can: c_can: Store dlc private

We can avoid the HW access in TX cleanup path for retrieving the DLC
of the sent package if we store the DLC in a private array.

Ideally this should be handled in the can_echo_skb functions, but I
leave that exercise to the CAN folks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Thomas Gleixner 2014-03-18 17:19:14 +00:00 committed by Marc Kleine-Budde
parent c0a9f4d396
commit 9024700854
2 changed files with 29 additions and 27 deletions

View file

@ -145,33 +145,6 @@
#define IF_RX 0
#define IF_TX 1
/*
* IFx register masks:
* allow easy operation on 16-bit registers when the
* argument is 32-bit instead
*/
#define IFX_WRITE_LOW_16BIT(x) ((x) & 0xFFFF)
#define IFX_WRITE_HIGH_16BIT(x) (((x) & 0xFFFF0000) >> 16)
/* message object split */
#define C_CAN_NO_OF_OBJECTS 32
#define C_CAN_MSG_OBJ_RX_NUM 16
#define C_CAN_MSG_OBJ_TX_NUM 16
#define C_CAN_MSG_OBJ_RX_FIRST 1
#define C_CAN_MSG_OBJ_RX_LAST (C_CAN_MSG_OBJ_RX_FIRST + \
C_CAN_MSG_OBJ_RX_NUM - 1)
#define C_CAN_MSG_OBJ_TX_FIRST (C_CAN_MSG_OBJ_RX_LAST + 1)
#define C_CAN_MSG_OBJ_TX_LAST (C_CAN_MSG_OBJ_TX_FIRST + \
C_CAN_MSG_OBJ_TX_NUM - 1)
#define C_CAN_MSG_OBJ_RX_SPLIT 9
#define C_CAN_MSG_RX_LOW_LAST (C_CAN_MSG_OBJ_RX_SPLIT - 1)
#define C_CAN_NEXT_MSG_OBJ_MASK (C_CAN_MSG_OBJ_TX_NUM - 1)
#define RECEIVE_OBJECT_BITS 0x0000ffff
/* status interrupt */
#define STATUS_INTERRUPT 0x8000
@ -537,6 +510,7 @@ static netdev_tx_t c_can_start_xmit(struct sk_buff *skb,
/* prepare message object for transmission */
c_can_write_msg_object(dev, IF_TX, frame, msg_obj_no);
priv->dlc[msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST] = frame->can_dlc;
can_put_echo_skb(skb, dev, msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST);
/*

View file

@ -22,6 +22,33 @@
#ifndef C_CAN_H
#define C_CAN_H
/*
* IFx register masks:
* allow easy operation on 16-bit registers when the
* argument is 32-bit instead
*/
#define IFX_WRITE_LOW_16BIT(x) ((x) & 0xFFFF)
#define IFX_WRITE_HIGH_16BIT(x) (((x) & 0xFFFF0000) >> 16)
/* message object split */
#define C_CAN_NO_OF_OBJECTS 32
#define C_CAN_MSG_OBJ_RX_NUM 16
#define C_CAN_MSG_OBJ_TX_NUM 16
#define C_CAN_MSG_OBJ_RX_FIRST 1
#define C_CAN_MSG_OBJ_RX_LAST (C_CAN_MSG_OBJ_RX_FIRST + \
C_CAN_MSG_OBJ_RX_NUM - 1)
#define C_CAN_MSG_OBJ_TX_FIRST (C_CAN_MSG_OBJ_RX_LAST + 1)
#define C_CAN_MSG_OBJ_TX_LAST (C_CAN_MSG_OBJ_TX_FIRST + \
C_CAN_MSG_OBJ_TX_NUM - 1)
#define C_CAN_MSG_OBJ_RX_SPLIT 9
#define C_CAN_MSG_RX_LOW_LAST (C_CAN_MSG_OBJ_RX_SPLIT - 1)
#define C_CAN_NEXT_MSG_OBJ_MASK (C_CAN_MSG_OBJ_TX_NUM - 1)
#define RECEIVE_OBJECT_BITS 0x0000ffff
enum reg {
C_CAN_CTRL_REG = 0,
C_CAN_CTRL_EX_REG,
@ -173,6 +200,7 @@ struct c_can_priv {
u32 __iomem *raminit_ctrlreg;
unsigned int instance;
void (*raminit) (const struct c_can_priv *priv, bool enable);
u32 dlc[C_CAN_MSG_OBJ_TX_NUM];
};
struct net_device *alloc_c_can_dev(void);