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2023-10-05can: dev: add can_state_get_by_berr_counter() to return the CAN state based ↵Marc Kleine-Budde
on the current error counters Some CAN controllers do not have a register that contains the current CAN state, but only a register that contains the error counters. Introduce a new function can_state_get_by_berr_counter() that returns the current TX and RX state depending on the provided CAN bit error counters. Link: https://lore.kernel.org/all/20231005-at91_can-rx_offload-v2-1-9987d53600e0@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-07-28can: rx-offload: add can_rx_offload_get_echo_skb_queue_tail()Marc Kleine-Budde
Add can_rx_offload_get_echo_skb_queue_tail(). This function addds the echo skb at the end of rx-offload the queue. This is intended for devices without timestamp support. Link: https://lore.kernel.org/all/20230718-gs_usb-rx-offload-v2-2-716e542d14d5@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-07-28can: rx-offload: rename rx_offload_get_echo_skb() -> ↵Marc Kleine-Budde
can_rx_offload_get_echo_skb_queue_timestamp() Rename the rx_offload_get_echo_skb() function to can_rx_offload_get_echo_skb_queue_timestamp(), since it inserts the echo skb into the rx-offload queue sorted by timestamp. This is a preparation for adding can_rx_offload_get_echo_skb_queue_tail(), which adds the echo skb to the end of the queue. This is intended for devices that do not support timestamps. Link: https://lore.kernel.org/all/20230718-gs_usb-rx-offload-v2-1-716e542d14d5@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-06-22can: length: refactor frame lengths definition to add size in bitsVincent Mailhol
Introduce a method to calculate the exact size in bits of a CAN(-FD) frame with or without dynamic bitstuffing. These are all the possible combinations taken into account: - Classical CAN or CAN-FD - Standard or Extended frame format - CAN-FD CRC17 or CRC21 - Include or not intermission Instead of doing several individual macro definitions, declare the can_frame_bits() function-like macro. To this extent, do a full refactoring of the length definitions. In addition add the can_frame_bytes(). This function-like macro replaces the existing macro: - CAN_FRAME_OVERHEAD_SFF: can_frame_bytes(false, false, 0) - CAN_FRAME_OVERHEAD_EFF: can_frame_bytes(false, true, 0) - CANFD_FRAME_OVERHEAD_SFF: can_frame_bytes(true, false, 0) - CANFD_FRAME_OVERHEAD_EFF: can_frame_bytes(true, true, 0) Function-like macros were chosen over inline functions because they can be used to initialize const struct fields. The different maximum frame lengths (maximum data length, including intermission) are as follow: Frame type bits bytes ------------------------------------------------------- Classic CAN SFF no bitstuffing 111 14 Classic CAN EFF no bitstuffing 131 17 Classic CAN SFF bitstuffing 135 17 Classic CAN EFF bitstuffing 160 20 CAN-FD SFF no bitstuffing 579 73 CAN-FD EFF no bitstuffing 598 75 CAN-FD SFF bitstuffing 712 89 CAN-FD EFF bitstuffing 736 92 The macro CAN_FRAME_LEN_MAX and CANFD_FRAME_LEN_MAX are kept as an alias to, respectively, can_frame_bytes(false, true, CAN_MAX_DLEN) and can_frame_bytes(true, true, CANFD_MAX_DLEN). In addition to the above: - Use ISO 11898-1:2015 definitions for the names of the CAN frame fields. - Include linux/bits.h for use of BITS_PER_BYTE. - Include linux/math.h for use of mult_frac() and DIV_ROUND_UP(). N.B: the use of DIV_ROUND_UP() is not new to this patch, but the include was previously omitted. - Add copyright 2023 for myself. Suggested-by: Thomas Kopp <Thomas.Kopp@microchip.com> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Reviewed-by: Thomas Kopp <Thomas.Kopp@microchip.com> Link: https://lore.kernel.org/all/20230611025728.450837-4-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-06-22can: length: fix description of the RRS fieldVincent Mailhol
The CAN-FD frames only have one reserved bit. The bit corresponding to Classical CAN frame's RTR bit is called the "Remote Request Substitution (RRS)" [1]. N.B. The RRS is not to be confused with the Substitute Remote Request (SRR). Fix the description in the CANFD_FRAME_OVERHEAD_SFF/EFF macros. The total remains unchanged, so this is just a documentation fix. In addition to the above add myself as copyright owner for 2020 (as coauthor of the initial version, c.f. Fixes tag). [1] ISO 11898-1:2015 paragraph 10.4.2.3 "Arbitration field": RSS bit [only in FD Frames] The RRS bit shall be transmitted in FD Frames at the position of the RTR bit in Classical Frames. The RRS bit shall be transmitted dominant, but receivers shall accept recessive and dominant RRS bits. Fixes: 85d99c3e2a13 ("can: length: can_skb_get_frame_len(): introduce function to get data length of frame in data link layer") Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Reviewed-by: Thomas Kopp <Thomas.Kopp@microchip.com> Link: https://lore.kernel.org/all/20230611025728.450837-3-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-06-22can: length: fix bitstuffing countVincent Mailhol
The Stuff Bit Count is always coded on 4 bits [1]. Update the Stuff Bit Count size accordingly. In addition, the CRC fields of CAN FD Frames contain stuff bits at fixed positions called fixed stuff bits [2]. The CRC field starts with a fixed stuff bit and then has another fixed stuff bit after each fourth bit [2], which allows us to derive this formula: FSB count = 1 + round_down(len(CRC field)/4) The length of the CRC field is [1]: len(CRC field) = len(Stuff Bit Count) + len(CRC) = 4 + len(CRC) with len(CRC) either 17 or 21 bits depending of the payload length. In conclusion, for CRC17: FSB count = 1 + round_down((4 + 17)/4) = 6 and for CRC 21: FSB count = 1 + round_down((4 + 21)/4) = 7 Add a Fixed Stuff bits (FSB) field with above values and update CANFD_FRAME_OVERHEAD_SFF and CANFD_FRAME_OVERHEAD_EFF accordingly. [1] ISO 11898-1:2015 section 10.4.2.6 "CRC field": The CRC field shall contain the CRC sequence followed by a recessive CRC delimiter. For FD Frames, the CRC field shall also contain the stuff count. Stuff count If FD Frames, the stuff count shall be at the beginning of the CRC field. It shall consist of the stuff bit count modulo 8 in a 3-bit gray code followed by a parity bit [...] [2] ISO 11898-1:2015 paragraph 10.5 "Frame coding": In the CRC field of FD Frames, the stuff bits shall be inserted at fixed positions; they are called fixed stuff bits. There shall be a fixed stuff bit before the first bit of the stuff count, even if the last bits of the preceding field are a sequence of five consecutive bits of identical value, there shall be only the fixed stuff bit, there shall not be two consecutive stuff bits. A further fixed stuff bit shall be inserted after each fourth bit of the CRC field [...] Fixes: 85d99c3e2a13 ("can: length: can_skb_get_frame_len(): introduce function to get data length of frame in data link layer") Suggested-by: Thomas Kopp <Thomas.Kopp@microchip.com> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Reviewed-by: Thomas Kopp <Thomas.Kopp@microchip.com> Link: https://lore.kernel.org/all/20230611025728.450837-2-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-05-15can: length: make header self containedMarc Kleine-Budde
Include the headers that "can/length.h" depends on. Fixes: bdd2e413192d ("can: dev: move length related code into seperate file") Link: https://lore.kernel.org/all/20230509122854.350426-1-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-02-08can: bittiming: can_calc_bittiming(): add missing parameter to no-op functionMarc Kleine-Budde
In commit 286c0e09e8e0 ("can: bittiming: can_changelink() pass extack down callstack") a new parameter was added to can_calc_bittiming(), however the static inline no-op (which is used if CONFIG_CAN_CALC_BITTIMING is disabled) wasn't converted. Add the new parameter to the static inline no-op of can_calc_bittiming(). Fixes: 286c0e09e8e0 ("can: bittiming: can_changelink() pass extack down callstack") Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/20230207201734.2905618-1-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-02-06can: bittiming: factor out can_sjw_set_default() and can_sjw_check()Marc Kleine-Budde
Factor out the functionality of assigning a SJW default value into can_sjw_set_default() and the checking the SJW limits into can_sjw_check(). This functions will be improved and called from a different function in the following patches. Link: https://lore.kernel.org/all/20230202110854.2318594-11-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-02-06can: bittiming: can_changelink() pass extack down callstackMarc Kleine-Budde
This is a preparation patch. In order to pass warning/error messages during netlink calls back to user space, pass the extack struct down the callstack of can_changelink(), the actual error messages will be added in the following ptaches. Link: https://lore.kernel.org/all/20230202110854.2318594-10-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-11-24can: sja1000: fix size of OCR_MODE_MASK defineHeiko Schocher
bitfield mode in ocr register has only 2 bits not 3, so correct the OCR_MODE_MASK define. Signed-off-by: Heiko Schocher <hs@denx.de> Link: https://lore.kernel.org/all/20221123071636.2407823-1-hs@denx.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-11-07can: dev: fix skb drop checkOliver Hartkopp
In commit a6d190f8c767 ("can: skb: drop tx skb if in listen only mode") the priv->ctrlmode element is read even on virtual CAN interfaces that do not create the struct can_priv at startup. This out-of-bounds read may lead to CAN frame drops for virtual CAN interfaces like vcan and vxcan. This patch mainly reverts the original commit and adds a new helper for CAN interface drivers that provide the required information in struct can_priv. Fixes: a6d190f8c767 ("can: skb: drop tx skb if in listen only mode") Reported-by: Dariusz Stojaczyk <Dariusz.Stojaczyk@opensynergy.com> Cc: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Cc: Max Staudt <max@enpas.org> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/all/20221102095431.36831-1-socketcan@hartkopp.net Cc: stable@vger.kernel.org # 6.0.x [mkl: patch pch_can, too] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15can: dev: add CAN XL support to virtual CANOliver Hartkopp
Make use of new can_skb_get_data_len() helper. Add support for variable CANXL MTU using the new can_is_canxl_dev_mtu(). Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/all/20220912170725.120748-7-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15can: canxl: update CAN infrastructure for CAN XL framesOliver Hartkopp
- add new ETH_P_CANXL ethernet protocol type - update skb checks for CAN XL - add alloc_canxl_skb() which now needs a data length parameter - introduce init_can_skb_reserve() to reduce code duplication Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/all/20220912170725.120748-6-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15can: skb: add skb CAN frame data length helpersOliver Hartkopp
Add two helpers to retrieve the data length from CAN sk_buffs and prepare the length information to be a uint16 value for the CAN XL support. Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/all/20220912170725.120748-3-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15can: skb: unify skb CAN frame identification helpersOliver Hartkopp
Replace open coded checks for sk_buffs containing Classical CAN and CAN FD frame structures as a preparation for CAN XL support. With the added length check the unintended processing of CAN XL frames having the CANXL_XLF bit set can be suppressed even when the skb->len fits to non CAN XL frames. The CAN_RAW socket needs a rework to use these helpers. Therefore the use of these helpers is postponed to the CAN_RAW CAN XL integration. The J1939 protocol gets a check for Classical CAN frames too. Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/all/20220912170725.120748-2-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28can: dev: add generic function can_eth_ioctl_hwts()Vincent Mailhol
Tools based on libpcap (such as tcpdump) expect the SIOCSHWTSTAMP ioctl call to be supported. This is also specified in the kernel doc [1]. The purpose of this ioctl is to toggle the hardware timestamps. Currently, CAN devices which support hardware timestamping have those always activated. can_eth_ioctl_hwts() is a dumb function that will always succeed when requested to set tx_type to HWTSTAMP_TX_ON or rx_filter to HWTSTAMP_FILTER_ALL. [1] Kernel doc: Timestamping, section 3.1 "Hardware Timestamping Implementation: Device Drivers" Link: https://docs.kernel.org/networking/timestamping.html#hardware-timestamping-implementation-device-drivers Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/all/20220727101641.198847-9-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28can: dev: add generic function can_ethtool_op_get_ts_info_hwts()Vincent Mailhol
Add function can_ethtool_op_get_ts_info_hwts(). This function will be used by CAN devices with hardware TX/RX timestamping support to implement ethtool_ops::get_ts_info. This function does not offer support to activate/deactivate hardware timestamps at device level nor support the filter options (which is currently the case for all CAN devices with hardware timestamping support). The fact that hardware timestamp can not be deactivated at hardware level does not impact the userland. As long as the user do not set SO_TIMESTAMPING using a setsockopt() or ioctl(), the kernel will not emit TX timestamps (RX timestamps will still be reproted as it is the case currently). Drivers which need more fine grained control remains free to implement their own function, but we foresee that the generic function introduced here will be sufficient for the majority. Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/all/20220727101641.198847-8-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-03can: netlink: dump bitrate 0 if can_priv::bittiming.bitrate is -1UDario Binacchi
Upcoming changes on slcan driver will require you to specify a bitrate of value -1 to prevent the open_candev() from failing but at the same time highlighting that it is a fake value. In this case the command `ip --details -s -s link show' would print 4294967295 as the bitrate value. The patch change this value in 0. Link: https://lore.kernel.org/all/20220628163137.413025-5-dario.binacchi@amarulasolutions.com Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com> Tested-by: Jeroen Hofstee <jhofstee@victronenergy.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-06-11can: skb: move can_dropped_invalid_skb() and can_skb_headroom_valid() to skb.cVincent Mailhol
The functions can_dropped_invalid_skb() and can_skb_headroom_valid() grew a lot over the years to a point which it does not make much sense to have them defined as static inline in header files. Move those two functions to the .c counterpart of skb.h. can_skb_headroom_valid()'s only caller being can_dropped_invalid_skb(), the declaration is removed from the header. Only can_dropped_invalid_skb() gets its symbol exported. While doing so, do a small cleanup: add brackets around the else block in can_dropped_invalid_skb(). Link: https://lore.kernel.org/all/20220610143009.323579-7-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Max Staudt <max@enpas.org> Tested-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-05-19can: can-dev: remove obsolete CAN LED supportOliver Hartkopp
Since commit 30f3b42147ba6f ("can: mark led trigger as broken") the CAN specific LED support was disabled and marked as BROKEN. As the common LED support with CONFIG_LEDS_TRIGGER_NETDEV should do this work now the code can be removed as preparation for a CAN netdevice Kconfig rework. Link: https://lore.kernel.org/all/20220518154527.29046-1-socketcan@hartkopp.net Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> [mkl: remove led.h from MAINTAINERS] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-04-19can: rx-offload: rename can_rx_offload_queue_sorted() -> ↵Marc Kleine-Budde
can_rx_offload_queue_timestamp() This patch renames the function can_rx_offload_queue_sorted() to can_rx_offload_queue_timestamp(). This better describes what the function does, it adds a newly RX'ed skb to the sorted queue by its timestamp. Link: https://lore.kernel.org/all/20220417194327.2699059-1-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-02-24can: bittiming: mark function arguments and local variables as constMarc Kleine-Budde
This patch marks the arguments of some functions as well as some local variables as constant. Link: https://lore.kernel.org/all/20220124215642.3474154-7-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05can: dev: reorder struct can_priv members for better packingVincent Mailhol
Save eight bytes of holes on x86-64 architectures by reordering the members of struct can_priv. Before: | $ pahole -C can_priv drivers/net/can/dev/dev.o | struct can_priv { | struct net_device * dev; /* 0 8 */ | struct can_device_stats can_stats; /* 8 24 */ | const struct can_bittiming_const * bittiming_const; /* 32 8 */ | const struct can_bittiming_const * data_bittiming_const; /* 40 8 */ | struct can_bittiming bittiming; /* 48 32 */ | /* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */ | struct can_bittiming data_bittiming; /* 80 32 */ | const struct can_tdc_const * tdc_const; /* 112 8 */ | struct can_tdc tdc; /* 120 12 */ | /* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */ | unsigned int bitrate_const_cnt; /* 132 4 */ | const u32 * bitrate_const; /* 136 8 */ | const u32 * data_bitrate_const; /* 144 8 */ | unsigned int data_bitrate_const_cnt; /* 152 4 */ | u32 bitrate_max; /* 156 4 */ | struct can_clock clock; /* 160 4 */ | unsigned int termination_const_cnt; /* 164 4 */ | const u16 * termination_const; /* 168 8 */ | u16 termination; /* 176 2 */ | | /* XXX 6 bytes hole, try to pack */ | | struct gpio_desc * termination_gpio; /* 184 8 */ | /* --- cacheline 3 boundary (192 bytes) --- */ | u16 termination_gpio_ohms[2]; /* 192 4 */ | enum can_state state; /* 196 4 */ | u32 ctrlmode; /* 200 4 */ | u32 ctrlmode_supported; /* 204 4 */ | int restart_ms; /* 208 4 */ | | /* XXX 4 bytes hole, try to pack */ | | struct delayed_work restart_work; /* 216 88 */ | | /* XXX last struct has 4 bytes of padding */ | | /* --- cacheline 4 boundary (256 bytes) was 48 bytes ago --- */ | int (*do_set_bittiming)(struct net_device *); /* 304 8 */ | int (*do_set_data_bittiming)(struct net_device *); /* 312 8 */ | /* --- cacheline 5 boundary (320 bytes) --- */ | int (*do_set_mode)(struct net_device *, enum can_mode); /* 320 8 */ | int (*do_set_termination)(struct net_device *, u16); /* 328 8 */ | int (*do_get_state)(const struct net_device *, enum can_state *); /* 336 8 */ | int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 344 8 */ | unsigned int echo_skb_max; /* 352 4 */ | | /* XXX 4 bytes hole, try to pack */ | | struct sk_buff * * echo_skb; /* 360 8 */ | | /* size: 368, cachelines: 6, members: 32 */ | /* sum members: 354, holes: 3, sum holes: 14 */ | /* paddings: 1, sum paddings: 4 */ | /* last cacheline: 48 bytes */ | }; After: | $ pahole -C can_priv drivers/net/can/dev/dev.o | struct can_priv { | struct net_device * dev; /* 0 8 */ | struct can_device_stats can_stats; /* 8 24 */ | const struct can_bittiming_const * bittiming_const; /* 32 8 */ | const struct can_bittiming_const * data_bittiming_const; /* 40 8 */ | struct can_bittiming bittiming; /* 48 32 */ | /* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */ | struct can_bittiming data_bittiming; /* 80 32 */ | const struct can_tdc_const * tdc_const; /* 112 8 */ | struct can_tdc tdc; /* 120 12 */ | /* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */ | unsigned int bitrate_const_cnt; /* 132 4 */ | const u32 * bitrate_const; /* 136 8 */ | const u32 * data_bitrate_const; /* 144 8 */ | unsigned int data_bitrate_const_cnt; /* 152 4 */ | u32 bitrate_max; /* 156 4 */ | struct can_clock clock; /* 160 4 */ | unsigned int termination_const_cnt; /* 164 4 */ | const u16 * termination_const; /* 168 8 */ | u16 termination; /* 176 2 */ | | /* XXX 6 bytes hole, try to pack */ | | struct gpio_desc * termination_gpio; /* 184 8 */ | /* --- cacheline 3 boundary (192 bytes) --- */ | u16 termination_gpio_ohms[2]; /* 192 4 */ | unsigned int echo_skb_max; /* 196 4 */ | struct sk_buff * * echo_skb; /* 200 8 */ | enum can_state state; /* 208 4 */ | u32 ctrlmode; /* 212 4 */ | u32 ctrlmode_supported; /* 216 4 */ | int restart_ms; /* 220 4 */ | struct delayed_work restart_work; /* 224 88 */ | | /* XXX last struct has 4 bytes of padding */ | | /* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */ | int (*do_set_bittiming)(struct net_device *); /* 312 8 */ | /* --- cacheline 5 boundary (320 bytes) --- */ | int (*do_set_data_bittiming)(struct net_device *); /* 320 8 */ | int (*do_set_mode)(struct net_device *, enum can_mode); /* 328 8 */ | int (*do_set_termination)(struct net_device *, u16); /* 336 8 */ | int (*do_get_state)(const struct net_device *, enum can_state *); /* 344 8 */ | int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 352 8 */ | | /* size: 360, cachelines: 6, members: 32 */ | /* sum members: 354, holes: 1, sum holes: 6 */ | /* paddings: 1, sum paddings: 4 */ | /* last cacheline: 40 bytes */ | }; Link: https://lore.kernel.org/all/20211213160226.56219-4-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05can: dev: add sanity check in can_set_static_ctrlmode()Vincent Mailhol
Previous patch removed can_priv::ctrlmode_static to replace it with can_get_static_ctrlmode(). A condition sine qua non for this to work is that the controller static modes should never be set in can_priv::ctrlmode_supported (c.f. the comment on can_priv::ctrlmode_supported which states that it is for "options that can be *modified* by netlink"). Also, this condition is already correctly fulfilled by all existing drivers which rely on the ctrlmode_static feature. Nonetheless, we added an extra safeguard in can_set_static_ctrlmode() to return an error value and to warn the developer who would be adventurous enough to set to static a given feature that is already set to supported. The drivers which rely on the static controller mode are then updated to check the return value of can_set_static_ctrlmode(). Link: https://lore.kernel.org/all/20211213160226.56219-3-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05can: dev: replace can_priv::ctrlmode_static by can_get_static_ctrlmode()Vincent Mailhol
The statically enabled features of a CAN controller can be retrieved using below formula: | u32 ctrlmode_static = priv->ctrlmode & ~priv->ctrlmode_supported; As such, there is no need to store this information. This patch remove the field ctrlmode_static of struct can_priv and provides, in replacement, the inline function can_get_static_ctrlmode() which returns the same value. Link: https://lore.kernel.org/all/20211213160226.56219-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05can: do not increase tx_bytes statistics for RTR framesVincent Mailhol
The actual payload length of the CAN Remote Transmission Request (RTR) frames is always 0, i.e. no payload is transmitted on the wire. However, those RTR frames still use the DLC to indicate the length of the requested frame. As such, net_device_stats::tx_bytes should not be increased when sending RTR frames. The function can_get_echo_skb() already returns the correct length, even for RTR frames (c.f. [1]). However, for historical reasons, the drivers do not use can_get_echo_skb()'s return value and instead, most of them store a temporary length (or dlc) in some local structure or array. Using the return value of can_get_echo_skb() solves the issue. After doing this, such length/dlc fields become unused and so this patch does the adequate cleaning when needed. This patch fixes all the CAN drivers. Finally, can_get_echo_skb() is decorated with the __must_check attribute in order to force future drivers to correctly use its return value (else the compiler would emit a warning). [1] commit ed3320cec279 ("can: dev: __can_get_echo_skb(): fix real payload length return value for RTR frames") Link: https://lore.kernel.org/all/20211207121531.42941-6-mailhol.vincent@wanadoo.fr Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Chen-Yu Tsai <wens@csie.org> Cc: Jernej Skrabec <jernej.skrabec@gmail.com> Cc: Yasushi SHOJI <yashi@spacecubics.com> Cc: Oliver Hartkopp <socketcan@hartkopp.net> Cc: Stephane Grosjean <s.grosjean@peak-system.com> Cc: Andreas Larsson <andreas@gaisler.com> Tested-by: Jimmy Assarsson <extja@kvaser.com> # kvaser Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Acked-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2 Tested-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2 [mkl: add conversion for grcan] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-12-08can: bittiming: replace CAN units with the generic ones from linux/units.hVincent Mailhol
In [1], we introduced a set of units in linux/can/bittiming.h. Since then, generic SI prefixes were added to linux/units.h in [2]. Those new prefixes can perfectly replace CAN specific ones. This patch replaces all occurrences of the CAN units with their corresponding prefix (from linux/units) and the unit (as a comment) according to below table. CAN units SI metric prefix (from linux/units) + unit (as a comment) ------------------------------------------------------------------------ CAN_KBPS KILO /* BPS */ CAN_MBPS MEGA /* BPS */ CAM_MHZ MEGA /* Hz */ The definition are then removed from linux/can/bittiming.h [1] commit 1d7750760b70 ("can: bittiming: add CAN_KBPS, CAN_MBPS and CAN_MHZ macros") [2] commit 26471d4a6cf8 ("units: Add SI metric prefix definitions") Link: https://lore.kernel.org/all/20211124014536.782550-1-mailhol.vincent@wanadoo.fr Suggested-by: Jimmy Assarsson <extja@kvaser.com> Suggested-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-10-24can: dev: add can_tdc_get_relative_tdco() helper functionVincent Mailhol
struct can_tdc::tdco represents the absolute offset from TDCV. Some controllers use instead an offset relative to the Sample Point (SP) such that: | SSP = TDCV + absolute TDCO | = TDCV + SP + relative TDCO Consequently: | relative TDCO = absolute TDCO - SP The function can_tdc_get_relative_tdco() allow to retrieve this relative TDCO value. Link: https://lore.kernel.org/all/20210918095637.20108-7-mailhol.vincent@wanadoo.fr CC: Stefan Mätje <Stefan.Maetje@esd.eu> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-10-24can: netlink: add can_priv::do_get_auto_tdcv() to retrieve tdcv from deviceVincent Mailhol
Some CAN device can measure the TDCV (Transmission Delay Compensation Value) automatically for each transmitted CAN frames. A callback function do_get_auto_tdcv() is added to retrieve that value. This function is used only if CAN_CTRLMODE_TDC_AUTO is enabled (if CAN_CTRLMODE_TDC_MANUAL is selected, the TDCV value is provided by the user). If the device does not support reporting of TDCV, do_get_auto_tdcv() should be set to NULL and TDCV will not be reported by the netlink interface. On success, do_get_auto_tdcv() shall return 0. If the value can not be measured by the device, for example because network is down or because no frames were transmitted yet, can_priv::do_get_auto_tdcv() shall return a negative error code (e.g. -EINVAL) to signify that the value is not yet available. In such cases, TDCV is not reported by the netlink interface. Link: https://lore.kernel.org/all/20210918095637.20108-6-mailhol.vincent@wanadoo.fr CC: Stefan Mätje <stefan.maetje@esd.eu> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-10-24can: bittiming: change can_calc_tdco()'s prototype to not directly modify privVincent Mailhol
The function can_calc_tdco() directly retrieves can_priv from the net_device and directly modifies it. This is annoying for the upcoming patch. In drivers/net/can/dev/netlink.c:can_changelink(), the data bittiming are written to a temporary structure and memcpyed to can_priv only after everything succeeded. In the next patch, where we will introduce the netlink interface for TDC parameters, we will add a new TDC block which can potentially fail. For this reason, the data bittiming temporary structure has to be copied after that to-be-introduced TDC block. However, TDC also needs to access data bittiming information. We change the prototype so that the data bittiming structure is passed to can_calc_tdco() as an argument instead of retrieving it from priv. This way can_calc_tdco() can access the data bittiming before it gets memcpyed to priv. Link: https://lore.kernel.org/all/20210918095637.20108-4-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-10-24can: bittiming: change unit of TDC parameters to clock periodsVincent Mailhol
In the current implementation, all Transmission Delay Compensation (TDC) parameters are expressed in time quantum. However, ISO 11898-1 actually specifies that these should be expressed in *minimum* time quantum. Furthermore, the minimum time quantum is specified to be "one node clock period long" (c.f. paragraph 11.3.1.1 "Bit time"). For sake of simplicity, we prefer to use the "clock period" term instead of "minimum time quantum" because we believe that it is more broadly understood. This patch fixes that discrepancy by updating the documentation and the formula for TDCO calculation. N.B. In can_calc_tdco(), the sample point (in time quantum) was calculated using a division, thus introducing a risk of rounding and truncation errors. On top of changing the unit to clock period, we also modified the formula to use only additions. Link: https://lore.kernel.org/all/20210918095637.20108-3-mailhol.vincent@wanadoo.fr Suggested-by: Stefan Mätje <Stefan.Maetje@esd.eu> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-10-24can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_minVincent Mailhol
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay compensation" that "the configuration range for [the] SSP position shall be at least 0 to 63 minimum time quanta." Because SSP = TDCV + TDCO, it means that we should allow both TDCV and TDCO to hold zero value in order to honor SSP's minimum possible value. However, current implementation assigned special meaning to TDCV and TDCO's zero values: * TDCV = 0 -> TDCV is automatically measured by the transceiver. * TDCO = 0 -> TDC is off. In order to allow for those values to really be zero and to maintain current features, we introduce two new flags: * CAN_CTRLMODE_TDC_AUTO indicates that the controller support automatic measurement of TDCV. * CAN_CTRLMODE_TDC_MANUAL indicates that the controller support manual configuration of TDCV. N.B.: current implementation failed to provide an option for the driver to indicate that only manual mode was supported. TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function can_tdc_is_enabled() which is also introduced in this patch. Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to struct can_tdc_const. While we are not convinced that those three fields could be anything else than zero, we can imagine that some controllers might specify a lower bound on these. Thus, those minimums are really added "just in case". Comments of struct can_tdc and can_tdc_const are updated accordingly. Finally, the changes are applied to the etas_es58x driver. Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-08-19can: dev: provide optional GPIO based termination supportOleksij Rempel
For CAN buses to work, a termination resistor has to be present at both ends of the bus. This resistor is usually 120 Ohms, other values may be required for special bus topologies. This patch adds support for a generic GPIO based CAN termination. The resistor value has to be specified via device tree, and it can only be attached to or detached from the bus. By default the termination is not active. Link: https://lore.kernel.org/r/20210818071232.20585-4-o.rempel@pengutronix.de Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-07-25can: flexcan: add platform data headerAngelo Dureghello
Add platform data header for flexcan. Link: https://lore.kernel.org/r/20210702094841.327679-1-angelo@kernel-space.org Signed-off-by: Angelo Dureghello <angelo@kernel-space.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-07-25can: bittiming: fix documentation for struct can_tdcMarc Kleine-Budde
This patch fixes a typo in the documentation for struct can_tdc::tdcv. The number "0" refers to automatic mode not the letter "O". Further two grammar errors in the documentation for struct can_tdc are fixed. First grammar error: add a missing third person 's'. Second grammar error: replace "such as" by "such that". The intent is to give a condition, not an example. Fixes: 289ea9e4ae59 ("can: add new CAN FD bittiming parameters: Transmitter Delay Compensation (TDC)") Link: https://lore.kernel.org/r/20210616095922.2430415-1-mkl@pengutronix.de Link: https://lore.kernel.org/r/20210616124057.60723-1-mailhol.vincent@wanadoo.fr Co-developed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-07-25can: rx-offload: can_rx_offload_threaded_irq_finish(): add new function to ↵Marc Kleine-Budde
be called from threaded interrupt After reading all CAN frames from the controller in the IRQ handler and storing them into a skb_queue, the driver calls napi_schedule(). In the napi poll function the skb from the skb_queue are then pushed into the networking stack. However if napi_schedule() is called from a threaded IRQ handler this triggers the following error: | NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! To avoid this, create a new rx-offload function (can_rx_offload_threaded_irq_finish()) with a call to local_bh_disable()/local_bh_enable() around the napi_schedule() call. Convert all drivers that call can_rx_offload_irq_finish() from threaded IRQ context to can_rx_offload_threaded_irq_finish(). Link: https://lore.kernel.org/r/20210724204745.736053-4-mkl@pengutronix.de Suggested-by: Daniel Glöckner <dg@emlix.com> Tested-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-07-25can: rx-offload: can_rx_offload_irq_finish(): directly call napi_schedule()Marc Kleine-Budde
Instead of calling can_rx_offload_schedule() call napi_schedule() directly. As this was the last use of can_rx_offload_schedule() remove this helper function. Link: https://lore.kernel.org/r/20210724204745.736053-3-mkl@pengutronix.de Tested-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-07-25can: rx-offload: add skb queue for use during ISRMarc Kleine-Budde
Adding a skb to the skb_queue in rx-offload requires to take a lock. This commit avoids this by adding an unlocked skb queue that is appended at the end of the ISR. Having one lock at the end of the ISR should be OK as the HW is empty, not about to overflow. Link: https://lore.kernel.org/r/20210724204745.736053-2-mkl@pengutronix.de Tested-by: Oleksij Rempel <o.rempel@pengutronix.de> Co-developed-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: bittiming: add CAN_KBPS, CAN_MBPS and CAN_MHZ macrosVincent Mailhol
Add three macro to simplify the readability of big bit timing numbers: - CAN_KBPS: kilobits per second (one thousand) - CAN_MBPS: megabits per second (one million) - CAN_MHZ: megahertz per second (one million) Example: u32 bitrate_max = 8 * CAN_MBPS; struct can_clock clock = {.freq = 80 * CAN_MHZ}; instead of: u32 bitrate_max = 8000000; struct can_clock clock = {.freq = 80000000}; Apply the new macro to driver/net/can/dev/bittiming.c. Link: https://lore.kernel.org/r/20210306054040.76483-1-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: bittiming: add calculation for CAN FD Transmitter Delay Compensation (TDC)Vincent Mailhol
The logic for the tdco calculation is to just reuse the normal sample point: tdco = sp. Because the sample point is expressed in tenth of percent and the tdco is expressed in time quanta, a conversion is needed. At the end, ssp = tdcv + tdco = tdcv + sp. Another popular method is to set tdco to the middle of the bit: tdc->tdco = can_bit_time(dbt) / 2 During benchmark tests, we could not find a clear advantages for one of the two methods. The tdco calculation is triggered each time the data_bittiming is changed so that users relying on automated calculation can use the netlink interface the exact same way without need of new parameters. For example, a command such as: ip link set canX type can bitrate 500000 dbitrate 4000000 fd on would trigger the calculation. The user using CONFIG_CAN_CALC_BITTIMING who does not want automated calculation needs to manually set tdco to zero. For example with: ip link set canX type can tdco 0 bitrate 500000 dbitrate 4000000 fd on (if the tdco parameter is provided in a previous command, it will be overwritten). If tdcv is set to zero (default), it is automatically calculated by the transiver for each frame. As such, there is no code in the kernel to calculate it. tdcf has no automated calculation functions because we could not figure out a formula for this parameter. Link: https://lore.kernel.org/r/20210224002008.4158-6-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: dev: reorder struct can_priv members for better packingVincent Mailhol
Save eight bytes of holes on x86-64 architectures by reordering struct can_priv members. Before: $ pahole -C can_priv drivers/net/can/dev/dev.o struct can_priv { struct net_device * dev; /* 0 8 */ struct can_device_stats can_stats; /* 8 24 */ struct can_bittiming bittiming; /* 32 32 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct can_bittiming data_bittiming; /* 64 32 */ const struct can_bittiming_const * bittiming_const; /* 96 8 */ const struct can_bittiming_const * data_bittiming_const; /* 104 8 */ struct can_tdc tdc; /* 112 12 */ /* XXX 4 bytes hole, try to pack */ /* --- cacheline 2 boundary (128 bytes) --- */ const struct can_tdc_const * tdc_const; /* 128 8 */ const u16 * termination_const; /* 136 8 */ unsigned int termination_const_cnt; /* 144 4 */ u16 termination; /* 148 2 */ /* XXX 2 bytes hole, try to pack */ const u32 * bitrate_const; /* 152 8 */ unsigned int bitrate_const_cnt; /* 160 4 */ /* XXX 4 bytes hole, try to pack */ const u32 * data_bitrate_const; /* 168 8 */ unsigned int data_bitrate_const_cnt; /* 176 4 */ u32 bitrate_max; /* 180 4 */ struct can_clock clock; /* 184 4 */ enum can_state state; /* 188 4 */ /* --- cacheline 3 boundary (192 bytes) --- */ u32 ctrlmode; /* 192 4 */ u32 ctrlmode_supported; /* 196 4 */ u32 ctrlmode_static; /* 200 4 */ int restart_ms; /* 204 4 */ struct delayed_work restart_work; /* 208 168 */ /* XXX last struct has 4 bytes of padding */ /* --- cacheline 5 boundary (320 bytes) was 56 bytes ago --- */ int (*do_set_bittiming)(struct net_device *); /* 376 8 */ /* --- cacheline 6 boundary (384 bytes) --- */ int (*do_set_data_bittiming)(struct net_device *); /* 384 8 */ int (*do_set_mode)(struct net_device *, enum can_mode); /* 392 8 */ int (*do_set_termination)(struct net_device *, u16); /* 400 8 */ int (*do_get_state)(const struct net_device *, enum can_state *); /* 408 8 */ int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 416 8 */ unsigned int echo_skb_max; /* 424 4 */ /* XXX 4 bytes hole, try to pack */ struct sk_buff * * echo_skb; /* 432 8 */ /* size: 440, cachelines: 7, members: 31 */ /* sum members: 426, holes: 4, sum holes: 14 */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 56 bytes */ }; After: $ pahole -C can_priv drivers/net/can/dev/dev.o struct can_priv { struct net_device * dev; /* 0 8 */ struct can_device_stats can_stats; /* 8 24 */ const struct can_bittiming_const * bittiming_const; /* 32 8 */ const struct can_bittiming_const * data_bittiming_const; /* 40 8 */ struct can_bittiming bittiming; /* 48 32 */ /* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */ struct can_bittiming data_bittiming; /* 80 32 */ const struct can_tdc_const * tdc_const; /* 112 8 */ struct can_tdc tdc; /* 120 12 */ /* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */ unsigned int bitrate_const_cnt; /* 132 4 */ const u32 * bitrate_const; /* 136 8 */ const u32 * data_bitrate_const; /* 144 8 */ unsigned int data_bitrate_const_cnt; /* 152 4 */ u32 bitrate_max; /* 156 4 */ struct can_clock clock; /* 160 4 */ unsigned int termination_const_cnt; /* 164 4 */ const u16 * termination_const; /* 168 8 */ u16 termination; /* 176 2 */ /* XXX 2 bytes hole, try to pack */ enum can_state state; /* 180 4 */ u32 ctrlmode; /* 184 4 */ u32 ctrlmode_supported; /* 188 4 */ /* --- cacheline 3 boundary (192 bytes) --- */ u32 ctrlmode_static; /* 192 4 */ int restart_ms; /* 196 4 */ struct delayed_work restart_work; /* 200 168 */ /* XXX last struct has 4 bytes of padding */ /* --- cacheline 5 boundary (320 bytes) was 48 bytes ago --- */ int (*do_set_bittiming)(struct net_device *); /* 368 8 */ int (*do_set_data_bittiming)(struct net_device *); /* 376 8 */ /* --- cacheline 6 boundary (384 bytes) --- */ int (*do_set_mode)(struct net_device *, enum can_mode); /* 384 8 */ int (*do_set_termination)(struct net_device *, u16); /* 392 8 */ int (*do_get_state)(const struct net_device *, enum can_state *); /* 400 8 */ int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 408 8 */ unsigned int echo_skb_max; /* 416 4 */ /* XXX 4 bytes hole, try to pack */ struct sk_buff * * echo_skb; /* 424 8 */ /* size: 432, cachelines: 7, members: 31 */ /* sum members: 426, holes: 2, sum holes: 6 */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 48 bytes */ }; Link: https://lore.kernel.org/r/20210224002008.4158-3-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: add new CAN FD bittiming parameters: Transmitter Delay Compensation (TDC)Vincent Mailhol
At high bit rates, the propagation delay from the TX pin to the RX pin of the transceiver causes measurement errors: the sample point on the RX pin might occur on the previous bit. This issue is addressed in ISO 11898-1 section 11.3.3 "Transmitter delay compensation" (TDC). This patch adds two new structures: can_tdc and can_tdc_const in order to implement this TDC. The structures are then added to can_priv. A controller supports TDC if an only if can_priv::tdc_const is not NULL. TDC is active if and only if: - fd flag is on - can_priv::tdc.tdco is not zero. It is the driver responsibility to check those two conditions are met. No new controller modes are introduced (i.e. no CAN_CTRL_MODE_TDC) in order not to be redundant with above logic. The names of the parameters are chosen to match existing CAN controllers specification. References: - Bosch C_CAN FD8: https://www.bosch-semiconductors.com/media/ip_modules/pdf_2/c_can_fd8/users_manual_c_can_fd8_r210_1.pdf - Microchip CAN FD Controller Module: http://ww1.microchip.com/downloads/en/DeviceDoc/MCP251XXFD-CAN-FD-Controller-Module-Family-Reference-Manual-20005678B.pdf - SAM E701/S70/V70/V71 Family: https://www.mouser.com/datasheet/2/268/60001527A-1284321.pdf Link: https://lore.kernel.org/r/20210224002008.4158-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: dev: can_free_echo_skb(): extend to return can frame lengthMarc Kleine-Budde
In order to implement byte queue limits (bql) in CAN drivers, the length of the CAN frame needs to be passed into the networking stack even if the transmission failed for some reason. To avoid to calculate this length twice, extend can_free_echo_skb() to return that value. Convert all users of this function, too. This patch is the natural extension of commit: | 9420e1d495e2 ("can: dev: can_get_echo_skb(): extend to return can | frame length") Link: https://lore.kernel.org/r/20210319142700.305648-3-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-01can: skb: can_skb_set_owner(): fix ref counting if socket was closed before ↵Oleksij Rempel
setting skb ownership There are two ref count variables controlling the free()ing of a socket: - struct sock::sk_refcnt - which is changed by sock_hold()/sock_put() - struct sock::sk_wmem_alloc - which accounts the memory allocated by the skbs in the send path. In case there are still TX skbs on the fly and the socket() is closed, the struct sock::sk_refcnt reaches 0. In the TX-path the CAN stack clones an "echo" skb, calls sock_hold() on the original socket and references it. This produces the following back trace: | WARNING: CPU: 0 PID: 280 at lib/refcount.c:25 refcount_warn_saturate+0x114/0x134 | refcount_t: addition on 0; use-after-free. | Modules linked in: coda_vpu(E) v4l2_jpeg(E) videobuf2_vmalloc(E) imx_vdoa(E) | CPU: 0 PID: 280 Comm: test_can.sh Tainted: G E 5.11.0-04577-gf8ff6603c617 #203 | Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) | Backtrace: | [<80bafea4>] (dump_backtrace) from [<80bb0280>] (show_stack+0x20/0x24) r7:00000000 r6:600f0113 r5:00000000 r4:81441220 | [<80bb0260>] (show_stack) from [<80bb593c>] (dump_stack+0xa0/0xc8) | [<80bb589c>] (dump_stack) from [<8012b268>] (__warn+0xd4/0x114) r9:00000019 r8:80f4a8c2 r7:83e4150c r6:00000000 r5:00000009 r4:80528f90 | [<8012b194>] (__warn) from [<80bb09c4>] (warn_slowpath_fmt+0x88/0xc8) r9:83f26400 r8:80f4a8d1 r7:00000009 r6:80528f90 r5:00000019 r4:80f4a8c2 | [<80bb0940>] (warn_slowpath_fmt) from [<80528f90>] (refcount_warn_saturate+0x114/0x134) r8:00000000 r7:00000000 r6:82b44000 r5:834e5600 r4:83f4d540 | [<80528e7c>] (refcount_warn_saturate) from [<8079a4c8>] (__refcount_add.constprop.0+0x4c/0x50) | [<8079a47c>] (__refcount_add.constprop.0) from [<8079a57c>] (can_put_echo_skb+0xb0/0x13c) | [<8079a4cc>] (can_put_echo_skb) from [<8079ba98>] (flexcan_start_xmit+0x1c4/0x230) r9:00000010 r8:83f48610 r7:0fdc0000 r6:0c080000 r5:82b44000 r4:834e5600 | [<8079b8d4>] (flexcan_start_xmit) from [<80969078>] (netdev_start_xmit+0x44/0x70) r9:814c0ba0 r8:80c8790c r7:00000000 r6:834e5600 r5:82b44000 r4:82ab1f00 | [<80969034>] (netdev_start_xmit) from [<809725a4>] (dev_hard_start_xmit+0x19c/0x318) r9:814c0ba0 r8:00000000 r7:82ab1f00 r6:82b44000 r5:00000000 r4:834e5600 | [<80972408>] (dev_hard_start_xmit) from [<809c6584>] (sch_direct_xmit+0xcc/0x264) r10:834e5600 r9:00000000 r8:00000000 r7:82b44000 r6:82ab1f00 r5:834e5600 r4:83f27400 | [<809c64b8>] (sch_direct_xmit) from [<809c6c0c>] (__qdisc_run+0x4f0/0x534) To fix this problem, only set skb ownership to sockets which have still a ref count > 0. Fixes: 0ae89beb283a ("can: add destructor for self generated skbs") Cc: Oliver Hartkopp <socketcan@hartkopp.net> Cc: Andre Naujoks <nautsch2@gmail.com> Link: https://lore.kernel.org/r/20210226092456.27126-1-o.rempel@pengutronix.de Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-02-24net: introduce CAN specific pointer in the struct net_deviceOleksij Rempel
Since 20dd3850bcf8 ("can: Speed up CAN frame receiption by using ml_priv") the CAN framework uses per device specific data in the AF_CAN protocol. For this purpose the struct net_device->ml_priv is used. Later the ml_priv usage in CAN was extended for other users, one of them being CAN_J1939. Later in the kernel ml_priv was converted to an union, used by other drivers. E.g. the tun driver started storing it's stats pointer. Since tun devices can claim to be a CAN device, CAN specific protocols will wrongly interpret this pointer, which will cause system crashes. Mostly this issue is visible in the CAN_J1939 stack. To fix this issue, we request a dedicated CAN pointer within the net_device struct. Reported-by: syzbot+5138c4dd15a0401bec7b@syzkaller.appspotmail.com Fixes: 20dd3850bcf8 ("can: Speed up CAN frame receiption by using ml_priv") Fixes: ffd956eef69b ("can: introduce CAN midlayer private and allocate it automatically") Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Fixes: 497a5757ce4e ("tun: switch to net core provided statistics counters") Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://lore.kernel.org/r/20210223070127.4538-1-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-27can: dev: export can_get_state_str() functionVincent Mailhol
The can_get_state_str() function is also relevant to the drivers. Export the symbol and make it visible in the can/dev.h header. Link: https://lore.kernel.org/r/20210119170355.12040-1-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14can: dev: can_rx_offload_get_echo_skb(): extend to return can frame lengthMarc Kleine-Budde
In order to implement byte queue limits (bql) in CAN drivers, the length of the CAN frame needs to be passed into the networking stack after queueing and after transmission completion. To avoid to calculate this length twice, extend can_rx_offload_get_echo_skb() to return that value. Convert all users of this function, too. Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20210111141930.693847-15-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14can: dev: can_get_echo_skb(): extend to return can frame lengthMarc Kleine-Budde
In order to implement byte queue limits (bql) in CAN drivers, the length of the CAN frame needs to be passed into the networking stack after queueing and after transmission completion. To avoid to calculate this length twice, extend can_get_echo_skb() to return that value. Convert all users of this function, too. Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14can: dev: can_put_echo_skb(): extend to handle frame_lenVincent Mailhol
Add a frame_len argument to can_put_echo_skb() which is used to save length of the CAN frame into field frame_len of struct can_skb_priv so that it can be later used after transmission completion. Convert all users of this function, too. Drivers which implement BQL call can_put_echo_skb() with the output of can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an input (in the same way that NULL would be given to can_get_echo_skb()). This way, we have a nice symmetry between the two echo functions. Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>