From: Akshay Bhat <akshay.bhat-jEh4hwF5bVhBDgjK7y7TUQ@public.gmane.org> To: Wolfgang Grandegger <wg-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org>, Akshay Bhat <nodeax-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Cc: mkl-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, linux-can-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Subject: Re: [PATCH v2 2/2] can: spi: hi311x: Add Holt HI-311x CAN driver Date: Fri, 17 Mar 2017 14:28:42 -0400 [thread overview] Message-ID: <ff5d44d1-3bfe-8dae-2aaa-561ab0cb989c@timesys.com> (raw) In-Reply-To: <7730cff6-6e85-c98d-0315-bd3888d3aeb1-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> Hi Wolfgang, On 03/17/2017 01:04 PM, Wolfgang Grandegger wrote: > > Hm, that's unusual. Cable disconnected and then send a message: > > $ grep /proc/interrupts; sleep 10; /proc/interrupts > > should make things clear. But maybe it's a clever chip and it does stop > sending error messages if the error counter does not change any more. > After bus-off, the chip is quiet, of course. Should have a closer look > to the CAN standard. > The interrupt count does not increment after device reaches tx-error-passive (with cable disconnected). # while true; do grep -i hi3110 /proc/interrupts; sleep 10; done & [1] 793 # 111: 0 0 gpio-mxc 12 Edge hi3110 # candump -t d -e any,0:0,#FFFFFFF & [2] 798 # cansend can0 123# # (000.000000) can0 20000004 [8] 00 08 00 00 00 00 60 00 ERRORFRAME controller-problem{tx-error-warning} error-counter-tx-rx{{96}{0}} (000.002122) can0 20000004 [8] 00 20 00 00 00 00 80 00 ERRORFRAME controller-problem{tx-error-passive} error-counter-tx-rx{{128}{0}} 111: 10 0 gpio-mxc 12 Edge hi3110 111: 10 0 gpio-mxc 12 Edge hi3110 111: 10 0 gpio-mxc 12 Edge hi3110 >>> So far using NAPI was mandatory. There is the problem of out-of-order >>> message reception if handled in the isr on multi processor systems. >>> Marc, what is the current policy? >>> >> >> Since this is a SPI based CAN, I am wary for any additional latencies >> NAPI might introduce. The RX handling is being done at the very >> beginning of the ISR for this reason. >> >> Can we go ahead with the existing implementation and re-visit this at a >> later time? > > Likely yes, as Marc has already reviewed the driver once. > Thanks, I will go ahead and submit v4 patch. > BTW: what system board/processor are you using? > It is a custom board using Phytec phyFLEX-i.MX6 Dual SOM. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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From: Akshay Bhat <akshay.bhat@timesys.com> To: Wolfgang Grandegger <wg@grandegger.com>, Akshay Bhat <nodeax@gmail.com> Cc: mkl@pengutronix.de, linux-can@vger.kernel.org, netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] can: spi: hi311x: Add Holt HI-311x CAN driver Date: Fri, 17 Mar 2017 14:28:42 -0400 [thread overview] Message-ID: <ff5d44d1-3bfe-8dae-2aaa-561ab0cb989c@timesys.com> (raw) In-Reply-To: <7730cff6-6e85-c98d-0315-bd3888d3aeb1@grandegger.com> Hi Wolfgang, On 03/17/2017 01:04 PM, Wolfgang Grandegger wrote: > > Hm, that's unusual. Cable disconnected and then send a message: > > $ grep /proc/interrupts; sleep 10; /proc/interrupts > > should make things clear. But maybe it's a clever chip and it does stop > sending error messages if the error counter does not change any more. > After bus-off, the chip is quiet, of course. Should have a closer look > to the CAN standard. > The interrupt count does not increment after device reaches tx-error-passive (with cable disconnected). # while true; do grep -i hi3110 /proc/interrupts; sleep 10; done & [1] 793 # 111: 0 0 gpio-mxc 12 Edge hi3110 # candump -t d -e any,0:0,#FFFFFFF & [2] 798 # cansend can0 123# # (000.000000) can0 20000004 [8] 00 08 00 00 00 00 60 00 ERRORFRAME controller-problem{tx-error-warning} error-counter-tx-rx{{96}{0}} (000.002122) can0 20000004 [8] 00 20 00 00 00 00 80 00 ERRORFRAME controller-problem{tx-error-passive} error-counter-tx-rx{{128}{0}} 111: 10 0 gpio-mxc 12 Edge hi3110 111: 10 0 gpio-mxc 12 Edge hi3110 111: 10 0 gpio-mxc 12 Edge hi3110 >>> So far using NAPI was mandatory. There is the problem of out-of-order >>> message reception if handled in the isr on multi processor systems. >>> Marc, what is the current policy? >>> >> >> Since this is a SPI based CAN, I am wary for any additional latencies >> NAPI might introduce. The RX handling is being done at the very >> beginning of the ISR for this reason. >> >> Can we go ahead with the existing implementation and re-visit this at a >> later time? > > Likely yes, as Marc has already reviewed the driver once. > Thanks, I will go ahead and submit v4 patch. > BTW: what system board/processor are you using? > It is a custom board using Phytec phyFLEX-i.MX6 Dual SOM.
next prev parent reply other threads:[~2017-03-17 18:28 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-01-17 19:22 [PATCH v2 1/2] can: holt_hi311x: document device tree bindings Akshay Bhat 2017-01-17 19:22 ` [PATCH v2 2/2] can: spi: hi311x: Add Holt HI-311x CAN driver Akshay Bhat 2017-03-07 15:31 ` Akshay Bhat 2017-03-09 9:59 ` Wolfgang Grandegger [not found] ` <6df4a9ae-eaba-6f3f-9c23-ae269548b005-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> 2017-03-09 12:34 ` Akshay Bhat 2017-03-09 12:34 ` Akshay Bhat 2017-03-09 14:45 ` Wolfgang Grandegger 2017-03-09 15:28 ` Akshay Bhat 2017-03-09 17:36 ` Wolfgang Grandegger [not found] ` <234d9e75-0083-b8b4-c781-add653fdb550-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> 2017-03-13 15:38 ` Akshay Bhat 2017-03-13 15:38 ` Akshay Bhat [not found] ` <b3ebb569-b50c-39ad-dec5-0059fbfba8fb-jEh4hwF5bVhBDgjK7y7TUQ@public.gmane.org> 2017-03-14 12:11 ` Wolfgang Grandegger 2017-03-14 12:11 ` Wolfgang Grandegger 2017-03-14 16:20 ` Akshay Bhat 2017-03-14 18:08 ` Wolfgang Grandegger 2017-03-14 21:23 ` Wolfgang Grandegger [not found] ` <41439729-42d0-d883-2801-2d3607f2aeab-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> 2017-03-15 4:44 ` Akshay Bhat 2017-03-15 4:44 ` Akshay Bhat 2017-03-15 7:19 ` Wolfgang Grandegger 2017-03-15 9:42 ` Wolfgang Grandegger [not found] ` <3dba0948-ffcb-8e80-fb32-62bb0aca6627-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> 2017-03-16 17:06 ` Akshay Bhat 2017-03-16 17:06 ` Akshay Bhat 2017-03-16 20:02 ` Wolfgang Grandegger 2017-03-16 22:29 ` Akshay Bhat 2017-03-17 7:39 ` Wolfgang Grandegger 2017-03-17 8:17 ` Wolfgang Grandegger 2017-03-17 16:00 ` Akshay Bhat 2017-03-17 17:04 ` Wolfgang Grandegger [not found] ` <7730cff6-6e85-c98d-0315-bd3888d3aeb1-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> 2017-03-17 18:28 ` Akshay Bhat [this message] 2017-03-17 18:28 ` Akshay Bhat [not found] ` <ff5d44d1-3bfe-8dae-2aaa-561ab0cb989c-jEh4hwF5bVhBDgjK7y7TUQ@public.gmane.org> 2017-03-18 12:30 ` Wolfgang Grandegger 2017-03-18 12:30 ` Wolfgang Grandegger
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