Re: [PATCH 2/2] hwmon: (dimmtemp) Add Sapphire Rappids support

From: Guenter Roeck
Date: Mon Jul 10 2023 - 14:48:59 EST


On Mon, Jul 10, 2023 at 06:47:04PM +0200, Naresh Solanki wrote:
> From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
>
> This patch extends the functionality of the hwmon (dimmtemp) to include
> support for Sapphire Rappids platform.
>
> Sapphire Rappids can accommodate up to 8 CPUs, each with 16 DIMMs. To
> accommodate this configuration, the maximum supported DIMM count is
> increased, and the corresponding Sapphire Rappids ID and threshold code
> are added.
>
> The patch has been tested on a 4S system with 64 DIMMs installed.
> Default thresholds are utilized for Sapphire Rappids, as accessing the
> threshold requires accessing the UBOX device on Uncore bus 0, which can
> only be achieved using MSR access. The non-PCI-compliant MMIO BARs are
> not available for this purpose.
>
> Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>

Does this patch depend on the other patch, the one introducing
Sapphire Rappids to peci/cputemp ?

Guenter

> ---
> drivers/hwmon/peci/dimmtemp.c | 24 +++++++++++++++++++++++-
> 1 file changed, 23 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwmon/peci/dimmtemp.c b/drivers/hwmon/peci/dimmtemp.c
> index ce89da3937a0..ea4ac5a023cf 100644
> --- a/drivers/hwmon/peci/dimmtemp.c
> +++ b/drivers/hwmon/peci/dimmtemp.c
> @@ -30,8 +30,10 @@
> #define DIMM_IDX_MAX_ON_ICX 2
> #define CHAN_RANK_MAX_ON_ICXD 4
> #define DIMM_IDX_MAX_ON_ICXD 2
> +#define CHAN_RANK_MAX_ON_SPR 128
> +#define DIMM_IDX_MAX_ON_SPR 2
>
> -#define CHAN_RANK_MAX CHAN_RANK_MAX_ON_HSX
> +#define CHAN_RANK_MAX CHAN_RANK_MAX_ON_SPR
> #define DIMM_IDX_MAX DIMM_IDX_MAX_ON_HSX
> #define DIMM_NUMS_MAX (CHAN_RANK_MAX * DIMM_IDX_MAX)
>
> @@ -534,6 +536,15 @@ read_thresholds_icx(struct peci_dimmtemp *priv, int dimm_order, int chan_rank, u
> return 0;
> }
>
> +static int
> +read_thresholds_spr(struct peci_dimmtemp *priv, int dimm_order, int chan_rank, u32 *data)
> +{
> + /* Use defaults */
> + *data = (95 << 16) | (90 << 8);
> +
> + return 0;
> +}
> +
> static const struct dimm_info dimm_hsx = {
> .chan_rank_max = CHAN_RANK_MAX_ON_HSX,
> .dimm_idx_max = DIMM_IDX_MAX_ON_HSX,
> @@ -576,6 +587,13 @@ static const struct dimm_info dimm_icxd = {
> .read_thresholds = &read_thresholds_icx,
> };
>
> +static const struct dimm_info dimm_spr = {
> + .chan_rank_max = CHAN_RANK_MAX_ON_SPR,
> + .dimm_idx_max = DIMM_IDX_MAX_ON_SPR,
> + .min_peci_revision = 0x40,
> + .read_thresholds = &read_thresholds_spr,
> +};
> +
> static const struct auxiliary_device_id peci_dimmtemp_ids[] = {
> {
> .name = "peci_cpu.dimmtemp.hsx",
> @@ -601,6 +619,10 @@ static const struct auxiliary_device_id peci_dimmtemp_ids[] = {
> .name = "peci_cpu.dimmtemp.icxd",
> .driver_data = (kernel_ulong_t)&dimm_icxd,
> },
> + {
> + .name = "peci_cpu.dimmtemp.spr",
> + .driver_data = (kernel_ulong_t)&dimm_spr,
> + },
> { }
> };
> MODULE_DEVICE_TABLE(auxiliary, peci_dimmtemp_ids);
> --
> 2.41.0
>