Re: [PATCH 49/50] ppc/xive: Split need_resend into restore_nvp

[Mike Kowal]

On 5/11/2025 10:10 PM, Nicholas Piggin wrote:

This is needed by the next patch which will re-send on all lower
rings when pushing a context.

Reviewed-by: Michael Kowal<ko...@linux.ibm.com>

Thanks,  MAK

Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
  hw/intc/xive.c  | 24 ++++++++++++------------
  hw/intc/xive2.c | 28 ++++++++++++++++------------
  2 files changed, 28 insertions(+), 24 deletions(-)

diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index 69118999e6..9ade9ec6c1 100644
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -606,7 +606,7 @@ static uint64_t xive_tm_pull_os_ctx(XivePresenter *xptr, 
XiveTCTX *tctx,
      return qw1w2;
  }

-static void xive_tctx_need_resend(XiveRouter *xrtr, XiveTCTX *tctx,

+static void xive_tctx_restore_nvp(XiveRouter *xrtr, XiveTCTX *tctx,
                                    uint8_t nvt_blk, uint32_t nvt_idx)
  {
      XiveNVT nvt;
@@ -632,16 +632,6 @@ static void xive_tctx_need_resend(XiveRouter *xrtr, 
XiveTCTX *tctx,
          uint8_t *regs = &tctx->regs[TM_QW1_OS];
          regs[TM_IPB] |= ipb;
      }
-
-    /*
-     * 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_recompute_from_ipb(tctx, TM_QW1_OS); /* fxb */
  }

/*

@@ -663,7 +653,17 @@ static void xive_tm_push_os_ctx(XivePresenter *xptr, 
XiveTCTX *tctx,

/* Check the interrupt pending bits */

      if (vo) {
-        xive_tctx_need_resend(XIVE_ROUTER(xptr), tctx, nvt_blk, nvt_idx);
+        xive_tctx_restore_nvp(XIVE_ROUTER(xptr), tctx, nvt_blk, nvt_idx);
+
+        /*
+         * 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_recompute_from_ipb(tctx, TM_QW1_OS); /* fxb */
      }
  }

diff --git a/hw/intc/xive2.c b/hw/intc/xive2.c

index a9b188b909..53e90b8178 100644
--- a/hw/intc/xive2.c
+++ b/hw/intc/xive2.c
@@ -940,14 +940,14 @@ static uint8_t xive2_tctx_restore_ctx(Xive2Router *xrtr, 
XiveTCTX *tctx,
      return cppr;
  }

-static void xive2_tctx_need_resend(Xive2Router *xrtr, XiveTCTX *tctx,

+/* Restore TIMA VP context from NVP backlog */
+static void xive2_tctx_restore_nvp(Xive2Router *xrtr, XiveTCTX *tctx,
                                     uint8_t ring,
                                     uint8_t nvp_blk, uint32_t nvp_idx,
                                     bool do_restore)
  {
-    uint8_t *sig_regs = xive_tctx_signal_regs(tctx, ring);
      uint8_t *regs = &tctx->regs[ring];
-    uint8_t ipb, nsr = sig_regs[TM_NSR];
+    uint8_t ipb;
      Xive2Nvp nvp;

/*

@@ -978,14 +978,6 @@ static void xive2_tctx_need_resend(Xive2Router *xrtr, 
XiveTCTX *tctx,
      }
      /* IPB bits in the backlog are merged with the TIMA IPB bits */
      regs[TM_IPB] |= ipb;
-
-    if (xive_nsr_indicates_group_exception(ring, nsr)) {
-        /* redistribute precluded active grp interrupt */
-        g_assert(ring == TM_QW2_HV_POOL); /* PHYS ring has the grp interrupt */
-        xive2_redistribute(xrtr, tctx, xive_nsr_exception_ring(ring, nsr));
-    }
-    xive2_tctx_process_pending(tctx, ring == TM_QW2_HV_POOL ?
-                                         TM_QW3_HV_PHYS : ring);
  }

/*

@@ -1028,8 +1020,20 @@ static void xive2_tm_push_ctx(XivePresenter *xptr, 
XiveTCTX *tctx,

/* Check the interrupt pending bits */

      if (v) {
-        xive2_tctx_need_resend(XIVE2_ROUTER(xptr), tctx, ring,
+        Xive2Router *xrtr = XIVE2_ROUTER(xptr);
+        uint8_t *sig_regs = xive_tctx_signal_regs(tctx, ring);
+        uint8_t nsr = sig_regs[TM_NSR];
+
+        xive2_tctx_restore_nvp(xrtr, tctx, ring,
                                 nvp_blk, nvp_idx, do_restore);
+
+        if (xive_nsr_indicates_group_exception(ring, nsr)) {
+            /* redistribute precluded active grp interrupt */
+            g_assert(ring == TM_QW2_HV_POOL); /* PHYS ring has the interrupt */
+            xive2_redistribute(xrtr, tctx, xive_nsr_exception_ring(ring, nsr));
+        }
+        xive2_tctx_process_pending(tctx, ring == TM_QW2_HV_POOL ?
+                                                 TM_QW3_HV_PHYS : ring);
      }
  }