Re: [PATCH v3 4/4] drivers: net: Add APM X-Gene SoC ethernet driver support.

[Joe Perches <joe@perches.com>]

On Wed, 2014-04-16 at 19:39 -0700, Iyappan Subramanian wrote:
> This patch adds network driver for APM X-Gene SoC ethernet.
[]
> diff --git a/drivers/net/ethernet/apm/xgene/Kconfig b/drivers/net/ethernet/apm/xgene/Kconfig
[]
> @@ -0,0 +1,10 @@
> +config NET_XGENE
> +	tristate "APM X-Gene SoC Ethernet Driver"
> +	select PHYLIB
> +	default y

default y? 

Shouldn't this need a depends on too?

> diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_hw.c b/drivers/net/ethernet/apm/xgene/xgene_enet_hw.c

> +static void xgene_enet_ring_set_type(u32 *ring_cfg, u8 is_bufpool)
> +{

bool is_bufpool?

> +static void xgene_enet_set_ring_id(struct xgene_enet_desc_ring *ring)
> +{
> +	u32 ring_id_val;
> +	u32 ring_id_buf;
> +	u8 is_bufpool = IS_FP(ring->id);

bool?

> +
> +	ring_id_val = ring->id & GENMASK(9, 0);
> +	ring_id_val |= (1 << 31) & GENMASK(31, 31);

Setting a single bit and masking with the same
bit looks silly.

> +
> +	ring_id_buf = (ring->num << 9) & GENMASK(18, 9);
> +	ring_id_buf |= ((u32) is_bufpool << 20) & GENMASK(20, 20);

And here.

> +	ring_id_buf |= (1U << 21) & GENMASK(21, 21);

This too.

[]

> +static void xgene_enet_rd_mcx_stats(struct xgene_enet_pdata *pdata,
> +				    u32 rd_addr, u32 *rd_data)
> +{
[]
> +	if (!ret)
> +		netdev_err(pdata->ndev, "MCX stats read failed, addr: %04x",
> +			   rd_addr);

Missing newline

> +/* Start Statistics related functions */
> +static void xgene_gmac_get_rx_stats(struct xgene_enet_pdata *pdata,
> +				    struct xgene_enet_rx_stats *rx_stat)
> +{
> +	xgene_enet_rd_mcx_stats(pdata, RBYT_ADDR, &rx_stat->rx_byte_count);
> +	xgene_enet_rd_mcx_stats(pdata, RPKT_ADDR, &rx_stat->rx_packet_count);
> +	xgene_enet_rd_mcx_stats(pdata, RDRP_ADDR, &rx_stat->rx_drop_pkt_count);
> +	xgene_enet_rd_mcx_stats(pdata, RFCS_ADDR, &rx_stat->rx_fcs_err_count);
> +	xgene_enet_rd_mcx_stats(pdata, RFLR_ADDR,
> +				&rx_stat->rx_frm_len_err_pkt_count);
> +	xgene_enet_rd_mcx_stats(pdata, RALN_ADDR,
> +				&rx_stat->rx_alignment_err_pkt_count);
> +	xgene_enet_rd_mcx_stats(pdata, ROVR_ADDR,
> +				&rx_stat->rx_oversize_pkt_count);
> +	xgene_enet_rd_mcx_stats(pdata, RUND_ADDR,
> +				&rx_stat->rx_undersize_pkt_count);
> +
> +	rx_stat->rx_byte_count &= RX_BYTE_CNTR_MASK;
> +	rx_stat->rx_packet_count &= RX_PKT_CNTR_MASK;
> +	rx_stat->rx_drop_pkt_count &= RX_DROPPED_PKT_CNTR_MASK;
> +	rx_stat->rx_fcs_err_count &= RX_FCS_ERROR_CNTR_MASK;
> +	rx_stat->rx_frm_len_err_pkt_count &= RX_LEN_ERR_CNTR_MASK;
> +	rx_stat->rx_alignment_err_pkt_count &= RX_ALIGN_ERR_CNTR_MASK;
> +	rx_stat->rx_oversize_pkt_count &= RX_OVRSIZE_PKT_CNTR_MASK;
> +	rx_stat->rx_undersize_pkt_count &= RX_UNDRSIZE_PKT_CNTR_MASK;
> +}
> +
> +static void xgene_gmac_get_tx_stats(struct xgene_enet_pdata *pdata,
> +				    struct xgene_enet_tx_stats *tx_stats)
> +{
> +	xgene_enet_rd_mcx_stats(pdata, TBYT_ADDR, &tx_stats->tx_byte_count);
> +	xgene_enet_rd_mcx_stats(pdata, TPKT_ADDR, &tx_stats->tx_pkt_count);
> +	xgene_enet_rd_mcx_stats(pdata, TDRP_ADDR, &tx_stats->tx_drop_frm_count);
> +	xgene_enet_rd_mcx_stats(pdata, TFCS_ADDR,
> +				&tx_stats->tx_fcs_err_frm_count);
> +	xgene_enet_rd_mcx_stats(pdata, TUND_ADDR,
> +				&tx_stats->tx_undersize_frm_count);
> +
> +	tx_stats->tx_byte_count &= TX_BYTE_CNTR_MASK;
> +	tx_stats->tx_pkt_count &= TX_PKT_CNTR_MASK;
> +	tx_stats->tx_drop_frm_count &= TX_DROP_FRAME_CNTR_MASK;
> +	tx_stats->tx_fcs_err_frm_count &= TX_FCS_ERROR_CNTR_MASK;
> +	tx_stats->tx_undersize_frm_count &= TX_UNDSIZE_FRAME_CNTR_MASK;
> +}

Pity about the masks


> +#define RX_BYTE_CNTR_MASK		0x7fffffff
> +#define RX_PKT_CNTR_MASK		0x7fffffff
> +#define RX_FCS_ERROR_CNTR_MASK		0x0000ffff
> +#define RX_ALIGN_ERR_CNTR_MASK		0x0000ffff
> +#define RX_LEN_ERR_CNTR_MASK		0x0000ffff
> +#define RX_UNDRSIZE_PKT_CNTR_MASK	0x0000ffff
> +#define RX_OVRSIZE_PKT_CNTR_MASK	0x0000ffff
> +#define RX_DROPPED_PKT_CNTR_MASK	0x0000ffff
> +#define TX_BYTE_CNTR_MASK		0x7fffffff
> +#define TX_PKT_CNTR_MASK		0x7fffffff
> +#define TX_DROP_FRAME_CNTR_MASK		0x0000ffff
> +#define TX_FCS_ERROR_CNTR_MASK		0x00000fff
> +#define TX_UNDSIZE_FRAME_CNTR_MASK	0x00000fff

Any of these going to possibly overrun their
counter size between polls?

[]
> +static struct xgene_enet_desc_ring *xgene_enet_create_desc_ring(
> +			struct net_device *ndev, u32 ring_num,
> +			enum xgene_enet_ring_cfgsize cfgsize, u32 ring_id)
> +{
> +	struct xgene_enet_desc_ring *ring;
> +	struct xgene_enet_pdata *pdata = netdev_priv(ndev);
> +	struct device *dev = &pdata->pdev->dev;
> +	u32 size;
> +
> +	ring = devm_kzalloc(dev, sizeof(struct xgene_enet_desc_ring),
> +			    GFP_KERNEL);
> +	if (!ring) {
> +		netdev_err(ndev, "Could not allocate ring\n");

Unnecessary OOM.  alloc errors get a generic OOM and dump_stack()


> +static struct net_device_stats *xgene_enet_stats(struct net_device *ndev)
> +{
> +	struct xgene_enet_pdata *pdata = netdev_priv(ndev);
> +	struct net_device_stats *nst = &pdata->nstats;
> +	struct xgene_enet_detailed_stats detailed_stats;
> +	struct xgene_enet_rx_stats *rx_stats;
> +	struct xgene_enet_tx_stats *tx_stats;
> +	u32 pkt_bytes, crc_bytes = 4;
> +
> +	memset(&detailed_stats, 0, sizeof(struct xgene_enet_detailed_stats));
> +
> +	rx_stats = &detailed_stats.rx_stats;
> +	tx_stats = &detailed_stats.tx_stats;
> +
> +	local_irq_disable();
> +	xgene_gmac_get_detailed_stats(pdata, &detailed_stats);
> +
> +	pkt_bytes = rx_stats->rx_byte_count;
> +	pkt_bytes -= rx_stats->rx_packet_count * crc_bytes;
> +	nst->rx_packets += rx_stats->rx_packet_count;
> +	nst->rx_bytes += pkt_bytes;
> +
> +	pkt_bytes = tx_stats->tx_byte_count;
> +	pkt_bytes -= tx_stats->tx_pkt_count * crc_bytes;
> +	nst->tx_packets += tx_stats->tx_pkt_count;
> +	nst->tx_bytes += pkt_bytes;
> +
> +	nst->rx_dropped += rx_stats->rx_drop_pkt_count;
> +	nst->tx_dropped += tx_stats->tx_drop_frm_count;
> +
> +	nst->rx_crc_errors += rx_stats->rx_fcs_err_count;
> +	nst->rx_length_errors += rx_stats->rx_frm_len_err_pkt_count;
> +	nst->rx_frame_errors += rx_stats->rx_alignment_err_pkt_count;
> +	nst->rx_over_errors += rx_stats->rx_oversize_pkt_count;
> +
> +	nst->rx_errors += rx_stats->rx_fcs_err_count
> +	    + rx_stats->rx_frm_len_err_pkt_count
> +	    + rx_stats->rx_oversize_pkt_count
> +	    + rx_stats->rx_undersize_pkt_count;
> +
> +	nst->tx_errors += tx_stats->tx_fcs_err_frm_count +
> +	    tx_stats->tx_undersize_frm_count;
> +
> +	local_irq_enable();
> +
> +	return nst;
> +}