[for-5.0,v5,08/23] ppc/xive: Introduce a XivePresenter interface

When the XIVE IVRE sub-engine (XiveRouter) looks for a Notification
Virtual Target (NVT) to notify, it broadcasts a message on the
PowerBUS to find an XIVE IVPE sub-engine (Presenter) with the NVT
dispatched on one of its HW threads, and then forwards the
notification if any response was received.

The current XIVE presenter model is sufficient for the pseries machine
because it has a single interrupt controller device, but the PowerNV
machine can have multiple chips each having its own interrupt
controller. In this case, the XIVE presenter model is too simple and
the CAM line matching should scan all chips of the system.

To start fixing this issue, we first extend the XIVE Router model with
a new XivePresenter QOM interface representing the XIVE IVPE
sub-engine. This interface exposes a 'match_nvt' handler which the
sPAPR and PowerNV XIVE Router models will need to implement to perform
the CAM line matching.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 include/hw/ppc/xive.h | 32 ++++++++++++++++++++++++++++++++
 hw/intc/xive.c        | 26 +++++++++++++++++---------
 2 files changed, 49 insertions(+), 9 deletions(-)

On Fri, 15 Nov 2019 17:24:21 +0100
Cédric Le Goater <clg@kaod.org> wrote:

> When the XIVE IVRE sub-engine (XiveRouter) looks for a Notification
> Virtual Target (NVT) to notify, it broadcasts a message on the
> PowerBUS to find an XIVE IVPE sub-engine (Presenter) with the NVT
> dispatched on one of its HW threads, and then forwards the
> notification if any response was received.
> 
> The current XIVE presenter model is sufficient for the pseries machine
> because it has a single interrupt controller device, but the PowerNV
> machine can have multiple chips each having its own interrupt
> controller. In this case, the XIVE presenter model is too simple and
> the CAM line matching should scan all chips of the system.
> 
> To start fixing this issue, we first extend the XIVE Router model with
> a new XivePresenter QOM interface representing the XIVE IVPE
> sub-engine. This interface exposes a 'match_nvt' handler which the
> sPAPR and PowerNV XIVE Router models will need to implement to perform
> the CAM line matching.
> 
> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> ---
>  include/hw/ppc/xive.h | 32 ++++++++++++++++++++++++++++++++
>  hw/intc/xive.c        | 26 +++++++++++++++++---------
>  2 files changed, 49 insertions(+), 9 deletions(-)
> 
> diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h
> index fa7adf87feb2..f9aa0fa0dac3 100644
> --- a/include/hw/ppc/xive.h
> +++ b/include/hw/ppc/xive.h
> @@ -367,6 +367,38 @@ int xive_router_write_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
>  XiveTCTX *xive_router_get_tctx(XiveRouter *xrtr, CPUState *cs);
>  void xive_router_notify(XiveNotifier *xn, uint32_t lisn);
>  
> +/*
> + * XIVE Presenter
> + */
> +
> +typedef struct XiveTCTXMatch {
> +    XiveTCTX *tctx;
> +    uint8_t ring;
> +} XiveTCTXMatch;
> +

We recently decided to follow a strict CamelCase naming scheme in spapr.
We should probably do the same in other areas. Can you please make this
XiveTctxMatch ? I can send follow-up patches to convert the existing code
later on, ie. after this series is merged at last :)

The patch looks good anyway so:

Reviewed-by: Greg Kurz <groug@kaod.org>

> +typedef struct XivePresenter XivePresenter;
> +
> +#define TYPE_XIVE_PRESENTER "xive-presenter"
> +#define XIVE_PRESENTER(obj)                                     \
> +    INTERFACE_CHECK(XivePresenter, (obj), TYPE_XIVE_PRESENTER)
> +#define XIVE_PRESENTER_CLASS(klass)                                     \
> +    OBJECT_CLASS_CHECK(XivePresenterClass, (klass), TYPE_XIVE_PRESENTER)
> +#define XIVE_PRESENTER_GET_CLASS(obj)                                   \
> +    OBJECT_GET_CLASS(XivePresenterClass, (obj), TYPE_XIVE_PRESENTER)
> +
> +typedef struct XivePresenterClass {
> +    InterfaceClass parent;
> +    int (*match_nvt)(XivePresenter *xptr, uint8_t format,
> +                     uint8_t nvt_blk, uint32_t nvt_idx,
> +                     bool cam_ignore, uint8_t priority,
> +                     uint32_t logic_serv, XiveTCTXMatch *match);
> +} XivePresenterClass;
> +
> +int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx,
> +                              uint8_t format,
> +                              uint8_t nvt_blk, uint32_t nvt_idx,
> +                              bool cam_ignore, uint32_t logic_serv);
> +
>  /*
>   * XIVE END ESBs
>   */
> diff --git a/hw/intc/xive.c b/hw/intc/xive.c
> index 511e1a936347..344bb3f3bc4b 100644
> --- a/hw/intc/xive.c
> +++ b/hw/intc/xive.c
> @@ -1363,9 +1363,10 @@ static uint32_t xive_tctx_hw_cam_line(XiveTCTX *tctx)
>  /*
>   * The thread context register words are in big-endian format.
>   */
> -static int xive_presenter_tctx_match(XiveTCTX *tctx, uint8_t format,
> -                                     uint8_t nvt_blk, uint32_t nvt_idx,
> -                                     bool cam_ignore, uint32_t logic_serv)
> +int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx,
> +                              uint8_t format,
> +                              uint8_t nvt_blk, uint32_t nvt_idx,
> +                              bool cam_ignore, uint32_t logic_serv)
>  {
>      uint32_t cam = xive_nvt_cam_line(nvt_blk, nvt_idx);
>      uint32_t qw3w2 = xive_tctx_word2(&tctx->regs[TM_QW3_HV_PHYS]);
> @@ -1422,11 +1423,6 @@ static int xive_presenter_tctx_match(XiveTCTX *tctx, uint8_t format,
>      return -1;
>  }
>  
> -typedef struct XiveTCTXMatch {
> -    XiveTCTX *tctx;
> -    uint8_t ring;
> -} XiveTCTXMatch;
> -
>  static bool xive_presenter_match(XiveRouter *xrtr, uint8_t format,
>                                   uint8_t nvt_blk, uint32_t nvt_idx,
>                                   bool cam_ignore, uint8_t priority,
> @@ -1460,7 +1456,8 @@ static bool xive_presenter_match(XiveRouter *xrtr, uint8_t format,
>           * Check the thread context CAM lines and record matches. We
>           * will handle CPU exception delivery later
>           */
> -        ring = xive_presenter_tctx_match(tctx, format, nvt_blk, nvt_idx,
> +        ring = xive_presenter_tctx_match(XIVE_PRESENTER(xrtr), tctx, format,
> +                                         nvt_blk, nvt_idx,
>                                           cam_ignore, logic_serv);
>          /*
>           * Save the context and follow on to catch duplicates, that we
> @@ -1754,6 +1751,7 @@ static const TypeInfo xive_router_info = {
>      .class_init    = xive_router_class_init,
>      .interfaces    = (InterfaceInfo[]) {
>          { TYPE_XIVE_NOTIFIER },
> +        { TYPE_XIVE_PRESENTER },
>          { }
>      }
>  };
> @@ -1923,10 +1921,20 @@ static const TypeInfo xive_notifier_info = {
>      .class_size = sizeof(XiveNotifierClass),
>  };
>  
> +/*
> + * XIVE Presenter
> + */
> +static const TypeInfo xive_presenter_info = {
> +    .name = TYPE_XIVE_PRESENTER,
> +    .parent = TYPE_INTERFACE,
> +    .class_size = sizeof(XivePresenterClass),
> +};
> +
>  static void xive_register_types(void)
>  {
>      type_register_static(&xive_source_info);
>      type_register_static(&xive_notifier_info);
> +    type_register_static(&xive_presenter_info);
>      type_register_static(&xive_router_info);
>      type_register_static(&xive_end_source_info);
>      type_register_static(&xive_tctx_info);