[PATCH 07/14] net: dwc_eth_qos: Allow platform to override tx/rx_fifo_sz

[Ramon Fried]

On Fri, Jan 20, 2023 at 9:18 AM Sumit Garg <sumit.garg at linaro.org> wrote:
>
> The GMAC controller on QCS404 SoC (support added by upcoming patch) fails
> to work with maximum tx/rx_fifo_sz supported by the hardware (16K). So
> allow platforms to override FIFO size using corresponding DT node
> properties.
>
> Signed-off-by: Sumit Garg <sumit.garg at linaro.org>
> ---
>  drivers/net/dwc_eth_qos.c | 19 +++++++++++++------
>  drivers/net/dwc_eth_qos.h |  1 +
>  2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/dwc_eth_qos.c b/drivers/net/dwc_eth_qos.c
> index 753a912607..65b8556be2 100644
> --- a/drivers/net/dwc_eth_qos.c
> +++ b/drivers/net/dwc_eth_qos.c
> @@ -852,12 +852,19 @@ static int eqos_start(struct udevice *dev)
>         rx_fifo_sz = (val >> EQOS_MAC_HW_FEATURE1_RXFIFOSIZE_SHIFT) &
>                 EQOS_MAC_HW_FEATURE1_RXFIFOSIZE_MASK;
>
> -       /*
> -        * r/tx_fifo_sz is encoded as log2(n / 128). Undo that by shifting.
> -        * r/tqs is encoded as (n / 256) - 1.
> -        */
> -       tqs = (128 << tx_fifo_sz) / 256 - 1;
> -       rqs = (128 << rx_fifo_sz) / 256 - 1;
> +       /* r/tx_fifo_sz is encoded as log2(n / 128). Undo that by shifting */
> +       tx_fifo_sz = 128 << tx_fifo_sz;
> +       rx_fifo_sz = 128 << rx_fifo_sz;
> +
> +       /* Allow platform to override TX/RX fifo size */
> +       if (eqos->tx_fifo_sz)
> +               tx_fifo_sz = eqos->tx_fifo_sz;
> +       if (eqos->rx_fifo_sz)
> +               rx_fifo_sz = eqos->rx_fifo_sz;
> +
> +       /* r/tqs is encoded as (n / 256) - 1 */
> +       tqs = tx_fifo_sz / 256 - 1;
> +       rqs = rx_fifo_sz / 256 - 1;
>
>         clrsetbits_le32(&eqos->mtl_regs->txq0_operation_mode,
>                         EQOS_MTL_TXQ0_OPERATION_MODE_TQS_MASK <<
> diff --git a/drivers/net/dwc_eth_qos.h b/drivers/net/dwc_eth_qos.h
> index 8fccd6f057..466a792de7 100644
> --- a/drivers/net/dwc_eth_qos.h
> +++ b/drivers/net/dwc_eth_qos.h
> @@ -276,6 +276,7 @@ struct eqos_priv {
>         bool started;
>         bool reg_access_ok;
>         bool clk_ck_enabled;
> +       unsigned int tx_fifo_sz, rx_fifo_sz;
>  };
>
>  void eqos_inval_desc_generic(void *desc);
> --
> 2.34.1
>
Reviewed-by: Ramon Fried <rfried.dev at gmail.com>