From df6ad5dd838e0fa543ca28ca6154901fa65a9443 Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:03 +0900 Subject: [PATCH 1/7] can: Kconfig: rename config symbol CAN_DEV into CAN_NETLINK In the next patches, the scope of the can-dev module will grow to engloble the software/virtual drivers (slcan, v(x)can). To this extent, release CAN_DEV by renaming it into CAN_NETLINK. The config symbol CAN_DEV will be reused to cover this extended scope. The rationale for the name CAN_NETLINK is that netlink is the predominant feature added here. The current description only mentions platform drivers despite the fact that this symbol is also required by "normal" devices (e.g. USB or PCI) which do not fall under the platform devices category. The description is updated accordingly to fix this gap. Link: https://lore.kernel.org/all/20220610143009.323579-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/Kconfig | 18 +++++++++++------- drivers/net/can/dev/Makefile | 2 +- 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig index b2dcc1e5a388..99f189ad35ad 100644 --- a/drivers/net/can/Kconfig +++ b/drivers/net/can/Kconfig @@ -48,15 +48,19 @@ config CAN_SLCAN can be changed by the 'maxdev=xx' module option. This driver can also be built as a module. If so, the module will be called slcan. -config CAN_DEV - tristate "Platform CAN drivers with Netlink support" +config CAN_NETLINK + tristate "CAN device drivers with Netlink support" default y help - Enables the common framework for platform CAN drivers with Netlink - support. This is the standard library for CAN drivers. - If unsure, say Y. + Enables the common framework for CAN device drivers. This is the + standard library and provides features for the Netlink interface such + as bittiming validation, support of CAN error states, device restart + and others. -if CAN_DEV + This is required by all platform and hardware CAN drivers. If you + plan to use such devices or if unsure, say Y. + +if CAN_NETLINK config CAN_CALC_BITTIMING bool "CAN bit-timing calculation" @@ -164,7 +168,7 @@ source "drivers/net/can/softing/Kconfig" source "drivers/net/can/spi/Kconfig" source "drivers/net/can/usb/Kconfig" -endif +endif #CAN_NETLINK config CAN_DEBUG_DEVICES bool "CAN devices debugging messages" diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile index af2901db473c..5b4c813c6222 100644 --- a/drivers/net/can/dev/Makefile +++ b/drivers/net/can/dev/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_CAN_DEV) += can-dev.o +obj-$(CONFIG_CAN_NETLINK) += can-dev.o can-dev-y += bittiming.o can-dev-y += dev.o can-dev-y += length.o From 6a5286442fb64a2d512e4059004441e59c786ebc Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:04 +0900 Subject: [PATCH 2/7] can: Kconfig: turn menu "CAN Device Drivers" into a menuconfig using CAN_DEV In the next patches, the software/virtual drivers (slcan, v(x)can) will depend on drivers/net/can/dev/skb.o. This patch changes the scope of the can-dev module to include the above mentioned drivers. To do so, we reuse the menu "CAN Device Drivers" and turn it into a configmenu using the config symbol CAN_DEV (which we released in previous patch). Also, add a description to this new CAN_DEV menuconfig. The symbol CAN_DEV now only triggers the build of skb.o. For this reasons, all the macros from linux/module.h are deported from drivers/net/can/dev/dev.c to drivers/net/can/dev/skb.c. Finally, drivers/net/can/dev/Makefile is adjusted accordingly. Link: https://lore.kernel.org/all/20220610143009.323579-3-mailhol.vincent@wanadoo.fr Suggested-by: Oliver Hartkopp Signed-off-by: Vincent Mailhol Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/Kconfig | 29 ++++++++++++++++++++++++++--- drivers/net/can/dev/Makefile | 16 +++++++++------- drivers/net/can/dev/dev.c | 9 +-------- drivers/net/can/dev/skb.c | 7 +++++++ 4 files changed, 43 insertions(+), 18 deletions(-) diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig index 99f189ad35ad..3c692af16676 100644 --- a/drivers/net/can/Kconfig +++ b/drivers/net/can/Kconfig @@ -1,5 +1,25 @@ # SPDX-License-Identifier: GPL-2.0-only -menu "CAN Device Drivers" + +menuconfig CAN_DEV + tristate "CAN Device Drivers" + default y + help + Controller Area Network (CAN) is serial communications protocol up to + 1Mbit/s for its original release (now known as Classical CAN) and up + to 8Mbit/s for the more recent CAN with Flexible Data-Rate + (CAN-FD). The CAN bus was originally mainly for automotive, but is now + widely used in marine (NMEA2000), industrial, and medical + applications. More information on the CAN network protocol family + PF_CAN is contained in . + + This section contains all the CAN(-FD) device drivers including the + virtual ones. If you own such devices or plan to use the virtual CAN + interfaces to develop applications, say Y here. + + To compile as a module, choose M here: the module will be called + can-dev. + +if CAN_DEV config CAN_VCAN tristate "Virtual Local CAN Interface (vcan)" @@ -49,7 +69,7 @@ config CAN_SLCAN also be built as a module. If so, the module will be called slcan. config CAN_NETLINK - tristate "CAN device drivers with Netlink support" + bool "CAN device drivers with Netlink support" default y help Enables the common framework for CAN device drivers. This is the @@ -57,6 +77,9 @@ config CAN_NETLINK as bittiming validation, support of CAN error states, device restart and others. + The additional features selected by this option will be added to the + can-dev module. + This is required by all platform and hardware CAN drivers. If you plan to use such devices or if unsure, say Y. @@ -178,4 +201,4 @@ config CAN_DEBUG_DEVICES a problem with CAN support and want to see more of what is going on. -endmenu +endif #CAN_DEV diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile index 5b4c813c6222..1baaf7020f7c 100644 --- a/drivers/net/can/dev/Makefile +++ b/drivers/net/can/dev/Makefile @@ -1,9 +1,11 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_CAN_NETLINK) += can-dev.o -can-dev-y += bittiming.o -can-dev-y += dev.o -can-dev-y += length.o -can-dev-y += netlink.o -can-dev-y += rx-offload.o -can-dev-y += skb.o +obj-$(CONFIG_CAN_DEV) += can-dev.o + +can-dev-y += skb.o + +can-dev-$(CONFIG_CAN_NETLINK) += bittiming.o +can-dev-$(CONFIG_CAN_NETLINK) += dev.o +can-dev-$(CONFIG_CAN_NETLINK) += length.o +can-dev-$(CONFIG_CAN_NETLINK) += netlink.o +can-dev-$(CONFIG_CAN_NETLINK) += rx-offload.o diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c index 96c9d9db00cf..523eaacfe29e 100644 --- a/drivers/net/can/dev/dev.c +++ b/drivers/net/can/dev/dev.c @@ -4,7 +4,6 @@ * Copyright (C) 2008-2009 Wolfgang Grandegger */ -#include #include #include #include @@ -17,12 +16,6 @@ #include #include -#define MOD_DESC "CAN device driver interface" - -MODULE_DESCRIPTION(MOD_DESC); -MODULE_LICENSE("GPL v2"); -MODULE_AUTHOR("Wolfgang Grandegger "); - static void can_update_state_error_stats(struct net_device *dev, enum can_state new_state) { @@ -513,7 +506,7 @@ static __init int can_dev_init(void) err = can_netlink_register(); if (!err) - pr_info(MOD_DESC "\n"); + pr_info("CAN device driver interface\n"); return err; } diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index 61660248c69e..a4208f125b76 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -5,6 +5,13 @@ */ #include +#include + +#define MOD_DESC "CAN device driver interface" + +MODULE_DESCRIPTION(MOD_DESC); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Wolfgang Grandegger "); /* Local echo of CAN messages * From 0c7e115138830af77d480ee9185bbdc23c6e73a4 Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:05 +0900 Subject: [PATCH 3/7] can: bittiming: move bittiming calculation functions to calc_bittiming.c The canonical way to select or deselect an object during compilation is to use this pattern in the relevant Makefile: bar-$(CONFIG_FOO) := foo.o bittiming.c instead uses some #ifdef CONFIG_CAN_CALC_BITTIMG. Create a new file named calc_bittiming.c with all the functions which are conditionally compiled with CONFIG_CAN_CALC_BITTIMG and modify the Makefile according to above pattern. Link: https://lore.kernel.org/all/20220610143009.323579-4-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/Kconfig | 4 + drivers/net/can/dev/Makefile | 1 + drivers/net/can/dev/bittiming.c | 197 -------------------------- drivers/net/can/dev/calc_bittiming.c | 202 +++++++++++++++++++++++++++ 4 files changed, 207 insertions(+), 197 deletions(-) create mode 100644 drivers/net/can/dev/calc_bittiming.c diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig index 3c692af16676..87470feae6b1 100644 --- a/drivers/net/can/Kconfig +++ b/drivers/net/can/Kconfig @@ -96,6 +96,10 @@ config CAN_CALC_BITTIMING source clock frequencies. Disabling saves some space, but then the bit-timing parameters must be specified directly using the Netlink arguments "tq", "prop_seg", "phase_seg1", "phase_seg2" and "sjw". + + The additional features selected by this option will be added to the + can-dev module. + If unsure, say Y. config CAN_AT91 diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile index 1baaf7020f7c..791e6b297ea3 100644 --- a/drivers/net/can/dev/Makefile +++ b/drivers/net/can/dev/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_CAN_DEV) += can-dev.o can-dev-y += skb.o +can-dev-$(CONFIG_CAN_CALC_BITTIMING) += calc_bittiming.o can-dev-$(CONFIG_CAN_NETLINK) += bittiming.o can-dev-$(CONFIG_CAN_NETLINK) += dev.o can-dev-$(CONFIG_CAN_NETLINK) += length.o diff --git a/drivers/net/can/dev/bittiming.c b/drivers/net/can/dev/bittiming.c index c1e76f0a5064..7ae80763c960 100644 --- a/drivers/net/can/dev/bittiming.c +++ b/drivers/net/can/dev/bittiming.c @@ -4,205 +4,8 @@ * Copyright (C) 2008-2009 Wolfgang Grandegger */ -#include #include -#ifdef CONFIG_CAN_CALC_BITTIMING -#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ - -/* Bit-timing calculation derived from: - * - * Code based on LinCAN sources and H8S2638 project - * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz - * Copyright 2005 Stanislav Marek - * email: pisa@cmp.felk.cvut.cz - * - * Calculates proper bit-timing parameters for a specified bit-rate - * and sample-point, which can then be used to set the bit-timing - * registers of the CAN controller. You can find more information - * in the header file linux/can/netlink.h. - */ -static int -can_update_sample_point(const struct can_bittiming_const *btc, - const unsigned int sample_point_nominal, const unsigned int tseg, - unsigned int *tseg1_ptr, unsigned int *tseg2_ptr, - unsigned int *sample_point_error_ptr) -{ - unsigned int sample_point_error, best_sample_point_error = UINT_MAX; - unsigned int sample_point, best_sample_point = 0; - unsigned int tseg1, tseg2; - int i; - - for (i = 0; i <= 1; i++) { - tseg2 = tseg + CAN_SYNC_SEG - - (sample_point_nominal * (tseg + CAN_SYNC_SEG)) / - 1000 - i; - tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max); - tseg1 = tseg - tseg2; - if (tseg1 > btc->tseg1_max) { - tseg1 = btc->tseg1_max; - tseg2 = tseg - tseg1; - } - - sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) / - (tseg + CAN_SYNC_SEG); - sample_point_error = abs(sample_point_nominal - sample_point); - - if (sample_point <= sample_point_nominal && - sample_point_error < best_sample_point_error) { - best_sample_point = sample_point; - best_sample_point_error = sample_point_error; - *tseg1_ptr = tseg1; - *tseg2_ptr = tseg2; - } - } - - if (sample_point_error_ptr) - *sample_point_error_ptr = best_sample_point_error; - - return best_sample_point; -} - -int can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt, - const struct can_bittiming_const *btc) -{ - struct can_priv *priv = netdev_priv(dev); - unsigned int bitrate; /* current bitrate */ - unsigned int bitrate_error; /* difference between current and nominal value */ - unsigned int best_bitrate_error = UINT_MAX; - unsigned int sample_point_error; /* difference between current and nominal value */ - unsigned int best_sample_point_error = UINT_MAX; - unsigned int sample_point_nominal; /* nominal sample point */ - unsigned int best_tseg = 0; /* current best value for tseg */ - unsigned int best_brp = 0; /* current best value for brp */ - unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0; - u64 v64; - - /* Use CiA recommended sample points */ - if (bt->sample_point) { - sample_point_nominal = bt->sample_point; - } else { - if (bt->bitrate > 800 * KILO /* BPS */) - sample_point_nominal = 750; - else if (bt->bitrate > 500 * KILO /* BPS */) - sample_point_nominal = 800; - else - sample_point_nominal = 875; - } - - /* tseg even = round down, odd = round up */ - for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; - tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { - tsegall = CAN_SYNC_SEG + tseg / 2; - - /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ - brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; - - /* choose brp step which is possible in system */ - brp = (brp / btc->brp_inc) * btc->brp_inc; - if (brp < btc->brp_min || brp > btc->brp_max) - continue; - - bitrate = priv->clock.freq / (brp * tsegall); - bitrate_error = abs(bt->bitrate - bitrate); - - /* tseg brp biterror */ - if (bitrate_error > best_bitrate_error) - continue; - - /* reset sample point error if we have a better bitrate */ - if (bitrate_error < best_bitrate_error) - best_sample_point_error = UINT_MAX; - - can_update_sample_point(btc, sample_point_nominal, tseg / 2, - &tseg1, &tseg2, &sample_point_error); - if (sample_point_error >= best_sample_point_error) - continue; - - best_sample_point_error = sample_point_error; - best_bitrate_error = bitrate_error; - best_tseg = tseg / 2; - best_brp = brp; - - if (bitrate_error == 0 && sample_point_error == 0) - break; - } - - if (best_bitrate_error) { - /* Error in one-tenth of a percent */ - v64 = (u64)best_bitrate_error * 1000; - do_div(v64, bt->bitrate); - bitrate_error = (u32)v64; - if (bitrate_error > CAN_CALC_MAX_ERROR) { - netdev_err(dev, - "bitrate error %d.%d%% too high\n", - bitrate_error / 10, bitrate_error % 10); - return -EDOM; - } - netdev_warn(dev, "bitrate error %d.%d%%\n", - bitrate_error / 10, bitrate_error % 10); - } - - /* real sample point */ - bt->sample_point = can_update_sample_point(btc, sample_point_nominal, - best_tseg, &tseg1, &tseg2, - NULL); - - v64 = (u64)best_brp * 1000 * 1000 * 1000; - do_div(v64, priv->clock.freq); - bt->tq = (u32)v64; - bt->prop_seg = tseg1 / 2; - bt->phase_seg1 = tseg1 - bt->prop_seg; - bt->phase_seg2 = tseg2; - - /* check for sjw user settings */ - if (!bt->sjw || !btc->sjw_max) { - bt->sjw = 1; - } else { - /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */ - if (bt->sjw > btc->sjw_max) - bt->sjw = btc->sjw_max; - /* bt->sjw must not be higher than tseg2 */ - if (tseg2 < bt->sjw) - bt->sjw = tseg2; - } - - bt->brp = best_brp; - - /* real bitrate */ - bt->bitrate = priv->clock.freq / - (bt->brp * (CAN_SYNC_SEG + tseg1 + tseg2)); - - return 0; -} - -void can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const, - const struct can_bittiming *dbt, - u32 *ctrlmode, u32 ctrlmode_supported) - -{ - if (!tdc_const || !(ctrlmode_supported & CAN_CTRLMODE_TDC_AUTO)) - return; - - *ctrlmode &= ~CAN_CTRLMODE_TDC_MASK; - - /* As specified in ISO 11898-1 section 11.3.3 "Transmitter - * delay compensation" (TDC) is only applicable if data BRP is - * one or two. - */ - if (dbt->brp == 1 || dbt->brp == 2) { - /* Sample point in clock periods */ - u32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg + - dbt->phase_seg1) * dbt->brp; - - if (sample_point_in_tc < tdc_const->tdco_min) - return; - tdc->tdco = min(sample_point_in_tc, tdc_const->tdco_max); - *ctrlmode |= CAN_CTRLMODE_TDC_AUTO; - } -} -#endif /* CONFIG_CAN_CALC_BITTIMING */ - /* Checks the validity of the specified bit-timing parameters prop_seg, * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate * prescaler value brp. You can find more information in the header diff --git a/drivers/net/can/dev/calc_bittiming.c b/drivers/net/can/dev/calc_bittiming.c new file mode 100644 index 000000000000..d3caa040614d --- /dev/null +++ b/drivers/net/can/dev/calc_bittiming.c @@ -0,0 +1,202 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix + * Copyright (C) 2006 Andrey Volkov, Varma Electronics + * Copyright (C) 2008-2009 Wolfgang Grandegger + */ + +#include +#include + +#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ + +/* Bit-timing calculation derived from: + * + * Code based on LinCAN sources and H8S2638 project + * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz + * Copyright 2005 Stanislav Marek + * email: pisa@cmp.felk.cvut.cz + * + * Calculates proper bit-timing parameters for a specified bit-rate + * and sample-point, which can then be used to set the bit-timing + * registers of the CAN controller. You can find more information + * in the header file linux/can/netlink.h. + */ +static int +can_update_sample_point(const struct can_bittiming_const *btc, + const unsigned int sample_point_nominal, const unsigned int tseg, + unsigned int *tseg1_ptr, unsigned int *tseg2_ptr, + unsigned int *sample_point_error_ptr) +{ + unsigned int sample_point_error, best_sample_point_error = UINT_MAX; + unsigned int sample_point, best_sample_point = 0; + unsigned int tseg1, tseg2; + int i; + + for (i = 0; i <= 1; i++) { + tseg2 = tseg + CAN_SYNC_SEG - + (sample_point_nominal * (tseg + CAN_SYNC_SEG)) / + 1000 - i; + tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max); + tseg1 = tseg - tseg2; + if (tseg1 > btc->tseg1_max) { + tseg1 = btc->tseg1_max; + tseg2 = tseg - tseg1; + } + + sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) / + (tseg + CAN_SYNC_SEG); + sample_point_error = abs(sample_point_nominal - sample_point); + + if (sample_point <= sample_point_nominal && + sample_point_error < best_sample_point_error) { + best_sample_point = sample_point; + best_sample_point_error = sample_point_error; + *tseg1_ptr = tseg1; + *tseg2_ptr = tseg2; + } + } + + if (sample_point_error_ptr) + *sample_point_error_ptr = best_sample_point_error; + + return best_sample_point; +} + +int can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt, + const struct can_bittiming_const *btc) +{ + struct can_priv *priv = netdev_priv(dev); + unsigned int bitrate; /* current bitrate */ + unsigned int bitrate_error; /* difference between current and nominal value */ + unsigned int best_bitrate_error = UINT_MAX; + unsigned int sample_point_error; /* difference between current and nominal value */ + unsigned int best_sample_point_error = UINT_MAX; + unsigned int sample_point_nominal; /* nominal sample point */ + unsigned int best_tseg = 0; /* current best value for tseg */ + unsigned int best_brp = 0; /* current best value for brp */ + unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0; + u64 v64; + + /* Use CiA recommended sample points */ + if (bt->sample_point) { + sample_point_nominal = bt->sample_point; + } else { + if (bt->bitrate > 800 * KILO /* BPS */) + sample_point_nominal = 750; + else if (bt->bitrate > 500 * KILO /* BPS */) + sample_point_nominal = 800; + else + sample_point_nominal = 875; + } + + /* tseg even = round down, odd = round up */ + for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; + tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { + tsegall = CAN_SYNC_SEG + tseg / 2; + + /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ + brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; + + /* choose brp step which is possible in system */ + brp = (brp / btc->brp_inc) * btc->brp_inc; + if (brp < btc->brp_min || brp > btc->brp_max) + continue; + + bitrate = priv->clock.freq / (brp * tsegall); + bitrate_error = abs(bt->bitrate - bitrate); + + /* tseg brp biterror */ + if (bitrate_error > best_bitrate_error) + continue; + + /* reset sample point error if we have a better bitrate */ + if (bitrate_error < best_bitrate_error) + best_sample_point_error = UINT_MAX; + + can_update_sample_point(btc, sample_point_nominal, tseg / 2, + &tseg1, &tseg2, &sample_point_error); + if (sample_point_error >= best_sample_point_error) + continue; + + best_sample_point_error = sample_point_error; + best_bitrate_error = bitrate_error; + best_tseg = tseg / 2; + best_brp = brp; + + if (bitrate_error == 0 && sample_point_error == 0) + break; + } + + if (best_bitrate_error) { + /* Error in one-tenth of a percent */ + v64 = (u64)best_bitrate_error * 1000; + do_div(v64, bt->bitrate); + bitrate_error = (u32)v64; + if (bitrate_error > CAN_CALC_MAX_ERROR) { + netdev_err(dev, + "bitrate error %d.%d%% too high\n", + bitrate_error / 10, bitrate_error % 10); + return -EDOM; + } + netdev_warn(dev, "bitrate error %d.%d%%\n", + bitrate_error / 10, bitrate_error % 10); + } + + /* real sample point */ + bt->sample_point = can_update_sample_point(btc, sample_point_nominal, + best_tseg, &tseg1, &tseg2, + NULL); + + v64 = (u64)best_brp * 1000 * 1000 * 1000; + do_div(v64, priv->clock.freq); + bt->tq = (u32)v64; + bt->prop_seg = tseg1 / 2; + bt->phase_seg1 = tseg1 - bt->prop_seg; + bt->phase_seg2 = tseg2; + + /* check for sjw user settings */ + if (!bt->sjw || !btc->sjw_max) { + bt->sjw = 1; + } else { + /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */ + if (bt->sjw > btc->sjw_max) + bt->sjw = btc->sjw_max; + /* bt->sjw must not be higher than tseg2 */ + if (tseg2 < bt->sjw) + bt->sjw = tseg2; + } + + bt->brp = best_brp; + + /* real bitrate */ + bt->bitrate = priv->clock.freq / + (bt->brp * (CAN_SYNC_SEG + tseg1 + tseg2)); + + return 0; +} + +void can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const, + const struct can_bittiming *dbt, + u32 *ctrlmode, u32 ctrlmode_supported) + +{ + if (!tdc_const || !(ctrlmode_supported & CAN_CTRLMODE_TDC_AUTO)) + return; + + *ctrlmode &= ~CAN_CTRLMODE_TDC_MASK; + + /* As specified in ISO 11898-1 section 11.3.3 "Transmitter + * delay compensation" (TDC) is only applicable if data BRP is + * one or two. + */ + if (dbt->brp == 1 || dbt->brp == 2) { + /* Sample point in clock periods */ + u32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg + + dbt->phase_seg1) * dbt->brp; + + if (sample_point_in_tc < tdc_const->tdco_min) + return; + tdc->tdco = min(sample_point_in_tc, tdc_const->tdco_max); + *ctrlmode |= CAN_CTRLMODE_TDC_AUTO; + } +} From bfe0092dc237963b035d8404ecd61d60f0ef1a5d Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:06 +0900 Subject: [PATCH 4/7] can: Kconfig: add CONFIG_CAN_RX_OFFLOAD Only a few drivers rely on the CAN rx offload framework (as of the writing of this patch, only four: flexcan, m_can, mcp251xfd and ti_hecc). Split it out of can-dev and add a new config symbol: CAN_RX_OFFLOAD. The drivers relying on CAN rx offload are in different sub folders. Make CAN_RX_OFFLOAD an hidden option and tag all the drivers depending on that feature with "select CAN_RX_OFFLOAD" so that the option gets automatically enabled if and only if one of those drivers is chosen. Link: https://lore.kernel.org/all/20220610143009.323579-5-mailhol.vincent@wanadoo.fr Suggested-by: Geert Uytterhoeven Suggested-by: Jakub Kicinski Signed-off-by: Vincent Mailhol Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/Kconfig | 5 +++++ drivers/net/can/dev/Makefile | 2 +- drivers/net/can/m_can/Kconfig | 1 + drivers/net/can/spi/mcp251xfd/Kconfig | 1 + 4 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig index 87470feae6b1..5335f3afc0a5 100644 --- a/drivers/net/can/Kconfig +++ b/drivers/net/can/Kconfig @@ -102,6 +102,9 @@ config CAN_CALC_BITTIMING If unsure, say Y. +config CAN_RX_OFFLOAD + bool + config CAN_AT91 tristate "Atmel AT91 onchip CAN controller" depends on (ARCH_AT91 || COMPILE_TEST) && HAS_IOMEM @@ -113,6 +116,7 @@ config CAN_FLEXCAN tristate "Support for Freescale FLEXCAN based chips" depends on OF || COLDFIRE || COMPILE_TEST depends on HAS_IOMEM + select CAN_RX_OFFLOAD help Say Y here if you want to support for Freescale FlexCAN. @@ -162,6 +166,7 @@ config CAN_SUN4I config CAN_TI_HECC depends on ARM tristate "TI High End CAN Controller" + select CAN_RX_OFFLOAD help Driver for TI HECC (High End CAN Controller) module found on many TI devices. The device specifications are available from www.ti.com diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile index 791e6b297ea3..633687d6b6c0 100644 --- a/drivers/net/can/dev/Makefile +++ b/drivers/net/can/dev/Makefile @@ -9,4 +9,4 @@ can-dev-$(CONFIG_CAN_NETLINK) += bittiming.o can-dev-$(CONFIG_CAN_NETLINK) += dev.o can-dev-$(CONFIG_CAN_NETLINK) += length.o can-dev-$(CONFIG_CAN_NETLINK) += netlink.o -can-dev-$(CONFIG_CAN_NETLINK) += rx-offload.o +can-dev-$(CONFIG_CAN_RX_OFFLOAD) += rx-offload.o diff --git a/drivers/net/can/m_can/Kconfig b/drivers/net/can/m_can/Kconfig index 45ad1b3f0cd0..fc2afab36279 100644 --- a/drivers/net/can/m_can/Kconfig +++ b/drivers/net/can/m_can/Kconfig @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only menuconfig CAN_M_CAN tristate "Bosch M_CAN support" + select CAN_RX_OFFLOAD help Say Y here if you want support for Bosch M_CAN controller framework. This is common support for devices that embed the Bosch M_CAN IP. diff --git a/drivers/net/can/spi/mcp251xfd/Kconfig b/drivers/net/can/spi/mcp251xfd/Kconfig index dd0fc0a54be1..877e4356010d 100644 --- a/drivers/net/can/spi/mcp251xfd/Kconfig +++ b/drivers/net/can/spi/mcp251xfd/Kconfig @@ -2,6 +2,7 @@ config CAN_MCP251XFD tristate "Microchip MCP251xFD SPI CAN controllers" + select CAN_RX_OFFLOAD select REGMAP select WANT_DEV_COREDUMP help From d7786af59860a113d62150c4328674e896da7810 Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:07 +0900 Subject: [PATCH 5/7] net: Kconfig: move the CAN device menu to the "Device Drivers" section The devices are meant to be under the "Device Drivers" category of the menuconfig. The CAN subsystem is currently one of the rare exception with all of its devices under the "Networking support" category. The CAN_DEV menuentry gets moved to fix this discrepancy. The CAN menu is added just before MCTP in order to be consistent with the current order under the "Networking support" menu. A dependency on CAN is added to CAN_DEV so that the CAN devices only show up if the CAN subsystem is enabled. Link: https://lore.kernel.org/all/20220610143009.323579-6-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/Kconfig | 2 ++ drivers/net/can/Kconfig | 1 + net/can/Kconfig | 5 ++--- 3 files changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index b2a4f998c180..5de243899de8 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -499,6 +499,8 @@ config NET_SB1000 source "drivers/net/phy/Kconfig" +source "drivers/net/can/Kconfig" + source "drivers/net/mctp/Kconfig" source "drivers/net/mdio/Kconfig" diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig index 5335f3afc0a5..806f15146f69 100644 --- a/drivers/net/can/Kconfig +++ b/drivers/net/can/Kconfig @@ -3,6 +3,7 @@ menuconfig CAN_DEV tristate "CAN Device Drivers" default y + depends on CAN help Controller Area Network (CAN) is serial communications protocol up to 1Mbit/s for its original release (now known as Classical CAN) and up diff --git a/net/can/Kconfig b/net/can/Kconfig index a9ac5ffab286..cb56be8e3862 100644 --- a/net/can/Kconfig +++ b/net/can/Kconfig @@ -15,7 +15,8 @@ menuconfig CAN PF_CAN is contained in . If you want CAN support you should say Y here and also to the - specific driver for your controller(s) below. + specific driver for your controller(s) under the Network device + support section. if CAN @@ -69,6 +70,4 @@ config CAN_ISOTP If you want to perform automotive vehicle diagnostic services (UDS), say 'y'. -source "drivers/net/can/Kconfig" - endif From ccd8a9351f7b44bc1c0c8e4d39c0d6593b106fc4 Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:08 +0900 Subject: [PATCH 6/7] can: skb: move can_dropped_invalid_skb() and can_skb_headroom_valid() to skb.c 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 Reported-by: kernel test robot Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/dev/skb.c | 58 ++++++++++++++++++++++++++++++++++++++ include/linux/can/skb.h | 59 +-------------------------------------- 2 files changed, 59 insertions(+), 58 deletions(-) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index a4208f125b76..dc9da76c0470 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -259,3 +259,61 @@ struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) return skb; } EXPORT_SYMBOL_GPL(alloc_can_err_skb); + +/* Check for outgoing skbs that have not been created by the CAN subsystem */ +static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb) +{ + /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */ + if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv))) + return false; + + /* af_packet does not apply CAN skb specific settings */ + if (skb->ip_summed == CHECKSUM_NONE) { + /* init headroom */ + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + + /* perform proper loopback on capable devices */ + if (dev->flags & IFF_ECHO) + skb->pkt_type = PACKET_LOOPBACK; + else + skb->pkt_type = PACKET_HOST; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + } + + return true; +} + +/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ +bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) +{ + 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; + } + + if (!can_skb_headroom_valid(dev, skb)) + goto inval_skb; + + return false; + +inval_skb: + kfree_skb(skb); + dev->stats.tx_dropped++; + return true; +} +EXPORT_SYMBOL_GPL(can_dropped_invalid_skb); diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h index fdb22b00674a..182749e858b3 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -31,6 +31,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev, struct canfd_frame **cfd); struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf); +bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb); /* * The struct can_skb_priv is used to transport additional information along @@ -96,64 +97,6 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb) return nskb; } -/* Check for outgoing skbs that have not been created by the CAN subsystem */ -static inline bool can_skb_headroom_valid(struct net_device *dev, - struct sk_buff *skb) -{ - /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */ - if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv))) - return false; - - /* af_packet does not apply CAN skb specific settings */ - if (skb->ip_summed == CHECKSUM_NONE) { - /* init headroom */ - can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; - - skb->ip_summed = CHECKSUM_UNNECESSARY; - - /* perform proper loopback on capable devices */ - if (dev->flags & IFF_ECHO) - skb->pkt_type = PACKET_LOOPBACK; - else - skb->pkt_type = PACKET_HOST; - - skb_reset_mac_header(skb); - skb_reset_network_header(skb); - skb_reset_transport_header(skb); - } - - return true; -} - -/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ -static inline bool can_dropped_invalid_skb(struct net_device *dev, - struct sk_buff *skb) -{ - 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; - - if (!can_skb_headroom_valid(dev, skb)) - goto inval_skb; - - return false; - -inval_skb: - kfree_skb(skb); - dev->stats.tx_dropped++; - return true; -} - static inline bool can_is_canfd_skb(const struct sk_buff *skb) { /* the CAN specific type of skb is identified by its data length */ From a6d190f8c7670068d8c154ef8477eca07b5e3574 Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Fri, 10 Jun 2022 23:30:09 +0900 Subject: [PATCH 7/7] can: skb: drop tx skb if in listen only mode Frames can be directly injected to a can driver via the packet socket. By doing so, it is possible to reach the net_device_ops::ndo_start_xmit function even if the driver is configured in listen only mode. Add a check in can_dropped_invalid_skb() to discard the skb if CAN_CTRLMODE_LISTENONLY is set. Link: https://lore.kernel.org/all/20220610143009.323579-8-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol Acked-by: Max Staudt Tested-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/dev/skb.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index dc9da76c0470..8bb62dd864c8 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -5,6 +5,7 @@ */ #include +#include #include #define MOD_DESC "CAN device driver interface" @@ -293,6 +294,7 @@ static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb) bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) { const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + struct can_priv *priv = netdev_priv(dev); if (skb->protocol == htons(ETH_P_CAN)) { if (unlikely(skb->len != CAN_MTU || @@ -306,8 +308,13 @@ bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) goto inval_skb; } - if (!can_skb_headroom_valid(dev, skb)) + if (!can_skb_headroom_valid(dev, skb)) { goto inval_skb; + } else if (priv->ctrlmode & CAN_CTRLMODE_LISTENONLY) { + netdev_info_once(dev, + "interface in listen only mode, dropping skb\n"); + goto inval_skb; + } return false;