[QEMU-PPC,V3,3/6] target/ppc/spapr_caps: Add new tristate cap safe_cache

Add new tristate cap cap-cfpc to represent the cache flush on privilege
change capability.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
---
 hw/ppc/spapr.c         |  2 ++
 hw/ppc/spapr_caps.c    | 40 ++++++++++++++++++++++++++++++++++++++++
 include/hw/ppc/spapr.h |  5 ++++-
 3 files changed, 46 insertions(+), 1 deletion(-)

On Mon, Jan 15, 2018 at 05:32:32PM +1100, Suraj Jitindar Singh wrote:
> Add new tristate cap cap-cfpc to represent the cache flush on privilege
> change capability.
> 
> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  hw/ppc/spapr.c         |  2 ++
>  hw/ppc/spapr_caps.c    | 40 ++++++++++++++++++++++++++++++++++++++++
>  include/hw/ppc/spapr.h |  5 ++++-
>  3 files changed, 46 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index 3e528fe91e..5d62dc9968 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -1791,6 +1791,7 @@ static const VMStateDescription vmstate_spapr = {
>          &vmstate_spapr_cap_htm,
>          &vmstate_spapr_cap_vsx,
>          &vmstate_spapr_cap_dfp,
> +        &vmstate_spapr_cap_cfpc,
>          NULL
>      }
>  };
> @@ -3863,6 +3864,7 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
>      smc->default_caps.caps[SPAPR_CAP_HTM] = SPAPR_CAP_OFF;
>      smc->default_caps.caps[SPAPR_CAP_VSX] = SPAPR_CAP_ON;
>      smc->default_caps.caps[SPAPR_CAP_DFP] = SPAPR_CAP_ON;
> +    smc->default_caps.caps[SPAPR_CAP_CFPC] = SPAPR_CAP_BROKEN;
>      spapr_caps_add_properties(smc, &error_abort);
>  }
>  
> diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c
> index 436250d77b..bc2b2c3590 100644
> --- a/hw/ppc/spapr_caps.c
> +++ b/hw/ppc/spapr_caps.c
> @@ -180,6 +180,18 @@ static void cap_dfp_apply(sPAPRMachineState *spapr, uint8_t val, Error **errp)
>      }
>  }
>  
> +static void cap_safe_cache_apply(sPAPRMachineState *spapr, uint8_t val,
> +                                 Error **errp)
> +{
> +    if (tcg_enabled() && val) {
> +        /* TODO - for now only allow broken for TCG */
> +        error_setg(errp, "Requested safe cache capability level not supported by tcg, try a different value for cap-cfpc");
> +    } else if (kvm_enabled() && (val > kvmppc_get_cap_safe_cache())) {
> +        error_setg(errp, "Requested safe cache capability level not supported by kvm, try a different value for cap-cfpc");
> +    }
> +}
> +
> +#define VALUE_DESC_TRISTATE     " (broken, workaround, fixed)"
>  
>  sPAPRCapabilityInfo capability_table[SPAPR_CAP_NUM] = {
>      [SPAPR_CAP_HTM] = {
> @@ -209,6 +221,15 @@ sPAPRCapabilityInfo capability_table[SPAPR_CAP_NUM] = {
>          .type = "bool",
>          .apply = cap_dfp_apply,
>      },
> +    [SPAPR_CAP_CFPC] = {
> +        .name = "cfpc",
> +        .description = "Cache Flush on Privilege Change" VALUE_DESC_TRISTATE,
> +        .index = SPAPR_CAP_CFPC,
> +        .get = spapr_cap_get_tristate,
> +        .set = spapr_cap_set_tristate,
> +        .type = "string",
> +        .apply = cap_safe_cache_apply,
> +    },
>  };
>  
>  static sPAPRCapabilities default_caps_with_cpu(sPAPRMachineState *spapr,
> @@ -345,6 +366,25 @@ const VMStateDescription vmstate_spapr_cap_dfp = {
>      },
>  };
>  
> +static bool spapr_cap_cfpc_needed(void *opaque)
> +{
> +    sPAPRMachineState *spapr = opaque;
> +
> +    return spapr->cmd_line_caps[SPAPR_CAP_CFPC] &&
> +           (spapr->eff.caps[SPAPR_CAP_CFPC] != spapr->def.caps[SPAPR_CAP_CFPC]);
> +}
> +
> +const VMStateDescription vmstate_spapr_cap_cfpc = {
> +    .name = "spapr/cap/cfpc",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .needed = spapr_cap_cfpc_needed,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT8(mig.caps[SPAPR_CAP_CFPC], sPAPRMachineState),
> +        VMSTATE_END_OF_LIST()
> +    },
> +};

Hrm, some macros to build these would probably be a good idea..

>  void spapr_caps_reset(sPAPRMachineState *spapr)
>  {
>      sPAPRCapabilities default_caps;
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 61bb3632c4..ff476693d1 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -60,8 +60,10 @@ typedef enum {
>  #define SPAPR_CAP_VSX                   0x01
>  /* Decimal Floating Point */
>  #define SPAPR_CAP_DFP                   0x02
> +/* Cache Flush on Privilege Change */
> +#define SPAPR_CAP_CFPC                  0x03
>  /* Num Caps */
> -#define SPAPR_CAP_NUM                   (SPAPR_CAP_DFP + 1)
> +#define SPAPR_CAP_NUM                   (SPAPR_CAP_CFPC + 1)
>  
>  /*
>   * Capability Values
> @@ -779,6 +781,7 @@ int spapr_caps_pre_save(void *opaque);
>  extern const VMStateDescription vmstate_spapr_cap_htm;
>  extern const VMStateDescription vmstate_spapr_cap_vsx;
>  extern const VMStateDescription vmstate_spapr_cap_dfp;
> +extern const VMStateDescription vmstate_spapr_cap_cfpc;
>  
>  static inline uint8_t spapr_get_cap(sPAPRMachineState *spapr, int cap)
>  {