Re: [PATCH 10/15] ice: add basic handler for devlink .info_get

[Jakub Kicinski <kuba@kernel.org>]

On Thu, 30 Jan 2020 14:59:05 -0800, Jacob Keller wrote:
> The devlink .info_get callback allows the driver to report detailed
> version information. The following devlink versions are reported with
> this initial implementation:
> 
>  "driver.version" -> device driver version, to match ethtool -i version
>  "fw" -> firmware version as reported by ethtool -i firmware-version
>  "fw.mgmt" -> The version of the firmware that controls PHY, link, etc
>  "fw.api" -> API version of interface exposed over the AdminQ
>  "fw.build" -> Unique build identifier for the management firmware
>  "nvm.version" -> Version of the NVM parameters section
>  "nvm.oem" -> OEM-specific version information
>  "nvm.eetrack" -> Unique identifier for the combined NVM image

These all need documentation.

> With this, devlink can now report at least the same information as
> reported by the older ethtool interface. Each section of the
> "firmware-version" is also reported independently so that it is easier
> to understand the meaning.
> 
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> ---
>  drivers/net/ethernet/intel/ice/ice_devlink.c | 103 +++++++++++++++++++
>  1 file changed, 103 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_devlink.c b/drivers/net/ethernet/intel/ice/ice_devlink.c
> index 0b0f936122de..493c2c2986f2 100644
> --- a/drivers/net/ethernet/intel/ice/ice_devlink.c
> +++ b/drivers/net/ethernet/intel/ice/ice_devlink.c
> @@ -2,9 +2,112 @@
>  /* Copyright (c) 2019, Intel Corporation. */
>  
>  #include "ice.h"
> +#include "ice_lib.h"
>  #include "ice_devlink.h"
>  
> +/**
> + * ice_devlink_info_get - .info_get devlink handler
> + * @devlink: devlink instance structure
> + * @req: the devlink info request
> + * @extack: extended netdev ack structure
> + *
> + * Callback for the devlink .info_get operation. Reports information about the
> + * device.
> + *
> + * @returns zero on success or an error code on failure.
> + */
> +static int ice_devlink_info_get(struct devlink *devlink,
> +				struct devlink_info_req *req,
> +				struct netlink_ext_ack *extack)
> +{
> +	u8 oem_ver, oem_patch, nvm_ver_hi, nvm_ver_lo;
> +	struct ice_pf *pf = devlink_priv(devlink);
> +	struct ice_hw *hw = &pf->hw;
> +	u16 oem_build;
> +	char buf[32]; /* TODO: size this properly */
> +	int err;
> +
> +	ice_get_nvm_version(hw, &oem_ver, &oem_build, &oem_patch, &nvm_ver_hi,
> +			    &nvm_ver_lo);
> +
> +	err = devlink_info_driver_name_put(req, KBUILD_MODNAME);
> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set driver name");
> +		return err;
> +	}
> +
> +	/* driver.version */
> +	err = devlink_info_version_fixed_put(req, "driver.version",
> +					     ice_drv_ver);

Hard no. You should really try to follow the discussions on netdev.

> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set driver version");
> +		return err;
> +	}
> +
> +	/* fw (match exact output of ethtool -i firmware-version) */

That's generally a bad idea, the whole point of info was that people
were stuffing multiple things into ethtool -i fw. Is this only one item
referring to one single entity?

> +	err = devlink_info_version_running_put(req,
> +					       DEVLINK_INFO_VERSION_GENERIC_FW,
> +					       ice_nvm_version_str(hw));
> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set combined fw version");
> +		return err;
> +	}
> +
> +	/* fw.mgmt (DEVLINK_INFO_VERSION_GENERIC_FW_MGMT) */
> +	snprintf(buf, sizeof(buf), "%u.%u.%u", hw->fw_maj_ver, hw->fw_min_ver,
> +		 hw->fw_patch);
> +	err = devlink_info_version_running_put(req, "fw.mgmt", buf);

why not use the define?

> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set fw version data");
> +		return err;
> +	}
> +
> +	/* fw.api */
> +	snprintf(buf, sizeof(buf), "%u.%u", hw->api_maj_ver,
> +		 hw->api_min_ver);
> +	err = devlink_info_version_running_put(req, "fw.api", buf);

Is this the API version of the management FW? I'd go for "fw.mgmt.api".
Datapath, RoCE and other bits may have APIs which evolve independently
for complex chips.

> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set fw API data");
> +		return err;
> +	}
> +
> +	/* fw.build */
> +	snprintf(buf, sizeof(buf), "%08x", hw->fw_build);
> +	err = devlink_info_version_running_put(req, "fw.build", buf);

Huh? Why is this not part of the version?

Maybe you want to use fw.bundle? Naming is hard, at Netronome added
that as a unique identifier for the FW in its entirety / the entire
build as it is passed from Eng to QA and released externally.

> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set fw build data");
> +		return err;
> +	}
> +
> +	/* nvm.version */
> +	snprintf(buf, sizeof(buf), "%x.%02x", nvm_ver_hi, nvm_ver_lo);
> +	err = devlink_info_version_running_put(req, "nvm.version", buf);

Please us the psid 

> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set NVM version data");
> +		return err;
> +	}
> +
> +	/* nvm.oem */
> +	snprintf(buf, sizeof(buf), "%u.%u.%u", oem_ver, oem_build, oem_patch);
> +	err = devlink_info_version_running_put(req, "nvm.oem", buf);

This looks like free form catch all. Let's not.

> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set oem version data");
> +		return err;
> +	}
> +
> +	/* nvm.eetrack */
> +	snprintf(buf, sizeof(buf), "0x%0X", hw->nvm.eetrack);

Mm. maybe this is bundle? Or psid. Hm. Please explain what this is and
what it's supposed to be used for. I should probably add more docs to
the existing items :S

> +	err = devlink_info_version_running_put(req, "nvm.eetrack", buf);
> +	if (err) {
> +		NL_SET_ERR_MSG_MOD(extack, "Unable to set NVM eetrack data");
> +		return err;
> +	}
> +
> +	return 0;
> +}
> +
>  const struct devlink_ops ice_devlink_ops = {
> +	.info_get = ice_devlink_info_get,
>  };
>  
>  /**