Reviewed-by: Glenn Miles <mil...@linux.ibm.com>
On Mon, 2025-05-12 at 13:10 +1000, Nicholas Piggin wrote:
> Further split xive_tctx_pipr_update() by splitting out a new function
> that is used to re-compute the PIPR from IPB. This is generally only
> used with XIVE1, because group interrputs require more logic.
>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
> ---
> hw/intc/xive.c | 25 ++++++++++++++++++++++---
> 1 file changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/hw/intc/xive.c b/hw/intc/xive.c
> index 25f6c69c44..5ff1b8f024 100644
> --- a/hw/intc/xive.c
> +++ b/hw/intc/xive.c
> @@ -225,6 +225,20 @@ void xive_tctx_pipr_update(XiveTCTX *tctx, uint8_t ring,
> uint8_t priority,
> xive_tctx_notify(tctx, ring, group_level);
> }
>
> +static void xive_tctx_pipr_recompute_from_ipb(XiveTCTX *tctx, uint8_t ring)
> +{
> + /* HV_POOL ring uses HV_PHYS NSR, CPPR and PIPR registers */
> + uint8_t alt_ring = (ring == TM_QW2_HV_POOL) ? TM_QW3_HV_PHYS : ring;
> + uint8_t *aregs = &tctx->regs[alt_ring];
> + uint8_t *regs = &tctx->regs[ring];
> +
> + /* Does not support a presented group interrupt */
> + g_assert(!xive_nsr_indicates_group_exception(alt_ring, aregs[TM_NSR]));
> +
> + aregs[TM_PIPR] = xive_ipb_to_pipr(regs[TM_IPB]);
> + xive_tctx_notify(tctx, ring, 0);
> +}
> +
> void xive_tctx_pipr_present(XiveTCTX *tctx, uint8_t ring, uint8_t priority,
> uint8_t group_level)
> {
> @@ -517,7 +531,12 @@ static void xive_tm_set_os_lgs(XivePresenter *xptr,
> XiveTCTX *tctx,
> static void xive_tm_set_os_pending(XivePresenter *xptr, XiveTCTX *tctx,
> hwaddr offset, uint64_t value, unsigned
> size)
> {
> - xive_tctx_pipr_update(tctx, TM_QW1_OS, value & 0xff, 0);
> + uint8_t ring = TM_QW1_OS;
> + uint8_t *regs = &tctx->regs[ring];
> +
> + /* XXX: how should this work exactly? */
> + regs[TM_IPB] |= xive_priority_to_ipb(value & 0xff);
> + xive_tctx_pipr_recompute_from_ipb(tctx, ring);
> }
>
> static void xive_os_cam_decode(uint32_t cam, uint8_t *nvt_blk,
> @@ -601,14 +620,14 @@ static void xive_tctx_need_resend(XiveRouter *xrtr,
> XiveTCTX *tctx,
> }
>
> /*
> - * Always call xive_tctx_pipr_update(). Even if there were no
> + * Always call xive_tctx_recompute_from_ipb(). Even if there were no
> * escalation triggered, there could be a pending interrupt which
> * was saved when the context was pulled and that we need to take
> * into account by recalculating the PIPR (which is not
> * saved/restored).
> * It will also raise the External interrupt signal if needed.
> */
> - xive_tctx_pipr_update(tctx, TM_QW1_OS, 0xFF, 0); /* fxb */
> + xive_tctx_pipr_recompute_from_ipb(tctx, TM_QW1_OS); /* fxb */
> }
>
> /*
