Re: [PATCH v1 1/9] RISC-V: don't parse dt/acpi isa string to get rv32/rv64

Andrew Jones
2023-06-26T15:14:33Z

On Mon, Jun 26, 2023 at 12:19:39PM +0100, Conor Dooley wrote:
> From: Heiko Stuebner <heiko.stuebner@vrull.eu>
>
> When filling hwcap the kernel already expects the isa string to start with
> rv32 if CONFIG_32BIT and rv64 if CONFIG_64BIT.
>
> So when recreating the runtime isa-string we can also just go the other way
> to get the correct starting point for it.
>
> Signed-off-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
> Co-developed-by: Conor Dooley <conor.dooley@microchip.com>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
> arch/riscv/kernel/cpu.c | 16 ++++++++--------
> 1 file changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index a2fc952318e9..742bb42e7e86 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -253,13 +253,16 @@ static void print_isa_ext(struct seq_file *f)
> */
> static const char base_riscv_exts[13] = "imafdqcbkjpvh";
>
> -static void print_isa(struct seq_file *f, const char *isa)
> +static void print_isa(struct seq_file *f)
> {
> int i;
>
> seq_puts(f, "isa\t\t: ");
> - /* Print the rv[64/32] part */
> - seq_write(f, isa, 4);
> + if (IS_ENABLED(CONFIG_32BIT))
> + seq_write(f, "rv32", 4);
> + else
> + seq_write(f, "rv64", 4);
> +
> for (i = 0; i < sizeof(base_riscv_exts); i++) {
> if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a'))
> /* Print only enabled the base ISA extensions */
> @@ -316,15 +319,14 @@ static int c_show(struct seq_file *m, void *v)
> unsigned long cpu_id = (unsigned long)v - 1;
> struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
> struct device_node *node;
> - const char *compat, *isa;
> + const char *compat;
>
> seq_printf(m, "processor\t: %lu\n", cpu_id);
> seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id));
> + print_isa(m);
>
> if (acpi_disabled) {
> node = of_get_cpu_node(cpu_id, NULL);
> - if (!of_property_read_string(node, "riscv,isa", &isa))
> - print_isa(m, isa);
>
> print_mmu(m);
> if (!of_property_read_string(node, "compatible", &compat) &&
> @@ -333,8 +335,6 @@ static int c_show(struct seq_file *m, void *v)
>
> of_node_put(node);
> } else {
> - if (!acpi_get_riscv_isa(NULL, cpu_id, &isa))
> - print_isa(m, isa);
>

Extra blank line here to remove. Actually the whole 'else' can be removed
because the print_mmu() call can be brought up above the
'if (acpi_disabled)'

> print_mmu(m);
> }
> --
> 2.40.1
>

Otherwise,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew