| Message ID | 20200921175442.16789-1-skardach@marvell.com |
|---|---|
| Headers | show |
| Series | octeontx2-af: add support for KPU profile customization | expand |
Please create a proper abstraction for uploading configuration information from a file into a device. Otherwise every driver will have their own custom weird stuff, unique module parameter names (module parameters are absolutely rejected for networking drivers for this reason), etc. Therefore the user experience will be awful. This is non-negotiable. We are long overdue for such a facility, and if I were to allow a workaround like this for you, I have to allow it for everyone else too. Thank you.
Marvell octeontx2 NPC device contains a configurable Kanguroo Parser Unit (KPU) and CAM match key data extraction (MKEX). The octeontx2-af driver configures them both to parse a list of standard protocol headers which are used by netdev driver and other potential applications (i.e. userspace through VFIO). The problem arises when users have some custom protocol headers which they'd like to use in CAM flow matching. If such protocols are publicly known, they can be added to the built-in KPU configuration (called "profile" - in npc_profile.h). If not, then there's more benefit in keeping such changes local to the user. For that case a mechanism which would allow users to produce a KPU profile and load it along with octeontx2-af driver is needed. At the same time such customization has to take care not to break the netdev driver operation or other applications (that is be discoverable). Therefore introduce a mechanism for a limited customization of the built-in KPU profile via a firmware file (layout and contents described by struct npc_kpu_profile_fwdata). It allows user modification of only a limited number of top priority KPU entries, while others are configured from the built-in KPU profile. Additionally by convention users should only use NPC_LT_Lx_CUSTOMx LTYPE entries in their profiles to change the meaning of built-in LTYPEs. This way the baseline protocol support is always available and the impact of potential user errors is minimized. As MKEX also needs to be modified to take into account any user protocols, the KPU profile firmware binary contains also that. Netdev driver and applications have a way to discover applied MKEX settings by querying RVU AF device via NPC_GET_KEX_CFG MBOX message. Finally some users might need to modify hardware packet data alignment behavior and profile contains settings for that too. First patch ensures that CUSTOMx LTYPEs are not aliased with meaningful LTYPEs where possible. Second patch gathers all KPU profile related data into a single struct and creates an adapter structure which provides an interface to the KPU profile for the octeontx2-af driver. Third patch adds logic for loading the KPU profile through kernel firmware APIs, filling in the customizable entries in the adapter structure and programming the MKEX from KPU profile. Changes from v1: * Remove unnecessary __packed attributes. All structures in profile are naturally aligned and only struct npc_kpu_profile_fwdata is padded 1B at the end, which is expected. * Make npc_lt_defaults and npc_mkex_default const as they are read-only. * Save custom KPU entries in separate struct npc_kpu_profile so that the default profile can remain read-only and there's no need to allocate and memcpy 25kB of default profile when customizations are present. The drawbacks are weaker profile abstraction and slightly more complicated programming steps. This is a result of: 4a681bf3456f octeontx2-af: Constify npc_kpu_profile_{action,cam} * Describe in last commit the reason for using a module parameter instead of an arbitrary firmware name. Stanislaw Kardach (3): octeontx2-af: fix LD CUSTOM LTYPE aliasing octeontx2-af: prepare for custom KPU profiles octeontx2-af: add support for custom KPU entries .../net/ethernet/marvell/octeontx2/af/npc.h | 76 +++- .../marvell/octeontx2/af/npc_profile.h | 244 +++++++++++- .../net/ethernet/marvell/octeontx2/af/rvu.c | 6 + .../net/ethernet/marvell/octeontx2/af/rvu.h | 22 ++ .../ethernet/marvell/octeontx2/af/rvu_nix.c | 36 +- .../ethernet/marvell/octeontx2/af/rvu_npc.c | 368 +++++++++++------- 6 files changed, 587 insertions(+), 165 deletions(-)