> -----Original Message-----
> From: linux-can-owner@xxxxxxxxxxxxxxx <linux-can-owner@xxxxxxxxxxxxxxx>
> On Behalf Of Pankaj Bansal
> Sent: 2019年5月28日 17:55
> To: Wolfgang Grandegger <wg@xxxxxxxxxxxxxx>; Marc Kleine-Budde
> <mkl@xxxxxxxxxxxxxx>
> Cc: linux-can@xxxxxxxxxxxxxxx
> Subject: [PATCH v2 1/4] net: can: flexcan: use CAN FD frames for Tx/Rx
>
> Use can FD frames for Tx/Rx operations. This would be needed in upcoming
> SOC LX2160A, which supports CAN FD protocol
>
> Signed-off-by: Pankaj Bansal <pankaj.bansal@xxxxxxx>
> ---
>
> Notes:
> V2:
> - No change
>
> drivers/net/can/flexcan.c | 36 +++++++++++++++++++-------------
> drivers/net/can/rx-offload.c | 32 +++++++++++++++++++++-------
> include/linux/can/rx-offload.h | 6 +++++-
> 3 files changed, 50 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index
> 44258cc871b3..931efffb8fa2 100644
> --- a/drivers/net/can/flexcan.c
> +++ b/drivers/net/can/flexcan.c
> @@ -609,10 +609,10 @@ static int flexcan_get_berr_counter(const struct
> net_device *dev, static netdev_tx_t flexcan_start_xmit(struct sk_buff *skb,
> struct net_device *dev) {
> const struct flexcan_priv *priv = netdev_priv(dev);
> - struct can_frame *cf = (struct can_frame *)skb->data;
> + struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
> u32 can_id;
> u32 data;
> - u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | (cf->can_dlc << 16);
> + u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | (can_len2dlc(cfd->len) << 16);
> int i;
>
> if (can_dropped_invalid_skb(dev, skb)) @@ -620,18 +620,18 @@ static
> netdev_tx_t flexcan_start_xmit(struct sk_buff *skb, struct net_device *de
>
> netif_stop_queue(dev);
>
> - if (cf->can_id & CAN_EFF_FLAG) {
> - can_id = cf->can_id & CAN_EFF_MASK;
> + if (cfd->can_id & CAN_EFF_FLAG) {
> + can_id = cfd->can_id & CAN_EFF_MASK;
> ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
> } else {
> - can_id = (cf->can_id & CAN_SFF_MASK) << 18;
> + can_id = (cfd->can_id & CAN_SFF_MASK) << 18;
> }
>
> - if (cf->can_id & CAN_RTR_FLAG)
> + if (!can_is_canfd_skb(skb) && (cfd->can_id & CAN_RTR_FLAG))
> ctrl |= FLEXCAN_MB_CNT_RTR;
>
> - for (i = 0; i < cf->can_dlc; i += sizeof(u32)) {
> - data = be32_to_cpup((__be32 *)&cf->data[i]);
> + for (i = 0; i < can_len2dlc(cfd->len); i += sizeof(u32)) {
> + data = be32_to_cpup((__be32 *)&cfd->data[i]);
> priv->write(data, &priv->tx_mb->data[i / sizeof(u32)]);
> }
>
> @@ -760,12 +760,13 @@ static inline struct flexcan_priv
> *rx_offload_to_priv(struct can_rx_offload *off }
>
> static unsigned int flexcan_mailbox_read(struct can_rx_offload *offload,
> - struct can_frame *cf,
> + struct sk_buff *skb,
> u32 *timestamp, unsigned int n)
> {
> struct flexcan_priv *priv = rx_offload_to_priv(offload);
> struct flexcan_regs __iomem *regs = priv->regs;
> struct flexcan_mb __iomem *mb;
> + struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
> u32 reg_ctrl, reg_id, reg_iflag1;
> int i;
>
> @@ -802,17 +803,21 @@ static unsigned int flexcan_mailbox_read(struct
> can_rx_offload *offload,
>
> reg_id = priv->read(&mb->can_id);
> if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
> - cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
> + cfd->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
> else
> - cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;
> + cfd->can_id = (reg_id >> 18) & CAN_SFF_MASK;
>
> if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
> - cf->can_id |= CAN_RTR_FLAG;
> - cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);
> + cfd->can_id |= CAN_RTR_FLAG;
>
> - for (i = 0; i < cf->can_dlc; i += sizeof(u32)) {
> + if (can_is_canfd_skb(skb))
> + cfd->len = can_dlc2len(get_canfd_dlc((reg_ctrl >> 16) & 0xf));
> + else
> + cfd->len = get_can_dlc((reg_ctrl >> 16) & 0xf);
> +
> + for (i = 0; i < cfd->len; i += sizeof(u32)) {
> __be32 data = cpu_to_be32(priv->read(&mb->data[i / sizeof(u32)]));
> - *(__be32 *)(cf->data + i) = data;
> + *(__be32 *)(cfd->data + i) = data;
> }
>
> /* mark as read */
> @@ -1262,6 +1267,7 @@ static int flexcan_open(struct net_device *dev)
> priv->reg_imask1_default = 0;
> priv->reg_imask2_default = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
>
> + priv->offload.fd_enable = false;
> priv->offload.mailbox_read = flexcan_mailbox_read;
>
> if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)
> { diff --git a/drivers/net/can/rx-offload.c b/drivers/net/can/rx-offload.c index
> 2ce4fa8698c7..556b280aa46c 100644
> --- a/drivers/net/can/rx-offload.c
> +++ b/drivers/net/can/rx-offload.c
> @@ -55,11 +55,11 @@ static int can_rx_offload_napi_poll(struct napi_struct
> *napi, int quota)
>
> while ((work_done < quota) &&
> (skb = skb_dequeue(&offload->skb_queue))) {
> - struct can_frame *cf = (struct can_frame *)skb->data;
> + struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
>
> work_done++;
> stats->rx_packets++;
> - stats->rx_bytes += cf->can_dlc;
> + stats->rx_bytes += cfd->len;
> netif_receive_skb(skb);
> }
>
> @@ -122,19 +122,23 @@ static struct sk_buff
> *can_rx_offload_offload_one(struct can_rx_offload *offload {
> struct sk_buff *skb = NULL;
> struct can_rx_offload_cb *cb;
> - struct can_frame *cf;
> + struct canfd_frame *cfd;
> int ret;
>
> /* If queue is full or skb not available, read to discard mailbox */
> if (likely(skb_queue_len(&offload->skb_queue) <=
> - offload->skb_queue_len_max))
> - skb = alloc_can_skb(offload->dev, &cf);
> + offload->skb_queue_len_max)) {
> + if (offload->fd_enable)
> + skb = alloc_canfd_skb(offload->dev, &cfd);
> + else
> + skb = alloc_can_skb(offload->dev,
> + (struct can_frame **)&cfd);
[Joakinm Zhang]
Using alloc_canfd_skb() to allocate skb when FD mode enable, it is unreasonable.
When FD mode enabled, we also can transmit/receive classic frame, should use alloc_can_skb()
in this case. If you still use alloc_can_skb() in this case, it will cause failure for remote frame.
So it is more reasonable to allocate skb after we received the CAN frame.
> + }
>
> if (!skb) {
> - struct can_frame cf_overflow;
> u32 timestamp;
>
> - ret = offload->mailbox_read(offload, &cf_overflow,
> + ret = offload->mailbox_read(offload, offload->skb_overflow,
> ×tamp, n);
> if (ret)
> offload->dev->stats.rx_dropped++;
> @@ -143,7 +147,7 @@ static struct sk_buff
> *can_rx_offload_offload_one(struct can_rx_offload *offload
> }
>
> cb = can_rx_offload_get_cb(skb);
> - ret = offload->mailbox_read(offload, cf, &cb->timestamp, n);
> + ret = offload->mailbox_read(offload, skb, &cb->timestamp, n);
> if (!ret) {
> kfree_skb(skb);
> return NULL;
> @@ -273,6 +277,8 @@ EXPORT_SYMBOL_GPL(can_rx_offload_queue_tail);
>
> static int can_rx_offload_init_queue(struct net_device *dev, struct
> can_rx_offload *offload, unsigned int weight) {
> + struct canfd_frame *cfd;
> +
> offload->dev = dev;
>
> /* Limit queue len to 4x the weight (rounted to next power of two) */
> @@ -286,6 +292,15 @@ static int can_rx_offload_init_queue(struct
> net_device *dev, struct can_rx_offlo
> dev_dbg(dev->dev.parent, "%s: skb_queue_len_max=%d\n",
> __func__, offload->skb_queue_len_max);
>
> + if (offload->fd_enable)
> + offload->skb_overflow = alloc_canfd_skb(offload->dev, &cfd);
> + else
> + offload->skb_overflow = alloc_can_skb(offload->dev,
> + (struct can_frame **)&cfd);
> +
> + if (unlikely(!offload->skb_overflow))
> + return -ENOMEM;
> +
> return 0;
> }
>
> @@ -329,6 +344,7 @@ void can_rx_offload_del(struct can_rx_offload
> *offload) {
> netif_napi_del(&offload->napi);
> skb_queue_purge(&offload->skb_queue);
> + kfree_skb(offload->skb_overflow);
> }
> EXPORT_SYMBOL_GPL(can_rx_offload_del);
>
> diff --git a/include/linux/can/rx-offload.h b/include/linux/can/rx-offload.h
> index 8268811a697e..d01eb356692c 100644
> --- a/include/linux/can/rx-offload.h
> +++ b/include/linux/can/rx-offload.h
> @@ -23,10 +23,13 @@
> struct can_rx_offload {
> struct net_device *dev;
>
> - unsigned int (*mailbox_read)(struct can_rx_offload *offload, struct
> can_frame *cf,
> + unsigned int (*mailbox_read)(struct can_rx_offload *offload,
> + struct sk_buff *skb,
> u32 *timestamp, unsigned int mb);
>
> struct sk_buff_head skb_queue;
> + struct sk_buff *skb_overflow;
> +
> u32 skb_queue_len_max;
>
> unsigned int mb_first;
> @@ -34,6 +37,7 @@ struct can_rx_offload {
>
> struct napi_struct napi;
>
> + bool fd_enable;
> bool inc;
> };
>
> --
> 2.17.1
