Re: [PATCH v7 net-next 10/15] net: mvpp2: add RXQ flow control configurations
From: Marcin Wojtas
Date: Thu Feb 04 2021 - 14:12:54 EST
Hi,
wt., 2 lut 2021 o 09:18 <stefanc@xxxxxxxxxxx> napisał(a):
>
> From: Stefan Chulski <stefanc@xxxxxxxxxxx>
>
> This patch adds RXQ flow control configurations.
> Flow control disabled by default.
> Minimum ring size limited to 1024 descriptors.
>
> Signed-off-by: Stefan Chulski <stefanc@xxxxxxxxxxx>
> ---
> drivers/net/ethernet/marvell/mvpp2/mvpp2.h | 35 +++++-
> drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 116 ++++++++++++++++++++
> 2 files changed, 150 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
> index e010410..0f27be0 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
> @@ -766,9 +766,36 @@
> #define MSS_SRAM_SIZE 0x800
> #define MSS_FC_COM_REG 0
> #define FLOW_CONTROL_ENABLE_BIT BIT(0)
> +#define FLOW_CONTROL_UPDATE_COMMAND_BIT BIT(31)
> #define FC_QUANTA 0xFFFF
> #define FC_CLK_DIVIDER 100
> -#define MSS_THRESHOLD_STOP 768
> +
> +#define MSS_RXQ_TRESH_BASE 0x200
> +#define MSS_RXQ_TRESH_OFFS 4
> +#define MSS_RXQ_TRESH_REG(q, fq) (MSS_RXQ_TRESH_BASE + (((q) + (fq)) \
> + * MSS_RXQ_TRESH_OFFS))
> +
> +#define MSS_RXQ_TRESH_START_MASK 0xFFFF
> +#define MSS_RXQ_TRESH_STOP_MASK (0xFFFF << MSS_RXQ_TRESH_STOP_OFFS)
> +#define MSS_RXQ_TRESH_STOP_OFFS 16
> +
> +#define MSS_RXQ_ASS_BASE 0x80
> +#define MSS_RXQ_ASS_OFFS 4
> +#define MSS_RXQ_ASS_PER_REG 4
> +#define MSS_RXQ_ASS_PER_OFFS 8
> +#define MSS_RXQ_ASS_PORTID_OFFS 0
> +#define MSS_RXQ_ASS_PORTID_MASK 0x3
> +#define MSS_RXQ_ASS_HOSTID_OFFS 2
> +#define MSS_RXQ_ASS_HOSTID_MASK 0x3F
> +
> +#define MSS_RXQ_ASS_Q_BASE(q, fq) ((((q) + (fq)) % MSS_RXQ_ASS_PER_REG) \
> + * MSS_RXQ_ASS_PER_OFFS)
> +#define MSS_RXQ_ASS_PQ_BASE(q, fq) ((((q) + (fq)) / MSS_RXQ_ASS_PER_REG) \
> + * MSS_RXQ_ASS_OFFS)
> +#define MSS_RXQ_ASS_REG(q, fq) (MSS_RXQ_ASS_BASE + MSS_RXQ_ASS_PQ_BASE(q, fq))
> +
> +#define MSS_THRESHOLD_STOP 768
> +#define MSS_THRESHOLD_START 1024
>
> /* RX buffer constants */
> #define MVPP2_SKB_SHINFO_SIZE \
> @@ -1026,6 +1053,9 @@ struct mvpp2 {
>
> /* Global TX Flow Control config */
> bool global_tx_fc;
> +
> + /* Spinlocks for CM3 shared memory configuration */
> + spinlock_t mss_spinlock;
> };
>
> struct mvpp2_pcpu_stats {
> @@ -1188,6 +1218,9 @@ struct mvpp2_port {
> bool rx_hwtstamp;
> enum hwtstamp_tx_types tx_hwtstamp_type;
> struct mvpp2_hwtstamp_queue tx_hwtstamp_queue[2];
> +
> + /* Firmware TX flow control */
> + bool tx_fc;
> };
>
> /* The mvpp2_tx_desc and mvpp2_rx_desc structures describe the
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index 770f45a..d778ae1 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -742,6 +742,110 @@ static void *mvpp2_buf_alloc(struct mvpp2_port *port,
> return data;
> }
>
> +/* Routine enable flow control for RXQs condition */
> +static void mvpp2_rxq_enable_fc(struct mvpp2_port *port)
> +{
> + int val, cm3_state, host_id, q;
> + int fq = port->first_rxq;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&port->priv->mss_spinlock, flags);
> +
> + /* Remove Flow control enable bit to prevent race between FW and Kernel
> + * If Flow control were enabled, it would be re-enabled.
Nit:
s/were/was/
Thanks,
Marcin
> + */
> + val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
> + cm3_state = (val & FLOW_CONTROL_ENABLE_BIT);
> + val &= ~FLOW_CONTROL_ENABLE_BIT;
> + mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
> +
> + /* Set same Flow control for all RXQs */
> + for (q = 0; q < port->nrxqs; q++) {
> + /* Set stop and start Flow control RXQ thresholds */
> + val = MSS_THRESHOLD_START;
> + val |= (MSS_THRESHOLD_STOP << MSS_RXQ_TRESH_STOP_OFFS);
> + mvpp2_cm3_write(port->priv, MSS_RXQ_TRESH_REG(q, fq), val);
> +
> + val = mvpp2_cm3_read(port->priv, MSS_RXQ_ASS_REG(q, fq));
> + /* Set RXQ port ID */
> + val &= ~(MSS_RXQ_ASS_PORTID_MASK << MSS_RXQ_ASS_Q_BASE(q, fq));
> + val |= (port->id << MSS_RXQ_ASS_Q_BASE(q, fq));
> + val &= ~(MSS_RXQ_ASS_HOSTID_MASK << (MSS_RXQ_ASS_Q_BASE(q, fq)
> + + MSS_RXQ_ASS_HOSTID_OFFS));
> +
> + /* Calculate RXQ host ID:
> + * In Single queue mode: Host ID equal to Host ID used for
> + * shared RX interrupt
> + * In Multi queue mode: Host ID equal to number of
> + * RXQ ID / number of CoS queues
> + * In Single resource mode: Host ID always equal to 0
> + */
> + if (queue_mode == MVPP2_QDIST_SINGLE_MODE)
> + host_id = port->nqvecs;
> + else if (queue_mode == MVPP2_QDIST_MULTI_MODE)
> + host_id = q;
> + else
> + host_id = 0;
> +
> + /* Set RXQ host ID */
> + val |= (host_id << (MSS_RXQ_ASS_Q_BASE(q, fq)
> + + MSS_RXQ_ASS_HOSTID_OFFS));
> +
> + mvpp2_cm3_write(port->priv, MSS_RXQ_ASS_REG(q, fq), val);
> + }
> +
> + /* Notify Firmware that Flow control config space ready for update */
> + val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
> + val |= FLOW_CONTROL_UPDATE_COMMAND_BIT;
> + val |= cm3_state;
> + mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
> +
> + spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
> +}
> +
> +/* Routine disable flow control for RXQs condition */
> +static void mvpp2_rxq_disable_fc(struct mvpp2_port *port)
> +{
> + int val, cm3_state, q;
> + unsigned long flags;
> + int fq = port->first_rxq;
> +
> + spin_lock_irqsave(&port->priv->mss_spinlock, flags);
> +
> + /* Remove Flow control enable bit to prevent race between FW and Kernel
> + * If Flow control were enabled, it would be re-enabled.
> + */
> + val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
> + cm3_state = (val & FLOW_CONTROL_ENABLE_BIT);
> + val &= ~FLOW_CONTROL_ENABLE_BIT;
> + mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
> +
> + /* Disable Flow control for all RXQs */
> + for (q = 0; q < port->nrxqs; q++) {
> + /* Set threshold 0 to disable Flow control */
> + val = 0;
> + val |= (0 << MSS_RXQ_TRESH_STOP_OFFS);
> + mvpp2_cm3_write(port->priv, MSS_RXQ_TRESH_REG(q, fq), val);
> +
> + val = mvpp2_cm3_read(port->priv, MSS_RXQ_ASS_REG(q, fq));
> +
> + val &= ~(MSS_RXQ_ASS_PORTID_MASK << MSS_RXQ_ASS_Q_BASE(q, fq));
> +
> + val &= ~(MSS_RXQ_ASS_HOSTID_MASK << (MSS_RXQ_ASS_Q_BASE(q, fq)
> + + MSS_RXQ_ASS_HOSTID_OFFS));
> +
> + mvpp2_cm3_write(port->priv, MSS_RXQ_ASS_REG(q, fq), val);
> + }
> +
> + /* Notify Firmware that Flow control config space ready for update */
> + val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
> + val |= FLOW_CONTROL_UPDATE_COMMAND_BIT;
> + val |= cm3_state;
> + mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
> +
> + spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
> +}
> +
> /* Release buffer to BM */
> static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
> dma_addr_t buf_dma_addr,
> @@ -3006,6 +3110,9 @@ static void mvpp2_cleanup_rxqs(struct mvpp2_port *port)
>
> for (queue = 0; queue < port->nrxqs; queue++)
> mvpp2_rxq_deinit(port, port->rxqs[queue]);
> +
> + if (port->tx_fc)
> + mvpp2_rxq_disable_fc(port);
> }
>
> /* Init all Rx queues for port */
> @@ -3018,6 +3125,10 @@ static int mvpp2_setup_rxqs(struct mvpp2_port *port)
> if (err)
> goto err_cleanup;
> }
> +
> + if (port->tx_fc)
> + mvpp2_rxq_enable_fc(port);
> +
> return 0;
>
> err_cleanup:
> @@ -4317,6 +4428,8 @@ static int mvpp2_check_ringparam_valid(struct net_device *dev,
>
> if (ring->rx_pending > MVPP2_MAX_RXD_MAX)
> new_rx_pending = MVPP2_MAX_RXD_MAX;
> + else if (ring->rx_pending < MSS_THRESHOLD_START)
> + new_rx_pending = MSS_THRESHOLD_START;
> else if (!IS_ALIGNED(ring->rx_pending, 16))
> new_rx_pending = ALIGN(ring->rx_pending, 16);
>
> @@ -7170,6 +7283,9 @@ static int mvpp2_probe(struct platform_device *pdev)
> priv->hw_version = MVPP23;
> }
>
> + /* Init mss lock */
> + spin_lock_init(&priv->mss_spinlock);
> +
> /* Initialize network controller */
> err = mvpp2_init(pdev, priv);
> if (err < 0) {
> --
> 1.9.1
>