diff options
Diffstat (limited to 'arch/riscv/kernel/cpufeature.c')
| -rw-r--r-- | arch/riscv/kernel/cpufeature.c | 61 |
1 files changed, 27 insertions, 34 deletions
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index a6e369edbbd7..b1ade9a49347 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -1,25 +1,15 @@ +// 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/of.h> #include <asm/processor.h> #include <asm/hwcap.h> +#include <asm/smp.h> unsigned long elf_hwcap __read_mostly; #ifdef CONFIG_FPU @@ -28,7 +18,7 @@ bool has_fpu __read_mostly; void riscv_fill_hwcap(void) { - struct device_node *node = NULL; + struct device_node *node; const char *isa; size_t i; static unsigned long isa2hwcap[256] = {0}; @@ -42,36 +32,39 @@ void riscv_fill_hwcap(void) elf_hwcap = 0; - /* - * We don't support running Linux on hertergenous ISA systems. For - * now, we just check the ISA of the first "okay" processor. - */ - while ((node = of_find_node_by_type(node, "cpu"))) - if (riscv_of_processor_hartid(node) >= 0) - break; - if (!node) { - pr_warning("Unable to find \"cpu\" devicetree entry"); - return; - } + for_each_of_cpu_node(node) { + unsigned long this_hwcap = 0; - if (of_property_read_string(node, "riscv,isa", &isa)) { - pr_warning("Unable to find \"riscv,isa\" devicetree entry"); - of_node_put(node); - return; - } - of_node_put(node); + if (riscv_of_processor_hartid(node) < 0) + continue; + + if (of_property_read_string(node, "riscv,isa", &isa)) { + pr_warn("Unable to find \"riscv,isa\" devicetree entry\n"); + continue; + } - for (i = 0; i < strlen(isa); ++i) - elf_hwcap |= isa2hwcap[(unsigned char)(isa[i])]; + for (i = 0; i < strlen(isa); ++i) + this_hwcap |= isa2hwcap[(unsigned char)(isa[i])]; + + /* + * 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; + } /* 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); + pr_info("elf_hwcap is 0x%lx\n", elf_hwcap); #ifdef CONFIG_FPU if (elf_hwcap & (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D)) |