Re: [PATCH 2/4] net: ethernet: ti: cpsw: add multi queue support

From: Grygorii Strashko
Date: Fri Jul 08 2016 - 09:12:57 EST


On 06/30/2016 10:04 PM, Ivan Khoronzhuk wrote:
> The cpsw h/w supports up to 8 tx and 8 rx channels.This patch adds
> multi-queue support to the driver. An ability to configure h/w
> shaper will be added with separate patch. Default shaper mode, as
> before, priority mode.
>
> The poll function handles all unprocessed channels, till all of
> them are free, beginning from hi priority channel.
>
> The statistic for every channel can be read with:
> ethtool -S ethX
>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
> ---
> drivers/net/ethernet/ti/cpsw.c | 334 +++++++++++++++++++++-----------
> drivers/net/ethernet/ti/davinci_cpdma.c | 12 ++
> drivers/net/ethernet/ti/davinci_cpdma.h | 2 +
> 3 files changed, 237 insertions(+), 111 deletions(-)
>
> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> index a713336..14d53eb 100644
> --- a/drivers/net/ethernet/ti/cpsw.c
> +++ b/drivers/net/ethernet/ti/cpsw.c
> @@ -140,6 +140,8 @@ do { \
> #define CPSW_CMINTMAX_INTVL (1000 / CPSW_CMINTMIN_CNT)
> #define CPSW_CMINTMIN_INTVL ((1000 / CPSW_CMINTMAX_CNT) + 1)
>
> +#define CPSW_MAX_QUEUES 8
> +
> #define cpsw_slave_index(priv) \
> ((priv->data.dual_emac) ? priv->emac_port : \
> priv->data.active_slave)
> @@ -383,7 +385,8 @@ struct cpsw_priv {
> u8 mac_addr[ETH_ALEN];
> struct cpsw_slave *slaves;
> struct cpdma_ctlr *dma;
> - struct cpdma_chan *txch, *rxch;
> + struct cpdma_chan *txch[CPSW_MAX_QUEUES];
> + struct cpdma_chan *rxch[CPSW_MAX_QUEUES];
> struct cpsw_ale *ale;
> bool rx_pause;
> bool tx_pause;
> @@ -395,6 +398,7 @@ struct cpsw_priv {
> u32 num_irqs;
> struct cpts *cpts;
> u32 emac_port;
> + int rx_ch_num, tx_ch_num;
> };
>

[...]

>
> @@ -989,26 +1024,50 @@ update_return:
>
> static int cpsw_get_sset_count(struct net_device *ndev, int sset)
> {
> + struct cpsw_priv *priv = netdev_priv(ndev);
> +
> switch (sset) {
> case ETH_SS_STATS:
> - return CPSW_STATS_LEN;
> + return (CPSW_STATS_COMMON_LEN +
> + (priv->rx_ch_num + priv->tx_ch_num) *
> + CPSW_STATS_CH_LEN);
> default:
> return -EOPNOTSUPP;
> }
> }
>
> +static void cpsw_add_ch_strings(u8 **p, int ch_num, int rx_dir)
> +{
> + int ch_stats_len;
> + int line;
> + int i;
> +
> + ch_stats_len = CPSW_STATS_CH_LEN * ch_num;
> + for (i = 0; i < ch_stats_len; i++) {
> + line = i % CPSW_STATS_CH_LEN;
> + sprintf(*p, "%s DMA chan %d: %s", rx_dir ? "Rx" : "Tx",
> + i / CPSW_STATS_CH_LEN,

snprintf(,ETH_GSTRING_LEN,) ?

> + cpsw_gstrings_ch_stats[line].stat_string);
> + *p += ETH_GSTRING_LEN;
> + }
> +}
> +
> static void cpsw_get_strings(struct net_device *ndev, u32 stringset, u8 *data)
> {
> + struct cpsw_priv *priv = netdev_priv(ndev);
> u8 *p = data;
> int i;
>
> switch (stringset) {
> case ETH_SS_STATS:
> - for (i = 0; i < CPSW_STATS_LEN; i++) {
> + for (i = 0; i < CPSW_STATS_COMMON_LEN; i++) {
> memcpy(p, cpsw_gstrings_stats[i].stat_string,
> ETH_GSTRING_LEN);
> p += ETH_GSTRING_LEN;
> }
> +
> + cpsw_add_ch_strings(&p, priv->rx_ch_num, 1);
> + cpsw_add_ch_strings(&p, priv->tx_ch_num, 0);
> break;
> }
> }
> @@ -1017,35 +1076,38 @@ static void cpsw_get_ethtool_stats(struct net_device *ndev,
> struct ethtool_stats *stats, u64 *data)
> {
> struct cpsw_priv *priv = netdev_priv(ndev);
> - struct cpdma_chan_stats rx_stats;
> - struct cpdma_chan_stats tx_stats;
> - u32 val;
> + struct cpdma_chan_stats ch_stats;
> + int i, l, ch, ret;
> u8 *p;
> - int i;
> +
> + ret = pm_runtime_get_sync(&priv->pdev->dev);
> + if (ret < 0) {
> + pm_runtime_put_noidle(&priv->pdev->dev);
> + return;
> + }

You probably need to base you work on top of net-next.git

>
> /* Collect Davinci CPDMA stats for Rx and Tx Channel */
> - cpdma_chan_get_stats(priv->rxch, &rx_stats);
> - cpdma_chan_get_stats(priv->txch, &tx_stats);
> -
> - for (i = 0; i < CPSW_STATS_LEN; i++) {
> - switch (cpsw_gstrings_stats[i].type) {
> - case CPSW_STATS:
> - val = readl(priv->hw_stats +
> - cpsw_gstrings_stats[i].stat_offset);
> - data[i] = val;
> - break;
> + for (l = 0; l < CPSW_STATS_COMMON_LEN; l++)
> + data[l] = readl(priv->hw_stats +
> + cpsw_gstrings_stats[l].stat_offset);
>
> - case CPDMA_RX_STATS:
> - p = (u8 *)&rx_stats +
> - cpsw_gstrings_stats[i].stat_offset;
> - data[i] = *(u32 *)p;
> - break;
> + pm_runtime_put(&priv->pdev->dev);
>
> - case CPDMA_TX_STATS:
> - p = (u8 *)&tx_stats +
> - cpsw_gstrings_stats[i].stat_offset;
> - data[i] = *(u32 *)p;
> - break;
> + for (ch = 0; ch < priv->rx_ch_num; ch++) {
> + cpdma_chan_get_stats(priv->rxch[ch], &ch_stats);
> + for (i = 0; i < CPSW_STATS_CH_LEN; i++, l++) {
> + p = (u8 *)&ch_stats +
> + cpsw_gstrings_ch_stats[i].stat_offset;
> + data[l] = *(u32 *)p;
> + }
> + }
> +
> + for (ch = 0; ch < priv->tx_ch_num; ch++) {
> + cpdma_chan_get_stats(priv->txch[ch], &ch_stats);
> + for (i = 0; i < CPSW_STATS_CH_LEN; i++, l++) {
> + p = (u8 *)&ch_stats +
> + cpsw_gstrings_ch_stats[i].stat_offset;
> + data[l] = *(u32 *)p;
> }
> }

I think, it's better to do pm_runtime_put() here even if now cpdma does'n access
HW from cpdma_chan_get_stats it may change in fufture.
And it's not critical from PM point of view

> }
> @@ -1065,19 +1127,29 @@ static int cpsw_common_res_usage_state(struct cpsw_priv *priv)
> return usage_count;
> }
>
> +static inline struct cpdma_chan *
> +cpsw_tx_queue_mapping(struct cpsw_priv *priv, struct sk_buff *skb)
> +{
> + unsigned int q_idx = skb_get_queue_mapping(skb);
> +
> + if (q_idx >= priv->tx_ch_num)
> + q_idx = q_idx % priv->tx_ch_num;
> +
> + return priv->txch[q_idx];
> +}
> +
> static inline int cpsw_tx_packet_submit(struct net_device *ndev,
> - struct cpsw_priv *priv, struct sk_buff *skb)
> + struct cpsw_priv *priv,
> + struct sk_buff *skb,
> + struct cpdma_chan *txch)
> {
> if (!priv->data.dual_emac)
> - return cpdma_chan_submit(priv->txch, skb, skb->data,
> - skb->len, 0);
> + return cpdma_chan_submit(txch, skb, skb->data, skb->len, 0);
>
> if (ndev == cpsw_get_slave_ndev(priv, 0))
> - return cpdma_chan_submit(priv->txch, skb, skb->data,
> - skb->len, 1);
> + return cpdma_chan_submit(txch, skb, skb->data, skb->len, 1);
> else
> - return cpdma_chan_submit(priv->txch, skb, skb->data,
> - skb->len, 2);
> + return cpdma_chan_submit(txch, skb, skb->data, skb->len, 2);
> }
>
> static inline void cpsw_add_dual_emac_def_ale_entries(

[...]

>
> @@ -1614,12 +1713,16 @@ static int cpsw_ndo_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
> static void cpsw_ndo_tx_timeout(struct net_device *ndev)
> {
> struct cpsw_priv *priv = netdev_priv(ndev);
> + int ch;
>
> cpsw_err(priv, tx_err, "transmit timeout, restarting dma\n");
> ndev->stats.tx_errors++;
> cpsw_intr_disable(priv);
> - cpdma_chan_stop(priv->txch);
> - cpdma_chan_start(priv->txch);
> + for (ch = 0; ch < priv->tx_ch_num; ch++) {
> + cpdma_chan_stop(priv->txch[ch]);
> + cpdma_chan_start(priv->txch[ch]);
> + }
> +
> cpsw_intr_enable(priv);
> }
>
> @@ -1833,7 +1936,7 @@ static void cpsw_get_drvinfo(struct net_device *ndev,
> struct cpsw_priv *priv = netdev_priv(ndev);
>
> strlcpy(info->driver, "cpsw", sizeof(info->driver));
> - strlcpy(info->version, "1.0", sizeof(info->version));
> + strlcpy(info->version, "1.1", sizeof(info->version));

Not sure about this change, at least not as part of this patch.

> strlcpy(info->bus_info, priv->pdev->name, sizeof(info->bus_info));
> }
>
> @@ -2181,7 +2284,7 @@ static int cpsw_probe_dual_emac(struct platform_device *pdev,
> struct cpsw_priv *priv_sl2;
> int ret = 0, i;
>
> - ndev = alloc_etherdev(sizeof(struct cpsw_priv));
> + ndev = alloc_etherdev_mq(sizeof(struct cpsw_priv), CPSW_MAX_QUEUES);
> if (!ndev) {
> dev_err(&pdev->dev, "cpsw: error allocating net_device\n");
> return -ENOMEM;
> @@ -2216,8 +2319,15 @@ static int cpsw_probe_dual_emac(struct platform_device *pdev,
> priv_sl2->wr_regs = priv->wr_regs;
> priv_sl2->hw_stats = priv->hw_stats;
> priv_sl2->dma = priv->dma;
> - priv_sl2->txch = priv->txch;
> - priv_sl2->rxch = priv->rxch;

[...]

>
> - if (WARN_ON(!priv->txch || !priv->rxch)) {
> + if (WARN_ON(!priv->rxch[0] || !priv->txch[0])) {
> dev_err(priv->dev, "error initializing dma channels\n");
> ret = -ENOMEM;
> goto clean_dma_ret;
> diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c b/drivers/net/ethernet/ti/davinci_cpdma.c
> index 2f4b571..a4b299d 100644
> --- a/drivers/net/ethernet/ti/davinci_cpdma.c
> +++ b/drivers/net/ethernet/ti/davinci_cpdma.c
> @@ -481,6 +481,18 @@ void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr, u32 value)
> }
> EXPORT_SYMBOL_GPL(cpdma_ctlr_eoi);
>
> +u32 cpdma_ctrl_rxchs_state(struct cpdma_ctlr *ctlr)
> +{
> + return dma_reg_read(ctlr, CPDMA_RXINTSTATMASKED);
> +}
> +EXPORT_SYMBOL_GPL(cpdma_ctrl_rxchs_state);
> +
> +u32 cpdma_ctrl_txchs_state(struct cpdma_ctlr *ctlr)
> +{
> + return dma_reg_read(ctlr, CPDMA_TXINTSTATMASKED);

TRM: CPDMA_INT TX INTERRUPT STATUS REGISTER (MASKED VALUE)

> +}
> +EXPORT_SYMBOL_GPL(cpdma_ctrl_txchs_state);

This is interrupt status, so may be cpdma_ctrl_tx[rx]chs_intr_status() name
will be more appropriate?

> +
> /**
> * cpdma_chan_split_pool - Splits ctrl pool between all channels.
> * Has to be called under ctlr lock
> diff --git a/drivers/net/ethernet/ti/davinci_cpdma.h b/drivers/net/ethernet/ti/davinci_cpdma.h
> index 0308b67..3ce91a1 100644
> --- a/drivers/net/ethernet/ti/davinci_cpdma.h
> +++ b/drivers/net/ethernet/ti/davinci_cpdma.h
> @@ -96,6 +96,8 @@ int cpdma_chan_process(struct cpdma_chan *chan, int quota);
> int cpdma_ctlr_int_ctrl(struct cpdma_ctlr *ctlr, bool enable);
> void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr, u32 value);
> int cpdma_chan_int_ctrl(struct cpdma_chan *chan, bool enable);
> +u32 cpdma_ctrl_rxchs_state(struct cpdma_ctlr *ctlr);
> +u32 cpdma_ctrl_txchs_state(struct cpdma_ctlr *ctlr);
> bool cpdma_check_free_tx_desc(struct cpdma_chan *chan);
>
> enum cpdma_control {
>


--
regards,
-grygorii