linux/arch/um
Johannes Berg 68f5d3f3b6 um: add PCI over virtio emulation driver
To support testing of PCI/PCIe drivers in UML, add a PCI bus
support driver. This driver uses virtio, which in UML is really
just vhost-user, to talk to devices, and adds the devices to
the virtual PCI bus in the system.

Since virtio already allows DMA/bus mastering this really isn't
all that hard, of course we need the logic_iomem infrastructure
that was added by a previous patch.

The protocol to talk to the device is has a few fairly simple
messages for reading to/writing from config and IO spaces, and
messages for the device to send the various interrupts (INT#,
MSI/MSI-X and while suspended PME#).

Note that currently no offical virtio device ID is assigned for
this protocol, as a consequence this patch requires defining it
in the Kconfig, with a default that makes the driver refuse to
work at all.

Finally, in order to add support for MSI/MSI-X interrupts, some
small changes are needed in the UML IRQ code, it needs to have
more interrupts, changing NR_IRQS from 64 to 128 if this driver
is enabled, but not actually use them for anything so that the
generic IRQ domain/MSI infrastructure can allocate IRQ numbers.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-06-17 21:45:43 +02:00
..
configs um: Cleanup CONFIG_IOSCHED_CFQ 2020-03-29 23:15:22 +02:00
drivers um: add PCI over virtio emulation driver 2021-06-17 21:45:43 +02:00
include um: add PCI over virtio emulation driver 2021-06-17 21:45:43 +02:00
kernel um: add PCI over virtio emulation driver 2021-06-17 21:45:43 +02:00
os-Linux um: time-travel/signals: fix ndelay() in interrupt 2021-06-17 21:44:52 +02:00
scripts License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
Kconfig um: add PCI over virtio emulation driver 2021-06-17 21:45:43 +02:00
Kconfig.debug um: Disable CONFIG_GCOV with MODULES 2021-04-15 23:10:33 +02:00
Makefile kbuild: remove cc-option test of -fno-stack-protector 2020-07-07 11:13:10 +09:00
Makefile-os-Linux
Makefile-skas