Re: [PATCH v8 01/16] RISC-V: Don't fail in riscv_of_parent_hartid() for disabled HARTs

Atish Patra
2023-09-20T00:12:30Z

On Tue, Sep 12, 2023 at 10:50 AM Anup Patel <apatel@ventanamicro.com> wrote:
>
> The riscv_of_processor_hartid() used by riscv_of_parent_hartid() fails
> for HARTs disabled in the DT. This results in the following warning
> thrown by the RISC-V INTC driver for the E-core on SiFive boards:
>
> [ 0.000000] riscv-intc: unable to find hart id for /cpus/cpu@0/interrupt-controller
>
> The riscv_of_parent_hartid() is only expected to read the hartid from
> the DT so we should directly call of_get_cpu_hwid() instead of calling
> riscv_of_processor_hartid().
>
> Fixes: ad635e723e17 ("riscv: cpu: Add 64bit hartid support on RV64")
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
> arch/riscv/kernel/cpu.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index c17dacb1141c..157ace8b262c 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -125,13 +125,14 @@ int __init riscv_early_of_processor_hartid(struct device_node *node, unsigned lo
> */
> int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
> {
> - int rc;
> -
> for (; node; node = node->parent) {
> if (of_device_is_compatible(node, "riscv")) {
> - rc = riscv_of_processor_hartid(node, hartid);
> - if (!rc)
> - return 0;
> + *hartid = (unsigned long)of_get_cpu_hwid(node, 0);
> + if (*hartid == ~0UL) {
> + pr_warn("Found CPU without hart ID\n");
> + return -ENODEV;
> + }
> + return 0;
> }
> }
>
> --
> 2.34.1
>

LGTM.

Reviewed-by: Atish Patra <atishp@rivosinc.com>

--
Regards,
Atish