On Mon, 28 Sep 2020 19:15:24 +0200
Philippe Mathieu-Daudé <f4...@amsat.org> wrote:
> Let CPUState have a clock source (named 'clk') and CPUClass
> have a clock_update() callback. The clock can be optionally
> set Using qdev_connect_clock_in() from the Clock API.
> If the clock changes, the optional clock_update() will be
> called.
the sole user of it is mips cpu, so question is why
you are making it part of generic CPUm instead of
MIPSCPUClass/MIPSCPU?
>
> Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> ---
> include/hw/core/cpu.h | 5 +++++
> hw/core/cpu.c | 12 ++++++++++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
> index 6c34798c8b3..6989d90c193 100644
> --- a/include/hw/core/cpu.h
> +++ b/include/hw/core/cpu.h
> @@ -31,6 +31,7 @@
> #include "qemu/thread.h"
> #include "qemu/plugin.h"
> #include "qom/object.h"
> +#include "hw/clock.h"
>
> typedef int (*WriteCoreDumpFunction)(const void *buf, size_t size,
> void *opaque);
> @@ -155,6 +156,7 @@ struct TranslationBlock;
> * @disas_set_info: Setup architecture specific components of disassembly
> info
> * @adjust_watchpoint_address: Perform a target-specific adjustment to an
> * address before attempting to match it against watchpoints.
> + * @clock_update: Callback for input clock changes
> *
> * Represents a CPU family or model.
> */
> @@ -176,6 +178,7 @@ struct CPUClass {
> unsigned size, MMUAccessType access_type,
> int mmu_idx, MemTxAttrs attrs,
> MemTxResult response, uintptr_t retaddr);
> + void (*clock_update)(CPUState *cpu);
> bool (*virtio_is_big_endian)(CPUState *cpu);
> int (*memory_rw_debug)(CPUState *cpu, vaddr addr,
> uint8_t *buf, int len, bool is_write);
> @@ -316,6 +319,7 @@ struct qemu_work_item;
> * QOM parent.
> * @nr_cores: Number of cores within this CPU package.
> * @nr_threads: Number of threads within this CPU.
> + * @clock: this CPU source clock (an output clock of another device)
> * @running: #true if CPU is currently running (lockless).
> * @has_waiter: #true if a CPU is currently waiting for the cpu_exec_end;
> * valid under cpu_list_lock.
> @@ -400,6 +404,7 @@ struct CPUState {
> int num_ases;
> AddressSpace *as;
> MemoryRegion *memory;
> + Clock *clock;
>
> void *env_ptr; /* CPUArchState */
> IcountDecr *icount_decr_ptr;
> diff --git a/hw/core/cpu.c b/hw/core/cpu.c
> index c55c09f734c..37fcff3ec64 100644
> --- a/hw/core/cpu.c
> +++ b/hw/core/cpu.c
> @@ -30,6 +30,7 @@
> #include "qemu/qemu-print.h"
> #include "sysemu/tcg.h"
> #include "hw/boards.h"
> +#include "hw/qdev-clock.h"
> #include "hw/qdev-properties.h"
> #include "trace/trace-root.h"
> #include "qemu/plugin.h"
> @@ -247,6 +248,16 @@ void cpu_reset(CPUState *cpu)
> trace_guest_cpu_reset(cpu);
> }
>
> +static void cpu_clk_update(void *opaque)
> +{
> + CPUState *cpu = opaque;
> + CPUClass *cc = CPU_GET_CLASS(cpu);
> +
> + if (cc->clock_update) {
> + cc->clock_update(cpu);
> + }
> +}
> +
> static void cpu_common_reset(DeviceState *dev)
> {
> CPUState *cpu = CPU(dev);
> @@ -367,6 +378,7 @@ static void cpu_common_initfn(Object *obj)
> /* the default value is changed by qemu_init_vcpu() for softmmu */
> cpu->nr_cores = 1;
> cpu->nr_threads = 1;
> + cpu->clock = qdev_init_clock_in(DEVICE(obj), "clk", cpu_clk_update, cpu);
>
> qemu_mutex_init(&cpu->work_mutex);
> QSIMPLEQ_INIT(&cpu->work_list);
