Re: [PATCH net-next v2 04/14] sfc: evaluate vdpa support based on FW capability CLIENT_CMD_VF_PROXY

[Gautam Dawar <gdawar@amd.com>]

On 3/14/23 14:08, Martin Habets wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
>
>
> On Mon, Mar 13, 2023 at 06:09:19PM +0530, Gautam Dawar wrote:
>> On 3/10/23 10:34, Jason Wang wrote:
>>> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
>>>
>>>
>>> On Tue, Mar 7, 2023 at 7:37 PM Gautam Dawar <gautam.dawar@amd.com> wrote:
>>>> Add and update vdpa_supported field to struct efx_nic to true if
>>>> running Firmware supports CLIENT_CMD_VF_PROXY capability. This is
>>>> required to ensure DMA isolation between MCDI command buffer and guest
>>>> buffers.
>>>>
>>>> Signed-off-by: Gautam Dawar <gautam.dawar@amd.com>
>>>> ---
>>>>    drivers/net/ethernet/sfc/ef100_netdev.c | 26 +++++++++++++++---
>>>>    drivers/net/ethernet/sfc/ef100_nic.c    | 35 +++++++++----------------
>>>>    drivers/net/ethernet/sfc/ef100_nic.h    |  6 +++--
>>>>    drivers/net/ethernet/sfc/ef100_vdpa.h   |  5 ++--
>>>>    4 files changed, 41 insertions(+), 31 deletions(-)
>>>>
>>>> diff --git a/drivers/net/ethernet/sfc/ef100_netdev.c b/drivers/net/ethernet/sfc/ef100_netdev.c
>>>> index d916877b5a9a..5d93e870d9b7 100644
>>>> --- a/drivers/net/ethernet/sfc/ef100_netdev.c
>>>> +++ b/drivers/net/ethernet/sfc/ef100_netdev.c
>>>> @@ -355,6 +355,28 @@ void ef100_remove_netdev(struct efx_probe_data *probe_data)
>>>>           efx->state = STATE_PROBED;
>>>>    }
>>>>
>>>> +static void efx_ef100_update_tso_features(struct efx_nic *efx)
>>>> +{
>>>> +       struct ef100_nic_data *nic_data = efx->nic_data;
>>>> +       struct net_device *net_dev = efx->net_dev;
>>>> +       netdev_features_t tso;
>>>> +
>>>> +       if (!efx_ef100_has_cap(nic_data->datapath_caps2, TX_TSO_V3))
>>>> +               return;
>>>> +
>>>> +       tso = NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_GSO_PARTIAL |
>>>> +             NETIF_F_GSO_UDP_TUNNEL | NETIF_F_GSO_UDP_TUNNEL_CSUM |
>>>> +             NETIF_F_GSO_GRE | NETIF_F_GSO_GRE_CSUM;
>>>> +
>>>> +       net_dev->features |= tso;
>>>> +       net_dev->hw_features |= tso;
>>>> +       net_dev->hw_enc_features |= tso;
>>>> +       /* EF100 HW can only offload outer checksums if they are UDP,
>>>> +        * so for GRE_CSUM we have to use GSO_PARTIAL.
>>>> +        */
>>>> +       net_dev->gso_partial_features |= NETIF_F_GSO_GRE_CSUM;
>>>> +}
>>> I don't see a direct relationship between vDPA and the TSO capability.
>>> Is this an independent fix?
>> This isn't actually fixing any issue. This a minor code refactoring that
>> wraps-up updating of the TSO capabilities in a separate function for better
>> readability.
> There definity was an issue here: the vDPA code now needs access to the NIC
> capabilities. For this is should use the efx_ef100_init_datapath_caps below,
> but that was also doing this netdev specific stuff.
> The solution is to split up efx_ef100_init_datapath_caps into a generic API
> that vDPA can use, and this netdev specific API which should not be used by vDPA.
>
> Gautam, you could explain this API split in the description.

Sure, will update the commit description with this information.

Thanks

>
> Martin
>
>>>> +
>>>>    int ef100_probe_netdev(struct efx_probe_data *probe_data)
>>>>    {
>>>>           struct efx_nic *efx = &probe_data->efx;
>>>> @@ -387,9 +409,7 @@ int ef100_probe_netdev(struct efx_probe_data *probe_data)
>>>>                                  ESE_EF100_DP_GZ_TSO_MAX_HDR_NUM_SEGS_DEFAULT);
>>>>           efx->mdio.dev = net_dev;
>>>>
>>>> -       rc = efx_ef100_init_datapath_caps(efx);
>>>> -       if (rc < 0)
>>>> -               goto fail;
>>>> +       efx_ef100_update_tso_features(efx);
>>>>
>>>>           rc = ef100_phy_probe(efx);
>>>>           if (rc)
>>>> diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
>>>> index 8cbe5e0f4bdf..ef6e295efcf7 100644
>>>> --- a/drivers/net/ethernet/sfc/ef100_nic.c
>>>> +++ b/drivers/net/ethernet/sfc/ef100_nic.c
>>>> @@ -161,7 +161,7 @@ int ef100_get_mac_address(struct efx_nic *efx, u8 *mac_address,
>>>>           return 0;
>>>>    }
>>>>
>>>> -int efx_ef100_init_datapath_caps(struct efx_nic *efx)
>>>> +static int efx_ef100_init_datapath_caps(struct efx_nic *efx)
>>>>    {
>>>>           MCDI_DECLARE_BUF(outbuf, MC_CMD_GET_CAPABILITIES_V7_OUT_LEN);
>>>>           struct ef100_nic_data *nic_data = efx->nic_data;
>>>> @@ -197,25 +197,15 @@ int efx_ef100_init_datapath_caps(struct efx_nic *efx)
>>>>           if (rc)
>>>>                   return rc;
>>>>
>>>> -       if (efx_ef100_has_cap(nic_data->datapath_caps2, TX_TSO_V3)) {
>>>> -               struct net_device *net_dev = efx->net_dev;
>>>> -               netdev_features_t tso = NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_GSO_PARTIAL |
>>>> -                                       NETIF_F_GSO_UDP_TUNNEL | NETIF_F_GSO_UDP_TUNNEL_CSUM |
>>>> -                                       NETIF_F_GSO_GRE | NETIF_F_GSO_GRE_CSUM;
>>>> -
>>>> -               net_dev->features |= tso;
>>>> -               net_dev->hw_features |= tso;
>>>> -               net_dev->hw_enc_features |= tso;
>>>> -               /* EF100 HW can only offload outer checksums if they are UDP,
>>>> -                * so for GRE_CSUM we have to use GSO_PARTIAL.
>>>> -                */
>>>> -               net_dev->gso_partial_features |= NETIF_F_GSO_GRE_CSUM;
>>>> -       }
>>>>           efx->num_mac_stats = MCDI_WORD(outbuf,
>>>>                                          GET_CAPABILITIES_V4_OUT_MAC_STATS_NUM_STATS);
>>>>           netif_dbg(efx, probe, efx->net_dev,
>>>>                     "firmware reports num_mac_stats = %u\n",
>>>>                     efx->num_mac_stats);
>>>> +
>>>> +       nic_data->vdpa_supported = efx_ef100_has_cap(nic_data->datapath_caps3,
>>>> +                                                    CLIENT_CMD_VF_PROXY) &&
>>>> +                                  efx->type->is_vf;
>>>>           return 0;
>>>>    }
>>>>
>>>> @@ -806,13 +796,6 @@ static char *bar_config_name[] = {
>>>>           [EF100_BAR_CONFIG_VDPA] = "vDPA",
>>>>    };
>>>>
>>>> -#ifdef CONFIG_SFC_VDPA
>>>> -static bool efx_vdpa_supported(struct efx_nic *efx)
>>>> -{
>>>> -       return efx->type->is_vf;
>>>> -}
>>>> -#endif
>>>> -
>>>>    int efx_ef100_set_bar_config(struct efx_nic *efx,
>>>>                                enum ef100_bar_config new_config)
>>>>    {
>>>> @@ -828,7 +811,7 @@ int efx_ef100_set_bar_config(struct efx_nic *efx,
>>>>
>>>>    #ifdef CONFIG_SFC_VDPA
>>>>           /* Current EF100 hardware supports vDPA on VFs only */
>>>> -       if (new_config == EF100_BAR_CONFIG_VDPA && !efx_vdpa_supported(efx)) {
>>>> +       if (new_config == EF100_BAR_CONFIG_VDPA && !nic_data->vdpa_supported) {
>>>>                   pci_err(efx->pci_dev, "vdpa over PF not supported : %s",
>>>>                           efx->name);
>>>>                   return -EOPNOTSUPP;
>>>> @@ -1208,6 +1191,12 @@ static int ef100_probe_main(struct efx_nic *efx)
>>>>                   goto fail;
>>>>           }
>>>>
>>>> +       rc = efx_ef100_init_datapath_caps(efx);
>>>> +       if (rc) {
>>>> +               pci_info(efx->pci_dev, "Unable to initialize datapath caps\n");
>>>> +               goto fail;
>>>> +       }
>>>> +
>>>>           return 0;
>>>>    fail:
>>>>           return rc;
>>>> diff --git a/drivers/net/ethernet/sfc/ef100_nic.h b/drivers/net/ethernet/sfc/ef100_nic.h
>>>> index 4562982f2965..117a73d0795c 100644
>>>> --- a/drivers/net/ethernet/sfc/ef100_nic.h
>>>> +++ b/drivers/net/ethernet/sfc/ef100_nic.h
>>>> @@ -76,6 +76,9 @@ struct ef100_nic_data {
>>>>           u32 datapath_caps3;
>>>>           unsigned int pf_index;
>>>>           u16 warm_boot_count;
>>>> +#ifdef CONFIG_SFC_VDPA
>>>> +       bool vdpa_supported; /* true if vdpa is supported on this PCIe FN */
>>>> +#endif
>>>>           u8 port_id[ETH_ALEN];
>>>>           DECLARE_BITMAP(evq_phases, EFX_MAX_CHANNELS);
>>>>           enum ef100_bar_config bar_config;
>>>> @@ -95,9 +98,8 @@ struct ef100_nic_data {
>>>>    };
>>>>
>>>>    #define efx_ef100_has_cap(caps, flag) \
>>>> -       (!!((caps) & BIT_ULL(MC_CMD_GET_CAPABILITIES_V4_OUT_ ## flag ## _LBN)))
>>>> +       (!!((caps) & BIT_ULL(MC_CMD_GET_CAPABILITIES_V7_OUT_ ## flag ## _LBN)))
>>>>
>>>> -int efx_ef100_init_datapath_caps(struct efx_nic *efx);
>>>>    int ef100_phy_probe(struct efx_nic *efx);
>>>>    int ef100_filter_table_probe(struct efx_nic *efx);
>>>>
>>>> diff --git a/drivers/net/ethernet/sfc/ef100_vdpa.h b/drivers/net/ethernet/sfc/ef100_vdpa.h
>>>> index f6564448d0c7..90062fd8a25d 100644
>>>> --- a/drivers/net/ethernet/sfc/ef100_vdpa.h
>>>> +++ b/drivers/net/ethernet/sfc/ef100_vdpa.h
>>>> @@ -1,7 +1,6 @@
>>>>    /* SPDX-License-Identifier: GPL-2.0 */
>>>> -/* Driver for Xilinx network controllers and boards
>>>> - * Copyright (C) 2020-2022, Xilinx, Inc.
>>>> - * Copyright (C) 2022, Advanced Micro Devices, Inc.
>>>> +/* Driver for AMD network controllers and boards
>>>> + * Copyright (C) 2023, Advanced Micro Devices, Inc.
>>> Let's fix this in the patch that introduces this.
>> Sure, will fix.
>>
>> Thanks
>>
>>> Thanks
>>>
>>>
>>>
>>>>     *
>>>>     * This program is free software; you can redistribute it and/or modify it
>>>>     * under the terms of the GNU General Public License version 2 as published
>>>> --
>>>> 2.30.1
>>>>