Separate vendor extensions out into one struct per vendor instead of adding vendor extensions onto riscv_isa_ext.
Add a hidden config RISCV_ISA_VENDOR_EXT to conditionally include this code.
The xtheadvector vendor extension is added using these changes.
Signed-off-by: Charlie Jenkins charlie@rivosinc.com --- arch/riscv/Kconfig | 2 + arch/riscv/Kconfig.vendor | 19 +++++ arch/riscv/include/asm/cpufeature.h | 18 +++++ arch/riscv/include/asm/vendor_extensions.h | 34 +++++++++ arch/riscv/include/asm/vendor_extensions/thead.h | 16 ++++ arch/riscv/kernel/Makefile | 2 + arch/riscv/kernel/cpufeature.c | 93 +++++++++++++++++++----- arch/riscv/kernel/vendor_extensions.c | 18 +++++ arch/riscv/kernel/vendor_extensions/Makefile | 3 + arch/riscv/kernel/vendor_extensions/thead.c | 18 +++++ 10 files changed, 203 insertions(+), 20 deletions(-)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index be09c8836d56..fec86fba3acd 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -759,6 +759,8 @@ config RISCV_EFFICIENT_UNALIGNED_ACCESS
endchoice
+source "arch/riscv/Kconfig.vendor" + endmenu # "Platform type"
menu "Kernel features" diff --git a/arch/riscv/Kconfig.vendor b/arch/riscv/Kconfig.vendor new file mode 100644 index 000000000000..85ac30496b0e --- /dev/null +++ b/arch/riscv/Kconfig.vendor @@ -0,0 +1,19 @@ +menu "Vendor extensions" + +config RISCV_ISA_VENDOR_EXT + bool + +menu "T-Head" +config RISCV_ISA_VENDOR_EXT_THEAD + bool "T-Head vendor extension support" + select RISCV_ISA_VENDOR_EXT + default y + help + Say N here to disable detection of and support for all T-Head vendor + extensions. Without this option enabled, T-Head vendor extensions will + not be detected at boot and their presence not reported to userspace. + + If you don't know what to do here, say Y. +endmenu + +endmenu diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h index 0c4f08577015..fedd479ccfd1 100644 --- a/arch/riscv/include/asm/cpufeature.h +++ b/arch/riscv/include/asm/cpufeature.h @@ -35,6 +35,24 @@ extern u32 riscv_vlenb_of;
void riscv_user_isa_enable(void);
+#define _RISCV_ISA_EXT_DATA(_name, _id, _subset_exts, _subset_exts_size) { \ + .name = #_name, \ + .property = #_name, \ + .id = _id, \ + .subset_ext_ids = _subset_exts, \ + .subset_ext_size = _subset_exts_size \ +} + +#define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0) + +/* Used to declare pure "lasso" extension (Zk for instance) */ +#define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \ + _RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, ARRAY_SIZE(_bundled_exts)) + +/* Used to declare extensions that are a superset of other extensions (Zvbb for instance) */ +#define __RISCV_ISA_EXT_SUPERSET(_name, _id, _sub_exts) \ + _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts)) + #if defined(CONFIG_RISCV_MISALIGNED) bool check_unaligned_access_emulated_all_cpus(void); void unaligned_emulation_finish(void); diff --git a/arch/riscv/include/asm/vendor_extensions.h b/arch/riscv/include/asm/vendor_extensions.h new file mode 100644 index 000000000000..bf4dac66e6e6 --- /dev/null +++ b/arch/riscv/include/asm/vendor_extensions.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright 2024 Rivos, Inc + */ + +#ifndef _ASM_VENDOR_EXTENSIONS_H +#define _ASM_VENDOR_EXTENSIONS_H + +#include <asm/cpufeature.h> + +#include <linux/array_size.h> +#include <linux/types.h> + +/* + * The extension keys of each vendor must be strictly less than this value. + */ +#define RISCV_ISA_VENDOR_EXT_MAX 32 + +struct riscv_isavendorinfo { + DECLARE_BITMAP(isa, RISCV_ISA_VENDOR_EXT_MAX); +}; + +struct riscv_isa_vendor_ext_data_list { + const size_t ext_data_count; + const struct riscv_isa_ext_data *ext_data; + struct riscv_isavendorinfo per_hart_isa_bitmap[NR_CPUS]; + struct riscv_isavendorinfo all_harts_isa_bitmap; +}; + +extern struct riscv_isa_vendor_ext_data_list *riscv_isa_vendor_ext_list[]; + +extern const size_t riscv_isa_vendor_ext_list_size; + +#endif /* _ASM_VENDOR_EXTENSIONS_H */ diff --git a/arch/riscv/include/asm/vendor_extensions/thead.h b/arch/riscv/include/asm/vendor_extensions/thead.h new file mode 100644 index 000000000000..48421d1553ad --- /dev/null +++ b/arch/riscv/include/asm/vendor_extensions/thead.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_RISCV_VENDOR_EXTENSIONS_THEAD_H +#define _ASM_RISCV_VENDOR_EXTENSIONS_THEAD_H + +#include <asm/vendor_extensions.h> + +#include <linux/types.h> + +/* + * Extension keys must be strictly less than RISCV_ISA_VENDOR_EXT_MAX. + */ +#define RISCV_ISA_VENDOR_EXT_XTHEADVECTOR 0 + +extern struct riscv_isa_vendor_ext_data_list riscv_isa_vendor_ext_list_thead; + +#endif diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 81d94a8ee10f..53361c50fb46 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -58,6 +58,8 @@ obj-y += riscv_ksyms.o obj-y += stacktrace.o obj-y += cacheinfo.o obj-y += patch.o +obj-y += vendor_extensions.o +obj-y += vendor_extensions/ obj-y += probes/ obj-y += tests/ obj-$(CONFIG_MMU) += vdso.o vdso/ diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 6c143ea9592b..6019b2527c46 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -24,6 +24,7 @@ #include <asm/processor.h> #include <asm/sbi.h> #include <asm/vector.h> +#include <asm/vendor_extensions.h>
#define NUM_ALPHA_EXTS ('z' - 'a' + 1)
@@ -102,24 +103,6 @@ static bool riscv_isa_extension_check(int id) return true; }
-#define _RISCV_ISA_EXT_DATA(_name, _id, _subset_exts, _subset_exts_size) { \ - .name = #_name, \ - .property = #_name, \ - .id = _id, \ - .subset_ext_ids = _subset_exts, \ - .subset_ext_size = _subset_exts_size \ -} - -#define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0) - -/* Used to declare pure "lasso" extension (Zk for instance) */ -#define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \ - _RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, ARRAY_SIZE(_bundled_exts)) - -/* Used to declare extensions that are a superset of other extensions (Zvbb for instance) */ -#define __RISCV_ISA_EXT_SUPERSET(_name, _id, _sub_exts) \ - _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts)) - static const unsigned int riscv_zk_bundled_exts[] = { RISCV_ISA_EXT_ZBKB, RISCV_ISA_EXT_ZBKC, @@ -353,6 +336,21 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc bool ext_long = false, ext_err = false;
switch (*ext) { + case 'x': + case 'X': + if (acpi_disabled) + pr_warn_once("Vendor extensions are ignored in riscv,isa. Use riscv,isa-extensions instead."); + /* + * To skip an extension, we find its end. + * As multi-letter extensions must be split from other multi-letter + * extensions with an "_", the end of a multi-letter extension will + * either be the null character or the "_" at the start of the next + * multi-letter extension. + */ + for (; *isa && *isa != '_'; ++isa) + ; + ext_err = true; + break; case 's': /* * Workaround for invalid single-letter 's' & 'u' (QEMU). @@ -368,8 +366,6 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc } fallthrough; case 'S': - case 'x': - case 'X': case 'z': case 'Z': /* @@ -572,6 +568,59 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap) acpi_put_table((struct acpi_table_header *)rhct); }
+static void __init riscv_fill_cpu_vendor_ext(struct device_node *cpu_node, int cpu) +{ + if (!IS_ENABLED(CONFIG_RISCV_ISA_VENDOR_EXT)) + return; + + for (int i = 0; i < riscv_isa_vendor_ext_list_size; i++) { + struct riscv_isa_vendor_ext_data_list *ext_list = riscv_isa_vendor_ext_list[i]; + + for (int j = 0; j < ext_list->ext_data_count; j++) { + const struct riscv_isa_ext_data ext = ext_list->ext_data[j]; + struct riscv_isavendorinfo *isavendorinfo = &ext_list->per_hart_isa_bitmap[cpu]; + + if (of_property_match_string(cpu_node, "riscv,isa-extensions", + ext.property) < 0) + continue; + + /* + * Assume that subset extensions are all members of the + * same vendor. + */ + if (ext.subset_ext_size) + for (int k = 0; k < ext.subset_ext_size; k++) + set_bit(ext.subset_ext_ids[k], isavendorinfo->isa); + + set_bit(ext.id, isavendorinfo->isa); + } + } +} + +static void __init riscv_fill_vendor_ext_list(int cpu) +{ + static bool first = true; + + if (!IS_ENABLED(CONFIG_RISCV_ISA_VENDOR_EXT)) + return; + + for (int i = 0; i < riscv_isa_vendor_ext_list_size; i++) { + struct riscv_isa_vendor_ext_data_list *ext_list = riscv_isa_vendor_ext_list[i]; + + if (first) { + bitmap_copy(ext_list->all_harts_isa_bitmap.isa, + ext_list->per_hart_isa_bitmap[cpu].isa, + RISCV_ISA_VENDOR_EXT_MAX); + first = false; + } else { + bitmap_and(ext_list->all_harts_isa_bitmap.isa, + ext_list->all_harts_isa_bitmap.isa, + ext_list->per_hart_isa_bitmap[cpu].isa, + RISCV_ISA_VENDOR_EXT_MAX); + } + } +} + static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap) { unsigned int cpu; @@ -615,6 +664,8 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap) } }
+ riscv_fill_cpu_vendor_ext(cpu_node, cpu); + of_node_put(cpu_node);
/* @@ -630,6 +681,8 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap) bitmap_copy(riscv_isa, isainfo->isa, RISCV_ISA_EXT_MAX); else bitmap_and(riscv_isa, riscv_isa, isainfo->isa, RISCV_ISA_EXT_MAX); + + riscv_fill_vendor_ext_list(cpu); }
if (bitmap_empty(riscv_isa, RISCV_ISA_EXT_MAX)) diff --git a/arch/riscv/kernel/vendor_extensions.c b/arch/riscv/kernel/vendor_extensions.c new file mode 100644 index 000000000000..03ba7949a07f --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2024 Rivos, Inc + */ + +#include <asm/vendor_extensions.h> +#include <asm/vendor_extensions/thead.h> + +#include <linux/array_size.h> +#include <linux/types.h> + +struct riscv_isa_vendor_ext_data_list *riscv_isa_vendor_ext_list[] = { +#ifdef CONFIG_RISCV_ISA_VENDOR_EXT_THEAD + &riscv_isa_vendor_ext_list_thead, +#endif +}; + +const size_t riscv_isa_vendor_ext_list_size = ARRAY_SIZE(riscv_isa_vendor_ext_list); diff --git a/arch/riscv/kernel/vendor_extensions/Makefile b/arch/riscv/kernel/vendor_extensions/Makefile new file mode 100644 index 000000000000..3383066baaab --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0-only + +obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_THEAD) += thead.o diff --git a/arch/riscv/kernel/vendor_extensions/thead.c b/arch/riscv/kernel/vendor_extensions/thead.c new file mode 100644 index 000000000000..0934a2086473 --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions/thead.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <asm/cpufeature.h> +#include <asm/vendor_extensions.h> +#include <asm/vendor_extensions/thead.h> + +#include <linux/array_size.h> +#include <linux/types.h> + +/* All T-Head vendor extensions supported in Linux */ +const struct riscv_isa_ext_data riscv_isa_vendor_ext_thead[] = { + __RISCV_ISA_EXT_DATA(xtheadvector, RISCV_ISA_VENDOR_EXT_XTHEADVECTOR), +}; + +struct riscv_isa_vendor_ext_data_list riscv_isa_vendor_ext_list_thead = { + .ext_data_count = ARRAY_SIZE(riscv_isa_vendor_ext_thead), + .ext_data = riscv_isa_vendor_ext_thead, +};