| Message ID | 1550864500-13652-7-git-send-email-atish.patra@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Various SMP related fixes | expand |
On Sat, Feb 23, 2019 at 1:11 AM Atish Patra <atish.patra@wdc.com> wrote: > > Currently, we set hwcap based on first valid hart from DT. This may not > be correct always as that hart might not be current booting cpu or may > have a different capability. > > Set hwcap as the capabilities supported by all possible harts with "okay" > status. > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > --- > arch/riscv/kernel/cpufeature.c | 41 ++++++++++++++++++++++------------------- > 1 file changed, 22 insertions(+), 19 deletions(-) > > diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c > index e7a4701f..bc29b010 100644 > --- a/arch/riscv/kernel/cpufeature.c > +++ b/arch/riscv/kernel/cpufeature.c > @@ -20,6 +20,7 @@ > #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 > @@ -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. */ > -- > 2.7.4 > Looks good to me. Reviewed-by: Anup Patel <anup@brainfault.org> Regards, Anup
On Fri, Feb 22, 2019 at 11:41:40AM -0800, Atish Patra wrote: > Currently, we set hwcap based on first valid hart from DT. This may not > be correct always as that hart might not be current booting cpu or may > have a different capability. > > Set hwcap as the capabilities supported by all possible harts with "okay" > status. > > Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Johan Hovold <johan@kernel.org>
s/comman/common/ in the subject. Andreas.
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index e7a4701f..bc29b010 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -20,6 +20,7 @@ #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 @@ -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. */
Currently, we set hwcap based on first valid hart from DT. This may not be correct always as that hart might not be current booting cpu or may have a different capability. Set hwcap as the capabilities supported by all possible harts with "okay" status. Signed-off-by: Atish Patra <atish.patra@wdc.com> --- arch/riscv/kernel/cpufeature.c | 41 ++++++++++++++++++++++------------------- 1 file changed, 22 insertions(+), 19 deletions(-)