Re: [PATCH net-next v3 2/3] net: stmmac: Integrate dwxgmac4 into stmmac hwif handling

[Serge Semin]

On Thu, Aug 01, 2024 at 08:18:21PM -0700, jitendra.vegiraju@xxxxxxxxxxxx wrote:
> From: Jitendra Vegiraju <jitendra.vegiraju@xxxxxxxxxxxx>
> 
> Integrate dwxgmac4 support into stmmac hardware interface handling.
> A dwxgmac4 is an xgmac device and hence it inherits properties from
> existing stmmac_hw table entry.
> The quirks handling facility is used to update dma_ops field to
> point to dwxgmac400_dma_ops when the user version field matches.
> 
> Signed-off-by: Jitendra Vegiraju <jitendra.vegiraju@xxxxxxxxxxxx>
> ---
>  drivers/net/ethernet/stmicro/stmmac/common.h |  4 +++
>  drivers/net/ethernet/stmicro/stmmac/hwif.c   | 26 +++++++++++++++++++-
>  drivers/net/ethernet/stmicro/stmmac/hwif.h   |  1 +
>  3 files changed, 30 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
> index cd36ff4da68c..9bf278e11704 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/common.h
> +++ b/drivers/net/ethernet/stmicro/stmmac/common.h
> @@ -37,11 +37,15 @@
>  #define DWXGMAC_CORE_2_10	0x21
>  #define DWXGMAC_CORE_2_20	0x22
>  #define DWXLGMAC_CORE_2_00	0x20

> +#define DWXGMAC_CORE_4_00	0x40

DW25GMAC_CORE_4_00?

>  
>  /* Device ID */
>  #define DWXGMAC_ID		0x76

What is the device ID in your case? Does it match to DWXGMAC_ID?

>  #define DWXLGMAC_ID		0x27
>  
> +/* User Version */
> +#define DWXGMAC_USER_VER_X22	0x22
> +
>  #define STMMAC_CHAN0	0	/* Always supported and default for all chips */
>  
>  /* TX and RX Descriptor Length, these need to be power of two.
> diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.c b/drivers/net/ethernet/stmicro/stmmac/hwif.c
> index 29367105df54..713cb5aa2c3e 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/hwif.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/hwif.c
> @@ -36,6 +36,18 @@ static u32 stmmac_get_dev_id(struct stmmac_priv *priv, u32 id_reg)
>  	return (reg & GENMASK(15, 8)) >> 8;
>  }
>  

> +static u32 stmmac_get_user_version(struct stmmac_priv *priv, u32 id_reg)
> +{
> +	u32 reg = readl(priv->ioaddr + id_reg);
> +
> +	if (!reg) {
> +		dev_info(priv->device, "User Version not available\n");
> +		return 0x0;
> +	}
> +
> +	return (reg & GENMASK(23, 16)) >> 16;
> +}
> +

The User Version is purely a vendor-specific stuff defined on the
IP-core synthesis stage. Moreover I don't see you'll need it anyway.

>  static void stmmac_dwmac_mode_quirk(struct stmmac_priv *priv)
>  {
>  	struct mac_device_info *mac = priv->hw;
> @@ -82,6 +94,18 @@ static int stmmac_dwmac4_quirks(struct stmmac_priv *priv)
>  	return 0;
>  }
>  

> +static int stmmac_dwxgmac_quirks(struct stmmac_priv *priv)
> +{
> +	struct mac_device_info *mac = priv->hw;
> +	u32 user_ver;
> +
> +	user_ver = stmmac_get_user_version(priv, GMAC4_VERSION);
> +	if (priv->synopsys_id == DWXGMAC_CORE_4_00 &&
> +	    user_ver == DWXGMAC_USER_VER_X22)
> +		mac->dma = &dwxgmac400_dma_ops;
> +	return 0;
> +}
> +
>  static int stmmac_dwxlgmac_quirks(struct stmmac_priv *priv)
>  {
>  	priv->hw->xlgmac = true;
> @@ -256,7 +280,7 @@ static const struct stmmac_hwif_entry {
>  		.mmc = &dwxgmac_mmc_ops,
>  		.est = &dwmac510_est_ops,
>  		.setup = dwxgmac2_setup,
> -		.quirks = NULL,
> +		.quirks = stmmac_dwxgmac_quirks,

Why? You can just introduce a new stmmac_hw[] entry with the DW
25GMAC-specific stmmac_dma_ops instance specified.

-Serge(y)

>  	}, {
>  		.gmac = false,
>  		.gmac4 = false,
> diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h
> index e53c32362774..6213c496385c 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/hwif.h
> +++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h
> @@ -683,6 +683,7 @@ extern const struct stmmac_desc_ops dwxgmac210_desc_ops;
>  extern const struct stmmac_mmc_ops dwmac_mmc_ops;
>  extern const struct stmmac_mmc_ops dwxgmac_mmc_ops;
>  extern const struct stmmac_est_ops dwmac510_est_ops;
> +extern const struct stmmac_dma_ops dwxgmac400_dma_ops;
>  
>  #define GMAC_VERSION		0x00000020	/* GMAC CORE Version */
>  #define GMAC4_VERSION		0x00000110	/* GMAC4+ CORE Version */
> -- 
> 2.34.1
> 
>