Re: [Qemu-devel] [PATCH v3 16/19] hw: acpi: Retrieve the PCI bus from AcpiPciHpState

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 29/10/18 18:01, Samuel Ortiz wrote:
> From: Sebastien Boeuf <sebastien.boeuf@intel.com>
> 
> Instead of using the machine type specific method find_i440fx() to
> retrieve the PCI bus, this commit aims to rely on the fact that the
> PCI bus is known by the structure AcpiPciHpState.
> 
> When the structure is initialized through acpi_pcihp_init() call,
> it saves the PCI bus, which means there is no need to invoke a
> special function later on.
> 
> Based on the fact that find_i440fx() was only used there, this
> patch also removes the function find_i440fx() itself from the
> entire codebase.

Nice :)

> 
> Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
> Signed-off-by: Jing Liu <jing2.liu@linux.intel.com>

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> ---
>   hw/acpi/pcihp.c       | 10 ++++------
>   hw/pci-host/piix.c    |  8 --------
>   include/hw/i386/pc.h  |  1 -
>   stubs/Makefile.objs   |  1 -
>   stubs/pci-host-piix.c |  6 ------
>   5 files changed, 4 insertions(+), 22 deletions(-)
>   delete mode 100644 stubs/pci-host-piix.c
> 
> diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> index 80d42e12ff..254b2e50ab 100644
> --- a/hw/acpi/pcihp.c
> +++ b/hw/acpi/pcihp.c
> @@ -93,10 +93,9 @@ static void *acpi_set_bsel(PCIBus *bus, void *opaque)
>       return bsel_alloc;
>   }
>   
> -static void acpi_set_pci_info(void)
> +static void acpi_set_pci_info(AcpiPciHpState *s)
>   {
>       static bool bsel_is_set;
> -    PCIBus *bus;
>       unsigned bsel_alloc = ACPI_PCIHP_BSEL_DEFAULT;
>   
>       if (bsel_is_set) {
> @@ -104,10 +103,9 @@ static void acpi_set_pci_info(void)
>       }
>       bsel_is_set = true;
>   
> -    bus = find_i440fx(); /* TODO: Q35 support */
> -    if (bus) {
> +    if (s->root) {
>           /* Scan all PCI buses. Set property to enable acpi based hotplug. */
> -        pci_for_each_bus_depth_first(bus, acpi_set_bsel, NULL, &bsel_alloc);
> +        pci_for_each_bus_depth_first(s->root, acpi_set_bsel, NULL, &bsel_alloc);
>       }
>   }
>   
> @@ -213,7 +211,7 @@ static void acpi_pcihp_update(AcpiPciHpState *s)
>   
>   void acpi_pcihp_reset(AcpiPciHpState *s)
>   {
> -    acpi_set_pci_info();
> +    acpi_set_pci_info(s);
>       acpi_pcihp_update(s);
>   }
>   
> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
> index da73743fa2..4940f59c9b 100644
> --- a/hw/pci-host/piix.c
> +++ b/hw/pci-host/piix.c
> @@ -445,14 +445,6 @@ PCIBus *i440fx_init(const char *host_type, const char *pci_type,
>       return b;
>   }
>   
> -PCIBus *find_i440fx(void)
> -{
> -    PCIHostState *s = OBJECT_CHECK(PCIHostState,
> -                                   object_resolve_path("/machine/i440fx", NULL),
> -                                   TYPE_PCI_HOST_BRIDGE);
> -    return s ? s->bus : NULL;
> -}
> -
>   /* PIIX3 PCI to ISA bridge */
>   static void piix3_set_irq_pic(PIIX3State *piix3, int pic_irq)
>   {
> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> index 7d177cd207..f6b2649cf8 100644
> --- a/include/hw/i386/pc.h
> +++ b/include/hw/i386/pc.h
> @@ -260,7 +260,6 @@ PCIBus *i440fx_init(const char *host_type, const char *pci_type,
>                       MemoryRegion *pci_memory,
>                       MemoryRegion *ram_memory);
>   
> -PCIBus *find_i440fx(void);
>   /* piix4.c */
>   extern PCIDevice *piix4_dev;
>   int piix4_init(PCIBus *bus, ISABus **isa_bus, int devfn);
> diff --git a/stubs/Makefile.objs b/stubs/Makefile.objs
> index 5dd0aeeec6..725f78bedc 100644
> --- a/stubs/Makefile.objs
> +++ b/stubs/Makefile.objs
> @@ -41,6 +41,5 @@ stub-obj-y += pc_madt_cpu_entry.o
>   stub-obj-y += vmgenid.o
>   stub-obj-y += xen-common.o
>   stub-obj-y += xen-hvm.o
> -stub-obj-y += pci-host-piix.o
>   stub-obj-y += ram-block.o
>   stub-obj-y += ramfb.o
> diff --git a/stubs/pci-host-piix.c b/stubs/pci-host-piix.c
> deleted file mode 100644
> index 6ed81b1f21..0000000000
> --- a/stubs/pci-host-piix.c
> +++ /dev/null
> @@ -1,6 +0,0 @@
> -#include "qemu/osdep.h"
> -#include "hw/i386/pc.h"
> -PCIBus *find_i440fx(void)
> -{
> -    return NULL;
> -}
>