Features/QOM/CPU

QOM CPU

Convert CPUState to QOM.

Motivation

1. Short-term: Allow inspecting and modifying CPU properties via QOM.
2. Short-term: Avoid common target code doing ifs or switches on CPU identifiers.
   • target-arm/helper.c: cpu_reset_model_id()
3. Short-term: Replace CPU_COMMON macro and duplicated reset code by inheritance.
4. Mid-term: Avoid dependency of common code on #defines from cpu.h.
5. Mid-term: Ease instantiation of mixed software-visible cores within one target, e.g.
   • NXP LPC43xx: Cortex-M4 + Cortex-M0
   • ARM big.LITTLE: Cortex-A15 + Cortex-A7
   • Freescale Vybrid VF6xx/VFP7xx: Cortex-A5 + Cortex-M4
6. Long-term: Work towards allowing to compile multiple targets into one executable.
   • Renesas R-Car H1, M1A: ARM Cortex-A9 + SH-4A
   • Renesas R-Home S1: ARM Cortex-A9 + SH-4A + ARM7TDMI-S

"CPU" name conflict

Identifier	current	interim	final
struct CPU$archState or struct CPUState_$arch	defined in target-*/cpu.h		???
#define CPUState	alias to CPU$archState / CPUState_$arch		dropped in favor of CPU
struct CPUClass		class
#define CPU_CLASS(class)		cast macro for class
struct CPU		object
#define CPU(obj)		cast macro for object
#define CPU_GET_CLASS(obj)		macro to obtain class pointer

Resolved by renaming existing CPUState to CPUArchState and by using struct CPUState for the object state, while using CPU(obj) as macro for casting.

Status

NB: Due to hosting issues, branches have moved to GitHub.

name	depends on
type_init()
qom-user	type_init()
object_class_get_list()
qom-cpu	qom-user
qom-cpu-arm	qom-cpu
qom-cpu-unicore32	qom-cpu
qom-cpu-s390	qom-cpu
qom-cpu-x86, part 1	qom-cpu
qom-cpu-sparc	qom-cpu
qom-cpu-ppc	qom-cpu
qom-cpu-alpha	qom-cpu
qom-cpu-sh4 (to be updated)	qom-cpu, object_realize()
qom-cpu-others (to be split up)	qom-cpu