[PATCH v2] net: zynq: Add support for GEM reset

[Ramon Fried]

On Mon, Dec 6, 2021 at 5:25 PM Michal Simek <michal.simek at xilinx.com> wrote:
>
> Perform reset before core initialization.
> Standard flow which close to 99% users are using getting all IPs out of
> reset that there is no need to reset IP again. This is because of all low
> level initialization is done in previous bootloader stage.
> In SOM case these IPs are not touched by previous bootloader stage that's
> why reset needs to be called before IP is accessed to make sure that it is
> in correct state.
>
> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
> ---
>
> Changes in v2:
> - Update commit message
>
>  drivers/net/zynq_gem.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
>
> diff --git a/drivers/net/zynq_gem.c b/drivers/net/zynq_gem.c
> index 91957757727d..5cbe8d28304b 100644
> --- a/drivers/net/zynq_gem.c
> +++ b/drivers/net/zynq_gem.c
> @@ -21,6 +21,7 @@
>  #include <asm/cache.h>
>  #include <asm/io.h>
>  #include <phy.h>
> +#include <reset.h>
>  #include <miiphy.h>
>  #include <wait_bit.h>
>  #include <watchdog.h>
> @@ -217,6 +218,7 @@ struct zynq_gem_priv {
>         bool int_pcs;
>         bool dma_64bit;
>         u32 clk_en_info;
> +       struct reset_ctl_bulk resets;
>  };
>
>  static int phy_setup_op(struct zynq_gem_priv *priv, u32 phy_addr, u32 regnum,
> @@ -688,12 +690,36 @@ static int zynq_gem_miiphy_write(struct mii_dev *bus, int addr, int devad,
>         return phywrite(priv, addr, reg, value);
>  }
>
> +static int zynq_gem_reset_init(struct udevice *dev)
> +{
> +       struct zynq_gem_priv *priv = dev_get_priv(dev);
> +       int ret;
> +
> +       ret = reset_get_bulk(dev, &priv->resets);
> +       if (ret == -ENOTSUPP || ret == -ENOENT)
> +               return 0;
> +       else if (ret)
> +               return ret;
> +
> +       ret = reset_deassert_bulk(&priv->resets);
> +       if (ret) {
> +               reset_release_bulk(&priv->resets);
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
>  static int zynq_gem_probe(struct udevice *dev)
>  {
>         void *bd_space;
>         struct zynq_gem_priv *priv = dev_get_priv(dev);
>         int ret;
>
> +       ret = zynq_gem_reset_init(dev);
> +       if (ret)
> +               return ret;
> +
>         /* Align rxbuffers to ARCH_DMA_MINALIGN */
>         priv->rxbuffers = memalign(ARCH_DMA_MINALIGN, RX_BUF * PKTSIZE_ALIGN);
>         if (!priv->rxbuffers)
> --
> 2.33.1
>
Reviewed-by: Ramon Fried <rfried.dev at gmail.com>