[v1,1/6] net/can: Initial host SocketCan support for CAN FD.

Commit Message

Pavel Pisa July 14, 2020, 12:20 p.m. UTC

From: Jan Charvat <[e-mail]>

Signed-off-by: Jan Charvat <[e-mail]>
Signed-off-by: Pavel Pisa <[e-mail]>
---
 hw/net/can/can_sja1000.c |  2 ++
 include/net/can_emu.h    |  8 ++++++-
 net/can/can_socketcan.c  | 47 +++++++++++++++++++++++++++++++++++++---
 3 files changed, 53 insertions(+), 4 deletions(-)

Comments

Vikram Garhwal Sept. 1, 2020, 8:01 p.m. UTC | #1

Hi Jan,
A couple of comments on this patch.
On Tue, Jul 14, 2020 at 02:20:14PM +0200, [e-mail] wrote:
> From: Jan Charvat <[e-mail]>
>
> Signed-off-by: Jan Charvat <[e-mail]>
> Signed-off-by: Pavel Pisa <[e-mail]>
> ---
>  hw/net/can/can_sja1000.c |  2 ++
>  include/net/can_emu.h    |  8 ++++++-
>  net/can/can_socketcan.c  | 47 +++++++++++++++++++++++++++++++++++++---
>  3 files changed, 53 insertions(+), 4 deletions(-)
>
> diff --git a/hw/net/can/can_sja1000.c b/hw/net/can/can_sja1000.c
> index ea915a023a..d83c550edc 100644
> --- a/hw/net/can/can_sja1000.c
> +++ b/hw/net/can/can_sja1000.c
> @@ -268,6 +268,7 @@ static void buff2frame_pel(const uint8_t *buff, qemu_can_frame *frame)
>  {
>      uint8_t i;
>
> +    frame->flags = 0;
>      frame->can_id = 0;
>      if (buff[0] & 0x40) { /* RTR */
>          frame->can_id = QEMU_CAN_RTR_FLAG;
> @@ -303,6 +304,7 @@ static void buff2frame_bas(const uint8_t *buff, qemu_can_frame *frame)
>  {
>      uint8_t i;
>
> +    frame->flags = 0;
>      frame->can_id = ((buff[0] << 3) & (0xff << 3)) + ((buff[1] >> 5) & 0x07);
>      if (buff[1] & 0x10) { /* RTR */
>          frame->can_id = QEMU_CAN_RTR_FLAG;
> diff --git a/include/net/can_emu.h b/include/net/can_emu.h
> index fce9770928..c6164dcfb4 100644
> --- a/include/net/can_emu.h
> +++ b/include/net/can_emu.h
> @@ -46,7 +46,8 @@ typedef uint32_t qemu_canid_t;
>  typedef struct qemu_can_frame {
>      qemu_canid_t    can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
>      uint8_t         can_dlc; /* data length code: 0 .. 8 */
> -    uint8_t         data[8] QEMU_ALIGNED(8);
> +    uint8_t         flags;
> +    uint8_t         data[64] QEMU_ALIGNED(8);
>  } qemu_can_frame;
>
>  /* Keep defines for QEMU separate from Linux ones for now */
> @@ -58,6 +59,10 @@ typedef struct qemu_can_frame {
>  #define QEMU_CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
>  #define QEMU_CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
>
> +#define QEMU_CAN_FRMF_BRS     0x01 /* bit rate switch (2nd bitrate for data) */
> +#define QEMU_CAN_FRMF_ESI     0x02 /* error state ind. of transmitting node */
> +#define QEMU_CAN_FRMF_TYPE_FD 0x10 /* internal bit ind. of CAN FD frame */
> +
>  /**
>   * struct qemu_can_filter - CAN ID based filter in can_register().
>   * @can_id:   relevant bits of CAN ID which are not masked out.
> @@ -97,6 +102,7 @@ struct CanBusClientState {
>      char *model;
>      char *name;
>      void (*destructor)(CanBusClientState *);
> +    bool fd_mode;
>  };
>
>  #define TYPE_CAN_BUS "can-bus"
> diff --git a/net/can/can_socketcan.c b/net/can/can_socketcan.c
> index b7ef63ec0e..fbc0b62ea4 100644
> --- a/net/can/can_socketcan.c
> +++ b/net/can/can_socketcan.c
> @@ -103,6 +103,14 @@ static void can_host_socketcan_read(void *opaque)
>          return;
>      }
>
> +    if (!ch->bus_client.fd_mode) {
> +        c->buf[0].flags = 0;
> +    } else {
> +        if (c->bufcnt > CAN_MTU) {
> +            c->buf[0].flags |= QEMU_CAN_FRMF_TYPE_FD;
> +        }
> +    }
> +
>      can_bus_client_send(&ch->bus_client, c->buf, 1);
>
>      if (DEBUG_CAN) {
> @@ -121,12 +129,21 @@ static ssize_t can_host_socketcan_receive(CanBusClientState *client,
>      CanHostState *ch = container_of(client, CanHostState, bus_client);
>      CanHostSocketCAN *c = CAN_HOST_SOCKETCAN(ch);
>
> -    size_t len = sizeof(qemu_can_frame);
> +    size_t len;
>      int res;
>
>      if (c->fd < 0) {
>          return -1;
>      }
> +    if (frames->flags & QEMU_CAN_FRMF_TYPE_FD) {
> +        if (!ch->bus_client.fd_mode) {
> +            return 0;
> +        }
> +        len = CANFD_MTU;
> +    } else {
> +        len = CAN_MTU;
> +
> +    }
>
>      res = write(c->fd, frames, len);
>
> @@ -172,6 +189,8 @@ static void can_host_socketcan_connect(CanHostState *ch, Error **errp)
>  {
>      CanHostSocketCAN *c = CAN_HOST_SOCKETCAN(ch);
>      int s; /* can raw socket */
> +    int mtu;
> +    int enable_canfd = 1;
>      struct sockaddr_can addr;
>      struct ifreq ifr;
>
> @@ -185,13 +204,34 @@ static void can_host_socketcan_connect(CanHostState *ch, Error **errp)
>      addr.can_family = AF_CAN;
>      memset(&ifr.ifr_name, 0, sizeof(ifr.ifr_name));
>      strcpy(ifr.ifr_name, c->ifname);
> +    /* check if the frame fits into the CAN netdevice */
>      if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
>          error_setg_errno(errp, errno,
> -                         "SocketCAN host interface %s not available", c->ifname);
> +                         "SocketCAN host interface %s not available",
> +                         c->ifname);
May be this formatting change in a different patch? As this is not related to
CANFD.
>          goto fail;
>      }
>      addr.can_ifindex = ifr.ifr_ifindex;
>
> +    if (ioctl(s, SIOCGIFMTU, &ifr) < 0) {
> +        error_setg_errno(errp, errno,
> +                         "SocketCAN host interface %s SIOCGIFMTU failed",
> +                         c->ifname);
> +        goto fail;
> +    }
> +    mtu = ifr.ifr_mtu;
> +
> +    if (mtu >= CANFD_MTU) {
> +        /* interface is ok - try to switch the socket into CAN FD mode */
> +        if (setsockopt(s, SOL_CAN_RAW, CAN_RAW_FD_FRAMES,
> +                        &enable_canfd, sizeof(enable_canfd))) {
> +            warn_report("SocketCAN host interface %s enabling CAN FD failed",
> +                        c->ifname);
> +        } else {
> +            c->parent.bus_client.fd_mode = true;
> +        }
> +    }
> +
>      c->err_mask = 0xffffffff; /* Receive error frame. */
>      setsockopt(s, SOL_CAN_RAW, CAN_RAW_ERR_FILTER,
>                     &c->err_mask, sizeof(c->err_mask));
> @@ -232,7 +272,8 @@ static char *can_host_socketcan_get_if(Object *obj, Error **errp)
>      return g_strdup(c->ifname);
>  }
>
> -static void can_host_socketcan_set_if(Object *obj, const char *value, Error **errp)
> +static void can_host_socketcan_set_if(Object *obj, const char *value,
> +                                      Error **errp)
This one also not relevant change for CANFD. Rest of the patch looks good.
>  {
>      CanHostSocketCAN *c = CAN_HOST_SOCKETCAN(obj);
>      struct ifreq ifr;
> --
> 2.20.1
>
>

Pavel Pisa Sept. 2, 2020, 7:51 a.m. UTC | #2

Hello Vikram,

thanks much for the patches review.

On Tuesday 01 of September 2020 22:01:26 Vikram Garhwal wrote:
> Hi Jan,
> A couple of comments on this patch.
>
> On Tue, Jul 14, 2020 at 02:20:14PM +0200, [e-mail] wrote:
> > From: Jan Charvat <[e-mail]>
> > @@ -185,13 +204,34 @@ static void can_host_socketcan_connect(CanHostState
> > *ch, Error **errp) addr.can_family = AF_CAN;
> >      memset(&ifr.ifr_name, 0, sizeof(ifr.ifr_name));
> >      strcpy(ifr.ifr_name, c->ifname);
> > +    /* check if the frame fits into the CAN netdevice */
> >      if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
> >          error_setg_errno(errp, errno,
> > -                         "SocketCAN host interface %s not available",
> > c->ifname); +                         "SocketCAN host interface %s not
> > available", +                         c->ifname);
>
> May be this formatting change in a different patch? As this is not related
> to CANFD.
> > @@ -232,7 +272,8 @@ static char *can_host_socketcan_get_if(Object *obj,
> > Error **errp) return g_strdup(c->ifname);
> >  }
> >
> > -static void can_host_socketcan_set_if(Object *obj, const char *value,
> > Error **errp) +static void can_host_socketcan_set_if(Object *obj, const
> > char *value,
> > +                                      Error **errp) 
>
> This one also not relevant change for CANFD. Rest of the patch looks good.


I am responsible for mentioned lines change in net/can/can_socketcan.c.
When I have reviewed patches after Jan Charvat theses submittion,
I have done another bunch of rounds to check that the patches as well
as the whole net/can and hw/net/can are checkpatch clean. I am not sure
if the incorrect formatting sneaked in in my 2018 submission or patcheck
became more strict last years.

I can separate these changes changes into separate patch if required.

By the way, if you or other of your colleagues is willing to participate
in net/can and or  hw/net/can patches reviews, I would be happy if you
join my attempt and we can record that we are available to take care
abut these in MAINTAINERS file.

Best wishes,

Pavel

Vikram Garhwal Sept. 3, 2020, 5:20 a.m. UTC | #3

On Wed, Sep 02, 2020 at 09:51:44AM +0200, Pavel Pisa wrote:
Hi Pavel,
> Hello Vikram,
>
> thanks much for the patches review.
>
> On Tuesday 01 of September 2020 22:01:26 Vikram Garhwal wrote:
> > Hi Jan,
> > A couple of comments on this patch.
> >
> > On Tue, Jul 14, 2020 at 02:20:14PM +0200, [e-mail] wrote:
> > > From: Jan Charvat <[e-mail]>
> > > @@ -185,13 +204,34 @@ static void can_host_socketcan_connect(CanHostState
> > > *ch, Error **errp) addr.can_family = AF_CAN;
> > >      memset(&ifr.ifr_name, 0, sizeof(ifr.ifr_name));
> > >      strcpy(ifr.ifr_name, c->ifname);
> > > +    /* check if the frame fits into the CAN netdevice */
> > >      if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
> > >          error_setg_errno(errp, errno,
> > > -                         "SocketCAN host interface %s not available",
> > > c->ifname); +                         "SocketCAN host interface %s not
> > > available", +                         c->ifname);
> >
> > May be this formatting change in a different patch? As this is not related
> > to CANFD.
> > > @@ -232,7 +272,8 @@ static char *can_host_socketcan_get_if(Object *obj,
> > > Error **errp) return g_strdup(c->ifname);
> > >  }
> > >
> > > -static void can_host_socketcan_set_if(Object *obj, const char *value,
> > > Error **errp) +static void can_host_socketcan_set_if(Object *obj, const
> > > char *value,
> > > +                                      Error **errp)
> >
> > This one also not relevant change for CANFD. Rest of the patch looks good.
>
>
> I am responsible for mentioned lines change in net/can/can_socketcan.c.
> When I have reviewed patches after Jan Charvat theses submittion,
> I have done another bunch of rounds to check that the patches as well
> as the whole net/can and hw/net/can are checkpatch clean. I am not sure
> if the incorrect formatting sneaked in in my 2018 submission or patcheck
> became more strict last years.
>
> I can separate these changes changes into separate patch if required.
May be we can keep them in same patch. I was just referring to "Don't include irrelevant changes" section on this page about patches: https://wiki.qemu.org/Contribute/SubmitAPatch.
>
> By the way, if you or other of your colleagues is willing to participate
> in net/can and or  hw/net/can patches reviews, I would be happy if you
> join my attempt and we can record that we are available to take care
> abut these in MAINTAINERS file.
Given that I spent good amount of time working with net/can, I am willing to review the patches. Thanks!
>
> Best wishes,
>
> Pavel
>
>

Vikram Garhwal Sept. 3, 2020, 5:29 a.m. UTC | #4

Hi Pavel,
Forgot to add this in last reply: Francisco Iglesias(in cc) was also involved a lot in net/can QEMU devices and willing to help in the review if needed. 

Regards
Vikram

> -----Original Message-----
> From: Vikram Garhwal <[e-mail]>
> Sent: Wednesday, September 2, 2020 10:20 PM
> To: Pavel Pisa <[e-mail]>
> Cc: [e-mail]; Paolo Bonzini <[e-mail]>;
> Stefan Hajnoczi <[e-mail]>; Konrad Frederic
> <[e-mail]>; Deniz Eren <[e-mail]>;
> Oliver Hartkopp <[e-mail]>; Marek Vasut
> <[e-mail]>; Jan Kiszka <[e-mail]>; Oleksij Rempel
> <[e-mail]>; Markus Armbruster <[e-mail]>;
> Ondrej Ille <[e-mail]>; Jan Charvat <[e-mail]>;
> Jiri Novak <[e-mail]>
> Subject: Re: [PATCH v1 1/6] net/can: Initial host SocketCan support for CAN
> FD.
> 
> On Wed, Sep 02, 2020 at 09:51:44AM +0200, Pavel Pisa wrote:
> Hi Pavel,
> > Hello Vikram,
> >
> > thanks much for the patches review.
> >
> > On Tuesday 01 of September 2020 22:01:26 Vikram Garhwal wrote:
> > > Hi Jan,
> > > A couple of comments on this patch.
> > >
> > > On Tue, Jul 14, 2020 at 02:20:14PM +0200, [e-mail]
> wrote:
> > > > From: Jan Charvat <[e-mail]> @@ -185,13 +204,34 @@
> > > > static void can_host_socketcan_connect(CanHostState
> > > > *ch, Error **errp) addr.can_family = AF_CAN;
> > > >      memset(&ifr.ifr_name, 0, sizeof(ifr.ifr_name));
> > > >      strcpy(ifr.ifr_name, c->ifname);
> > > > +    /* check if the frame fits into the CAN netdevice */
> > > >      if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
> > > >          error_setg_errno(errp, errno,
> > > > -                         "SocketCAN host interface %s not available",
> > > > c->ifname); +                         "SocketCAN host interface %s not
> > > > available", +                         c->ifname);
> > >
> > > May be this formatting change in a different patch? As this is not
> > > related to CANFD.
> > > > @@ -232,7 +272,8 @@ static char
> *can_host_socketcan_get_if(Object
> > > > *obj, Error **errp) return g_strdup(c->ifname);  }
> > > >
> > > > -static void can_host_socketcan_set_if(Object *obj, const char
> > > > *value, Error **errp) +static void
> > > > can_host_socketcan_set_if(Object *obj, const char *value,
> > > > +                                      Error **errp)
> > >
> > > This one also not relevant change for CANFD. Rest of the patch looks
> good.
> >
> >
> > I am responsible for mentioned lines change in net/can/can_socketcan.c.
> > When I have reviewed patches after Jan Charvat theses submittion, I
> > have done another bunch of rounds to check that the patches as well as
> > the whole net/can and hw/net/can are checkpatch clean. I am not sure
> > if the incorrect formatting sneaked in in my 2018 submission or
> > patcheck became more strict last years.
> >
> > I can separate these changes changes into separate patch if required.
> May be we can keep them in same patch. I was just referring to "Don't
> include irrelevant changes" section on this page about patches:
> https://wiki.qemu.org/Contribute/SubmitAPatch.
> >
> > By the way, if you or other of your colleagues is willing to
> > participate in net/can and or  hw/net/can patches reviews, I would be
> > happy if you join my attempt and we can record that we are available
> > to take care abut these in MAINTAINERS file.
> Given that I spent good amount of time working with net/can, I am willing
> to review the patches. Thanks!
> >
> > Best wishes,
> >
> > Pavel
> >
> >

Patch

diff --git a/hw/net/can/can_sja1000.c b/hw/net/can/can_sja1000.c
index ea915a023a..d83c550edc 100644
--- a/hw/net/can/can_sja1000.c
+++ b/hw/net/can/can_sja1000.c
@@ -268,6 +268,7 @@  static void buff2frame_pel(const uint8_t *buff, qemu_can_frame *frame)
 {
     uint8_t i;
 
+    frame->flags = 0;
     frame->can_id = 0;
     if (buff[0] & 0x40) { /* RTR */
         frame->can_id = QEMU_CAN_RTR_FLAG;
@@ -303,6 +304,7 @@  static void buff2frame_bas(const uint8_t *buff, qemu_can_frame *frame)
 {
     uint8_t i;
 
+    frame->flags = 0;
     frame->can_id = ((buff[0] << 3) & (0xff << 3)) + ((buff[1] >> 5) & 0x07);
     if (buff[1] & 0x10) { /* RTR */
         frame->can_id = QEMU_CAN_RTR_FLAG;
diff --git a/include/net/can_emu.h b/include/net/can_emu.h
index fce9770928..c6164dcfb4 100644
--- a/include/net/can_emu.h
+++ b/include/net/can_emu.h
@@ -46,7 +46,8 @@  typedef uint32_t qemu_canid_t;
 typedef struct qemu_can_frame {
     qemu_canid_t    can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
     uint8_t         can_dlc; /* data length code: 0 .. 8 */
-    uint8_t         data[8] QEMU_ALIGNED(8);
+    uint8_t         flags;
+    uint8_t         data[64] QEMU_ALIGNED(8);
 } qemu_can_frame;
 
 /* Keep defines for QEMU separate from Linux ones for now */
@@ -58,6 +59,10 @@  typedef struct qemu_can_frame {
 #define QEMU_CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
 #define QEMU_CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
 
+#define QEMU_CAN_FRMF_BRS     0x01 /* bit rate switch (2nd bitrate for data) */
+#define QEMU_CAN_FRMF_ESI     0x02 /* error state ind. of transmitting node */
+#define QEMU_CAN_FRMF_TYPE_FD 0x10 /* internal bit ind. of CAN FD frame */
+
 /**
  * struct qemu_can_filter - CAN ID based filter in can_register().
  * @can_id:   relevant bits of CAN ID which are not masked out.
@@ -97,6 +102,7 @@  struct CanBusClientState {
     char *model;
     char *name;
     void (*destructor)(CanBusClientState *);
+    bool fd_mode;
 };
 
 #define TYPE_CAN_BUS "can-bus"
diff --git a/net/can/can_socketcan.c b/net/can/can_socketcan.c
index b7ef63ec0e..fbc0b62ea4 100644
--- a/net/can/can_socketcan.c
+++ b/net/can/can_socketcan.c
@@ -103,6 +103,14 @@  static void can_host_socketcan_read(void *opaque)
         return;
     }
 
+    if (!ch->bus_client.fd_mode) {
+        c->buf[0].flags = 0;
+    } else {
+        if (c->bufcnt > CAN_MTU) {
+            c->buf[0].flags |= QEMU_CAN_FRMF_TYPE_FD;
+        }
+    }
+
     can_bus_client_send(&ch->bus_client, c->buf, 1);
 
     if (DEBUG_CAN) {
@@ -121,12 +129,21 @@  static ssize_t can_host_socketcan_receive(CanBusClientState *client,
     CanHostState *ch = container_of(client, CanHostState, bus_client);
     CanHostSocketCAN *c = CAN_HOST_SOCKETCAN(ch);
 
-    size_t len = sizeof(qemu_can_frame);
+    size_t len;
     int res;
 
     if (c->fd < 0) {
         return -1;
     }
+    if (frames->flags & QEMU_CAN_FRMF_TYPE_FD) {
+        if (!ch->bus_client.fd_mode) {
+            return 0;
+        }
+        len = CANFD_MTU;
+    } else {
+        len = CAN_MTU;
+
+    }
 
     res = write(c->fd, frames, len);
 
@@ -172,6 +189,8 @@  static void can_host_socketcan_connect(CanHostState *ch, Error **errp)
 {
     CanHostSocketCAN *c = CAN_HOST_SOCKETCAN(ch);
     int s; /* can raw socket */
+    int mtu;
+    int enable_canfd = 1;
     struct sockaddr_can addr;
     struct ifreq ifr;
 
@@ -185,13 +204,34 @@  static void can_host_socketcan_connect(CanHostState *ch, Error **errp)
     addr.can_family = AF_CAN;
     memset(&ifr.ifr_name, 0, sizeof(ifr.ifr_name));
     strcpy(ifr.ifr_name, c->ifname);
+    /* check if the frame fits into the CAN netdevice */
     if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
         error_setg_errno(errp, errno,
-                         "SocketCAN host interface %s not available", c->ifname);
+                         "SocketCAN host interface %s not available",
+                         c->ifname);
         goto fail;
     }
     addr.can_ifindex = ifr.ifr_ifindex;
 
+    if (ioctl(s, SIOCGIFMTU, &ifr) < 0) {
+        error_setg_errno(errp, errno,
+                         "SocketCAN host interface %s SIOCGIFMTU failed",
+                         c->ifname);
+        goto fail;
+    }
+    mtu = ifr.ifr_mtu;
+
+    if (mtu >= CANFD_MTU) {
+        /* interface is ok - try to switch the socket into CAN FD mode */
+        if (setsockopt(s, SOL_CAN_RAW, CAN_RAW_FD_FRAMES,
+                        &enable_canfd, sizeof(enable_canfd))) {
+            warn_report("SocketCAN host interface %s enabling CAN FD failed",
+                        c->ifname);
+        } else {
+            c->parent.bus_client.fd_mode = true;
+        }
+    }
+
     c->err_mask = 0xffffffff; /* Receive error frame. */
     setsockopt(s, SOL_CAN_RAW, CAN_RAW_ERR_FILTER,
                    &c->err_mask, sizeof(c->err_mask));
@@ -232,7 +272,8 @@  static char *can_host_socketcan_get_if(Object *obj, Error **errp)
     return g_strdup(c->ifname);
 }
 
-static void can_host_socketcan_set_if(Object *obj, const char *value, Error **errp)
+static void can_host_socketcan_set_if(Object *obj, const char *value,
+                                      Error **errp)
 {
     CanHostSocketCAN *c = CAN_HOST_SOCKETCAN(obj);
     struct ifreq ifr;