Re: [PATCH 2/2] net: macb: Update tsu clk usage in runtime suspend/resume for Versal

[Claudiu.Beznea]

On 20.07.2022 14:29, Harini Katakam wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On Versal TSU clock cannot be disabled irrespective of whether PTP is
> used. Hence introduce a new Versal config structure with a "need tsu"
> caps flag and check the same in runtime_suspend/resume before cutting
> off clocks.
> 
> More information on this for future reference:
> This is an IP limitation on versions 1p11 and 1p12 when Qbv is enabled
> (See designcfg1, bit 3). However it is better to rely on an SoC specific
> check rather than the IP version because tsu clk property itself may not
> represent actual HW tsu clock on some chip designs.
> 
> Signed-off-by: Harini Katakam <harini.katakam@xxxxxxxxxx>
> Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
> ---
>  drivers/net/ethernet/cadence/macb.h      |  1 +
>  drivers/net/ethernet/cadence/macb_main.c | 17 +++++++++++++++--
>  2 files changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
> index 7ca077b65eaa..8bf67b44b466 100644
> --- a/drivers/net/ethernet/cadence/macb.h
> +++ b/drivers/net/ethernet/cadence/macb.h
> @@ -725,6 +725,7 @@
>  #define MACB_CAPS_MACB_IS_GEM                  0x80000000
>  #define MACB_CAPS_PCS                          0x01000000
>  #define MACB_CAPS_HIGH_SPEED                   0x02000000
> +#define MACB_CAPS_NEED_TSUCLK                  0x00001000

Can you keep this sorted by the bit position used?

> 
>  /* LSO settings */
>  #define MACB_LSO_UFO_ENABLE                    0x01
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index 7eb7822cd184..8bbc46e8a9eb 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -4735,6 +4735,16 @@ static const struct macb_config zynqmp_config = {
>         .usrio = &macb_default_usrio,
>  };
> 
> +static const struct macb_config versal_config = {
> +       .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
> +               MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH | MACB_CAPS_NEED_TSUCLK,
> +       .dma_burst_length = 16,
> +       .clk_init = macb_clk_init,
> +       .init = init_reset_optional,
> +       .jumbo_max_len = 10240,
> +       .usrio = &macb_default_usrio,
> +};
> +

Also, could you keep this not b/w zynq configs to have a bit of sort of these?

Other than this:

Reviewed-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>


>  static const struct macb_config zynq_config = {
>         .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_NO_GIGABIT_HALF |
>                 MACB_CAPS_NEEDS_RSTONUBR,
> @@ -4794,6 +4804,7 @@ static const struct of_device_id macb_dt_ids[] = {
>         { .compatible = "microchip,mpfs-macb", .data = &mpfs_config },
>         { .compatible = "microchip,sama7g5-gem", .data = &sama7g5_gem_config },
>         { .compatible = "microchip,sama7g5-emac", .data = &sama7g5_emac_config },
> +       { .compatible = "cdns,versal-gem", .data = &versal_config},
>         { /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, macb_dt_ids);
> @@ -5203,7 +5214,7 @@ static int __maybe_unused macb_runtime_suspend(struct device *dev)
> 
>         if (!(device_may_wakeup(dev)))
>                 macb_clks_disable(bp->pclk, bp->hclk, bp->tx_clk, bp->rx_clk, bp->tsu_clk);
> -       else
> +       else if (!(bp->caps & MACB_CAPS_NEED_TSUCLK))
>                 macb_clks_disable(NULL, NULL, NULL, NULL, bp->tsu_clk);
> 
>         return 0;
> @@ -5219,8 +5230,10 @@ static int __maybe_unused macb_runtime_resume(struct device *dev)
>                 clk_prepare_enable(bp->hclk);
>                 clk_prepare_enable(bp->tx_clk);
>                 clk_prepare_enable(bp->rx_clk);
> +               clk_prepare_enable(bp->tsu_clk);
> +       } else if (!(bp->caps & MACB_CAPS_NEED_TSUCLK)) {
> +               clk_prepare_enable(bp->tsu_clk);
>         }
> -       clk_prepare_enable(bp->tsu_clk);
> 
>         return 0;
>  }
> --
> 2.17.1
>