Re: [PATCH 1/1] net: stmmac: dwmac4: extract MAC_HW_Feature regs MSB first

[Alexandre TORGUE]

Hi Furong

On 8/10/23 11:59, Furong Xu wrote:
> The bit extraction sequences are a little messy.
> No code changes, just reorder them.
>
> Signed-off-by: Furong Xu <0x1207@xxxxxxxxx>
> ---
>   .../net/ethernet/stmicro/stmmac/dwmac4_dma.c  | 54 +++++++++----------
>   1 file changed, 26 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
> index 84d3a8551b03..3d9e20078193 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
> @@ -379,27 +379,27 @@ static int dwmac4_get_hw_feature(void __iomem *ioaddr,
>   {
>   	u32 hw_cap = readl(ioaddr + GMAC_HW_FEATURE0);
>   
> -	/*  MAC HW feature0 */

Why to not start with the LSB ?

> -	dma_cap->mbps_10_100 = (hw_cap & GMAC_HW_FEAT_MIISEL);
> -	dma_cap->mbps_1000 = (hw_cap & GMAC_HW_FEAT_GMIISEL) >> 1;
> -	dma_cap->half_duplex = (hw_cap & GMAC_HW_FEAT_HDSEL) >> 2;
> -	dma_cap->vlhash = (hw_cap & GMAC_HW_FEAT_VLHASH) >> 4;
> +	/* MAC HW feature0 */
> +	dma_cap->vlins = (hw_cap & GMAC_HW_FEAT_SAVLANINS) >> 27;
>   	dma_cap->multi_addr = (hw_cap & GMAC_HW_FEAT_ADDMAC) >> 18;
> -	dma_cap->pcs = (hw_cap & GMAC_HW_FEAT_PCSSEL) >> 3;
> -	dma_cap->sma_mdio = (hw_cap & GMAC_HW_FEAT_SMASEL) >> 5;
> -	dma_cap->pmt_remote_wake_up = (hw_cap & GMAC_HW_FEAT_RWKSEL) >> 6;
> -	dma_cap->pmt_magic_frame = (hw_cap & GMAC_HW_FEAT_MGKSEL) >> 7;
> -	/* MMC */
> -	dma_cap->rmon = (hw_cap & GMAC_HW_FEAT_MMCSEL) >> 8;
> -	/* IEEE 1588-2008 */
> -	dma_cap->atime_stamp = (hw_cap & GMAC_HW_FEAT_TSSEL) >> 12;
> -	/* 802.3az - Energy-Efficient Ethernet (EEE) */
> -	dma_cap->eee = (hw_cap & GMAC_HW_FEAT_EEESEL) >> 13;
>   	/* TX and RX csum */
> -	dma_cap->tx_coe = (hw_cap & GMAC_HW_FEAT_TXCOSEL) >> 14;
>   	dma_cap->rx_coe =  (hw_cap & GMAC_HW_FEAT_RXCOESEL) >> 16;
> -	dma_cap->vlins = (hw_cap & GMAC_HW_FEAT_SAVLANINS) >> 27;
> +	dma_cap->tx_coe = (hw_cap & GMAC_HW_FEAT_TXCOSEL) >> 14;
> +	/* 802.3az - Energy-Efficient Ethernet (EEE) */
> +	dma_cap->eee = (hw_cap & GMAC_HW_FEAT_EEESEL) >> 13;
> +	/* IEEE 1588-2008 */
> +	dma_cap->atime_stamp = (hw_cap & GMAC_HW_FEAT_TSSEL) >> 12;
>   	dma_cap->arpoffsel = (hw_cap & GMAC_HW_FEAT_ARPOFFSEL) >> 9;
> +	/* MMC */
> +	dma_cap->rmon = (hw_cap & GMAC_HW_FEAT_MMCSEL) >> 8;
> +	dma_cap->pmt_magic_frame = (hw_cap & GMAC_HW_FEAT_MGKSEL) >> 7;
> +	dma_cap->pmt_remote_wake_up = (hw_cap & GMAC_HW_FEAT_RWKSEL) >> 6;
> +	dma_cap->sma_mdio = (hw_cap & GMAC_HW_FEAT_SMASEL) >> 5;
> +	dma_cap->vlhash = (hw_cap & GMAC_HW_FEAT_VLHASH) >> 4;
> +	dma_cap->pcs = (hw_cap & GMAC_HW_FEAT_PCSSEL) >> 3;
> +	dma_cap->half_duplex = (hw_cap & GMAC_HW_FEAT_HDSEL) >> 2;
> +	dma_cap->mbps_1000 = (hw_cap & GMAC_HW_FEAT_GMIISEL) >> 1;
> +	dma_cap->mbps_10_100 = (hw_cap & GMAC_HW_FEAT_MIISEL);
>   
>   	/* MAC HW feature1 */
>   	hw_cap = readl(ioaddr + GMAC_HW_FEATURE1);
> @@ -408,7 +408,6 @@ static int dwmac4_get_hw_feature(void __iomem *ioaddr,
>   	dma_cap->av = (hw_cap & GMAC_HW_FEAT_AVSEL) >> 20;
>   	dma_cap->tsoen = (hw_cap & GMAC_HW_TSOEN) >> 18;
>   	dma_cap->sphen = (hw_cap & GMAC_HW_FEAT_SPHEN) >> 17;
> -
>   	dma_cap->addr64 = (hw_cap & GMAC_HW_ADDR64) >> 14;
>   	switch (dma_cap->addr64) {
>   	case 0:
> @@ -424,31 +423,30 @@ static int dwmac4_get_hw_feature(void __iomem *ioaddr,
>   		dma_cap->addr64 = 32;
>   		break;
>   	}
> -
>   	/* RX and TX FIFO sizes are encoded as log2(n / 128). Undo that by
>   	 * shifting and store the sizes in bytes.
>   	 */
>   	dma_cap->tx_fifo_size = 128 << ((hw_cap & GMAC_HW_TXFIFOSIZE) >> 6);
>   	dma_cap->rx_fifo_size = 128 << ((hw_cap & GMAC_HW_RXFIFOSIZE) >> 0);
> +
>   	/* MAC HW feature2 */
>   	hw_cap = readl(ioaddr + GMAC_HW_FEATURE2);
> +	/* Number of Auxiliary Snapshot Inputs */
> +	dma_cap->aux_snapshot_n = (hw_cap & GMAC_HW_FEAT_AUXSNAPNUM) >> 28;
> +	/* PPS output */
> +	dma_cap->pps_out_num = (hw_cap & GMAC_HW_FEAT_PPSOUTNUM) >> 24;
>   	/* TX and RX number of channels */
> -	dma_cap->number_rx_channel =
> -		((hw_cap & GMAC_HW_FEAT_RXCHCNT) >> 12) + 1;
>   	dma_cap->number_tx_channel =
>   		((hw_cap & GMAC_HW_FEAT_TXCHCNT) >> 18) + 1;
> +	dma_cap->number_rx_channel =
> +		((hw_cap & GMAC_HW_FEAT_RXCHCNT) >> 12) + 1;
>   	/* TX and RX number of queues */
> -	dma_cap->number_rx_queues =
> -		((hw_cap & GMAC_HW_FEAT_RXQCNT) >> 0) + 1;
>   	dma_cap->number_tx_queues =
>   		((hw_cap & GMAC_HW_FEAT_TXQCNT) >> 6) + 1;
> -	/* PPS output */
> -	dma_cap->pps_out_num = (hw_cap & GMAC_HW_FEAT_PPSOUTNUM) >> 24;
> -
> +	dma_cap->number_rx_queues =
> +		((hw_cap & GMAC_HW_FEAT_RXQCNT) >> 0) + 1;
>   	/* IEEE 1588-2002 */
>   	dma_cap->time_stamp = 0;
> -	/* Number of Auxiliary Snapshot Inputs */
> -	dma_cap->aux_snapshot_n = (hw_cap & GMAC_HW_FEAT_AUXSNAPNUM) >> 28;
>   
>   	/* MAC HW feature3 */
>   	hw_cap = readl(ioaddr + GMAC_HW_FEATURE3);