[RFC,v6,0/2] Introduce ICSSG based ethernet Driver

The Programmable Real-time Unit and Industrial Communication Subsystem
Gigabit (PRU_ICSSG) is a low-latency microcontroller subsystem in the TI
SoCs. This subsystem is provided for the use cases like the implementation
of custom peripheral interfaces, offloading of tasks from the other
processor cores of the SoC, etc.

The subsystem includes many accelerators for data processing like
multiplier and multiplier-accumulator. It also has peripherals like
UART, MII/RGMII, MDIO, etc. Every ICSSG core includes two 32-bit
load/store RISC CPU cores called PRUs.

The above features allow it to be used for implementing custom firmware
based peripherals like ethernet.

This series adds the YAML documentation and the driver with basic EMAC
support for TI AM654 Silicon Rev 2 SoC with the PRU_ICSSG Sub-system.
running dual-EMAC firmware.
This currently supports basic EMAC with 1Gbps and 100Mbps link. 10M and
half-duplex modes are not yet supported because they require the support
of an IEP, which will be added later.
Advanced features like switch-dev and timestamping will be added later.

This series depends on a patch series [1] which is yet to be merged. The seires
[1] is posted to SoC tree, has already been reviewed and is ready to be merged.
Currently I am posting this series as RFC to get it reviewed. Once [1] is
merged, this series can also be merged. 

This is the v6 of the patch series [v1]. This version of the patchset 
addresses the comments made on [v5] of the series. 

Changes from v5 to v6 :
*) Added RB tag of Andrew Lunn in patch 2 of this series.
*) Addressed Rob's comment on patch 1 of the series.
*) Rebased patchset on next-20230421 linux-next.

Changes from v4 to v5 :
*) Re-arranged properties section in ti,icssg-prueth.yaml file.
*) Added requirement for minimum one ethernet port.
*) Fixed some minor formatting errors as asked by Krzysztof.
*) Dropped SGMII mode from enum mii_mode as SGMII mode is not currently
   supported by the driver.
*) Added switch-case block to handle different phy modes by ICSSG driver.

Changes from v3 to v4 :
*) Addressed Krzysztof's comments and fixed dt_binding_check errors in 
   patch 1/2.
*) Added interrupt-extended property in ethernet-ports properties section.
*) Fixed comments in file icssg_switch_map.h according to the Linux coding
   style in patch 2/2. Added Documentation of structures in patch 2/2.

Changes from v2 to v3 :
*) Addressed Rob and Krzysztof's comments on patch 1 of this series.
   Fixed indentation. Removed description and pinctrl section from 
   ti,icssg-prueth.yaml file.
*) Addressed Krzysztof, Paolo, Randy, Andrew and Christophe's comments on 
   patch 2 of this seires.
*) Fixed blanklines in Kconfig and Makefile. Changed structures to const 
   as suggested by Krzysztof.
*) Fixed while loop logic in emac_tx_complete_packets() API as suggested 
   by Paolo. Previously in the loop's last iteration 'budget' was 0 and 
   napi_consume_skb would wrongly assume the caller is not in NAPI context
   Now, budget won't be zero in last iteration of loop. 
*) Removed inline functions addr_to_da1() and addr_to_da0() as asked by 
   Andrew.
*) Added dev_err_probe() instead of dev_err() as suggested by Christophe.
*) In ti,icssg-prueth.yaml file, in the patternProperties section of 
   ethernet-ports, kept the port name as "port" instead of "ethernet-port" 
   as all other drivers were using "port". Will change it if is compulsory 
   to use "ethernet-port".

[1] https://lore.kernel.org/all/20230414045542.3249939-1-danishanwar@ti.com/

[v1] https://lore.kernel.org/all/20220506052433.28087-1-p-mohan@ti.com/
[v2] https://lore.kernel.org/all/20220531095108.21757-1-p-mohan@ti.com/
[v3] https://lore.kernel.org/all/20221223110930.1337536-1-danishanwar@ti.com/
[v4] https://lore.kernel.org/all/20230206060708.3574472-1-danishanwar@ti.com/
[v5] https://lore.kernel.org/all/20230210114957.2667963-1-danishanwar@ti.com/

Thanks and Regards,
Md Danish Anwar

MD Danish Anwar (1):
  dt-bindings: net: Add ICSSG Ethernet

Roger Quadros (1):
  net: ti: icssg-prueth: Add ICSSG ethernet driver

 .../bindings/net/ti,icssg-prueth.yaml         |  184 ++
 drivers/net/ethernet/ti/Kconfig               |   13 +
 drivers/net/ethernet/ti/Makefile              |    2 +
 drivers/net/ethernet/ti/icssg_classifier.c    |  369 ++++
 drivers/net/ethernet/ti/icssg_config.c        |  448 ++++
 drivers/net/ethernet/ti/icssg_config.h        |  200 ++
 drivers/net/ethernet/ti/icssg_ethtool.c       |  326 +++
 drivers/net/ethernet/ti/icssg_mii_cfg.c       |  104 +
 drivers/net/ethernet/ti/icssg_mii_rt.h        |  150 ++
 drivers/net/ethernet/ti/icssg_prueth.c        | 1863 +++++++++++++++++
 drivers/net/ethernet/ti/icssg_prueth.h        |  247 +++
 drivers/net/ethernet/ti/icssg_switch_map.h    |  234 +++
 12 files changed, 4140 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml
 create mode 100644 drivers/net/ethernet/ti/icssg_classifier.c
 create mode 100644 drivers/net/ethernet/ti/icssg_config.c
 create mode 100644 drivers/net/ethernet/ti/icssg_config.h
 create mode 100644 drivers/net/ethernet/ti/icssg_ethtool.c
 create mode 100644 drivers/net/ethernet/ti/icssg_mii_cfg.c
 create mode 100644 drivers/net/ethernet/ti/icssg_mii_rt.h
 create mode 100644 drivers/net/ethernet/ti/icssg_prueth.c
 create mode 100644 drivers/net/ethernet/ti/icssg_prueth.h
 create mode 100644 drivers/net/ethernet/ti/icssg_switch_map.h

On Mon, 24 Apr 2023 11:02:32 +0530, MD Danish Anwar wrote:
> Add a YAML binding document for the ICSSG Programmable real time unit
> based Ethernet hardware. The ICSSG driver uses the PRU and PRUSS consumer
> APIs to interface the PRUs and load/run the firmware for supporting
> ethernet functionality.
> 
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> ---
>  .../bindings/net/ti,icssg-prueth.yaml         | 184 ++++++++++++++++++
>  1 file changed, 184 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml
> 

Reviewed-by: Rob Herring <robh@kernel.org>