Hi Marc,
Thanks for the feedback.
> Subject: Re: [PATCH 3/6] can: sja1000: Add Quirks for RZ/N1 SJA1000 CAN
> controller
>
> On 02.07.2022 15:01:27, Biju Das wrote:
> > Chapter 6.5.16 of the RZ/N1 Peripheral Manual mentions the below
> > differences compared to the reference Philips SJA1000 device.
> >
> > Handling of Transmitted Messages:
> > * The CAN controller does not copy transmitted messages to the
> receive
> > buffer, unlike the reference device.
>
> This is something different than....
>
> > int register_sja1000dev(struct net_device *dev) {
> > + struct sja1000_priv *priv = netdev_priv(dev);
> > int ret;
> >
> > if (!sja1000_probe_chip(dev))
> > return -ENODEV;
> >
> > - dev->flags |= IFF_ECHO; /* we support local echo */
> > + if (!(priv->flags & SJA1000_NO_HW_LOOPBACK_QUIRK))
> > + dev->flags |= IFF_ECHO; /* we support local echo */
>
> ... the IFF_ECHO.
>
> IFF_ECHO set means the driver cals can_put_echo_skb() before TX and
> can_get_echo_skb() after TX complete interrupt.
OK.
>
> | irqreturn_t sja1000_interrupt(int irq, void *dev_id)
> [...]
> | while ((isrc = priv->read_reg(priv, SJA1000_IR)) &&
> | (n < SJA1000_MAX_IRQ)) {
> |
> | status = priv->read_reg(priv, SJA1000_SR);
> | /* check for absent controller due to hw unplug */
> | if (status == 0xFF && sja1000_is_absent(priv))
> | goto out;
> |
> | if (isrc & IRQ_WUI)
> | netdev_warn(dev, "wakeup interrupt\n");
> |
> | if (isrc & IRQ_TI) {
> | /* transmission buffer released */
> | if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
> | !(status & SR_TCS)) {
> | stats->tx_errors++;
> | can_free_echo_skb(dev, 0, NULL);
> | } else {
>
> Please add a netdev_info() for debugging and verify that you get a TX
> complete IRQ.
I have put prints and I confirm I get Tx complete IRQ.
--- a/drivers/net/can/sja1000/sja1000.c
+++ b/drivers/net/can/sja1000/sja1000.c
@@ -526,6 +526,7 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
stats->tx_errors++;
can_free_echo_skb(dev, 0, NULL);
} else {
+ netdev_info(dev,"#### Completed message in IRQ");
/* transmission complete */
root@rzn1d400-db:/rzn1_tests/linux# ./test-can.sh
Testing sending from can0 to can1 at 100000 bps
[ 30.032757] sja1000_platform 52105000.can can1: setting BTR0=0x0e BTR1=0x1c
[ 30.062123] IPv6: ADDRCONF(NETDEV_CHANGE): can1: link becomes ready
[ 30.128729] sja1000_platform 52104000.can can0: setting BTR0=0x0e BTR1=0x1c
[ 31.130232] IPv6: ADDRCONF(NETDEV_CHANGE): can0: link becomes ready
[ 32.237998] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 32.246774] sja1000_platform 52104000.can can0: #### Completed message in IRQ
....
.....
[ 33.210809] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 33.221272] sja1000_platform 52104000.can can0: #### Completed message in IRQ
Testing sending from can0 to can1 at 500000 bps
[ 33.366862] sja1000_platform 52105000.can can1: setting BTR0=0x02 BTR1=0x1c
[ 33.455829] sja1000_platform 52104000.can can0: setting BTR0=0x02 BTR1=0x1c
[ 35.546544] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 35.554487] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 35.562322] sja1000_platform 52104000.can can0: #### Completed message in IRQ
.....
[ 36.520433] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 36.530376] sja1000_platform 52104000.can can0: #### Completed message in IRQ
Testing sending from can0 to can1 at 1000000 bps
[ 36.667887] sja1000_platform 52105000.can can1: setting BTR0=0x01 BTR1=0x27
[ 36.759561] sja1000_platform 52104000.can can0: setting BTR0=0x01 BTR1=0x27
[ 38.849459] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 38.857118] sja1000_platform 52104000.can can0: #### Completed message in IRQ
[ 38.864611] sja1000_platform 52104000.can can0: #### Completed message in IRQ
....
[ 39.830284] sja1000_platform 52104000.can can0: #### Completed message in IRQ
root@rzn1d400-db:/rzn1_tests/linux# cat /proc/interrupts | grep can
35: 300 0 GIC-0 127 Level can0
36: 300 0 GIC-0 128 Level can1
root@rzn1d400-db:/rzn1_tests/linux# ./test-can.sh can1 can0
Testing sending from can1 to can0 at 100000 bps
[ 111.972815] sja1000_platform 52104000.can can0: setting BTR0=0x0e BTR1=0x1c
[ 112.064622] sja1000_platform 52105000.can can1: setting BTR0=0x0e BTR1=0x1c
[ 114.159798] sja1000_platform 52105000.can can1: #### Completed message in IRQ
[ 114.168361] sja1000_platform 52105000.can can1: #### Completed message in IRQ
.....
[ 115.141437] sja1000_platform 52105000.can can1: #### Completed message in IRQ
Testing sending from can1 to can0 at 500000 bps
[ 115.272323] sja1000_platform 52104000.can can0: setting BTR0=0x02 BTR1=0x1c
[ 115.365008] sja1000_platform 52105000.can can1: setting BTR0=0x02 BTR1=0x1c
[ 117.445187] sja1000_platform 52105000.can can1: #### Completed message in IRQ
[ 117.460489] sja1000_platform 52105000.can can1: #### Completed message in IRQ
[ 117.470574] sja1000_platform 52105000.can can1: #### Completed message in IRQ
....
[ 118.430442] sja1000_platform 52105000.can can1: #### Completed message in IRQ
[ 118.440381] sja1000_platform 52105000.can can1: #### Completed message in IRQ
Testing sending from can1 to can0 at 1000000 bps
[ 118.564981] sja1000_platform 52104000.can can0: setting BTR0=0x01 BTR1=0x27
[ 118.655100] sja1000_platform 52105000.can can1: setting BTR0=0x01 BTR1=0x27
[ 120.731882] sja1000_platform 52105000.can can1: #### Completed message in IRQ
[ 120.740605] sja1000_platform 52105000.can can1: #### Completed message in IRQ
...
[ 121.710274] sja1000_platform 52105000.can can1: #### Completed message in IRQ
[ 121.720370] sja1000_platform 52105000.can can1: #### Completed message in IRQ
root@rzn1d400-db:/rzn1_tests/linux#root@rzn1d400-db:/rzn1_tests/linux# cat /proc/interrupts | grep can
35: 600 0 GIC-0 127 Level can0
36: 600 0 GIC-0 128 Level can1
>
> | /* transmission complete */
> | stats->tx_bytes += can_get_echo_skb(dev, 0,
> NULL);
> | stats->tx_packets++;
> | }
> | netif_wake_queue(dev);
> | }
>
>
> If your hardware doesn't support hardware loopback (configured via
> CMD_SRR):
But our HW supports, CMD_SRR.
b4 bCan_SRR Self Reception Request
1: Set when a message is to be transmitted and received simultaneously
[Condition of “Cleared to 0”]
● Software Reset (Set “1” in bCan_RM)
● Switch to “Bus Off” (Set “1” in bCan_BS)
Cheers,
Biju
>
> | if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
> | cmd_reg_val |= CMD_SRR;
> | else
> | cmd_reg_val |= CMD_TR;
>
> then don't set CAN_CTRLMODE_LOOPBACK in priv->can.ctrlmode_supported.
