Re: [PATCH] net: usb: lan78xx: Use phy_mac_interrupt() for interrupt handling

From: Daniel Wagner <dwagner@suse.de>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>,
	UNGLinuxDriver@microchip.com, netdev@vger.kernel.org,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-rt-users@vger.kernel.org,
	Woojung Huh <woojung.huh@microchip.com>,
	Marc Zyngier <maz@kernel.org>, Andrew Lunn <andrew@lunn.ch>,
	Stefan Wahren <wahrenst@gmx.net>,
	Jisheng Zhang <Jisheng.Zhang@synaptics.com>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] net: usb: lan78xx: Use phy_mac_interrupt() for interrupt handling
Date: Thu, 24 Oct 2019 13:06:10 +0200	[thread overview]
Message-ID: <20191024110610.lwwy75dkgwjdxml6@beryllium.lan> (raw)
In-Reply-To: <20191024104317.32bp32krrjmfb36p@linutronix.de>

On Thu, Oct 24, 2019 at 12:43:17PM +0200, Sebastian Andrzej Siewior wrote:
> On 2019-10-23 10:06:40 [+0200], Daniel Wagner wrote:
> 
> Since this does not improve the situation as a whole it might be best to
> remove the code as suggested by Daniel.

I have tried to fix the above issue. It looks like the interrupt
handler doesn't work at all. Below is the log with all debug prints
enabled. I just see one PHY interrupt. Don't know if that is okay or
not.

[    3.719647] lan78xx 1-1.1.1:1.0 (unnamed net_device) (uninitialized): deferred multicast write 0x00007ca0
[    3.861125] lan78xx 1-1.1.1:1.0 (unnamed net_device) (uninitialized): No External EEPROM. Setting MAC Speed
[    3.872500] libphy: lan78xx-mdiobus: probed
[    3.883927] lan78xx 1-1.1.1:1.0 (unnamed net_device) (uninitialized): registered mdiobus bus usb-001:004
[    3.893600] lan78xx 1-1.1.1:1.0 (unnamed net_device) (uninitialized): phydev->irq = 79
[    4.274367] random: crng init done
[    4.929478] lan78xx 1-1.1.1:1.0 eth0: receive multicast hash filter
[    4.935922] lan78xx 1-1.1.1:1.0 eth0: deferred multicast write 0x00007ca2
[    6.537962] lan78xx 1-1.1.1:1.0 eth0: PHY INTR: 0x00020000
[    6.549129] lan78xx 1-1.1.1:1.0 eth0: speed: 1000 duplex: 1 anadv: 0x05e1 anlpa: 0xc1e1
[    6.557293] lan78xx 1-1.1.1:1.0 eth0: rx pause disabled, tx pause disabled
[    6.572581] Sending DHCP requests ..., OK
[   12.200693] IP-Config: Got DHCP answer from 192.168.19.2, my address is 192.168.19.53
[   12.208654] IP-Config: Complete:
[   12.211929]      device=eth0, hwaddr=b8:27:eb:85:c7:c9, ipaddr=192.168.19.53, mask=255.255.255.0, gw=192.168.19.1
[   12.222350]      host=192.168.19.53, domain=, nis-domain=(none)
[   12.228364]      bootserver=192.168.19.2, rootserver=192.168.19.2, rootpath=
[   12.228369]      nameserver0=192.168.19.2
[   12.239812] ALSA device list:
[   12.242839]   No soundcards found.
[   12.256896] VFS: Mounted root (nfs filesystem) on device 0:19.
[   12.263501] devtmpfs: mounted
[   12.273037] Freeing unused kernel memory: 5504K
[   12.277769] Run /sbin/init as init process

and after this the NFS timeouts appear. I tried to figure out how the
PHY works [1] and played a bit around with fiddling with a few bits in
the registers. But now success at all.

I agree with Sebastian, with the revert the driver works at least.

Thanks,
Daniel

[1] http://ww1.microchip.com/downloads/en/DeviceDoc/LAN7800-Data-Sheet-DS00001992G.pdf