Re: [PATCH 0/6] Add Microchip MCP25XXFD CAN driver

From: Marc Kleine-Budde
Date: Thu Jun 11 2020 - 16:30:33 EST


On 6/11/20 6:26 PM, Marc Kleine-Budde wrote:
> I initially started looking at Martin's driver and it was not using several
> modern CAN driver infrastructures. I then posted some cleanup patches but Martin
> was not working on the driver any more. Then I decided to rewrite the driver,
> that is the one I'm hoping to mainline soon.

Seems the driver still suffers from the same problems the last time I looked at it:

I'm on a raspi4 with a mcp2518fd connected to spi0 cs0 and cs1.

Running a canfdtest -vg can0; canfdtest -v can1. It runs into this problem on a
unloaded system and scaling_governor=performance within minutes:

> Jun 11 21:27:08 rpi4 kernel: mcp25xxfd spi0.0 can1: Something is wrong - we got a TEF interrupt but we were not able to detect a finished fifo
> Jun 11 21:27:08 rpi4 kernel: mcp25xxfd spi0.0 can1: Something is wrong - we got a TEF interrupt but we were not able to detect a finished fifo
> Jun 11 21:27:08 rpi4 kernel: mcp25xxfd spi0.0 can1: tefif: fifo 6 not pending - tef data: id: 00000078 flags: 00000c08, ts: 0addbed3 - this may be a problem with spi signal quality- try reducing spi-clock speed if this can get reproduced
> Jun 11 21:27:08 rpi4 kernel: mcp25xxfd spi0.0 can1: tefif: fifo 7 not pending - tef data: id: 00000078 flags: 00000e08, ts: 0addc2e5 - this may be a problem with spi signal quality- try reducing spi-clock speed if this can get reproduced
> Jun 11 21:27:08 rpi4 kernel: mcp25xxfd spi0.0 can1: tefif: fifo 1 not pending - tef data: id: 00000078 flags: 00000208, ts: 0addc701 - this may be a problem with spi signal quality- try reducing spi-clock speed if this can get reproduced
> Jun 11 21:27:08 rpi4 kernel: mcp25xxfd spi0.0 can1: tefif: fifo 2 not pending - tef data: id: 00000078 flags: 00000408, ts: 0addcb1b - this may be a problem with spi signal quality- try reducing spi-clock speed if this can get reproduced

Marc

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