linux_dsm_epyc7002/drivers/net
John David Anglin 7c0db24cc4 dsa: mv88e6xxx: Ensure all pending interrupts are handled prior to exit
The GPIO interrupt controller on the espressobin board only supports edge interrupts.
If one enables the use of hardware interrupts in the device tree for the 88E6341, it is
possible to miss an edge.  When this happens, the INTn pin on the Marvell switch is
stuck low and no further interrupts occur.

I found after adding debug statements to mv88e6xxx_g1_irq_thread_work() that there is
a race in handling device interrupts (e.g. PHY link interrupts).  Some interrupts are
directly cleared by reading the Global 1 status register.  However, the device interrupt
flag, for example, is not cleared until all the unmasked SERDES and PHY ports are serviced.
This is done by reading the relevant SERDES and PHY status register.

The code only services interrupts whose status bit is set at the time of reading its status
register.  If an interrupt event occurs after its status is read and before all interrupts
are serviced, then this event will not be serviced and the INTn output pin will remain low.

This is not a problem with polling or level interrupts since the handler will be called
again to process the event.  However, it's a big problem when using level interrupts.

The fix presented here is to add a loop around the code servicing switch interrupts.  If
any pending interrupts remain after the current set has been handled, we loop and process
the new set.  If there are no pending interrupts after servicing, we are sure that INTn has
gone high and we will get an edge when a new event occurs.

Tested on espressobin board.

Fixes: dc30c35be7 ("net: dsa: mv88e6xxx: Implement interrupt support.")
Signed-off-by:  John David Anglin <dave.anglin@bell.net>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-13 20:46:38 -08:00
..
appletalk drivers/net: appletalk/cops: remove redundant if statement and mask 2018-12-24 14:48:26 -08:00
arcnet
bonding bonding: update nest level on unlink 2019-01-10 16:49:39 -05:00
caif net: caif: call dev_consume_skb_any when skb xmit done 2019-01-29 10:09:28 -08:00
can can: flexcan: fix NULL pointer exception during bringup 2019-01-22 11:35:33 +01:00
dsa dsa: mv88e6xxx: Ensure all pending interrupts are handled prior to exit 2019-02-13 20:46:38 -08:00
ethernet net/mlx5e: XDP, fix redirect resources availability check 2019-02-13 15:40:51 -08:00
fddi net: defxx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles 2019-02-06 17:38:15 -08:00
fjes fjes: convert to DEFINE_SHOW_ATTRIBUTE 2018-12-10 12:05:20 -08:00
hamradio net/hamradio/6pack: use mod_timer() to rearm timers 2019-01-02 10:27:01 -08:00
hippi
hyperv hv_netvsc: fix typos in code comments 2019-01-23 13:21:34 -05:00
ieee802154 ieee802154: mcr20a: fix indentation, remove tabs 2019-01-31 17:42:05 +01:00
ipvlan ipvlan, l3mdev: fix broken l3s mode wrt local routes 2019-01-30 22:13:34 -08:00
netdevsim drivers: net: netdevsim: use skb_sec_path helper 2018-12-19 11:21:37 -08:00
phy net: phy: fix interrupt handling in non-started states 2019-02-13 20:44:12 -08:00
plip
ppp net: Fix usage of pskb_trim_rcsum 2019-01-18 14:05:14 -08:00
slip
team team: avoid complex list operations in team_nl_cmd_options_set() 2019-02-12 14:19:27 -05:00
usb net: usb: asix: ax88772_bind return error when hw_reset fail 2019-01-24 22:33:11 -08:00
vmxnet3 cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
wan net: fsl_ucc_hdlc: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles 2019-02-06 17:38:15 -08:00
wimax
wireless wireless-drivers fixes for 5.0 2019-02-04 09:12:06 -08:00
xen-netback net: xenbus: convert to DEFINE_SHOW_ATTRIBUTE 2018-12-10 12:05:20 -08:00
dummy.c
eql.c
geneve.c geneve: should not call rt6_lookup() when ipv6 was disabled 2019-02-07 10:48:42 -08:00
gtp.c
ifb.c
Kconfig geneve: change NET_UDP_TUNNEL dependency to select 2019-02-12 12:23:59 -05:00
LICENSE.SRC
loopback.c
macsec.c
macvlan.c macvlan: replace kfree_skb by consume_skb for drop profiles 2019-01-17 22:09:09 -08:00
macvtap.c
Makefile
mdio.c
mii.c
net_failover.c net: core: dev: Add extack argument to dev_open() 2018-12-06 13:26:06 -08:00
netconsole.c
nlmon.c
ntb_netdev.c
rionet.c
sb1000.c
Space.c
sungem_phy.c
tap.c tap: call skb_probe_transport_header after setting skb->dev 2019-01-01 12:01:02 -08:00
thunderbolt.c
tun.c tun: move the call to tun_set_real_num_queues 2019-01-30 21:40:25 -08:00
veth.c
virtio_net.c virtio_net: Account for tx bytes and packets on sending xdp_frames 2019-02-03 20:14:28 -08:00
vrf.c net: core: dev: Add extack argument to dev_change_flags() 2018-12-06 13:26:07 -08:00
vsockmon.c
vxlan.c vxlan: test dev->flags & IFF_UP before calling netif_rx() 2019-02-11 12:39:51 -08:00
xen-netfront.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-12-20 11:53:36 -08:00