diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index e7a4701f0256..bc29b010b722 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -20,6 +20,7 @@ #include #include #include +#include unsigned long elf_hwcap __read_mostly; #ifdef CONFIG_FPU @@ -42,28 +43,30 @@ 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. - */ for_each_of_cpu_node(node) { - if (riscv_of_processor_hartid(node) >= 0) - break; - } - if (!node) { - pr_warn("Unable to find \"cpu\" devicetree entry\n"); - return; - } + unsigned long this_hwcap = 0; - if (of_property_read_string(node, "riscv,isa", &isa)) { - pr_warn("Unable to find \"riscv,isa\" devicetree entry\n"); - of_node_put(node); - return; - } - of_node_put(node); + if (riscv_of_processor_hartid(node) < 0) + continue; - for (i = 0; i < strlen(isa); ++i) - elf_hwcap |= isa2hwcap[(unsigned char)(isa[i])]; + 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) + 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. */