On Thu, Jan 19, 2023 at 11:45 PM Marek Vasut <ma...@denx.de> wrote:
>
> The driver currently only waits for DMA_MODE SWR bit to clear itself.
> This is insufficient e.g. on i.MX8M Plus, where the MAC must be reset
> before IOMUX GPR[1] content is latched into the MAC and used. Without
> the proper reset, the i.MX8M Plus MAC variant does not take the value
> in IOMUX GPR[1] into account, which makes it impossible e.g. to switch
> interface mode from RGMII to any other.
>
> Since proper reset is desired in general to put the block into defined
> state, always assert the DMA_MODE SWR bit before waiting for the bit
> to clear itself.
>
> Signed-off-by: Marek Vasut <ma...@denx.de>
> ---
> Cc: "Ariel D'Alessandro" <ariel.dalessan...@collabora.com>
> Cc: "NXP i.MX U-Boot Team" <uboot-...@nxp.com>
> Cc: Andrey Zhizhikin <andrey.zhizhi...@leica-geosystems.com>
> Cc: Fabio Estevam <feste...@gmail.com>
> Cc: Joe Hershberger <joe.hershber...@ni.com>
> Cc: Lukasz Majewski <lu...@denx.de>
> Cc: Marcel Ziswiler <marcel.ziswi...@toradex.com>
> Cc: Marek Vasut <ma...@denx.de>
> Cc: Michael Trimarchi <mich...@amarulasolutions.com>
> Cc: Peng Fan <peng....@nxp.com>
> Cc: Ramon Fried <rfried....@gmail.com>
> Cc: Sean Anderson <sean...@gmail.com>
> Cc: Stefano Babic <sba...@denx.de>
> Cc: Tim Harvey <thar...@gateworks.com>
> Cc: Tommaso Merciai <tommaso.merc...@amarulasolutions.com>
> Cc: u-boot@lists.denx.de
> ---
> drivers/net/dwc_eth_qos.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/net/dwc_eth_qos.c b/drivers/net/dwc_eth_qos.c
> index cd2def4ba21..d488bd0c288 100644
> --- a/drivers/net/dwc_eth_qos.c
> +++ b/drivers/net/dwc_eth_qos.c
> @@ -761,6 +761,12 @@ static int eqos_start(struct udevice *dev)
>
> eqos->reg_access_ok = true;
>
> + /*
> + * Assert the SWR first, the actually reset the MAC and to latch in
> + * e.g. i.MX8M Plus GPR[1] content, which selects interface mode.
> + */
> + setbits_le32(&eqos->dma_regs->mode, EQOS_DMA_MODE_SWR);
> +
> ret = wait_for_bit_le32(&eqos->dma_regs->mode,
> EQOS_DMA_MODE_SWR, false,
> eqos->config->swr_wait, false);
> --
> 2.39.0
>
Reviewed-by: Ramon Fried <rfried....@gmail.com>
