Re: [PATCH net-next v5 3/9] net: stmmac: enlarge max rx/tx queues and channels to 16

[Serge Semin]

On Fri, Aug 18, 2023 at 12:57:43AM +0800, Jisheng Zhang wrote:
> xgmac supports up to 16 rx/tx queues and up to 16 channels.
> 
> Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
> Acked-by: Alexandre TORGUE <alexandre.torgue@xxxxxxxxxxx>
> ---
>  drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c | 5 ++---
>  include/linux/stmmac.h                              | 6 +++---
>  2 files changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
> index 38782662ff98..8ac994553bc1 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
> @@ -232,9 +232,8 @@ static void dwxgmac2_map_mtl_to_dma(struct mac_device_info *hw, u32 queue,
>  	void __iomem *ioaddr = hw->pcsr;
>  	u32 value, reg;
>  
> -	reg = (queue < 4) ? XGMAC_MTL_RXQ_DMA_MAP0 : XGMAC_MTL_RXQ_DMA_MAP1;
> -	if (queue >= 4)
> -		queue -= 4;
> +	reg = XGMAC_MTL_RXQ_DMA_MAP0 + (queue & ~0x3);
> +	queue &= 0x3;
>  
>  	value = readl(ioaddr + reg);
>  	value &= ~XGMAC_QxMDMACH(queue);
> diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
> index 784277d666eb..9c90e2e295d4 100644
> --- a/include/linux/stmmac.h
> +++ b/include/linux/stmmac.h
> @@ -15,9 +15,9 @@
>  #include <linux/platform_device.h>
>  #include <linux/phy.h>
>  
> -#define MTL_MAX_RX_QUEUES	8
> -#define MTL_MAX_TX_QUEUES	8
> -#define STMMAC_CH_MAX		8

> +#define MTL_MAX_RX_QUEUES	16

In DW XGMAC 2.11a (Databook from 9.2015) number of MTL Rx queues is
limited with 12:
Number of Receive Queues	Description: Specifies the number of receive queues.
				Value Range: 1–12
				Default Value: 1
				Dependencies: This option is not available in XGMAC-CORE configurations.
				HDL Parameter Name: DWCXG_NUM_RXQ

Are you sure it's different in your case? Do you have a Synopsys HW
manual with the DWCXG_NUM_RXQ parameter range limited to 16? What
IP-core version is it about?

-Serge(y)

> +#define MTL_MAX_TX_QUEUES	16
> +#define STMMAC_CH_MAX		16
>  
>  #define STMMAC_RX_COE_NONE	0
>  #define STMMAC_RX_COE_TYPE1	1
> -- 
> 2.40.1
> 
>