ppc/xive: Add support for PQ state bits offload

The trigger message coming from a HW source contains a special bit
informing the XIVE interrupt controller that the PQ bits have been
checked at the source or not. Depending on the value, the IC can
perform the check and the state transition locally using its own PQ
state bits.

The following changes add new accessors to the XiveRouter required to
query and update the PQ state bits. This only applies to the PowerNV
machine. sPAPR accessors are provided but the pSeries machine should
not be concerned by such complex configuration for the moment.

Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

1 files changed, 34 insertions, 3 deletions

diff --git a/hw/intc/pnv_xive.c b/hw/intc/pnv_xive.c
index 621b20a..1ce1d7b 100644
--- a/hw/intc/pnv_xive.c
+++ b/hw/intc/pnv_xive.c
@@ -403,6 +403,34 @@ static int pnv_xive_get_eas(XiveRouter *xrtr, uint8_t blk, uint32_t idx,
     return pnv_xive_vst_read(xive, VST_TSEL_IVT, blk, idx, eas);
 }
 
+static int pnv_xive_get_pq(XiveRouter *xrtr, uint8_t blk, uint32_t idx,
+                           uint8_t *pq)
+{
+    PnvXive *xive = PNV_XIVE(xrtr);
+
+    if (pnv_xive_block_id(xive) != blk) {
+        xive_error(xive, "VST: EAS %x is remote !?", XIVE_EAS(blk, idx));
+        return -1;
+    }
+
+    *pq = xive_source_esb_get(&xive->ipi_source, idx);
+    return 0;
+}
+
+static int pnv_xive_set_pq(XiveRouter *xrtr, uint8_t blk, uint32_t idx,
+                           uint8_t *pq)
+{
+    PnvXive *xive = PNV_XIVE(xrtr);
+
+    if (pnv_xive_block_id(xive) != blk) {
+        xive_error(xive, "VST: EAS %x is remote !?", XIVE_EAS(blk, idx));
+        return -1;
+    }
+
+    *pq = xive_source_esb_set(&xive->ipi_source, idx, *pq);
+    return 0;
+}
+
 /*
  * One bit per thread id. The first register PC_THREAD_EN_REG0 covers
  * the first cores 0-15 (normal) of the chip or 0-7 (fused). The
@@ -499,12 +527,12 @@ static PnvXive *pnv_xive_tm_get_xive(PowerPCCPU *cpu)
  * event notification to the Router. This is required on a multichip
  * system.
  */
-static void pnv_xive_notify(XiveNotifier *xn, uint32_t srcno)
+static void pnv_xive_notify(XiveNotifier *xn, uint32_t srcno, bool pq_checked)
 {
     PnvXive *xive = PNV_XIVE(xn);
     uint8_t blk = pnv_xive_block_id(xive);
 
-    xive_router_notify(xn, XIVE_EAS(blk, srcno));
+    xive_router_notify(xn, XIVE_EAS(blk, srcno), pq_checked);
 }
 
 /*
@@ -1351,7 +1379,8 @@ static void pnv_xive_ic_hw_trigger(PnvXive *xive, hwaddr addr, uint64_t val)
     blk = XIVE_EAS_BLOCK(val);
     idx = XIVE_EAS_INDEX(val);
 
-    xive_router_notify(XIVE_NOTIFIER(xive), XIVE_EAS(blk, idx));
+    xive_router_notify(XIVE_NOTIFIER(xive), XIVE_EAS(blk, idx),
+                       !!(val & XIVE_TRIGGER_PQ));
 }
 
 static void pnv_xive_ic_notify_write(void *opaque, hwaddr addr, uint64_t val,
@@ -1971,6 +2000,8 @@ static void pnv_xive_class_init(ObjectClass *klass, void *data)
     device_class_set_props(dc, pnv_xive_properties);
 
     xrc->get_eas = pnv_xive_get_eas;
+    xrc->get_pq = pnv_xive_get_pq;
+    xrc->set_pq = pnv_xive_set_pq;
     xrc->get_end = pnv_xive_get_end;
     xrc->write_end = pnv_xive_write_end;
     xrc->get_nvt = pnv_xive_get_nvt;