openwrt/target/linux/layerscape/patches-5.4/802-can-0006-can-rx-offload...

207 lines
5.8 KiB
Diff

From 42abc4a8a97a87734c759c02c5ba255ed5124a2c Mon Sep 17 00:00:00 2001
From: Joakim Zhang <qiangqing.zhang@nxp.com>
Date: Fri, 12 Jul 2019 08:02:38 +0000
Subject: [PATCH] can: rx-offload: Prepare for CAN FD support
The skbs for classic CAN and CAN FD frames are allocated with separate
functions: alloc_can_skb() and alloc_canfd_skb().
In order to support CAN FD frames via the rx-offload helper, the driver
itself has to allocate the skb (depending whether it received a classic
CAN or CAN FD frame), as the rx-offload helper cannot know which kind of
CAN frame the driver has received.
This patch moves the allocation of the skb into the struct
can_rx_offload::mailbox_read callbacks of the the flexcan and ti_hecc
driver and adjusts the rx-offload helper accordingly.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
drivers/net/can/flexcan.c | 27 +++++++++++-----
drivers/net/can/rx-offload.c | 70 ++++++++++--------------------------------
include/linux/can/rx-offload.h | 6 ++--
3 files changed, 40 insertions(+), 63 deletions(-)
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -785,16 +785,23 @@ static inline struct flexcan_priv *rx_of
return container_of(offload, struct flexcan_priv, offload);
}
-static unsigned int flexcan_mailbox_read(struct can_rx_offload *offload,
- struct can_frame *cf,
- u32 *timestamp, unsigned int n)
+static struct sk_buff *flexcan_mailbox_read(struct can_rx_offload *offload,
+ unsigned int n, u32 *timestamp,
+ bool drop)
{
struct flexcan_priv *priv = rx_offload_to_priv(offload);
struct flexcan_regs __iomem *regs = priv->regs;
struct flexcan_mb __iomem *mb;
+ struct sk_buff *skb;
+ struct can_frame *cf;
u32 reg_ctrl, reg_id, reg_iflag1;
int i;
+ if (unlikely(drop)) {
+ skb = ERR_PTR(-ENOBUFS);
+ goto mark_as_read;
+ }
+
mb = flexcan_get_mb(priv, n);
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
@@ -808,7 +815,7 @@ static unsigned int flexcan_mailbox_read
code = reg_ctrl & FLEXCAN_MB_CODE_MASK;
if ((code != FLEXCAN_MB_CODE_RX_FULL) &&
(code != FLEXCAN_MB_CODE_RX_OVERRUN))
- return 0;
+ return NULL;
if (code == FLEXCAN_MB_CODE_RX_OVERRUN) {
/* This MB was overrun, we lost data */
@@ -818,11 +825,17 @@ static unsigned int flexcan_mailbox_read
} else {
reg_iflag1 = priv->read(&regs->iflag1);
if (!(reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE))
- return 0;
+ return NULL;
reg_ctrl = priv->read(&mb->can_ctrl);
}
+ skb = alloc_can_skb(offload->dev, &cf);
+ if (!skb) {
+ skb = ERR_PTR(-ENOMEM);
+ goto mark_as_read;
+ }
+
/* increase timstamp to full 32 bit */
*timestamp = reg_ctrl << 16;
@@ -841,7 +854,7 @@ static unsigned int flexcan_mailbox_read
*(__be32 *)(cf->data + i) = data;
}
- /* mark as read */
+ mark_as_read:
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
/* Clear IRQ */
if (n < 32)
@@ -858,7 +871,7 @@ static unsigned int flexcan_mailbox_read
*/
priv->read(&regs->timer);
- return 1;
+ return skb;
}
--- a/drivers/net/can/rx-offload.c
+++ b/drivers/net/can/rx-offload.c
@@ -139,71 +139,35 @@ static int can_rx_offload_compare(struct
static struct sk_buff *
can_rx_offload_offload_one(struct can_rx_offload *offload, unsigned int n)
{
- struct sk_buff *skb = NULL, *skb_error = NULL;
+ struct sk_buff *skb;
struct can_rx_offload_cb *cb;
- struct can_frame *cf;
- int ret;
+ bool drop = false;
+ u32 timestamp;
- if (likely(skb_queue_len(&offload->skb_queue) <
- offload->skb_queue_len_max)) {
- skb = alloc_can_skb(offload->dev, &cf);
- if (unlikely(!skb))
- skb_error = ERR_PTR(-ENOMEM); /* skb alloc failed */
- } else {
- skb_error = ERR_PTR(-ENOBUFS); /* skb_queue is full */
- }
-
- /* If queue is full or skb not available, drop by reading into
- * overflow buffer.
- */
- if (unlikely(skb_error)) {
- struct can_frame cf_overflow;
- u32 timestamp;
-
- ret = offload->mailbox_read(offload, &cf_overflow,
- &timestamp, n);
-
- /* Mailbox was empty. */
- if (unlikely(!ret))
- return NULL;
-
- /* Mailbox has been read and we're dropping it or
- * there was a problem reading the mailbox.
- *
- * Increment error counters in any case.
- */
- offload->dev->stats.rx_dropped++;
- offload->dev->stats.rx_fifo_errors++;
-
- /* There was a problem reading the mailbox, propagate
- * error value.
- */
- if (unlikely(ret < 0))
- return ERR_PTR(ret);
-
- return skb_error;
- }
-
- cb = can_rx_offload_get_cb(skb);
- ret = offload->mailbox_read(offload, cf, &cb->timestamp, n);
+ /* If queue is full drop frame */
+ if (unlikely(skb_queue_len(&offload->skb_queue) >
+ offload->skb_queue_len_max))
+ drop = true;
+ skb = offload->mailbox_read(offload, n, &timestamp, drop);
/* Mailbox was empty. */
- if (unlikely(!ret)) {
- kfree_skb(skb);
+ if (unlikely(!skb))
return NULL;
- }
-
- /* There was a problem reading the mailbox, propagate error value. */
- if (unlikely(ret < 0)) {
- kfree_skb(skb);
+ /* There was a problem reading the mailbox, propagate
+ * error value.
+ */
+ if (unlikely(IS_ERR(skb))) {
offload->dev->stats.rx_dropped++;
offload->dev->stats.rx_fifo_errors++;
- return ERR_PTR(ret);
+ return skb;
}
/* Mailbox was read. */
+ cb = can_rx_offload_get_cb(skb);
+ cb->timestamp = timestamp;
+
return skb;
}
--- a/include/linux/can/rx-offload.h
+++ b/include/linux/can/rx-offload.h
@@ -15,9 +15,9 @@
struct can_rx_offload {
struct net_device *dev;
- unsigned int (*mailbox_read)(struct can_rx_offload *offload,
- struct can_frame *cf,
- u32 *timestamp, unsigned int mb);
+ struct sk_buff *(*mailbox_read)(struct can_rx_offload *offload,
+ unsigned int mb, u32 *timestamp,
+ bool drop);
struct sk_buff_head skb_queue;
u32 skb_queue_len_max;