can: flexcan: make TX mailbox selectable during runtime

This patch makes the TX mailbox selectable duing runtime. This is a preparation
patch to use of the hardware FIFO selectable via runtime. As the TX mailbox
number is different in HW FIFO and normal mode.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 0a00a6d..1a7df29 100644 (file)
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -143,9 +143,9 @@
 
 /* FLEXCAN interrupt flag register (IFLAG) bits */
 /* Errata ERR005829 step7: Reserve first valid MB */
-#define FLEXCAN_TX_BUF_RESERVED                8
-#define FLEXCAN_TX_BUF_ID              9
-#define FLEXCAN_IFLAG_BUF(x)           BIT(x)
+#define FLEXCAN_TX_MB_RESERVED_OFF_FIFO        8
+#define FLEXCAN_TX_MB_OFF_FIFO         9
+#define FLEXCAN_IFLAG_MB(x)            BIT(x)
 #define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW BIT(7)
 #define FLEXCAN_IFLAG_RX_FIFO_WARN     BIT(6)
 #define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE        BIT(5)
@@ -256,6 +256,9 @@ struct flexcan_priv {
        struct napi_struct napi;
 
        struct flexcan_regs __iomem *regs;
+       struct flexcan_mb __iomem *tx_mb;
+       struct flexcan_mb __iomem *tx_mb_reserved;
+       u8 tx_mb_idx;
        u32 reg_esr;
        u32 reg_ctrl_default;
        u32 reg_imask1_default;
@@ -472,7 +475,6 @@ static int flexcan_get_berr_counter(const struct net_device *dev,
 static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
        const struct flexcan_priv *priv = netdev_priv(dev);
-       struct flexcan_regs __iomem *regs = priv->regs;
        struct can_frame *cf = (struct can_frame *)skb->data;
        u32 can_id;
        u32 data;
@@ -495,25 +497,25 @@ static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
        if (cf->can_dlc > 0) {
                data = be32_to_cpup((__be32 *)&cf->data[0]);
-               flexcan_write(data, &regs->mb[FLEXCAN_TX_BUF_ID].data[0]);
+               flexcan_write(data, &priv->tx_mb->data[0]);
        }
        if (cf->can_dlc > 3) {
                data = be32_to_cpup((__be32 *)&cf->data[4]);
-               flexcan_write(data, &regs->mb[FLEXCAN_TX_BUF_ID].data[1]);
+               flexcan_write(data, &priv->tx_mb->data[1]);
        }
 
        can_put_echo_skb(skb, dev, 0);
 
-       flexcan_write(can_id, &regs->mb[FLEXCAN_TX_BUF_ID].can_id);
-       flexcan_write(ctrl, &regs->mb[FLEXCAN_TX_BUF_ID].can_ctrl);
+       flexcan_write(can_id, &priv->tx_mb->can_id);
+       flexcan_write(ctrl, &priv->tx_mb->can_ctrl);
 
        /* Errata ERR005829 step8:
         * Write twice INACTIVE(0x8) code to first MB.
         */
        flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
-                     &regs->mb[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
+                     &priv->tx_mb_reserved->can_ctrl);
        flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
-                     &regs->mb[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
+                     &priv->tx_mb_reserved->can_ctrl);
 
        return NETDEV_TX_OK;
 }
@@ -750,7 +752,7 @@ static irqreturn_t flexcan_irq(int irq, void *dev_id)
        }
 
        /* transmission complete interrupt */
-       if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
+       if (reg_iflag1 & FLEXCAN_IFLAG_MB(priv->tx_mb_idx)) {
                handled = IRQ_HANDLED;
                stats->tx_bytes += can_get_echo_skb(dev, 0);
                stats->tx_packets++;
@@ -758,8 +760,8 @@ static irqreturn_t flexcan_irq(int irq, void *dev_id)
 
                /* after sending a RTR frame MB is in RX mode */
                flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
-                             &regs->mb[FLEXCAN_TX_BUF_ID].can_ctrl);
-               flexcan_write((1 << FLEXCAN_TX_BUF_ID), &regs->iflag1);
+                             &priv->tx_mb->can_ctrl);
+               flexcan_write(FLEXCAN_IFLAG_MB(priv->tx_mb_idx), &regs->iflag1);
                netif_wake_queue(dev);
        }
 
@@ -849,7 +851,7 @@ static int flexcan_chip_start(struct net_device *dev)
        reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
        reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT |
                FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN | FLEXCAN_MCR_SRX_DIS |
-               FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID);
+               FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_MAXMB(priv->tx_mb_idx);
        netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
        flexcan_write(reg_mcr, &regs->mcr);
 
@@ -887,18 +889,18 @@ static int flexcan_chip_start(struct net_device *dev)
        flexcan_write(reg_ctrl, &regs->ctrl);
 
        /* clear and invalidate all mailboxes first */
-       for (i = FLEXCAN_TX_BUF_ID; i < ARRAY_SIZE(regs->mb); i++) {
+       for (i = priv->tx_mb_idx; i < ARRAY_SIZE(regs->mb); i++) {
                flexcan_write(FLEXCAN_MB_CODE_RX_INACTIVE,
                              &regs->mb[i].can_ctrl);
        }
 
        /* Errata ERR005829: mark first TX mailbox as INACTIVE */
        flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
-                     &regs->mb[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
+                     &priv->tx_mb_reserved->can_ctrl);
 
        /* mark TX mailbox as INACTIVE */
        flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
-                     &regs->mb[FLEXCAN_TX_BUF_ID].can_ctrl);
+                     &priv->tx_mb->can_ctrl);
 
        /* acceptance mask/acceptance code (accept everything) */
        flexcan_write(0x0, &regs->rxgmask);
@@ -1229,9 +1231,13 @@ static int flexcan_probe(struct platform_device *pdev)
        priv->devtype_data = devtype_data;
        priv->reg_xceiver = reg_xceiver;
 
+       priv->tx_mb_idx = FLEXCAN_TX_MB_OFF_FIFO;
+       priv->tx_mb_reserved = &regs->mb[FLEXCAN_TX_MB_RESERVED_OFF_FIFO];
+       priv->tx_mb = &regs->mb[priv->tx_mb_idx];
+
        priv->reg_imask1_default = FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
                FLEXCAN_IFLAG_RX_FIFO_AVAILABLE |
-               FLEXCAN_IFLAG_BUF(FLEXCAN_TX_BUF_ID);
+               FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
 
        netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);