This series attempts to improve the modelling of legacy x86 PICs within
QEMU. The initial aim was to have a qdev device with one output gpio, and
16 input gpios representing the legacy IRQ lines, however as I went about
trying to model this, I found a number of other inconsistencies/bugs: in
particular there seemed to be some fuzziness around the functionality that
belongs to an individual i8259 chip, and a cascaded i8259 configuration.

For the purposes of this patch an i8259 device is considered to be a single
i8259 chip whilst a PIC device is considered to be either a cascaded i8259
configuration (emulated/KVM) or standalone device (Xen) representing the set
of 16 legacy IRQs and a single output IRQ.

Due to the updated device names, there is currently one visible change in
the HMP monitor output for "info irq" where the isa-i8259 device now appears
as isa-i8259-pic and the kvm-i8259 device appears as kvm-i8259-pic (see
patch 19).

Signed-off-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>

[Patches still requiring review: 5-11, 18-20, 22, 26]


v2:
- Rebase onto master

- Add R-B tags from Peter

- Remove FIXME from commit message and rename trace event in patch 13

- Introduce a separate I8259State for TYPE_I8259 and KVMI8259State for
  TYPE_KVM_I8259 as suggested by Peter

- Keep but rename the associated classes for TYPE_I8259 and TYPE_KVM_I8259
  and move the DeviceRealize function into each one, instead of keeping it
  in the parent class

- Add patches to make variable names consistent when accessing
  I8259CommonState from child objects

- Update the comment on patch 19 to reflect that implementing the
  cascaded secondary is actually a bugfix


Mark Cave-Ayland (27):
  i8259_internal.h: rename PIC_COMMON to I8259_COMMON
  i8259_internal.h: rename TYPE_I8259_COMMON to i8259-common
  i8259_internal.h: rename PICCommonState to I8259CommonState
  i8259_internal.h: rename PICCommonClass to I8259CommonClass
  i8259.c: rename PICClass to I8259Class
  i8259.c: introduce TYPE_I8259 device
  i8259.c: always use cs for I8259CommonState variables
  kvm/i8259.c: rename KVMPICClass to KVMI8259Class
  kvm/i8259.c: introduce TYPE_KVM_I8259 device
  kvm/i8259.c: always use cs for I8259CommonState variables
  i8259_common.c: always use cs for I8259CommonState variables
  i8259_common.c: use i8259/i8259_common prefix for functions
  i8259.c: use i8259 prefix for functions
  kvm/i8259.c: use kvm_i8259 prefix for functions
  i8259_common.c: convert to use DEFINE_TYPES() macro
  i8259.c: convert to use DEFINE_TYPES() macro
  kvm/i8259.c: convert to use DEFINE_TYPES() macro
  i8259.c: introduce TYPE_I8259_PIC device
  i8259.c: properly cascade secondary i8259 from primary i8259
  kvm/i8259.c: introduce TYPE_KVM_I8259_PIC device
  xen-hvm.c: rename xen_interrupt_controller_init() to xen_i8259_init()
  xen/xen-hvm.c: introduce TYPE_XEN_I8259_PIC device
  i8259_common.c: remove unused i8259_init_chip() function
  i8259: move InterruptStatsProviderClass get_statistics() from i8259 to
    PIC
  i8259.c: switch isa_pic from I8259State to I8259PICState
  i8259_common.c: remove static irq_count and irq_level variables
  i8259_common.c: add missing 0x prefixes to "info pic" output

 include/hw/intc/i8259.h         |  11 +-
 include/hw/isa/i8259_internal.h |  19 +-
 include/hw/xen/xen.h            |   2 +-
 hw/i386/kvm/i8259.c             | 250 ++++++++++++-----
 hw/i386/pc.c                    |   2 +-
 hw/i386/xen/xen-hvm.c           |  40 ++-
 hw/intc/i8259.c                 | 465 ++++++++++++++++++++------------
 hw/intc/i8259_common.c          | 225 +++++++---------
 stubs/xen-hw-stub.c             |   2 +-
 hw/intc/trace-events            |   8 +-
 10 files changed, 637 insertions(+), 387 deletions(-)

-- 
2.43.0