From 7c9416365c60f150ef8961a2855fafbc7394ad6b Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:04:33 +0200 Subject: canfd: add new data structures and constants - add new struct canfd_frame - check identical element offsets in struct can_frame and struct canfd_frame - new ETH_P_CANFD definition to tag CAN FD skbs correctly - add CAN_MTU and CANFD_MTU definitions for easy frame and mode detection - add CAN[FD]_MAX_[DLC|DLEN] helper constants to remove hard coded values - update existing struct can_frame with helper constants and comments Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can.h | 59 ++++++++++++++++++++++++++++++++++++++++++++---- include/linux/if_ether.h | 3 ++- 2 files changed, 56 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/can.h b/include/linux/can.h index 17334c09bd93..1a66cf6112ae 100644 --- a/include/linux/can.h +++ b/include/linux/can.h @@ -46,18 +46,67 @@ typedef __u32 canid_t; */ typedef __u32 can_err_mask_t; +/* CAN payload length and DLC definitions according to ISO 11898-1 */ +#define CAN_MAX_DLC 8 +#define CAN_MAX_DLEN 8 + +/* CAN FD payload length and DLC definitions according to ISO 11898-7 */ +#define CANFD_MAX_DLC 15 +#define CANFD_MAX_DLEN 64 + /** * struct can_frame - basic CAN frame structure - * @can_id: the CAN ID of the frame and CAN_*_FLAG flags, see above. - * @can_dlc: the data length field of the CAN frame - * @data: the CAN frame payload. + * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition + * @can_dlc: frame payload length in byte (0 .. 8) aka data length code + * N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1 + * mapping of the 'data length code' to the real payload length + * @data: CAN frame payload (up to 8 byte) */ struct can_frame { canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ - __u8 can_dlc; /* data length code: 0 .. 8 */ - __u8 data[8] __attribute__((aligned(8))); + __u8 can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */ + __u8 data[CAN_MAX_DLEN] __attribute__((aligned(8))); }; +/* + * defined bits for canfd_frame.flags + * + * As the default for CAN FD should be to support the high data rate in the + * payload section of the frame (HDR) and to support up to 64 byte in the + * data section (EDL) the bits are only set in the non-default case. + * Btw. as long as there's no real implementation for CAN FD network driver + * these bits are only preliminary. + * + * RX: NOHDR/NOEDL - info about received CAN FD frame + * ESI - bit from originating CAN controller + * TX: NOHDR/NOEDL - control per-frame settings if supported by CAN controller + * ESI - bit is set by local CAN controller + */ +#define CANFD_NOHDR 0x01 /* frame without high data rate */ +#define CANFD_NOEDL 0x02 /* frame without extended data length */ +#define CANFD_ESI 0x04 /* error state indicator */ + +/** + * struct canfd_frame - CAN flexible data rate frame structure + * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition + * @len: frame payload length in byte (0 .. CANFD_MAX_DLEN) + * @flags: additional flags for CAN FD + * @__res0: reserved / padding + * @__res1: reserved / padding + * @data: CAN FD frame payload (up to CANFD_MAX_DLEN byte) + */ +struct canfd_frame { + canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ + __u8 len; /* frame payload length in byte */ + __u8 flags; /* additional flags for CAN FD */ + __u8 __res0; /* reserved / padding */ + __u8 __res1; /* reserved / padding */ + __u8 data[CANFD_MAX_DLEN] __attribute__((aligned(8))); +}; + +#define CAN_MTU (sizeof(struct can_frame)) +#define CANFD_MTU (sizeof(struct canfd_frame)) + /* particular protocols of the protocol family PF_CAN */ #define CAN_RAW 1 /* RAW sockets */ #define CAN_BCM 2 /* Broadcast Manager */ diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h index 56d907a2c804..167ce5b363d2 100644 --- a/include/linux/if_ether.h +++ b/include/linux/if_ether.h @@ -105,7 +105,8 @@ #define ETH_P_WAN_PPP 0x0007 /* Dummy type for WAN PPP frames*/ #define ETH_P_PPP_MP 0x0008 /* Dummy type for PPP MP frames */ #define ETH_P_LOCALTALK 0x0009 /* Localtalk pseudo type */ -#define ETH_P_CAN 0x000C /* Controller Area Network */ +#define ETH_P_CAN 0x000C /* CAN: Controller Area Network */ +#define ETH_P_CANFD 0x000D /* CANFD: CAN flexible data rate*/ #define ETH_P_PPPTALK 0x0010 /* Dummy type for Atalk over PPP*/ #define ETH_P_TR_802_2 0x0011 /* 802.2 frames */ #define ETH_P_MOBITEX 0x0015 /* Mobitex (kaz@cafe.net) */ -- cgit v1.2.3 From 8b01939f358d680cea971151375268cfdb6b9635 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:33:02 +0200 Subject: canfd: add support for CAN FD in PF_CAN core - handle ETH_P_CAN and ETH_P_CANFD skbuffs - update sanity checks for CAN and CAN FD - make sure the CAN frame can pass the selected CAN netdevice on send - bump core version and abi version to indicate the new CAN FD support Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can/core.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/can/core.h b/include/linux/can/core.h index 0ccc1cd28b95..78c6c52073ad 100644 --- a/include/linux/can/core.h +++ b/include/linux/can/core.h @@ -17,10 +17,10 @@ #include #include -#define CAN_VERSION "20090105" +#define CAN_VERSION "20120528" /* increment this number each time you change some user-space interface */ -#define CAN_ABI_VERSION "8" +#define CAN_ABI_VERSION "9" #define CAN_VERSION_STRING "rev " CAN_VERSION " abi " CAN_ABI_VERSION -- cgit v1.2.3 From e2d265d3b587f5f6f8febc0222aace93302ff0be Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:41:31 +0200 Subject: canfd: add support for CAN FD in CAN_RAW sockets - introduce a new sockopt CAN_RAW_FD_FRAMES to allow CAN FD frames - handle CAN frames and CAN FD frames simultaneously when enabled Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can/raw.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/can/raw.h b/include/linux/can/raw.h index 781f3a3701be..a814062b0719 100644 --- a/include/linux/can/raw.h +++ b/include/linux/can/raw.h @@ -23,7 +23,8 @@ enum { CAN_RAW_FILTER = 1, /* set 0 .. n can_filter(s) */ CAN_RAW_ERR_FILTER, /* set filter for error frames */ CAN_RAW_LOOPBACK, /* local loopback (default:on) */ - CAN_RAW_RECV_OWN_MSGS /* receive my own msgs (default:off) */ + CAN_RAW_RECV_OWN_MSGS, /* receive my own msgs (default:off) */ + CAN_RAW_FD_FRAMES, /* allow CAN FD frames (default:off) */ }; #endif -- cgit v1.2.3 From 1e0625facab2e871472472b7df87d8fbe6caf75a Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:48:21 +0200 Subject: candev: add/update helpers for CAN FD - update sanity checks - add DLC to length conversion helpers - can_dlc2len() - get data length from can_dlc with sanitized can_dlc - can_len2dlc() - map the sanitized data length to an appropriate DLC Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can/dev.h | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) (limited to 'include/linux') diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 5d2efe7e3f1b..ee5a771fb20d 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -61,23 +61,40 @@ struct can_priv { * To be used in the CAN netdriver receive path to ensure conformance with * ISO 11898-1 Chapter 8.4.2.3 (DLC field) */ -#define get_can_dlc(i) (min_t(__u8, (i), 8)) +#define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) +#define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ static inline int can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) { - const struct can_frame *cf = (struct can_frame *)skb->data; - - if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) { - kfree_skb(skb); - dev->stats.tx_dropped++; - return 1; - } + const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + + if (skb->protocol == htons(ETH_P_CAN)) { + if (unlikely(skb->len != CAN_MTU || + cfd->len > CAN_MAX_DLEN)) + goto inval_skb; + } else if (skb->protocol == htons(ETH_P_CANFD)) { + if (unlikely(skb->len != CANFD_MTU || + cfd->len > CANFD_MAX_DLEN)) + goto inval_skb; + } else + goto inval_skb; return 0; + +inval_skb: + kfree_skb(skb); + dev->stats.tx_dropped++; + return 1; } +/* get data length from can_dlc with sanitized can_dlc */ +u8 can_dlc2len(u8 can_dlc); + +/* map the sanitized data length to an appropriate data length code */ +u8 can_len2dlc(u8 len); + struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); void free_candev(struct net_device *dev); -- cgit v1.2.3