Re: [PATCH v4 2/4] EDAC/mce_amd: Extract node id from MCA_IPID

Yazen Ghannam
2021-10-21T15:56:04Z

On Fri, Oct 15, 2021 at 12:23:58AM +0530, Naveen Krishna Chatradhi wrote:
> On SMCA banks of the GPU nodes, the node id information is
> available in register MCA_IPID[47:44](InstanceIdHi).
>
> Convert the hardware node ID to a value used by Linux
> where GPU nodes are sequencially after the CPU nodes.
>
> Co-developed-by: Muralidhara M K <muralimk@amd.com>
> Signed-off-by: Muralidhara M K <muralimk@amd.com>
> Signed-off-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
> Link: https://lkml.kernel.org/r/20210823185437.94417-3-nchatrad@amd.com
> ---
> Changes since v3:
> 1. Use APIs from amd_nb to identify the gpu_node_start_id and cpu_node_count.
> Which is required to map the hardware node id to node id enumerated by Linux.
>
> Changes since v2:
> 1. Modified subject and commit message
> 2. Added Reviewed by Yazen Ghannam
>
> Changes since v1:
> 1. Modified the commit message
> 2. rearranged the conditions before calling decode_dram_ecc()
>
> drivers/edac/mce_amd.c | 24 ++++++++++++++++++++++--
> 1 file changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
> index 67dbf4c31271..af6caa76adc7 100644
> --- a/drivers/edac/mce_amd.c
> +++ b/drivers/edac/mce_amd.c
> @@ -2,6 +2,7 @@
> #include <linux/module.h>
> #include <linux/slab.h>
>
> +#include <asm/amd_nb.h>
> #include <asm/cpu.h>
>
> #include "mce_amd.h"
> @@ -1072,8 +1073,27 @@ static void decode_smca_error(struct mce *m)
> if (xec < smca_mce_descs[bank_type].num_descs)
> pr_cont(", %s.\n", smca_mce_descs[bank_type].descs[xec]);
>
> - if (bank_type == SMCA_UMC && xec == 0 && decode_dram_ecc)
> - decode_dram_ecc(topology_die_id(m->extcpu), m);
> + if (xec == 0 && decode_dram_ecc) {
> + int node_id = 0;
> +
> + if (bank_type == SMCA_UMC) {
> + node_id = topology_die_id(m->extcpu);
> + } else if (bank_type == SMCA_UMC_V2) {
> + /*
> + * SMCA_UMC_V2 exists on GPU nodes, extract the node id
> + * from register MCA_IPID[47:44](InstanceIdHi).
> + * The InstanceIdHi field represents the instance ID of the GPU.
> + * Which needs to be mapped to a value used by Linux,
> + * where GPU nodes are simply numerically after the CPU nodes.
> + */
> + node_id = ((m->ipid >> 44) & 0xF) -
> + amd_gpu_node_start_id() + amd_cpu_node_count();
> + } else {
> + return;
> + }
> +
> + decode_dram_ecc(node_id, m);
> + }
> }
>
> static inline void amd_decode_err_code(u16 ec)
> --

This looks good to me.

Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>

Thanks,
Yazen