linux/arch/alpha
Lorenzo Pieralisi 86be89939d alpha/PCI: Fix noname IRQ level detection
The conversion of the alpha architecture PCI host bridge legacy IRQ
mapping/swizzling to the new PCI host bridge map/swizzle hooks carried
out through:

commit 0e4c2eeb75 ("alpha/PCI: Replace pci_fixup_irqs() call with
host bridge IRQ mapping hooks")

implies that IRQ for devices are now allocated through pci_assign_irq()
function in pci_device_probe() that is called when a driver matching a
device is found in order to probe the device through the device driver.

Alpha noname platforms required IRQ level programming to be executed
in sio_fixup_irq_levels(), that is called in noname_init_pci(), a
platform hook called within a subsys_initcall.

In noname_init_pci(), present IRQs are detected through
sio_collect_irq_levels() that check the struct pci_dev->irq number
to detect if an IRQ has been allocated for the device.

By the time sio_collect_irq_levels() is called, some devices may still
have not a matching driver loaded to match them (eg loadable module)
therefore their IRQ allocation is still pending - which means that
sio_collect_irq_levels() does not programme the correct IRQ level for
those devices, causing their IRQ handling to be broken when the device
driver is actually loaded and the device is probed.

Fix the issue by adding code in the noname map_irq() function
(noname_map_irq()) that, whilst mapping/swizzling the IRQ line, it also
ensures that the correct IRQ level programming is executed at platform
level, fixing the issue.

Fixes: 0e4c2eeb75 ("alpha/PCI: Replace pci_fixup_irqs() call with
host bridge IRQ mapping hooks")
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org # 4.14
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Meelis Roos <mroos@linux.ee>
Signed-off-by: Matt Turner <mattst88@gmail.com>
2018-01-20 16:22:36 -08:00
..
boot License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
include bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
kernel alpha/PCI: Fix noname IRQ level detection 2018-01-20 16:22:36 -08:00
lib alpha: extend memset16 to EV6 optimised routines 2018-01-16 19:34:46 -08:00
math-emu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
oprofile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig Merge branch 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2017-11-15 10:14:11 -08:00
Kconfig.debug License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile alpha: makefile: don't enforce small data model for kernel builds 2013-04-07 12:59:30 -07:00
defconfig alpha: defconfig: Cleanup from old Kconfig options 2017-09-04 12:04:33 -07:00