Help¶

Number of network buffers that will be permanently allocated by the Ethernet driver. These buffers are used in receive path. They are preallocated by the driver and made available to the GMAC module to be filled in with incoming data. Their number has to be large enough to fit at least one complete Ethernet frame. SAM ETH driver will always allocate that amount of buffers for itself thus reducing the NET_BUF_RX_COUNT which is a total amount of RX data buffers used by the whole networking stack. One has to ensure that NET_PKT_RX_COUNT is large enough to fit at least two Ethernet frames: one being received by the GMAC module and the other being processed by the higher layer networking stack.

Direct dependencies¶

ETH_SAM_GMAC && NET_L2_ETHERNET

(Includes any dependencies from ifs and menus.)

Default¶

12

Kconfig definition¶

At <Zephyr>/drivers/ethernet/Kconfig.sam_gmac:56

Included via <Zephyr>/Kconfig:8 → <Zephyr>/Kconfig.zephyr:32 → <Zephyr>/drivers/Kconfig:20 → <Zephyr>/drivers/ethernet/Kconfig:51

Menu path: (Top) → Device Drivers → Ethernet Drivers → Atmel SAM Ethernet driver

config ETH_SAM_GMAC_BUF_RX_COUNT
    int "Network RX buffers preallocated by the SAM ETH driver"
    default 12
    depends on ETH_SAM_GMAC && NET_L2_ETHERNET
    help
      Number of network buffers that will be permanently allocated by the
      Ethernet driver. These buffers are used in receive path. They are
      preallocated by the driver and made available to the GMAC module to be
      filled in with incoming data. Their number has to be large enough to fit
      at least one complete Ethernet frame. SAM ETH driver will always allocate
      that amount of buffers for itself thus reducing the NET_BUF_RX_COUNT
      which is a total amount of RX data buffers used by the whole networking
      stack. One has to ensure that NET_PKT_RX_COUNT is large enough to
      fit at least two Ethernet frames: one being received by the GMAC module
      and the other being processed by the higher layer networking stack.

(The ‘depends on’ condition includes propagated dependencies from ifs and menus.)