Re: [PATCH 04/13] ppc/pnv: Introduce PnvMachineClass and PnvMachineClass::compat

From: "Cédric Le Goater" <clg@kaod.org>
To: Greg Kurz <groug@kaod.org>, David Gibson <david@gibson.dropbear.id.au>
Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org
Subject: Re: [PATCH 04/13] ppc/pnv: Introduce PnvMachineClass and PnvMachineClass::compat
Date: Fri, 13 Dec 2019 13:44:48 +0100	[thread overview]
Message-ID: <5bf40b1e-48cb-5a20-82b2-7cd037003c27@kaod.org> (raw)
In-Reply-To: <157623839085.360005.4046508784077843216.stgit@bahia.lan>

On 13/12/2019 12:59, Greg Kurz wrote:
> The pnv_dt_create() function generates different contents for the
> "compatible" property of the root node in the DT, depending on the
> CPU type. This is open coded with multiple ifs using pnv_is_powerXX()
> helpers.
> 
> It seems cleaner to achieve with QOM. Introduce a base class for the
> powernv machine and a compat attribute that each child class can use
> to provide the value for the "compatible" property.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>

Reviewed-by: Cédric Le Goater <clg@kaod.org>


> ---
>  hw/ppc/pnv.c         |   33 +++++++++++++++++++--------------
>  include/hw/ppc/pnv.h |   13 +++++++++++++
>  2 files changed, 32 insertions(+), 14 deletions(-)
> 
> diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
> index 0be0b6b411c3..5ac149b149d8 100644
> --- a/hw/ppc/pnv.c
> +++ b/hw/ppc/pnv.c
> @@ -484,9 +484,7 @@ static void pnv_dt_power_mgt(void *fdt)
>  
>  static void *pnv_dt_create(MachineState *machine)
>  {
> -    const char plat_compat8[] = "qemu,powernv8\0qemu,powernv\0ibm,powernv";
> -    const char plat_compat9[] = "qemu,powernv9\0ibm,powernv";
> -    const char plat_compat10[] = "qemu,powernv10\0ibm,powernv";
> +    PnvMachineClass *pmc = PNV_MACHINE_GET_CLASS(machine);
>      PnvMachineState *pnv = PNV_MACHINE(machine);
>      void *fdt;
>      char *buf;
> @@ -504,17 +502,8 @@ static void *pnv_dt_create(MachineState *machine)
>      _FDT((fdt_setprop_cell(fdt, 0, "#size-cells", 0x2)));
>      _FDT((fdt_setprop_string(fdt, 0, "model",
>                               "IBM PowerNV (emulated by qemu)")));
> -    if (pnv_is_power10(pnv)) {
> -        _FDT((fdt_setprop(fdt, 0, "compatible", plat_compat10,
> -                          sizeof(plat_compat10))));
> -    } else if (pnv_is_power9(pnv)) {
> -        _FDT((fdt_setprop(fdt, 0, "compatible", plat_compat9,
> -                          sizeof(plat_compat9))));
> -    } else {
> -        _FDT((fdt_setprop(fdt, 0, "compatible", plat_compat8,
> -                          sizeof(plat_compat8))));
> -    }
> -
> +    _FDT((fdt_setprop(fdt, 0, "compatible", pmc->compat,
> +                      sizeof(pmc->compat))));
>  
>      buf =  qemu_uuid_unparse_strdup(&qemu_uuid);
>      _FDT((fdt_setprop_string(fdt, 0, "vm,uuid", buf)));
> @@ -1692,6 +1681,8 @@ static void pnv_machine_power8_class_init(ObjectClass *oc, void *data)
>  {
>      MachineClass *mc = MACHINE_CLASS(oc);
>      XICSFabricClass *xic = XICS_FABRIC_CLASS(oc);
> +    PnvMachineClass *pmc = PNV_MACHINE_CLASS(oc);
> +    static const char compat[] = "qemu,powernv8\0qemu,powernv\0ibm,powernv";
>  
>      mc->desc = "IBM PowerNV (Non-Virtualized) POWER8";
>      mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power8_v2.0");
> @@ -1699,26 +1690,39 @@ static void pnv_machine_power8_class_init(ObjectClass *oc, void *data)
>      xic->icp_get = pnv_icp_get;
>      xic->ics_get = pnv_ics_get;
>      xic->ics_resend = pnv_ics_resend;
> +
> +    pmc->compat = compat;
> +    pmc->compat_size = sizeof(compat);
>  }
>  
>  static void pnv_machine_power9_class_init(ObjectClass *oc, void *data)
>  {
>      MachineClass *mc = MACHINE_CLASS(oc);
>      XiveFabricClass *xfc = XIVE_FABRIC_CLASS(oc);
> +    PnvMachineClass *pmc = PNV_MACHINE_CLASS(oc);
> +    static const char compat[] = "qemu,powernv9\0ibm,powernv";
>  
>      mc->desc = "IBM PowerNV (Non-Virtualized) POWER9";
>      mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power9_v2.0");
>      xfc->match_nvt = pnv_match_nvt;
>  
>      mc->alias = "powernv";
> +
> +    pmc->compat = compat;
> +    pmc->compat_size = sizeof(compat);
>  }
>  
>  static void pnv_machine_power10_class_init(ObjectClass *oc, void *data)
>  {
>      MachineClass *mc = MACHINE_CLASS(oc);
> +    PnvMachineClass *pmc = PNV_MACHINE_CLASS(oc);
> +    static const char compat[] = "qemu,powernv10\0ibm,powernv";
>  
>      mc->desc = "IBM PowerNV (Non-Virtualized) POWER10";
>      mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power10_v1.0");
> +
> +    pmc->compat = compat;
> +    pmc->compat_size = sizeof(compat);
>  }
>  
>  static void pnv_machine_class_init(ObjectClass *oc, void *data)
> @@ -1796,6 +1800,7 @@ static const TypeInfo types[] = {
>          .instance_size = sizeof(PnvMachineState),
>          .instance_init = pnv_machine_instance_init,
>          .class_init    = pnv_machine_class_init,
> +        .class_size    = sizeof(PnvMachineClass),
>          .interfaces = (InterfaceInfo[]) {
>              { TYPE_INTERRUPT_STATS_PROVIDER },
>              { },
> diff --git a/include/hw/ppc/pnv.h b/include/hw/ppc/pnv.h
> index 92f80b1ccead..d534746bd493 100644
> --- a/include/hw/ppc/pnv.h
> +++ b/include/hw/ppc/pnv.h
> @@ -185,6 +185,19 @@ PowerPCCPU *pnv_chip_find_cpu(PnvChip *chip, uint32_t pir);
>  #define TYPE_PNV_MACHINE       MACHINE_TYPE_NAME("powernv")
>  #define PNV_MACHINE(obj) \
>      OBJECT_CHECK(PnvMachineState, (obj), TYPE_PNV_MACHINE)
> +#define PNV_MACHINE_GET_CLASS(obj) \
> +    OBJECT_GET_CLASS(PnvMachineClass, obj, TYPE_PNV_MACHINE)
> +#define PNV_MACHINE_CLASS(klass) \
> +    OBJECT_CLASS_CHECK(PnvMachineClass, klass, TYPE_PNV_MACHINE)
> +
> +typedef struct PnvMachineClass {
> +    /*< private >*/
> +    MachineClass parent_class;
> +
> +    /*< public >*/
> +    const char *compat;
> +    int compat_size;
> +} PnvMachineClass;
>  
>  typedef struct PnvMachineState {
>      /*< private >*/
>