_id .2byte \new_len - .4byte \errata_id + .4byte \patch_id .endm -.macro ALT_NEW_CONTENT vendor_id, errata_id, enable = 1, new_c : vararg +.macro ALT_NEW_CONTENT vendor_id, patch_id, enable = 1, new_c : vararg .if \enable .pushsection .alternative, "a" - ALT_ENTRY 886b, 888f, \vendor_id, \errata_id, 889f - 888f + ALT_ENTRY 886b, 888f, \vendor_id, \patch_id, 889f - 888f .popsection .subsection 1 888 : @@ -33,7 +33,7 @@ .endif .endm -.macro ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, enable +.macro ALTERNATIVE_CFG old_c, new_c, vendor_id, patch_id, enable 886 : .option push .option norvc @@ -41,13 +41,13 @@ \old_c .option pop 887 : - ALT_NEW_CONTENT \vendor_id, \errata_id, \enable, \new_c + ALT_NEW_CONTENT \vendor_id, \patch_id, \enable, \new_c .endm -.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 - ALTERNATIVE_CFG "\old_c", "\new_c_1", \vendor_id_1, \errata_id_1, \enable_1 - ALT_NEW_CONTENT \vendor_id_2, \errata_id_2, \enable_2, \new_c_2 +.macro ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, patch_id_1, enable_1, \ + new_c_2, vendor_id_2, patch_id_2, enable_2 + ALTERNATIVE_CFG "\old_c", "\new_c_1", \vendor_id_1, \patch_id_1, \enable_1 + ALT_NEW_CONTENT \vendor_id_2, \patch_id_2, \enable_2, \new_c_2 .endm #define __ALTERNATIVE_CFG(...) ALTERNATIVE_CFG __VA_ARGS__ @@ -58,17 +58,17 @@ #include #include -#define ALT_ENTRY(oldptr, newptr, vendor_id, errata_id, newlen) \ +#define ALT_ENTRY(oldptr, newptr, vendor_id, patch_id, newlen) \ ".4byte ((" oldptr ") - .) \n" \ ".4byte ((" newptr ") - .) \n" \ ".2byte " vendor_id "\n" \ ".2byte " newlen "\n" \ - ".4byte " errata_id "\n" + ".4byte " patch_id "\n" -#define ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) \ +#define ALT_NEW_CONTENT(vendor_id, patch_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") \ + ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(patch_id), "889f - 888f") \ ".popsection\n" \ ".subsection 1\n" \ "888 :\n" \ @@ -83,7 +83,7 @@ ".previous\n" \ ".endif\n" -#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, enable) \ +#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, enable) \ "886 :\n" \ ".option push\n" \ ".option norvc\n" \ @@ -91,22 +91,22 @@ old_c "\n" \ ".option pop\n" \ "887 :\n" \ - ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) + ALT_NEW_CONTENT(vendor_id, patch_id, enable, new_c) -#define __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) \ - __ALTERNATIVE_CFG(old_c, new_c_1, vendor_id_1, errata_id_1, enable_1) \ - ALT_NEW_CONTENT(vendor_id_2, errata_id_2, enable_2, new_c_2) +#define __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, enable_1, \ + new_c_2, vendor_id_2, patch_id_2, enable_2) \ + __ALTERNATIVE_CFG(old_c, new_c_1, vendor_id_1, patch_id_1, enable_1) \ + ALT_NEW_CONTENT(vendor_id_2, patch_id_2, enable_2, new_c_2) #endif /* __ASSEMBLY__ */ -#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)) +#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, CONFIG_k) \ + __ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, IS_ENABLED(CONFIG_k)) -#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_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, CONFIG_k_1, \ + new_c_2, vendor_id_2, patch_id_2, CONFIG_k_2) \ + __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, IS_ENABLED(CONFIG_k_1), \ + new_c_2, vendor_id_2, patch_id_2, IS_ENABLED(CONFIG_k_2)) #else /* CONFIG_RISCV_ALTERNATIVE */ #ifdef __ASSEMBLY__ @@ -137,19 +137,19 @@ /* * Usage: - * ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k) + * ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k) * in the assembly code. Otherwise, - * asm(ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k)); + * asm(ALTERNATIVE(old_content, new_content, vendor_id, patch_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 + * patch_id: The patch ID (erratum ID or cpufeature ID). + * CONFIG_k: The Kconfig of this patch ID. 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) +#define ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k) \ + _ALTERNATIVE_CFG(old_content, new_content, vendor_id, patch_id, CONFIG_k) /* * A vendor wants to replace an old_content, but another vendor has used @@ -158,9 +158,9 @@ * on the following sample code and then replace ALTERNATIVE() with * ALTERNATIVE_2() to append its customized content. */ -#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) +#define ALTERNATIVE_2(old_content, new_content_1, vendor_id_1, patch_id_1, CONFIG_k_1, \ + new_content_2, vendor_id_2, patch_id_2, CONFIG_k_2) \ + _ALTERNATIVE_CFG_2(old_content, new_content_1, vendor_id_1, patch_id_1, CONFIG_k_1, \ + new_content_2, vendor_id_2, patch_id_2, CONFIG_k_2) #endif diff --git a/arch/riscv/include/asm/alternative.h b/arch/riscv/include/asm/alternative.h index 3beef400a971..c8dea9e94310 100644 --- a/arch/riscv/include/asm/alternative.h +++ b/arch/riscv/include/asm/alternative.h @@ -36,9 +36,9 @@ void riscv_alternative_fix_offsets(void *alt_ptr, unsigned int len, struct alt_entry { s32 old_offset; /* offset relative to original instruction or data */ s32 alt_offset; /* offset relative to replacement instruction or data */ - u16 vendor_id; /* cpu vendor id */ + u16 vendor_id; /* CPU vendor ID */ u16 alt_len; /* The replacement size */ - u32 errata_id; /* The errata id */ + u32 patch_id; /* The patch ID (erratum ID or cpufeature ID) */ }; void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 59d58ee0f68d..059db20b28ca 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -282,13 +282,13 @@ void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin, for (alt = begin; alt < end; alt++) { if (alt->vendor_id != 0) continue; - if (alt->errata_id >= RISCV_ISA_EXT_MAX) { + if (alt->patch_id >= RISCV_ISA_EXT_MAX) { WARN(1, "This extension id:%d is not in ISA extension list", - alt->errata_id); + alt->patch_id); continue; } - if (!__riscv_isa_extension_available(NULL, alt->errata_id)) + if (!__riscv_isa_extension_available(NULL, alt->patch_id)) continue; oldptr = ALT_OLD_PTR(alt); From 28ea374da1d94dfe1253b83aa2d16b5a97fb7c4e Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Fri, 24 Feb 2023 16:46:00 +0100 Subject: [PATCH 5/6] riscv: lib: Include hwcap.h directly When using alternatives for cpufeatures we should include hwcap.h directly, rather than through errata_list.h. Opportunistically drop an unused include too. Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner Link: https://lore.kernel.org/r/20230224154601.88163-6-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt --- arch/riscv/lib/strcmp.S | 3 +-- arch/riscv/lib/strlen.S | 3 +-- arch/riscv/lib/strncmp.S | 3 +-- 3 files changed, 3 insertions(+), 6 deletions(-) diff --git a/arch/riscv/lib/strcmp.S b/arch/riscv/lib/strcmp.S index c42a8412547f..687b2bea5c43 100644 --- a/arch/riscv/lib/strcmp.S +++ b/arch/riscv/lib/strcmp.S @@ -2,9 +2,8 @@ #include #include -#include #include -#include +#include /* int strcmp(const char *cs, const char *ct) */ SYM_FUNC_START(strcmp) diff --git a/arch/riscv/lib/strlen.S b/arch/riscv/lib/strlen.S index 15bb8f3aa959..db3d42d99b78 100644 --- a/arch/riscv/lib/strlen.S +++ b/arch/riscv/lib/strlen.S @@ -2,9 +2,8 @@ #include #include -#include #include -#include +#include /* int strlen(const char *s) */ SYM_FUNC_START(strlen) diff --git a/arch/riscv/lib/strncmp.S b/arch/riscv/lib/strncmp.S index 7ac2f667285a..aba5b3148621 100644 --- a/arch/riscv/lib/strncmp.S +++ b/arch/riscv/lib/strncmp.S @@ -2,9 +2,8 @@ #include #include -#include #include -#include +#include /* int strncmp(const char *cs, const char *ct, size_t count) */ SYM_FUNC_START(strncmp) From 816a69744102bc886edc3557d00e840e3e35e7d5 Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Fri, 24 Feb 2023 16:46:01 +0100 Subject: [PATCH 6/6] riscv: cpufeature: Drop errata_list.h and other unused includes Drop errata_list.h, since cpufeature.c includes hwcap.h directly to get cpufeature IDs. And, while there, prune the rest of the unused includes too. Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner Link: https://lore.kernel.org/r/20230224154601.88163-7-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/cpufeature.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 059db20b28ca..6569d963fc7d 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -8,20 +8,15 @@ #include #include -#include #include #include #include #include #include #include -#include #include #include -#include #include -#include -#include #define NUM_ALPHA_EXTS ('z' - 'a' + 1)