| Message ID | 20210225215155.30509-6-dariobin@libero.it |
|---|---|
| State | Superseded |
| Headers | show |
| Series | can: c_can: add support to 64 message objects | expand |
On 25.02.2021 22:51:54, Dario Binacchi wrote: > As pointed by commit c0a9f4d396c9 ("can: c_can: Reduce register access") > the "driver casts the 16 message objects in stone, which is completely > braindead as contemporary hardware has up to 128 message objects". > > The patch prepares the module to extend the number of message objects > beyond the 32 currently managed. This was achieved by transforming the > constants used to manage RX/TX messages into variables without changing > the driver policy. > > Signed-off-by: Dario Binacchi <dariobin@libero.it> > Reported-by: kernel test robot <lkp@intel.com> > > --- > > Changes in v2: > - Fix compiling error reported by kernel test robot. > - Add Reported-by tag. > - Pass larger size to alloc_candev() routine to avoid an additional > memory allocation/deallocation. > > drivers/net/can/c_can/c_can.c | 50 ++++++++++++++++---------- > drivers/net/can/c_can/c_can.h | 23 ++++++------ > drivers/net/can/c_can/c_can_pci.c | 2 +- > drivers/net/can/c_can/c_can_platform.c | 2 +- > 4 files changed, 43 insertions(+), 34 deletions(-) > > diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c > index 7081cfaf62e2..df1ad6b3fd3b 100644 > --- a/drivers/net/can/c_can/c_can.c > +++ b/drivers/net/can/c_can/c_can.c > @@ -173,9 +173,6 @@ > /* Wait for ~1 sec for INIT bit */ > #define INIT_WAIT_MS 1000 > > -/* napi related */ > -#define C_CAN_NAPI_WEIGHT C_CAN_MSG_OBJ_RX_NUM > - > /* c_can lec values */ > enum c_can_lec_type { > LEC_NO_ERROR = 0, > @@ -325,7 +322,7 @@ static void c_can_setup_tx_object(struct net_device *dev, int iface, > * first, i.e. clear the MSGVAL flag in the arbiter. > */ > if (rtr != (bool)test_bit(idx, &priv->tx_dir)) { > - u32 obj = idx + C_CAN_MSG_OBJ_TX_FIRST; > + u32 obj = idx + priv->msg_obj_tx_first; > > c_can_inval_msg_object(dev, iface, obj); > change_bit(idx, &priv->tx_dir); > @@ -463,10 +460,10 @@ static netdev_tx_t c_can_start_xmit(struct sk_buff *skb, > * prioritized. The lowest buffer number wins. > */ > idx = fls(atomic_read(&priv->tx_active)); > - obj = idx + C_CAN_MSG_OBJ_TX_FIRST; > + obj = idx + priv->msg_obj_tx_first; > > /* If this is the last buffer, stop the xmit queue */ > - if (idx == C_CAN_MSG_OBJ_TX_NUM - 1) > + if (idx == priv->msg_obj_tx_num - 1) > netif_stop_queue(dev); > /* > * Store the message in the interface so we can call > @@ -549,17 +546,18 @@ static int c_can_set_bittiming(struct net_device *dev) > */ > static void c_can_configure_msg_objects(struct net_device *dev) > { > + struct c_can_priv *priv = netdev_priv(dev); > int i; > > /* first invalidate all message objects */ > - for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_NO_OF_OBJECTS; i++) > + for (i = priv->msg_obj_rx_first; i <= priv->msg_obj_num; i++) > c_can_inval_msg_object(dev, IF_RX, i); > > /* setup receive message objects */ > - for (i = C_CAN_MSG_OBJ_RX_FIRST; i < C_CAN_MSG_OBJ_RX_LAST; i++) > + for (i = priv->msg_obj_rx_first; i < priv->msg_obj_rx_last; i++) > c_can_setup_receive_object(dev, IF_RX, i, 0, 0, IF_MCONT_RCV); > > - c_can_setup_receive_object(dev, IF_RX, C_CAN_MSG_OBJ_RX_LAST, 0, 0, > + c_can_setup_receive_object(dev, IF_RX, priv->msg_obj_rx_last, 0, 0, > IF_MCONT_RCV_EOB); > } > > @@ -730,7 +728,7 @@ static void c_can_do_tx(struct net_device *dev) > while ((idx = ffs(pend))) { > idx--; > pend &= ~(1 << idx); > - obj = idx + C_CAN_MSG_OBJ_TX_FIRST; > + obj = idx + priv->msg_obj_tx_first; > c_can_inval_tx_object(dev, IF_TX, obj); > can_get_echo_skb(dev, idx, NULL); > bytes += priv->dlc[idx]; > @@ -740,7 +738,7 @@ static void c_can_do_tx(struct net_device *dev) > /* Clear the bits in the tx_active mask */ > atomic_sub(clr, &priv->tx_active); > > - if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1))) > + if (clr & (1 << (priv->msg_obj_tx_num - 1))) > netif_wake_queue(dev); > > if (pkts) { > @@ -755,11 +753,11 @@ static void c_can_do_tx(struct net_device *dev) > * raced with the hardware or failed to readout all upper > * objects in the last run due to quota limit. > */ > -static u32 c_can_adjust_pending(u32 pend) > +static u32 c_can_adjust_pending(u32 pend, u32 rx_mask) > { > u32 weight, lasts; > > - if (pend == RECEIVE_OBJECT_BITS) > + if (pend == rx_mask) > return pend; > > /* > @@ -862,8 +860,7 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) > * It is faster to read only one 16bit register. This is only possible > * for a maximum number of 16 objects. > */ > - BUILD_BUG_ON_MSG(C_CAN_MSG_OBJ_RX_LAST > 16, > - "Implementation does not support more message objects than 16"); > + WARN_ON(priv->msg_obj_rx_last > 16); > > while (quota > 0) { > if (!pend) { > @@ -874,7 +871,8 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) > * If the pending field has a gap, handle the > * bits above the gap first. > */ > - toread = c_can_adjust_pending(pend); > + toread = c_can_adjust_pending(pend, > + priv->msg_obj_rx_mask); > } else { > toread = pend; > } > @@ -1205,17 +1203,31 @@ static int c_can_close(struct net_device *dev) > return 0; > } > > -struct net_device *alloc_c_can_dev(void) > +struct net_device *alloc_c_can_dev(int msg_obj_num) > { > struct net_device *dev; > struct c_can_priv *priv; > + int msg_obj_tx_num = msg_obj_num / 2; > > - dev = alloc_candev(sizeof(struct c_can_priv), C_CAN_MSG_OBJ_TX_NUM); > + dev = alloc_candev(sizeof(*priv) + sizeof(u32) * msg_obj_tx_num, > + msg_obj_tx_num); > if (!dev) > return NULL; > > priv = netdev_priv(dev); > - netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT); > + priv->msg_obj_num = msg_obj_num; > + priv->msg_obj_rx_num = msg_obj_num - msg_obj_tx_num; > + priv->msg_obj_rx_first = 1; > + priv->msg_obj_rx_last = > + priv->msg_obj_rx_first + priv->msg_obj_rx_num - 1; > + priv->msg_obj_rx_mask = ((u64)1 << priv->msg_obj_rx_num) - 1; > + > + priv->msg_obj_tx_num = msg_obj_tx_num; > + priv->msg_obj_tx_first = priv->msg_obj_rx_last + 1; > + priv->msg_obj_tx_last = > + priv->msg_obj_tx_first + priv->msg_obj_tx_num - 1; > + > + netif_napi_add(dev, &priv->napi, c_can_poll, priv->msg_obj_rx_num); > > priv->dev = dev; > priv->can.bittiming_const = &c_can_bittiming_const; > diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h > index 90d3d2e7a086..22ae6077b489 100644 > --- a/drivers/net/can/c_can/c_can.h > +++ b/drivers/net/can/c_can/c_can.h > @@ -22,18 +22,7 @@ > #ifndef C_CAN_H > #define C_CAN_H > > -/* message object split */ > #define C_CAN_NO_OF_OBJECTS 32 > -#define C_CAN_MSG_OBJ_RX_NUM 16 > -#define C_CAN_MSG_OBJ_TX_NUM 16 > - > -#define C_CAN_MSG_OBJ_RX_FIRST 1 > -#define C_CAN_MSG_OBJ_RX_LAST (C_CAN_MSG_OBJ_RX_FIRST + \ > - C_CAN_MSG_OBJ_RX_NUM - 1) > - > -#define C_CAN_MSG_OBJ_TX_FIRST (C_CAN_MSG_OBJ_RX_LAST + 1) > - > -#define RECEIVE_OBJECT_BITS 0x0000ffff > > enum reg { > C_CAN_CTRL_REG = 0, > @@ -193,6 +182,14 @@ struct c_can_priv { > struct napi_struct napi; > struct net_device *dev; > struct device *device; > + int msg_obj_num; > + int msg_obj_rx_num; > + int msg_obj_tx_num; > + int msg_obj_rx_first; > + int msg_obj_rx_last; > + int msg_obj_tx_first; > + int msg_obj_tx_last; I think these should/could be unsigned int. > + u32 msg_obj_rx_mask; Is this variable big enough after you've extended the driver to use 64 mailboxes? If you want to support 128 message objects converting the driver to the linux bitmap API is another option. Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
On 25.02.2021 22:51:54, Dario Binacchi wrote: > --- a/drivers/net/can/c_can/c_can.c > +++ b/drivers/net/can/c_can/c_can.c [...] > -struct net_device *alloc_c_can_dev(void) > +struct net_device *alloc_c_can_dev(int msg_obj_num) > { > struct net_device *dev; > struct c_can_priv *priv; > + int msg_obj_tx_num = msg_obj_num / 2; > > - dev = alloc_candev(sizeof(struct c_can_priv), C_CAN_MSG_OBJ_TX_NUM); > + dev = alloc_candev(sizeof(*priv) + sizeof(u32) * msg_obj_tx_num, > + msg_obj_tx_num); > if (!dev) > return NULL; > > priv = netdev_priv(dev); > - netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT); > + priv->msg_obj_num = msg_obj_num; > + priv->msg_obj_rx_num = msg_obj_num - msg_obj_tx_num; > + priv->msg_obj_rx_first = 1; > + priv->msg_obj_rx_last = > + priv->msg_obj_rx_first + priv->msg_obj_rx_num - 1; > + priv->msg_obj_rx_mask = ((u64)1 << priv->msg_obj_rx_num) - 1; Here you're casting the 1 to 64bit, but msg_obj_rx_mask is only u32. Use "1UL", if you are sure that rx_mask would never exceed 32 bit. Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
Hi Marc, > Il 26/02/2021 09:33 Marc Kleine-Budde <mkl@pengutronix.de> ha scritto: > > > On 25.02.2021 22:51:54, Dario Binacchi wrote: > > As pointed by commit c0a9f4d396c9 ("can: c_can: Reduce register access") > > the "driver casts the 16 message objects in stone, which is completely > > braindead as contemporary hardware has up to 128 message objects". > > > > The patch prepares the module to extend the number of message objects > > beyond the 32 currently managed. This was achieved by transforming the > > constants used to manage RX/TX messages into variables without changing > > the driver policy. > > > > Signed-off-by: Dario Binacchi <dariobin@libero.it> > > Reported-by: kernel test robot <lkp@intel.com> > > > > --- > > > > Changes in v2: > > - Fix compiling error reported by kernel test robot. > > - Add Reported-by tag. > > - Pass larger size to alloc_candev() routine to avoid an additional > > memory allocation/deallocation. > > > > drivers/net/can/c_can/c_can.c | 50 ++++++++++++++++---------- > > drivers/net/can/c_can/c_can.h | 23 ++++++------ > > drivers/net/can/c_can/c_can_pci.c | 2 +- > > drivers/net/can/c_can/c_can_platform.c | 2 +- > > 4 files changed, 43 insertions(+), 34 deletions(-) > > > > diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c > > index 7081cfaf62e2..df1ad6b3fd3b 100644 > > --- a/drivers/net/can/c_can/c_can.c > > +++ b/drivers/net/can/c_can/c_can.c > > @@ -173,9 +173,6 @@ > > /* Wait for ~1 sec for INIT bit */ > > #define INIT_WAIT_MS 1000 > > > > -/* napi related */ > > -#define C_CAN_NAPI_WEIGHT C_CAN_MSG_OBJ_RX_NUM > > - > > /* c_can lec values */ > > enum c_can_lec_type { > > LEC_NO_ERROR = 0, > > @@ -325,7 +322,7 @@ static void c_can_setup_tx_object(struct net_device *dev, int iface, > > * first, i.e. clear the MSGVAL flag in the arbiter. > > */ > > if (rtr != (bool)test_bit(idx, &priv->tx_dir)) { > > - u32 obj = idx + C_CAN_MSG_OBJ_TX_FIRST; > > + u32 obj = idx + priv->msg_obj_tx_first; > > > > c_can_inval_msg_object(dev, iface, obj); > > change_bit(idx, &priv->tx_dir); > > @@ -463,10 +460,10 @@ static netdev_tx_t c_can_start_xmit(struct sk_buff *skb, > > * prioritized. The lowest buffer number wins. > > */ > > idx = fls(atomic_read(&priv->tx_active)); > > - obj = idx + C_CAN_MSG_OBJ_TX_FIRST; > > + obj = idx + priv->msg_obj_tx_first; > > > > /* If this is the last buffer, stop the xmit queue */ > > - if (idx == C_CAN_MSG_OBJ_TX_NUM - 1) > > + if (idx == priv->msg_obj_tx_num - 1) > > netif_stop_queue(dev); > > /* > > * Store the message in the interface so we can call > > @@ -549,17 +546,18 @@ static int c_can_set_bittiming(struct net_device *dev) > > */ > > static void c_can_configure_msg_objects(struct net_device *dev) > > { > > + struct c_can_priv *priv = netdev_priv(dev); > > int i; > > > > /* first invalidate all message objects */ > > - for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_NO_OF_OBJECTS; i++) > > + for (i = priv->msg_obj_rx_first; i <= priv->msg_obj_num; i++) > > c_can_inval_msg_object(dev, IF_RX, i); > > > > /* setup receive message objects */ > > - for (i = C_CAN_MSG_OBJ_RX_FIRST; i < C_CAN_MSG_OBJ_RX_LAST; i++) > > + for (i = priv->msg_obj_rx_first; i < priv->msg_obj_rx_last; i++) > > c_can_setup_receive_object(dev, IF_RX, i, 0, 0, IF_MCONT_RCV); > > > > - c_can_setup_receive_object(dev, IF_RX, C_CAN_MSG_OBJ_RX_LAST, 0, 0, > > + c_can_setup_receive_object(dev, IF_RX, priv->msg_obj_rx_last, 0, 0, > > IF_MCONT_RCV_EOB); > > } > > > > @@ -730,7 +728,7 @@ static void c_can_do_tx(struct net_device *dev) > > while ((idx = ffs(pend))) { > > idx--; > > pend &= ~(1 << idx); > > - obj = idx + C_CAN_MSG_OBJ_TX_FIRST; > > + obj = idx + priv->msg_obj_tx_first; > > c_can_inval_tx_object(dev, IF_TX, obj); > > can_get_echo_skb(dev, idx, NULL); > > bytes += priv->dlc[idx]; > > @@ -740,7 +738,7 @@ static void c_can_do_tx(struct net_device *dev) > > /* Clear the bits in the tx_active mask */ > > atomic_sub(clr, &priv->tx_active); > > > > - if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1))) > > + if (clr & (1 << (priv->msg_obj_tx_num - 1))) > > netif_wake_queue(dev); > > > > if (pkts) { > > @@ -755,11 +753,11 @@ static void c_can_do_tx(struct net_device *dev) > > * raced with the hardware or failed to readout all upper > > * objects in the last run due to quota limit. > > */ > > -static u32 c_can_adjust_pending(u32 pend) > > +static u32 c_can_adjust_pending(u32 pend, u32 rx_mask) > > { > > u32 weight, lasts; > > > > - if (pend == RECEIVE_OBJECT_BITS) > > + if (pend == rx_mask) > > return pend; > > > > /* > > @@ -862,8 +860,7 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) > > * It is faster to read only one 16bit register. This is only possible > > * for a maximum number of 16 objects. > > */ > > - BUILD_BUG_ON_MSG(C_CAN_MSG_OBJ_RX_LAST > 16, > > - "Implementation does not support more message objects than 16"); > > + WARN_ON(priv->msg_obj_rx_last > 16); > > > > while (quota > 0) { > > if (!pend) { > > @@ -874,7 +871,8 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) > > * If the pending field has a gap, handle the > > * bits above the gap first. > > */ > > - toread = c_can_adjust_pending(pend); > > + toread = c_can_adjust_pending(pend, > > + priv->msg_obj_rx_mask); > > } else { > > toread = pend; > > } > > @@ -1205,17 +1203,31 @@ static int c_can_close(struct net_device *dev) > > return 0; > > } > > > > -struct net_device *alloc_c_can_dev(void) > > +struct net_device *alloc_c_can_dev(int msg_obj_num) > > { > > struct net_device *dev; > > struct c_can_priv *priv; > > + int msg_obj_tx_num = msg_obj_num / 2; > > > > - dev = alloc_candev(sizeof(struct c_can_priv), C_CAN_MSG_OBJ_TX_NUM); > > + dev = alloc_candev(sizeof(*priv) + sizeof(u32) * msg_obj_tx_num, > > + msg_obj_tx_num); > > if (!dev) > > return NULL; > > > > priv = netdev_priv(dev); > > - netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT); > > + priv->msg_obj_num = msg_obj_num; > > + priv->msg_obj_rx_num = msg_obj_num - msg_obj_tx_num; > > + priv->msg_obj_rx_first = 1; > > + priv->msg_obj_rx_last = > > + priv->msg_obj_rx_first + priv->msg_obj_rx_num - 1; > > + priv->msg_obj_rx_mask = ((u64)1 << priv->msg_obj_rx_num) - 1; > > + > > + priv->msg_obj_tx_num = msg_obj_tx_num; > > + priv->msg_obj_tx_first = priv->msg_obj_rx_last + 1; > > + priv->msg_obj_tx_last = > > + priv->msg_obj_tx_first + priv->msg_obj_tx_num - 1; > > + > > + netif_napi_add(dev, &priv->napi, c_can_poll, priv->msg_obj_rx_num); > > > > priv->dev = dev; > > priv->can.bittiming_const = &c_can_bittiming_const; > > diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h > > index 90d3d2e7a086..22ae6077b489 100644 > > --- a/drivers/net/can/c_can/c_can.h > > +++ b/drivers/net/can/c_can/c_can.h > > @@ -22,18 +22,7 @@ > > #ifndef C_CAN_H > > #define C_CAN_H > > > > -/* message object split */ > > #define C_CAN_NO_OF_OBJECTS 32 > > -#define C_CAN_MSG_OBJ_RX_NUM 16 > > -#define C_CAN_MSG_OBJ_TX_NUM 16 > > - > > -#define C_CAN_MSG_OBJ_RX_FIRST 1 > > -#define C_CAN_MSG_OBJ_RX_LAST (C_CAN_MSG_OBJ_RX_FIRST + \ > > - C_CAN_MSG_OBJ_RX_NUM - 1) > > - > > -#define C_CAN_MSG_OBJ_TX_FIRST (C_CAN_MSG_OBJ_RX_LAST + 1) > > - > > -#define RECEIVE_OBJECT_BITS 0x0000ffff > > > > enum reg { > > C_CAN_CTRL_REG = 0, > > @@ -193,6 +182,14 @@ struct c_can_priv { > > struct napi_struct napi; > > struct net_device *dev; > > struct device *device; > > + int msg_obj_num; > > + int msg_obj_rx_num; > > + int msg_obj_tx_num; > > + int msg_obj_rx_first; > > + int msg_obj_rx_last; > > + int msg_obj_tx_first; > > + int msg_obj_tx_last; > > I think these should/could be unsigned int. > > > + u32 msg_obj_rx_mask; > > Is this variable big enough after you've extended the driver to use 64 > mailboxes? Yes. I have kept the message assignment policy unchanged, they are equally divided between reception and transmission. Therefore, in the case of 64 messages, 32 are used for reception and 32 for transmission. So a 32-bit variable is enough. > > If you want to support 128 message objects converting the driver to the > linux bitmap API is another option. > Do you know if any of the hardware managed by Linux use a D_CAN controller with 128 message objects? Thanks and regards, Dario > Marc > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Embedded Linux | https://www.pengutronix.de | > Vertretung West/Dortmund | Phone: +49-231-2826-924 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
On 28.02.2021 11:18:13, Dario Binacchi wrote: > > > + u32 msg_obj_rx_mask; > > > > Is this variable big enough after you've extended the driver to use 64 > > mailboxes? > > Yes. I have kept the message assignment policy unchanged, they are equally > divided between reception and transmission. Therefore, in the case of 64 > messages, 32 are used for reception and 32 for transmission. So a 32-bit > variable is enough. > > > > > If you want to support 128 message objects converting the driver to the > > linux bitmap API is another option. > > > > Do you know if any of the hardware managed by Linux use a D_CAN controller > with 128 message objects? Even the am437x only uses 64 message objects. Ok let's stay with 64 as max for now. regards, Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c index 7081cfaf62e2..df1ad6b3fd3b 100644 --- a/drivers/net/can/c_can/c_can.c +++ b/drivers/net/can/c_can/c_can.c @@ -173,9 +173,6 @@ /* Wait for ~1 sec for INIT bit */ #define INIT_WAIT_MS 1000 -/* napi related */ -#define C_CAN_NAPI_WEIGHT C_CAN_MSG_OBJ_RX_NUM - /* c_can lec values */ enum c_can_lec_type { LEC_NO_ERROR = 0, @@ -325,7 +322,7 @@ static void c_can_setup_tx_object(struct net_device *dev, int iface, * first, i.e. clear the MSGVAL flag in the arbiter. */ if (rtr != (bool)test_bit(idx, &priv->tx_dir)) { - u32 obj = idx + C_CAN_MSG_OBJ_TX_FIRST; + u32 obj = idx + priv->msg_obj_tx_first; c_can_inval_msg_object(dev, iface, obj); change_bit(idx, &priv->tx_dir); @@ -463,10 +460,10 @@ static netdev_tx_t c_can_start_xmit(struct sk_buff *skb, * prioritized. The lowest buffer number wins. */ idx = fls(atomic_read(&priv->tx_active)); - obj = idx + C_CAN_MSG_OBJ_TX_FIRST; + obj = idx + priv->msg_obj_tx_first; /* If this is the last buffer, stop the xmit queue */ - if (idx == C_CAN_MSG_OBJ_TX_NUM - 1) + if (idx == priv->msg_obj_tx_num - 1) netif_stop_queue(dev); /* * Store the message in the interface so we can call @@ -549,17 +546,18 @@ static int c_can_set_bittiming(struct net_device *dev) */ static void c_can_configure_msg_objects(struct net_device *dev) { + struct c_can_priv *priv = netdev_priv(dev); int i; /* first invalidate all message objects */ - for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_NO_OF_OBJECTS; i++) + for (i = priv->msg_obj_rx_first; i <= priv->msg_obj_num; i++) c_can_inval_msg_object(dev, IF_RX, i); /* setup receive message objects */ - for (i = C_CAN_MSG_OBJ_RX_FIRST; i < C_CAN_MSG_OBJ_RX_LAST; i++) + for (i = priv->msg_obj_rx_first; i < priv->msg_obj_rx_last; i++) c_can_setup_receive_object(dev, IF_RX, i, 0, 0, IF_MCONT_RCV); - c_can_setup_receive_object(dev, IF_RX, C_CAN_MSG_OBJ_RX_LAST, 0, 0, + c_can_setup_receive_object(dev, IF_RX, priv->msg_obj_rx_last, 0, 0, IF_MCONT_RCV_EOB); } @@ -730,7 +728,7 @@ static void c_can_do_tx(struct net_device *dev) while ((idx = ffs(pend))) { idx--; pend &= ~(1 << idx); - obj = idx + C_CAN_MSG_OBJ_TX_FIRST; + obj = idx + priv->msg_obj_tx_first; c_can_inval_tx_object(dev, IF_TX, obj); can_get_echo_skb(dev, idx, NULL); bytes += priv->dlc[idx]; @@ -740,7 +738,7 @@ static void c_can_do_tx(struct net_device *dev) /* Clear the bits in the tx_active mask */ atomic_sub(clr, &priv->tx_active); - if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1))) + if (clr & (1 << (priv->msg_obj_tx_num - 1))) netif_wake_queue(dev); if (pkts) { @@ -755,11 +753,11 @@ static void c_can_do_tx(struct net_device *dev) * raced with the hardware or failed to readout all upper * objects in the last run due to quota limit. */ -static u32 c_can_adjust_pending(u32 pend) +static u32 c_can_adjust_pending(u32 pend, u32 rx_mask) { u32 weight, lasts; - if (pend == RECEIVE_OBJECT_BITS) + if (pend == rx_mask) return pend; /* @@ -862,8 +860,7 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) * It is faster to read only one 16bit register. This is only possible * for a maximum number of 16 objects. */ - BUILD_BUG_ON_MSG(C_CAN_MSG_OBJ_RX_LAST > 16, - "Implementation does not support more message objects than 16"); + WARN_ON(priv->msg_obj_rx_last > 16); while (quota > 0) { if (!pend) { @@ -874,7 +871,8 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) * If the pending field has a gap, handle the * bits above the gap first. */ - toread = c_can_adjust_pending(pend); + toread = c_can_adjust_pending(pend, + priv->msg_obj_rx_mask); } else { toread = pend; } @@ -1205,17 +1203,31 @@ static int c_can_close(struct net_device *dev) return 0; } -struct net_device *alloc_c_can_dev(void) +struct net_device *alloc_c_can_dev(int msg_obj_num) { struct net_device *dev; struct c_can_priv *priv; + int msg_obj_tx_num = msg_obj_num / 2; - dev = alloc_candev(sizeof(struct c_can_priv), C_CAN_MSG_OBJ_TX_NUM); + dev = alloc_candev(sizeof(*priv) + sizeof(u32) * msg_obj_tx_num, + msg_obj_tx_num); if (!dev) return NULL; priv = netdev_priv(dev); - netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT); + priv->msg_obj_num = msg_obj_num; + priv->msg_obj_rx_num = msg_obj_num - msg_obj_tx_num; + priv->msg_obj_rx_first = 1; + priv->msg_obj_rx_last = + priv->msg_obj_rx_first + priv->msg_obj_rx_num - 1; + priv->msg_obj_rx_mask = ((u64)1 << priv->msg_obj_rx_num) - 1; + + priv->msg_obj_tx_num = msg_obj_tx_num; + priv->msg_obj_tx_first = priv->msg_obj_rx_last + 1; + priv->msg_obj_tx_last = + priv->msg_obj_tx_first + priv->msg_obj_tx_num - 1; + + netif_napi_add(dev, &priv->napi, c_can_poll, priv->msg_obj_rx_num); priv->dev = dev; priv->can.bittiming_const = &c_can_bittiming_const; diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h index 90d3d2e7a086..22ae6077b489 100644 --- a/drivers/net/can/c_can/c_can.h +++ b/drivers/net/can/c_can/c_can.h @@ -22,18 +22,7 @@ #ifndef C_CAN_H #define C_CAN_H -/* message object split */ #define C_CAN_NO_OF_OBJECTS 32 -#define C_CAN_MSG_OBJ_RX_NUM 16 -#define C_CAN_MSG_OBJ_TX_NUM 16 - -#define C_CAN_MSG_OBJ_RX_FIRST 1 -#define C_CAN_MSG_OBJ_RX_LAST (C_CAN_MSG_OBJ_RX_FIRST + \ - C_CAN_MSG_OBJ_RX_NUM - 1) - -#define C_CAN_MSG_OBJ_TX_FIRST (C_CAN_MSG_OBJ_RX_LAST + 1) - -#define RECEIVE_OBJECT_BITS 0x0000ffff enum reg { C_CAN_CTRL_REG = 0, @@ -193,6 +182,14 @@ struct c_can_priv { struct napi_struct napi; struct net_device *dev; struct device *device; + int msg_obj_num; + int msg_obj_rx_num; + int msg_obj_tx_num; + int msg_obj_rx_first; + int msg_obj_rx_last; + int msg_obj_tx_first; + int msg_obj_tx_last; + u32 msg_obj_rx_mask; atomic_t tx_active; atomic_t sie_pending; unsigned long tx_dir; @@ -209,10 +206,10 @@ struct c_can_priv { void (*raminit) (const struct c_can_priv *priv, bool enable); u32 comm_rcv_high; u32 rxmasked; - u32 dlc[C_CAN_MSG_OBJ_TX_NUM]; + u32 dlc[]; }; -struct net_device *alloc_c_can_dev(void); +struct net_device *alloc_c_can_dev(int msg_obj_num); void free_c_can_dev(struct net_device *dev); int register_c_can_dev(struct net_device *dev); void unregister_c_can_dev(struct net_device *dev); diff --git a/drivers/net/can/c_can/c_can_pci.c b/drivers/net/can/c_can/c_can_pci.c index 406b4847e5dc..3752f68d095e 100644 --- a/drivers/net/can/c_can/c_can_pci.c +++ b/drivers/net/can/c_can/c_can_pci.c @@ -149,7 +149,7 @@ static int c_can_pci_probe(struct pci_dev *pdev, } /* allocate the c_can device */ - dev = alloc_c_can_dev(); + dev = alloc_c_can_dev(C_CAN_NO_OF_OBJECTS); if (!dev) { ret = -ENOMEM; goto out_iounmap; diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c index 05f425ceb53a..a5b9b1a93702 100644 --- a/drivers/net/can/c_can/c_can_platform.c +++ b/drivers/net/can/c_can/c_can_platform.c @@ -293,7 +293,7 @@ static int c_can_plat_probe(struct platform_device *pdev) } /* allocate the c_can device */ - dev = alloc_c_can_dev(); + dev = alloc_c_can_dev(C_CAN_NO_OF_OBJECTS); if (!dev) { ret = -ENOMEM; goto exit;
As pointed by commit c0a9f4d396c9 ("can: c_can: Reduce register access") the "driver casts the 16 message objects in stone, which is completely braindead as contemporary hardware has up to 128 message objects". The patch prepares the module to extend the number of message objects beyond the 32 currently managed. This was achieved by transforming the constants used to manage RX/TX messages into variables without changing the driver policy. Signed-off-by: Dario Binacchi <dariobin@libero.it> Reported-by: kernel test robot <lkp@intel.com> --- Changes in v2: - Fix compiling error reported by kernel test robot. - Add Reported-by tag. - Pass larger size to alloc_candev() routine to avoid an additional memory allocation/deallocation. drivers/net/can/c_can/c_can.c | 50 ++++++++++++++++---------- drivers/net/can/c_can/c_can.h | 23 ++++++------ drivers/net/can/c_can/c_can_pci.c | 2 +- drivers/net/can/c_can/c_can_platform.c | 2 +- 4 files changed, 43 insertions(+), 34 deletions(-)