[PATCH v2 RFC net-next 12/18] net: mvpp2: add RXQ flow control configurations

stefanc
2021-01-24T11:57:42Z

This patch add RXQ flow control configurations.
Patch do not enable flow control itself, flow control
disabled by default.

Signed-off-by: Stefan Chulski <stefanc@marvell.com>
---
drivers/net/ethernet/marvell/mvpp2/mvpp2.h | 40 ++++++-
drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 111 ++++++++++++++++++++
2 files changed, 147 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
index 4c8e422..ba57465 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
@@ -763,10 +763,39 @@
((kb) * 1024 - MVPP2_TX_FIFO_THRESHOLD_MIN)

/* MSS Flow control */
-#define MSS_SRAM_SIZE 0x800
-#define FC_QUANTA 0xFFFF
-#define FC_CLK_DIVIDER 0x140
-#define MSS_THRESHOLD_STOP 768
+#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 0x140
+
+#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 \
@@ -1191,6 +1220,9 @@ 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 d79c687..2407c52 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -744,6 +744,110 @@ 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.
+ */
+ 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,
@@ -3007,6 +3111,9 @@ 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 */
@@ -3019,6 +3126,10 @@ 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:
--
1.9.1