Re: [Qemu-devel] [PATCH v11 1/5] apic: move APIC's MMIO region mapping into APIC

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 2 Sep 2015 17:36:18 +0800
Zhu Guihua <zhugh.fnst@cn.fujitsu.com> wrote:

> From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
> 
> When ICC bus/bridge is removed, APIC MMIO will be left
> unmapped since it was mapped into system's address space
> indirectly by ICC bridge.
> Fix it by moving mapping into APIC code, so it would be
> possible to remove ICC bus/bridge code later.
> 
> Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
> Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
> ---
>  hw/i386/pc.c          |  7 -------
>  hw/intc/apic_common.c |  6 ------
>  target-i386/cpu.c     | 15 +++++++++++++++
>  3 files changed, 15 insertions(+), 13 deletions(-)
> 
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index b1c96a8..e15971c 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1157,13 +1157,6 @@ void pc_cpus_init(PCMachineState *pcms, DeviceState *icc_bridge)
>          object_unref(OBJECT(cpu));
>      }
>  
> -    /* map APIC MMIO area if CPU has APIC */
> -    if (cpu && cpu->apic_state) {
> -        /* XXX: what if the base changes? */
> -        sysbus_mmio_map_overlap(SYS_BUS_DEVICE(icc_bridge), 0,
> -                                APIC_DEFAULT_ADDRESS, 0x1000);
> -    }
> -
>      /* tell smbios about cpuid version and features */
>      smbios_set_cpuid(cpu->env.cpuid_version, cpu->env.features[FEAT_1_EDX]);
>  }
> diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
> index 0032b97..c0b32eb 100644
> --- a/hw/intc/apic_common.c
> +++ b/hw/intc/apic_common.c
> @@ -296,7 +296,6 @@ static void apic_common_realize(DeviceState *dev, Error **errp)
>      APICCommonClass *info;
>      static DeviceState *vapic;
>      static int apic_no;
> -    static bool mmio_registered;
>  
>      if (apic_no >= MAX_APICS) {
>          error_setg(errp, "%s initialization failed.",
> @@ -307,11 +306,6 @@ static void apic_common_realize(DeviceState *dev, Error **errp)
>  
>      info = APIC_COMMON_GET_CLASS(s);
>      info->realize(dev, errp);
> -    if (!mmio_registered) {
> -        ICCBus *b = ICC_BUS(qdev_get_parent_bus(dev));
> -        memory_region_add_subregion(b->apic_address_space, 0, &s->io_memory);
> -        mmio_registered = true;
> -    }
>  
>      /* Note: We need at least 1M to map the VAPIC option ROM */
>      if (!vapic && s->vapic_control & VAPIC_ENABLE_MASK &&
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index cfb8aa7..66b6b0d 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -2745,6 +2745,7 @@ static void x86_cpu_apic_create(X86CPU *cpu, Error **errp)
>      /* TODO: convert to link<> */
>      apic = APIC_COMMON(cpu->apic_state);
>      apic->cpu = cpu;
> +    apic->apicbase = APIC_DEFAULT_ADDRESS | MSR_IA32_APICBASE_ENABLE;
>  }
>  
>  static void x86_cpu_apic_realize(X86CPU *cpu, Error **errp)
> @@ -2789,8 +2790,10 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
>      X86CPU *cpu = X86_CPU(dev);
>      X86CPUClass *xcc = X86_CPU_GET_CLASS(dev);
>      CPUX86State *env = &cpu->env;

> +    APICCommonState *apic;
this and below hunks break build for *-linux-user targets,
suggest to move it to x86_cpu_apic_realize() which is empty for
user-only and softmmu builds.

>      Error *local_err = NULL;
>      static bool ht_warned;
> +    static bool apic_mmio_map_once;
>  
>      if (cpu->apic_id < 0) {
>          error_setg(errp, "apic-id property was not initialized properly");
> @@ -2877,6 +2880,18 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
>      if (local_err != NULL) {
>          goto out;
>      }
> +
> +    /* Map APIC MMIO area */
> +    apic = APIC_COMMON(cpu->apic_state);
> +    if (!apic_mmio_map_once) {
> +        memory_region_add_subregion_overlap(get_system_memory(),
> +                                            apic->apicbase &
> +                                            MSR_IA32_APICBASE_BASE,
> +                                            &apic->io_memory,
> +                                            0x1000);
> +        apic_mmio_map_once = true;
> +    }
> +
>      cpu_reset(cs);
>  
>      xcc->parent_realize(dev, &local_err);