Create a private namespace for each vendor above 0x8000. During the probing of hardware capabilities, the vendorid of each hart is used to resolve the vendor extension compatibility.
Signed-off-by: Charlie Jenkins charlie@rivosinc.com --- arch/riscv/include/asm/cpufeature.h | 28 +++++ arch/riscv/include/asm/hwcap.h | 23 ++++ arch/riscv/include/asm/vendor_extensions.h | 15 +++ arch/riscv/kernel/Makefile | 2 + arch/riscv/kernel/cpufeature.c | 136 +++++++++++++++------ arch/riscv/kernel/vendor_extensions.c | 32 +++++ arch/riscv/kernel/vendor_extensions/Makefile | 3 + .../kernel/vendor_extensions/thead_extensions.c | 13 ++ 8 files changed, 214 insertions(+), 38 deletions(-)
diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h index 347805446151..50fa174cccb9 100644 --- a/arch/riscv/include/asm/cpufeature.h +++ b/arch/riscv/include/asm/cpufeature.h @@ -26,13 +26,41 @@ struct riscv_isainfo { DECLARE_BITMAP(isa, RISCV_ISA_EXT_MAX); };
+struct riscv_isavendorinfo { + DECLARE_BITMAP(isa, RISCV_ISA_VENDOR_EXT_SIZE); +}; + DECLARE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
/* Per-cpu ISA extensions. */ extern struct riscv_isainfo hart_isa[NR_CPUS];
+/* Per-cpu ISA vendor extensions. */ +extern struct riscv_isainfo hart_isa_vendor[NR_CPUS]; + +/* Vendor that is associated with hart_isa_vendor */ +extern unsigned long hart_isa_vendorid; + 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/hwcap.h b/arch/riscv/include/asm/hwcap.h index e17d0078a651..38157be5becd 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -87,6 +87,29 @@ #define RISCV_ISA_EXT_MAX 128 #define RISCV_ISA_EXT_INVALID U32_MAX
+/* + * These macros represent the logical IDs of each vendor RISC-V ISA extension + * and are used in each vendor ISA bitmap. The logical IDs start from + * RISCV_ISA_VENDOR_EXT_BASE, which allows the 0-0x7999 range to be + * reserved for non-vendor extensions. The maximum, RISCV_ISA_VENDOR_EXT_MAX, + * is defined in order to allocate the bitmap and may be increased when + * necessary. + * + * Values are expected to overlap between vendors. + * + * New extensions should just be added to the bottom of the respective vendor, + * rather than added alphabetically, in order to avoid unnecessary shuffling. + * + */ +#define RISCV_ISA_VENDOR_EXT_BASE 0x8000 + +/* THead Vendor Extensions */ +#define RISCV_ISA_VENDOR_EXT_XTHEADVECTOR 0x8000 + +#define RISCV_ISA_VENDOR_EXT_MAX 0x8080 +#define RISCV_ISA_VENDOR_EXT_SIZE (RISCV_ISA_VENDOR_EXT_MAX - RISCV_ISA_VENDOR_EXT_BASE) +#define RISCV_ISA_VENDOR_EXT_INVALID U32_MAX + #ifdef CONFIG_RISCV_M_MODE #define RISCV_ISA_EXT_SxAIA RISCV_ISA_EXT_SMAIA #else diff --git a/arch/riscv/include/asm/vendor_extensions.h b/arch/riscv/include/asm/vendor_extensions.h new file mode 100644 index 000000000000..0a1955e1c900 --- /dev/null +++ b/arch/riscv/include/asm/vendor_extensions.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright 2024 Rivos, Inc + */ + +#ifndef _ASM_VENDOR_EXTENSIONS_H +#define _ASM_VENDOR_EXTENSIONS_H + +extern const struct riscv_isa_ext_data riscv_isa_vendor_ext_thead[]; +extern const size_t riscv_isa_vendor_ext_count_thead; + +bool get_isa_vendor_ext(unsigned long vendorid, const struct riscv_isa_ext_data **isa_vendor_ext, + size_t *count); + +#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 6dff7bb1db3f..d7a33e017a15 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)
@@ -32,9 +33,18 @@ unsigned long elf_hwcap __read_mostly; /* Host ISA bitmap */ static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __read_mostly;
+/* Host ISA vendor bitmap */ +static DECLARE_BITMAP(riscv_isa_vendor, RISCV_ISA_VENDOR_EXT_SIZE) __read_mostly; + /* Per-cpu ISA extensions. */ struct riscv_isainfo hart_isa[NR_CPUS];
+/* Per-cpu ISA vendor extensions. */ +struct riscv_isainfo hart_isa_vendor[NR_CPUS]; + +/* Vendor that is associated with hart_isa_vendor */ +unsigned long hart_isa_vendorid; + /** * riscv_isa_extension_base() - Get base extension word * @@ -100,24 +110,6 @@ 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, @@ -351,6 +343,14 @@ 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': + pr_warn("Vendor extensions are ignored in riscv,isa. Use riscv,isa-extensions instead."); + /* + * In canonical order, the remaining extensions in the + * isa string will be vendor extensions so exit. + */ + break; case 's': /* * Workaround for invalid single-letter 's' & 'u' (QEMU). @@ -366,8 +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': /* @@ -578,15 +576,54 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap) acpi_put_table((struct acpi_table_header *)rhct); }
+static void __init riscv_add_cpu_ext(struct device_node *cpu_node, + unsigned long *this_hwcap, + unsigned long *isa2hwcap, + const struct riscv_isa_ext_data *riscv_isa_ext_data, + struct riscv_isainfo *isainfo, + unsigned int id_offset, + size_t riscv_isa_ext_count) +{ + for (int i = 0; i < riscv_isa_ext_count; i++) { + const struct riscv_isa_ext_data ext = riscv_isa_ext_data[i]; + + if (of_property_match_string(cpu_node, "riscv,isa-extensions", + ext.property) < 0) + continue; + + if (ext.subset_ext_size) { + for (int j = 0; j < ext.subset_ext_size; j++) { + if (riscv_isa_extension_check(ext.subset_ext_ids[j])) + set_bit(ext.subset_ext_ids[j] - id_offset, isainfo->isa); + } + } + + if (riscv_isa_extension_check(ext.id)) { + set_bit(ext.id - id_offset, isainfo->isa); + + /* Only single letter extensions get set in hwcap */ + if (strnlen(ext.name, 2) == 1) + *this_hwcap |= isa2hwcap[ext.id]; + } + } +} + static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap) { unsigned int cpu; + u64 boot_vendorid, vendorid;
for_each_possible_cpu(cpu) { unsigned long this_hwcap = 0; struct device_node *cpu_node; struct riscv_isainfo *isainfo = &hart_isa[cpu];
+ struct riscv_isainfo *isavendorinfo = &hart_isa_vendor[cpu]; + size_t riscv_isa_vendor_ext_count; + const struct riscv_isa_ext_data *riscv_isa_vendor_ext; + u64 this_vendorid; + bool found_vendor; + cpu_node = of_cpu_device_node_get(cpu); if (!cpu_node) { pr_warn("Unable to find cpu node\n"); @@ -598,28 +635,32 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap) continue; }
- for (int i = 0; i < riscv_isa_ext_count; i++) { - const struct riscv_isa_ext_data *ext = &riscv_isa_ext[i]; + riscv_add_cpu_ext(cpu_node, &this_hwcap, isa2hwcap, + riscv_isa_ext, isainfo, 0, + riscv_isa_ext_count);
- if (of_property_match_string(cpu_node, "riscv,isa-extensions", - ext->property) < 0) - continue; + if (of_property_read_u64(cpu_node, "riscv,vendorid", &this_vendorid) < 0) { + pr_warn("Unable to find "riscv,vendorid" devicetree entry, using boot hart mvendorid instead\n"); + if (boot_vendorid == -1) + boot_vendorid = riscv_get_mvendorid(); + this_vendorid = boot_vendorid; + } else { + struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu);
- if (ext->subset_ext_size) { - for (int j = 0; j < ext->subset_ext_size; j++) { - if (riscv_isa_extension_check(ext->subset_ext_ids[j])) - set_bit(ext->subset_ext_ids[j], isainfo->isa); - } - } + ci->mvendorid = this_vendorid; + }
- if (riscv_isa_extension_check(ext->id)) { - set_bit(ext->id, isainfo->isa); + found_vendor = get_isa_vendor_ext(this_vendorid, + &riscv_isa_vendor_ext, + &riscv_isa_vendor_ext_count);
- /* Only single letter extensions get set in hwcap */ - if (strnlen(riscv_isa_ext[i].name, 2) == 1) - this_hwcap |= isa2hwcap[riscv_isa_ext[i].id]; - } - } + if (found_vendor) + riscv_add_cpu_ext(cpu_node, &this_hwcap, isa2hwcap, + riscv_isa_vendor_ext, isavendorinfo, + RISCV_ISA_VENDOR_EXT_BASE, riscv_isa_vendor_ext_count); + else + pr_warn("No associated vendor extensions with vendor id: %llx\n", + vendorid);
of_node_put(cpu_node);
@@ -636,8 +677,27 @@ 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); + + /* + * All harts must have the same vendorid to have compatible + * vendor extensions. + */ + if (bitmap_empty(riscv_isa_vendor, RISCV_ISA_VENDOR_EXT_SIZE)) { + vendorid = this_vendorid; + bitmap_copy(riscv_isa_vendor, isavendorinfo->isa, + RISCV_ISA_VENDOR_EXT_SIZE); + } else if (vendorid != this_vendorid) { + vendorid = -1ULL; + bitmap_clear(riscv_isa_vendor, 0, + RISCV_ISA_VENDOR_EXT_SIZE); + } else { + bitmap_and(riscv_isa_vendor, riscv_isa_vendor, + isavendorinfo->isa, RISCV_ISA_VENDOR_EXT_SIZE); + } }
+ hart_isa_vendorid = vendorid; + if (bitmap_empty(riscv_isa, RISCV_ISA_EXT_MAX)) return -ENOENT;
diff --git a/arch/riscv/kernel/vendor_extensions.c b/arch/riscv/kernel/vendor_extensions.c new file mode 100644 index 000000000000..3a8a6c6dd34e --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2024 Rivos, Inc + */ + +#include <asm/cpufeature.h> +#include <asm/vendorid_list.h> +#include <asm/vendor_extensions.h> + +#include <linux/init.h> +#include <linux/types.h> + +bool __init get_isa_vendor_ext(unsigned long vendorid, + const struct riscv_isa_ext_data **isa_vendor_ext, + size_t *count) +{ + bool found_vendor = true; + + switch (vendorid) { + case THEAD_VENDOR_ID: + *isa_vendor_ext = riscv_isa_vendor_ext_thead; + *count = riscv_isa_vendor_ext_count_thead; + break; + default: + *isa_vendor_ext = NULL; + *count = 0; + found_vendor = false; + break; + } + + return found_vendor; +} diff --git a/arch/riscv/kernel/vendor_extensions/Makefile b/arch/riscv/kernel/vendor_extensions/Makefile new file mode 100644 index 000000000000..dcf3de8d4658 --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0-only + +obj-y += thead_extensions.o diff --git a/arch/riscv/kernel/vendor_extensions/thead_extensions.c b/arch/riscv/kernel/vendor_extensions/thead_extensions.c new file mode 100644 index 000000000000..7ac934b1f54c --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions/thead_extensions.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <asm/cpufeature.h> +#include <asm/hwcap.h> +#include <asm/vendor_extensions.h> + +#include <linux/array_size.h> + +const struct riscv_isa_ext_data riscv_isa_vendor_ext_thead[] = { + __RISCV_ISA_EXT_DATA(xtheadvector, RISCV_ISA_VENDOR_EXT_XTHEADVECTOR), +}; + +const size_t riscv_isa_vendor_ext_count_thead = ARRAY_SIZE(riscv_isa_vendor_ext_thead);