diff options
Diffstat (limited to 'arch/riscv/kernel/cpufeature.c')
| -rw-r--r-- | arch/riscv/kernel/cpufeature.c | 1245 |
1 files changed, 1197 insertions, 48 deletions
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index a6e369edbbd7..b057362f8fb5 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -1,80 +1,1229 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copied from arch/arm64/kernel/cpufeature.c * * Copyright (C) 2015 ARM Ltd. * Copyright (C) 2017 SiFive - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +#include <linux/acpi.h> +#include <linux/bitmap.h> +#include <linux/cpu.h> +#include <linux/cpuhotplug.h> +#include <linux/ctype.h> +#include <linux/log2.h> +#include <linux/memory.h> +#include <linux/module.h> #include <linux/of.h> -#include <asm/processor.h> +#include <asm/acpi.h> +#include <asm/alternative.h> +#include <asm/bugs.h> +#include <asm/cacheflush.h> +#include <asm/cpufeature.h> #include <asm/hwcap.h> +#include <asm/text-patching.h> +#include <asm/hwprobe.h> +#include <asm/processor.h> +#include <asm/sbi.h> +#include <asm/vector.h> +#include <asm/vendor_extensions.h> +#include <asm/vendor_extensions/thead.h> + +#define NUM_ALPHA_EXTS ('z' - 'a' + 1) + +static bool any_cpu_has_zicboz; +static bool any_cpu_has_zicbop; +static bool any_cpu_has_zicbom; unsigned long elf_hwcap __read_mostly; -#ifdef CONFIG_FPU -bool has_fpu __read_mostly; -#endif -void riscv_fill_hwcap(void) +/* Host ISA bitmap */ +static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __read_mostly; + +/* Per-cpu ISA extensions. */ +struct riscv_isainfo hart_isa[NR_CPUS]; + +u32 thead_vlenb_of; + +/** + * riscv_isa_extension_base() - Get base extension word + * + * @isa_bitmap: ISA bitmap to use + * Return: base extension word as unsigned long value + * + * NOTE: If isa_bitmap is NULL then Host ISA bitmap will be used. + */ +unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap) { - struct device_node *node = NULL; - const char *isa; - size_t i; - static unsigned long isa2hwcap[256] = {0}; + return !isa_bitmap ? riscv_isa[0] : isa_bitmap[0]; +} +EXPORT_SYMBOL_GPL(riscv_isa_extension_base); + +/** + * __riscv_isa_extension_available() - Check whether given extension + * is available or not + * + * @isa_bitmap: ISA bitmap to use + * @bit: bit position of the desired extension + * Return: true or false + * + * NOTE: If isa_bitmap is NULL then Host ISA bitmap will be used. + */ +bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, unsigned int bit) +{ + const unsigned long *bmap = (isa_bitmap) ? isa_bitmap : riscv_isa; + + if (bit >= RISCV_ISA_EXT_MAX) + return false; + + return test_bit(bit, bmap); +} +EXPORT_SYMBOL_GPL(__riscv_isa_extension_available); - isa2hwcap['i'] = isa2hwcap['I'] = COMPAT_HWCAP_ISA_I; - isa2hwcap['m'] = isa2hwcap['M'] = COMPAT_HWCAP_ISA_M; - isa2hwcap['a'] = isa2hwcap['A'] = COMPAT_HWCAP_ISA_A; - isa2hwcap['f'] = isa2hwcap['F'] = COMPAT_HWCAP_ISA_F; - isa2hwcap['d'] = isa2hwcap['D'] = COMPAT_HWCAP_ISA_D; - isa2hwcap['c'] = isa2hwcap['C'] = COMPAT_HWCAP_ISA_C; +static int riscv_ext_f_depends(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_f)) + return 0; - elf_hwcap = 0; + return -EPROBE_DEFER; +} + +static int riscv_ext_zicbom_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!riscv_cbom_block_size) { + pr_err("Zicbom detected in ISA string, disabling as no cbom-block-size found\n"); + return -EINVAL; + } + if (!is_power_of_2(riscv_cbom_block_size)) { + pr_err("Zicbom disabled as cbom-block-size present, but is not a power-of-2\n"); + return -EINVAL; + } + + any_cpu_has_zicbom = true; + return 0; +} + +static int riscv_ext_zicboz_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!riscv_cboz_block_size) { + pr_err("Zicboz detected in ISA string, disabling as no cboz-block-size found\n"); + return -EINVAL; + } + if (!is_power_of_2(riscv_cboz_block_size)) { + pr_err("Zicboz disabled as cboz-block-size present, but is not a power-of-2\n"); + return -EINVAL; + } + any_cpu_has_zicboz = true; + return 0; +} + +static int riscv_ext_zicbop_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!riscv_cbop_block_size) { + pr_err("Zicbop detected in ISA string, disabling as no cbop-block-size found\n"); + return -EINVAL; + } + if (!is_power_of_2(riscv_cbop_block_size)) { + pr_err("Zicbop disabled as cbop-block-size present, but is not a power-of-2\n"); + return -EINVAL; + } + any_cpu_has_zicbop = true; + return 0; +} + +static int riscv_ext_f_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!IS_ENABLED(CONFIG_FPU)) + return -EINVAL; /* - * We don't support running Linux on hertergenous ISA systems. For - * now, we just check the ISA of the first "okay" processor. + * Due to extension ordering, d is checked before f, so no deferral + * is required. */ - while ((node = of_find_node_by_type(node, "cpu"))) - if (riscv_of_processor_hartid(node) >= 0) + if (!__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_d)) { + pr_warn_once("This kernel does not support systems with F but not D\n"); + return -EINVAL; + } + + return 0; +} + +static int riscv_ext_d_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!IS_ENABLED(CONFIG_FPU)) + return -EINVAL; + + return 0; +} + +static int riscv_ext_vector_x_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!IS_ENABLED(CONFIG_RISCV_ISA_V)) + return -EINVAL; + + return 0; +} + +static int riscv_ext_vector_float_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!IS_ENABLED(CONFIG_RISCV_ISA_V)) + return -EINVAL; + + if (!IS_ENABLED(CONFIG_FPU)) + return -EINVAL; + + /* + * The kernel doesn't support systems that don't implement both of + * F and D, so if any of the vector extensions that do floating point + * are to be usable, both floating point extensions need to be usable. + * + * Since this function validates vector only, and v/Zve* are probed + * after f/d, there's no need for a deferral here. + */ + if (!__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_d)) + return -EINVAL; + + return 0; +} + +static int riscv_ext_vector_crypto_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!IS_ENABLED(CONFIG_RISCV_ISA_V)) + return -EINVAL; + + /* + * It isn't the kernel's job to check that the binding is correct, so + * it should be enough to check that any of the vector extensions are + * enabled, which in-turn means that vector is usable in this kernel + */ + if (!__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZVE32X)) + return -EPROBE_DEFER; + + return 0; +} + +static int riscv_ext_zca_depends(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA)) + return 0; + + return -EPROBE_DEFER; +} +static int riscv_ext_zcd_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA) && + __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_d)) + return 0; + + return -EPROBE_DEFER; +} + +static int riscv_ext_zcf_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (IS_ENABLED(CONFIG_64BIT)) + return -EINVAL; + + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA) && + __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_f)) + return 0; + + return -EPROBE_DEFER; +} + +static int riscv_vector_f_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (!IS_ENABLED(CONFIG_RISCV_ISA_V)) + return -EINVAL; + + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZVE32F)) + return 0; + + return -EPROBE_DEFER; +} + +static int riscv_ext_zvfbfwma_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZFBFMIN) && + __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZVFBFMIN)) + return 0; + + return -EPROBE_DEFER; +} + +static int riscv_ext_svadu_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + /* SVADE has already been detected, use SVADE only */ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_SVADE)) + return -EOPNOTSUPP; + + return 0; +} + +static const unsigned int riscv_a_exts[] = { + RISCV_ISA_EXT_ZAAMO, + RISCV_ISA_EXT_ZALRSC, +}; + +static const unsigned int riscv_zk_bundled_exts[] = { + RISCV_ISA_EXT_ZBKB, + RISCV_ISA_EXT_ZBKC, + RISCV_ISA_EXT_ZBKX, + RISCV_ISA_EXT_ZKND, + RISCV_ISA_EXT_ZKNE, + RISCV_ISA_EXT_ZKR, + RISCV_ISA_EXT_ZKT, +}; + +static const unsigned int riscv_zkn_bundled_exts[] = { + RISCV_ISA_EXT_ZBKB, + RISCV_ISA_EXT_ZBKC, + RISCV_ISA_EXT_ZBKX, + RISCV_ISA_EXT_ZKND, + RISCV_ISA_EXT_ZKNE, + RISCV_ISA_EXT_ZKNH, +}; + +static const unsigned int riscv_zks_bundled_exts[] = { + RISCV_ISA_EXT_ZBKB, + RISCV_ISA_EXT_ZBKC, + RISCV_ISA_EXT_ZKSED, + RISCV_ISA_EXT_ZKSH +}; + +#define RISCV_ISA_EXT_ZVKN \ + RISCV_ISA_EXT_ZVKNED, \ + RISCV_ISA_EXT_ZVKNHB, \ + RISCV_ISA_EXT_ZVKB, \ + RISCV_ISA_EXT_ZVKT + +static const unsigned int riscv_zvkn_bundled_exts[] = { + RISCV_ISA_EXT_ZVKN +}; + +static const unsigned int riscv_zvknc_bundled_exts[] = { + RISCV_ISA_EXT_ZVKN, + RISCV_ISA_EXT_ZVBC +}; + +static const unsigned int riscv_zvkng_bundled_exts[] = { + RISCV_ISA_EXT_ZVKN, + RISCV_ISA_EXT_ZVKG +}; + +#define RISCV_ISA_EXT_ZVKS \ + RISCV_ISA_EXT_ZVKSED, \ + RISCV_ISA_EXT_ZVKSH, \ + RISCV_ISA_EXT_ZVKB, \ + RISCV_ISA_EXT_ZVKT + +static const unsigned int riscv_zvks_bundled_exts[] = { + RISCV_ISA_EXT_ZVKS +}; + +static const unsigned int riscv_zvksc_bundled_exts[] = { + RISCV_ISA_EXT_ZVKS, + RISCV_ISA_EXT_ZVBC +}; + +static const unsigned int riscv_zvksg_bundled_exts[] = { + RISCV_ISA_EXT_ZVKS, + RISCV_ISA_EXT_ZVKG +}; + +static const unsigned int riscv_zvbb_exts[] = { + RISCV_ISA_EXT_ZVKB +}; + +#define RISCV_ISA_EXT_ZVE64F_IMPLY_LIST \ + RISCV_ISA_EXT_ZVE64X, \ + RISCV_ISA_EXT_ZVE32F, \ + RISCV_ISA_EXT_ZVE32X + +#define RISCV_ISA_EXT_ZVE64D_IMPLY_LIST \ + RISCV_ISA_EXT_ZVE64F, \ + RISCV_ISA_EXT_ZVE64F_IMPLY_LIST + +#define RISCV_ISA_EXT_V_IMPLY_LIST \ + RISCV_ISA_EXT_ZVE64D, \ + RISCV_ISA_EXT_ZVE64D_IMPLY_LIST + +static const unsigned int riscv_zve32f_exts[] = { + RISCV_ISA_EXT_ZVE32X +}; + +static const unsigned int riscv_zve64f_exts[] = { + RISCV_ISA_EXT_ZVE64F_IMPLY_LIST +}; + +static const unsigned int riscv_zve64d_exts[] = { + RISCV_ISA_EXT_ZVE64D_IMPLY_LIST +}; + +static const unsigned int riscv_v_exts[] = { + RISCV_ISA_EXT_V_IMPLY_LIST +}; + +static const unsigned int riscv_zve64x_exts[] = { + RISCV_ISA_EXT_ZVE32X, + RISCV_ISA_EXT_ZVE64X +}; + +/* + * While the [ms]envcfg CSRs were not defined until version 1.12 of the RISC-V + * privileged ISA, the existence of the CSRs is implied by any extension which + * specifies [ms]envcfg bit(s). Hence, we define a custom ISA extension for the + * existence of the CSR, and treat it as a subset of those other extensions. + */ +static const unsigned int riscv_xlinuxenvcfg_exts[] = { + RISCV_ISA_EXT_XLINUXENVCFG +}; + +/* + * Zc* spec states that: + * - C always implies Zca + * - C+F implies Zcf (RV32 only) + * - C+D implies Zcd + * + * These extensions will be enabled and then validated depending on the + * availability of F/D RV32. + */ +static const unsigned int riscv_c_exts[] = { + RISCV_ISA_EXT_ZCA, + RISCV_ISA_EXT_ZCF, + RISCV_ISA_EXT_ZCD, +}; + +/* + * The canonical order of ISA extension names in the ISA string is defined in + * chapter 27 of the unprivileged specification. + * + * Ordinarily, for in-kernel data structures, this order is unimportant but + * isa_ext_arr defines the order of the ISA string in /proc/cpuinfo. + * + * The specification uses vague wording, such as should, when it comes to + * ordering, so for our purposes the following rules apply: + * + * 1. All multi-letter extensions must be separated from other extensions by an + * underscore. + * + * 2. Additional standard extensions (starting with 'Z') must be sorted after + * single-letter extensions and before any higher-privileged extensions. + * + * 3. The first letter following the 'Z' conventionally indicates the most + * closely related alphabetical extension category, IMAFDQLCBKJTPVH. + * If multiple 'Z' extensions are named, they must be ordered first by + * category, then alphabetically within a category. + * + * 3. Standard supervisor-level extensions (starting with 'S') must be listed + * after standard unprivileged extensions. If multiple supervisor-level + * extensions are listed, they must be ordered alphabetically. + * + * 4. Standard machine-level extensions (starting with 'Zxm') must be listed + * after any lower-privileged, standard extensions. If multiple + * machine-level extensions are listed, they must be ordered + * alphabetically. + * + * 5. Non-standard extensions (starting with 'X') must be listed after all + * standard extensions. If multiple non-standard extensions are listed, they + * must be ordered alphabetically. + * + * An example string following the order is: + * rv64imadc_zifoo_zigoo_zafoo_sbar_scar_zxmbaz_xqux_xrux + * + * New entries to this struct should follow the ordering rules described above. + */ +const struct riscv_isa_ext_data riscv_isa_ext[] = { + __RISCV_ISA_EXT_DATA(i, RISCV_ISA_EXT_i), + __RISCV_ISA_EXT_DATA(m, RISCV_ISA_EXT_m), + __RISCV_ISA_EXT_SUPERSET(a, RISCV_ISA_EXT_a, riscv_a_exts), + __RISCV_ISA_EXT_DATA_VALIDATE(f, RISCV_ISA_EXT_f, riscv_ext_f_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(d, RISCV_ISA_EXT_d, riscv_ext_d_validate), + __RISCV_ISA_EXT_DATA(q, RISCV_ISA_EXT_q), + __RISCV_ISA_EXT_SUPERSET(c, RISCV_ISA_EXT_c, riscv_c_exts), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(v, RISCV_ISA_EXT_v, riscv_v_exts, riscv_ext_vector_float_validate), + __RISCV_ISA_EXT_DATA(h, RISCV_ISA_EXT_h), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zicbom, RISCV_ISA_EXT_ZICBOM, riscv_xlinuxenvcfg_exts, riscv_ext_zicbom_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zicbop, RISCV_ISA_EXT_ZICBOP, riscv_ext_zicbop_validate), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zicboz, RISCV_ISA_EXT_ZICBOZ, riscv_xlinuxenvcfg_exts, riscv_ext_zicboz_validate), + __RISCV_ISA_EXT_DATA(ziccrse, RISCV_ISA_EXT_ZICCRSE), + __RISCV_ISA_EXT_DATA(zicntr, RISCV_ISA_EXT_ZICNTR), + __RISCV_ISA_EXT_DATA(zicond, RISCV_ISA_EXT_ZICOND), + __RISCV_ISA_EXT_DATA(zicsr, RISCV_ISA_EXT_ZICSR), + __RISCV_ISA_EXT_DATA(zifencei, RISCV_ISA_EXT_ZIFENCEI), + __RISCV_ISA_EXT_DATA(zihintntl, RISCV_ISA_EXT_ZIHINTNTL), + __RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE), + __RISCV_ISA_EXT_DATA(zihpm, RISCV_ISA_EXT_ZIHPM), + __RISCV_ISA_EXT_DATA(zimop, RISCV_ISA_EXT_ZIMOP), + __RISCV_ISA_EXT_DATA(zaamo, RISCV_ISA_EXT_ZAAMO), + __RISCV_ISA_EXT_DATA(zabha, RISCV_ISA_EXT_ZABHA), + __RISCV_ISA_EXT_DATA(zacas, RISCV_ISA_EXT_ZACAS), + __RISCV_ISA_EXT_DATA(zalasr, RISCV_ISA_EXT_ZALASR), + __RISCV_ISA_EXT_DATA(zalrsc, RISCV_ISA_EXT_ZALRSC), + __RISCV_ISA_EXT_DATA(zawrs, RISCV_ISA_EXT_ZAWRS), + __RISCV_ISA_EXT_DATA_VALIDATE(zfa, RISCV_ISA_EXT_ZFA, riscv_ext_f_depends), + __RISCV_ISA_EXT_DATA_VALIDATE(zfbfmin, RISCV_ISA_EXT_ZFBFMIN, riscv_ext_f_depends), + __RISCV_ISA_EXT_DATA_VALIDATE(zfh, RISCV_ISA_EXT_ZFH, riscv_ext_f_depends), + __RISCV_ISA_EXT_DATA_VALIDATE(zfhmin, RISCV_ISA_EXT_ZFHMIN, riscv_ext_f_depends), + __RISCV_ISA_EXT_DATA(zca, RISCV_ISA_EXT_ZCA), + __RISCV_ISA_EXT_DATA_VALIDATE(zcb, RISCV_ISA_EXT_ZCB, riscv_ext_zca_depends), + __RISCV_ISA_EXT_DATA_VALIDATE(zcd, RISCV_ISA_EXT_ZCD, riscv_ext_zcd_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zcf, RISCV_ISA_EXT_ZCF, riscv_ext_zcf_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zcmop, RISCV_ISA_EXT_ZCMOP, riscv_ext_zca_depends), + __RISCV_ISA_EXT_DATA(zba, RISCV_ISA_EXT_ZBA), + __RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB), + __RISCV_ISA_EXT_DATA(zbc, RISCV_ISA_EXT_ZBC), + __RISCV_ISA_EXT_DATA(zbkb, RISCV_ISA_EXT_ZBKB), + __RISCV_ISA_EXT_DATA(zbkc, RISCV_ISA_EXT_ZBKC), + __RISCV_ISA_EXT_DATA(zbkx, RISCV_ISA_EXT_ZBKX), + __RISCV_ISA_EXT_DATA(zbs, RISCV_ISA_EXT_ZBS), + __RISCV_ISA_EXT_BUNDLE(zk, riscv_zk_bundled_exts), + __RISCV_ISA_EXT_BUNDLE(zkn, riscv_zkn_bundled_exts), + __RISCV_ISA_EXT_DATA(zknd, RISCV_ISA_EXT_ZKND), + __RISCV_ISA_EXT_DATA(zkne, RISCV_ISA_EXT_ZKNE), + __RISCV_ISA_EXT_DATA(zknh, RISCV_ISA_EXT_ZKNH), + __RISCV_ISA_EXT_DATA(zkr, RISCV_ISA_EXT_ZKR), + __RISCV_ISA_EXT_BUNDLE(zks, riscv_zks_bundled_exts), + __RISCV_ISA_EXT_DATA(zkt, RISCV_ISA_EXT_ZKT), + __RISCV_ISA_EXT_DATA(zksed, RISCV_ISA_EXT_ZKSED), + __RISCV_ISA_EXT_DATA(zksh, RISCV_ISA_EXT_ZKSH), + __RISCV_ISA_EXT_DATA(ztso, RISCV_ISA_EXT_ZTSO), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zvbb, RISCV_ISA_EXT_ZVBB, riscv_zvbb_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvbc, RISCV_ISA_EXT_ZVBC, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zve32f, RISCV_ISA_EXT_ZVE32F, riscv_zve32f_exts, riscv_ext_vector_float_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zve32x, RISCV_ISA_EXT_ZVE32X, riscv_ext_vector_x_validate), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zve64d, RISCV_ISA_EXT_ZVE64D, riscv_zve64d_exts, riscv_ext_vector_float_validate), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zve64f, RISCV_ISA_EXT_ZVE64F, riscv_zve64f_exts, riscv_ext_vector_float_validate), + __RISCV_ISA_EXT_SUPERSET_VALIDATE(zve64x, RISCV_ISA_EXT_ZVE64X, riscv_zve64x_exts, riscv_ext_vector_x_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvfbfmin, RISCV_ISA_EXT_ZVFBFMIN, riscv_vector_f_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvfbfwma, RISCV_ISA_EXT_ZVFBFWMA, riscv_ext_zvfbfwma_validate), + __RISCV_ISA_EXT_DATA(zvfh, RISCV_ISA_EXT_ZVFH), + __RISCV_ISA_EXT_DATA(zvfhmin, RISCV_ISA_EXT_ZVFHMIN), + __RISCV_ISA_EXT_DATA_VALIDATE(zvkb, RISCV_ISA_EXT_ZVKB, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvkg, RISCV_ISA_EXT_ZVKG, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_BUNDLE_VALIDATE(zvkn, riscv_zvkn_bundled_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_BUNDLE_VALIDATE(zvknc, riscv_zvknc_bundled_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvkned, RISCV_ISA_EXT_ZVKNED, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_BUNDLE_VALIDATE(zvkng, riscv_zvkng_bundled_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvknha, RISCV_ISA_EXT_ZVKNHA, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvknhb, RISCV_ISA_EXT_ZVKNHB, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_BUNDLE_VALIDATE(zvks, riscv_zvks_bundled_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_BUNDLE_VALIDATE(zvksc, riscv_zvksc_bundled_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvksed, RISCV_ISA_EXT_ZVKSED, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvksh, RISCV_ISA_EXT_ZVKSH, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_BUNDLE_VALIDATE(zvksg, riscv_zvksg_bundled_exts, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zvkt, RISCV_ISA_EXT_ZVKT, riscv_ext_vector_crypto_validate), + __RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA), + __RISCV_ISA_EXT_DATA(smmpm, RISCV_ISA_EXT_SMMPM), + __RISCV_ISA_EXT_SUPERSET(smnpm, RISCV_ISA_EXT_SMNPM, riscv_xlinuxenvcfg_exts), + __RISCV_ISA_EXT_DATA(smstateen, RISCV_ISA_EXT_SMSTATEEN), + __RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA), + __RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF), + __RISCV_ISA_EXT_SUPERSET(ssnpm, RISCV_ISA_EXT_SSNPM, riscv_xlinuxenvcfg_exts), + __RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC), + __RISCV_ISA_EXT_DATA(svade, RISCV_ISA_EXT_SVADE), + __RISCV_ISA_EXT_DATA_VALIDATE(svadu, RISCV_ISA_EXT_SVADU, riscv_ext_svadu_validate), + __RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL), + __RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT), + __RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT), + __RISCV_ISA_EXT_DATA(svrsw60t59b, RISCV_ISA_EXT_SVRSW60T59B), + __RISCV_ISA_EXT_DATA(svvptc, RISCV_ISA_EXT_SVVPTC), +}; + +const size_t riscv_isa_ext_count = ARRAY_SIZE(riscv_isa_ext); + +static void riscv_isa_set_ext(const struct riscv_isa_ext_data *ext, unsigned long *bitmap) +{ + if (ext->id != RISCV_ISA_EXT_INVALID) + set_bit(ext->id, bitmap); + + for (int i = 0; i < ext->subset_ext_size; i++) { + if (ext->subset_ext_ids[i] != RISCV_ISA_EXT_INVALID) + set_bit(ext->subset_ext_ids[i], bitmap); + } +} + +static const struct riscv_isa_ext_data *riscv_get_isa_ext_data(unsigned int ext_id) +{ + for (int i = 0; i < riscv_isa_ext_count; i++) { + if (riscv_isa_ext[i].id == ext_id) + return &riscv_isa_ext[i]; + } + + return NULL; +} + +/* + * "Resolve" a source ISA bitmap into one that matches kernel configuration as + * well as correct extension dependencies. Some extensions depends on specific + * kernel configuration to be usable (V needs CONFIG_RISCV_ISA_V for instance) + * and this function will actually validate all the extensions provided in + * source_isa into the resolved_isa based on extensions validate() callbacks. + */ +static void __init riscv_resolve_isa(unsigned long *source_isa, + unsigned long *resolved_isa, unsigned long *this_hwcap, + unsigned long *isa2hwcap) +{ + bool loop; + const struct riscv_isa_ext_data *ext; + DECLARE_BITMAP(prev_resolved_isa, RISCV_ISA_EXT_MAX); + int max_loop_count = riscv_isa_ext_count, ret; + unsigned int bit; + + do { + loop = false; + if (max_loop_count-- < 0) { + pr_err("Failed to reach a stable ISA state\n"); + return; + } + bitmap_copy(prev_resolved_isa, resolved_isa, RISCV_ISA_EXT_MAX); + for_each_set_bit(bit, source_isa, RISCV_ISA_EXT_MAX) { + ext = riscv_get_isa_ext_data(bit); + + if (ext && ext->validate) { + ret = ext->validate(ext, resolved_isa); + if (ret == -EPROBE_DEFER) { + loop = true; + continue; + } else if (ret) { + /* Disable the extension entirely */ + clear_bit(bit, source_isa); + continue; + } + } + + set_bit(bit, resolved_isa); + /* No need to keep it in source isa now that it is enabled */ + clear_bit(bit, source_isa); + + /* Single letter extensions get set in hwcap */ + if (bit < RISCV_ISA_EXT_BASE) + *this_hwcap |= isa2hwcap[bit]; + } + } while (loop && !bitmap_equal(prev_resolved_isa, resolved_isa, RISCV_ISA_EXT_MAX)); +} + +static void __init match_isa_ext(const char *name, const char *name_end, unsigned long *bitmap) +{ + for (int i = 0; i < riscv_isa_ext_count; i++) { + const struct riscv_isa_ext_data *ext = &riscv_isa_ext[i]; + + if ((name_end - name == strlen(ext->name)) && + !strncasecmp(name, ext->name, name_end - name)) { + riscv_isa_set_ext(ext, bitmap); + break; + } + } +} + +static void __init riscv_parse_isa_string(const char *isa, unsigned long *bitmap) +{ + /* + * For all possible cpus, we have already validated in + * the boot process that they at least contain "rv" and + * whichever of "32"/"64" this kernel supports, and so this + * section can be skipped. + */ + isa += 4; + + while (*isa) { + const char *ext = isa++; + const char *ext_end = isa; + bool 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). + * No need to set the bit in riscv_isa as 's' & 'u' are + * not valid ISA extensions. It works unless the first + * multi-letter extension in the ISA string begins with + * "Su" and is not prefixed with an underscore. + */ + if (ext[-1] != '_' && ext[1] == 'u') { + ++isa; + ext_err = true; + break; + } + fallthrough; + case 'S': + case 'z': + case 'Z': + /* + * Before attempting to parse the extension itself, 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. + * + * Next, as the extensions version is currently ignored, we + * eliminate that portion. This is done by parsing backwards from + * the end of the extension, removing any numbers. This may be a + * major or minor number however, so the process is repeated if a + * minor number was found. + * + * ext_end is intended to represent the first character *after* the + * name portion of an extension, but will be decremented to the last + * character itself while eliminating the extensions version number. + * A simple re-increment solves this problem. + */ + for (; *isa && *isa != '_'; ++isa) + if (unlikely(!isalnum(*isa))) + ext_err = true; + + ext_end = isa; + if (unlikely(ext_err)) + break; + + if (!isdigit(ext_end[-1])) + break; + + while (isdigit(*--ext_end)) + ; + + if (tolower(ext_end[0]) != 'p' || !isdigit(ext_end[-1])) { + ++ext_end; + break; + } + + while (isdigit(*--ext_end)) + ; + + ++ext_end; break; - if (!node) { - pr_warning("Unable to find \"cpu\" devicetree entry"); + default: + /* + * Things are a little easier for single-letter extensions, as they + * are parsed forwards. + * + * After checking that our starting position is valid, we need to + * ensure that, when isa was incremented at the start of the loop, + * that it arrived at the start of the next extension. + * + * If we are already on a non-digit, there is nothing to do. Either + * we have a multi-letter extension's _, or the start of an + * extension. + * + * Otherwise we have found the current extension's major version + * number. Parse past it, and a subsequent p/minor version number + * if present. The `p` extension must not appear immediately after + * a number, so there is no fear of missing it. + * + */ + if (unlikely(!isalpha(*ext))) { + ext_err = true; + break; + } + + if (!isdigit(*isa)) + break; + + while (isdigit(*++isa)) + ; + + if (tolower(*isa) != 'p') + break; + + if (!isdigit(*++isa)) { + --isa; + break; + } + + while (isdigit(*++isa)) + ; + + break; + } + + /* + * The parser expects that at the start of an iteration isa points to the + * first character of the next extension. As we stop parsing an extension + * on meeting a non-alphanumeric character, an extra increment is needed + * where the succeeding extension is a multi-letter prefixed with an "_". + */ + if (*isa == '_') + ++isa; + + if (unlikely(ext_err)) + continue; + + match_isa_ext(ext, ext_end, bitmap); + } +} + +static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap) +{ + struct device_node *node; + const char *isa; + int rc; + struct acpi_table_header *rhct; + acpi_status status; + unsigned int cpu; + u64 boot_vendorid; + u64 boot_archid; + + if (!acpi_disabled) { + status = acpi_get_table(ACPI_SIG_RHCT, 0, &rhct); + if (ACPI_FAILURE(status)) + return; + } + + boot_vendorid = riscv_get_mvendorid(); + boot_archid = riscv_get_marchid(); + + for_each_possible_cpu(cpu) { + struct riscv_isainfo *isainfo = &hart_isa[cpu]; + unsigned long this_hwcap = 0; + DECLARE_BITMAP(source_isa, RISCV_ISA_EXT_MAX) = { 0 }; + + if (acpi_disabled) { + node = of_cpu_device_node_get(cpu); + if (!node) { + pr_warn("Unable to find cpu node\n"); + continue; + } + + rc = of_property_read_string(node, "riscv,isa", &isa); + of_node_put(node); + if (rc) { + pr_warn("Unable to find \"riscv,isa\" devicetree entry\n"); + continue; + } + } else { + rc = acpi_get_riscv_isa(rhct, cpu, &isa); + if (rc < 0) { + pr_warn("Unable to get ISA for the hart - %d\n", cpu); + continue; + } + } + + riscv_parse_isa_string(isa, source_isa); + + /* + * These ones were as they were part of the base ISA when the + * port & dt-bindings were upstreamed, and so can be set + * unconditionally where `i` is in riscv,isa on DT systems. + */ + if (acpi_disabled) { + set_bit(RISCV_ISA_EXT_ZICSR, source_isa); + set_bit(RISCV_ISA_EXT_ZIFENCEI, source_isa); + set_bit(RISCV_ISA_EXT_ZICNTR, source_isa); + set_bit(RISCV_ISA_EXT_ZIHPM, source_isa); + } + + /* + * "V" in ISA strings is ambiguous in practice: it should mean + * just the standard V-1.0 but vendors aren't well behaved. + * Many vendors with T-Head CPU cores which implement the 0.7.1 + * version of the vector specification put "v" into their DTs. + * CPU cores with the ratified spec will contain non-zero + * marchid. + */ + if (acpi_disabled && boot_vendorid == THEAD_VENDOR_ID && boot_archid == 0x0) { + this_hwcap &= ~isa2hwcap[RISCV_ISA_EXT_v]; + clear_bit(RISCV_ISA_EXT_v, source_isa); + } + + riscv_resolve_isa(source_isa, isainfo->isa, &this_hwcap, isa2hwcap); + + /* + * All "okay" hart should have same isa. Set HWCAP based on + * common capabilities of every "okay" hart, in case they don't + * have. + */ + if (elf_hwcap) + elf_hwcap &= this_hwcap; + else + elf_hwcap = this_hwcap; + + if (bitmap_empty(riscv_isa, RISCV_ISA_EXT_MAX)) + bitmap_copy(riscv_isa, isainfo->isa, RISCV_ISA_EXT_MAX); + else + bitmap_and(riscv_isa, riscv_isa, isainfo->isa, RISCV_ISA_EXT_MAX); + } + + if (!acpi_disabled && rhct) + 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); + } } +} - if (of_property_read_string(node, "riscv,isa", &isa)) { - pr_warning("Unable to find \"riscv,isa\" devicetree entry"); - of_node_put(node); +/* + * Populate all_harts_isa_bitmap for each vendor with all of the extensions that + * are shared across CPUs for that vendor. + */ +static void __init riscv_fill_vendor_ext_list(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]; + + if (!ext_list->is_initialized) { + bitmap_copy(ext_list->all_harts_isa_bitmap.isa, + ext_list->per_hart_isa_bitmap[cpu].isa, + RISCV_ISA_VENDOR_EXT_MAX); + ext_list->is_initialized = true; + } 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); + } } - of_node_put(node); +} + +static int has_thead_homogeneous_vlenb(void) +{ + int cpu; + u32 prev_vlenb = 0; + u32 vlenb = 0; + + /* Ignore thead,vlenb property if xtheadvector is not enabled in the kernel */ + if (!IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR)) + return 0; + + for_each_possible_cpu(cpu) { + struct device_node *cpu_node; + + cpu_node = of_cpu_device_node_get(cpu); + if (!cpu_node) { + pr_warn("Unable to find cpu node\n"); + return -ENOENT; + } + + if (of_property_read_u32(cpu_node, "thead,vlenb", &vlenb)) { + of_node_put(cpu_node); - for (i = 0; i < strlen(isa); ++i) - elf_hwcap |= isa2hwcap[(unsigned char)(isa[i])]; + if (prev_vlenb) + return -ENOENT; + continue; + } - /* We don't support systems with F but without D, so mask those out - * here. */ + if (prev_vlenb && vlenb != prev_vlenb) { + of_node_put(cpu_node); + return -ENOENT; + } + + prev_vlenb = vlenb; + of_node_put(cpu_node); + } + + thead_vlenb_of = vlenb; + return 0; +} + +static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap) +{ + unsigned int cpu; + bool mitigated; + + for_each_possible_cpu(cpu) { + unsigned long this_hwcap = 0; + struct device_node *cpu_node; + struct riscv_isainfo *isainfo = &hart_isa[cpu]; + DECLARE_BITMAP(source_isa, RISCV_ISA_EXT_MAX) = { 0 }; + + cpu_node = of_cpu_device_node_get(cpu); + if (!cpu_node) { + pr_warn("Unable to find cpu node\n"); + continue; + } + + if (!of_property_present(cpu_node, "riscv,isa-extensions")) { + of_node_put(cpu_node); + continue; + } + + for (int i = 0; i < riscv_isa_ext_count; i++) { + const struct riscv_isa_ext_data *ext = &riscv_isa_ext[i]; + + if (of_property_match_string(cpu_node, "riscv,isa-extensions", + ext->property) < 0) + continue; + + riscv_isa_set_ext(ext, source_isa); + } + + riscv_resolve_isa(source_isa, isainfo->isa, &this_hwcap, isa2hwcap); + riscv_fill_cpu_vendor_ext(cpu_node, cpu); + + of_node_put(cpu_node); + + /* + * All "okay" harts should have same isa. Set HWCAP based on + * common capabilities of every "okay" hart, in case they don't. + */ + if (elf_hwcap) + elf_hwcap &= this_hwcap; + else + elf_hwcap = this_hwcap; + + if (bitmap_empty(riscv_isa, RISCV_ISA_EXT_MAX)) + 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); + } + + /* + * Execute ghostwrite mitigation immediately after detecting extensions + * to disable xtheadvector if necessary. + */ + mitigated = ghostwrite_enable_mitigation(); + + if (!mitigated && has_xtheadvector_no_alternatives() && has_thead_homogeneous_vlenb() < 0) { + pr_warn("Unsupported heterogeneous vlenb detected, vector extension disabled.\n"); + disable_xtheadvector(); + } + + if (bitmap_empty(riscv_isa, RISCV_ISA_EXT_MAX)) + return -ENOENT; + + return 0; +} + +#ifdef CONFIG_RISCV_ISA_FALLBACK +bool __initdata riscv_isa_fallback = true; +#else +bool __initdata riscv_isa_fallback; +static int __init riscv_isa_fallback_setup(char *__unused) +{ + riscv_isa_fallback = true; + return 1; +} +early_param("riscv_isa_fallback", riscv_isa_fallback_setup); +#endif + +void __init riscv_fill_hwcap(void) +{ + char print_str[NUM_ALPHA_EXTS + 1]; + unsigned long isa2hwcap[26] = {0}; + int i, j; + + isa2hwcap['i' - 'a'] = COMPAT_HWCAP_ISA_I; + isa2hwcap['m' - 'a'] = COMPAT_HWCAP_ISA_M; + isa2hwcap['a' - 'a'] = COMPAT_HWCAP_ISA_A; + isa2hwcap['f' - 'a'] = COMPAT_HWCAP_ISA_F; + isa2hwcap['d' - 'a'] = COMPAT_HWCAP_ISA_D; + isa2hwcap['c' - 'a'] = COMPAT_HWCAP_ISA_C; + isa2hwcap['v' - 'a'] = COMPAT_HWCAP_ISA_V; + + if (!acpi_disabled) { + riscv_fill_hwcap_from_isa_string(isa2hwcap); + } else { + int ret = riscv_fill_hwcap_from_ext_list(isa2hwcap); + + if (ret && riscv_isa_fallback) { + pr_info("Falling back to deprecated \"riscv,isa\"\n"); + riscv_fill_hwcap_from_isa_string(isa2hwcap); + } + } + + /* + * We don't support systems with F but without D, so mask those out + * here. + */ if ((elf_hwcap & COMPAT_HWCAP_ISA_F) && !(elf_hwcap & COMPAT_HWCAP_ISA_D)) { - pr_info("This kernel does not support systems with F but not D"); + pr_info("This kernel does not support systems with F but not D\n"); elf_hwcap &= ~COMPAT_HWCAP_ISA_F; } - pr_info("elf_hwcap is 0x%lx", elf_hwcap); + if (__riscv_isa_extension_available(NULL, RISCV_ISA_EXT_ZVE32X) || + has_xtheadvector_no_alternatives()) { + /* + * This cannot fail when called on the boot hart + */ + riscv_v_setup_vsize(); + } -#ifdef CONFIG_FPU - if (elf_hwcap & (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D)) - has_fpu = true; -#endif + memset(print_str, 0, sizeof(print_str)); + for (i = 0, j = 0; i < NUM_ALPHA_EXTS; i++) + if (riscv_isa[0] & BIT_MASK(i)) + print_str[j++] = (char)('a' + i); + pr_info("riscv: base ISA extensions %s\n", print_str); + + memset(print_str, 0, sizeof(print_str)); + for (i = 0, j = 0; i < NUM_ALPHA_EXTS; i++) + if (elf_hwcap & BIT_MASK(i)) + print_str[j++] = (char)('a' + i); + pr_info("riscv: ELF capabilities %s\n", print_str); } + +unsigned long riscv_get_elf_hwcap(void) +{ + unsigned long hwcap; + + hwcap = (elf_hwcap & ((1UL << RISCV_ISA_EXT_BASE) - 1)); + + if (!riscv_v_vstate_ctrl_user_allowed()) + hwcap &= ~COMPAT_HWCAP_ISA_V; + + return hwcap; +} + +void __init riscv_user_isa_enable(void) +{ + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_ZICBOZ)) + current->thread.envcfg |= ENVCFG_CBZE; + else if (any_cpu_has_zicboz) + pr_warn("Zicboz disabled as it is unavailable on some harts\n"); + + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_ZICBOM)) + current->thread.envcfg |= ENVCFG_CBCFE; + else if (any_cpu_has_zicbom) + pr_warn("Zicbom disabled as it is unavailable on some harts\n"); + + if (!riscv_has_extension_unlikely(RISCV_ISA_EXT_ZICBOP) && + any_cpu_has_zicbop) + pr_warn("Zicbop disabled as it is unavailable on some harts\n"); +} + +#ifdef CONFIG_RISCV_ALTERNATIVE +/* + * Alternative patch sites consider 48 bits when determining when to patch + * the old instruction sequence with the new. These bits are broken into a + * 16-bit vendor ID and a 32-bit patch ID. A non-zero vendor ID means the + * patch site is for an erratum, identified by the 32-bit patch ID. When + * the vendor ID is zero, the patch site is for a cpufeature. cpufeatures + * further break down patch ID into two 16-bit numbers. The lower 16 bits + * are the cpufeature ID and the upper 16 bits are used for a value specific + * to the cpufeature and patch site. If the upper 16 bits are zero, then it + * implies no specific value is specified. cpufeatures that want to control + * patching on a per-site basis will provide non-zero values and implement + * checks here. The checks return true when patching should be done, and + * false otherwise. + */ +static bool riscv_cpufeature_patch_check(u16 id, u16 value) +{ + if (!value) + return true; + + switch (id) { + case RISCV_ISA_EXT_ZICBOZ: + /* + * Zicboz alternative applications provide the maximum + * supported block size order, or zero when it doesn't + * matter. If the current block size exceeds the maximum, + * then the alternative cannot be applied. + */ + return riscv_cboz_block_size <= (1U << value); + } + + return false; +} + +void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin, + struct alt_entry *end, + unsigned int stage) +{ + struct alt_entry *alt; + void *oldptr, *altptr; + u16 id, value, vendor; + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + return; + + for (alt = begin; alt < end; alt++) { + id = PATCH_ID_CPUFEATURE_ID(alt->patch_id); + vendor = PATCH_ID_CPUFEATURE_ID(alt->vendor_id); + + /* + * Any alternative with a patch_id that is less than + * RISCV_ISA_EXT_MAX is interpreted as a standard extension. + * + * Any alternative with patch_id that is greater than or equal + * to RISCV_VENDOR_EXT_ALTERNATIVES_BASE is interpreted as a + * vendor extension. + */ + if (id < RISCV_ISA_EXT_MAX) { + /* + * This patch should be treated as errata so skip + * processing here. + */ + if (alt->vendor_id != 0) + continue; + + if (!__riscv_isa_extension_available(NULL, id)) + continue; + + value = PATCH_ID_CPUFEATURE_VALUE(alt->patch_id); + if (!riscv_cpufeature_patch_check(id, value)) + continue; + } else if (id >= RISCV_VENDOR_EXT_ALTERNATIVES_BASE) { + if (!__riscv_isa_vendor_extension_available(VENDOR_EXT_ALL_CPUS, vendor, + id - RISCV_VENDOR_EXT_ALTERNATIVES_BASE)) + continue; + } else { + WARN(1, "This extension id:%d is not in ISA extension list", id); + continue; + } + + oldptr = ALT_OLD_PTR(alt); + altptr = ALT_ALT_PTR(alt); + + mutex_lock(&text_mutex); + patch_text_nosync(oldptr, altptr, alt->alt_len); + riscv_alternative_fix_offsets(oldptr, alt->alt_len, oldptr - altptr); + mutex_unlock(&text_mutex); + } +} +#endif |