[PATCH 2/7] spapr, xive: Turn "nr-ends" property into "nr-servers" property

[Greg Kurz]

The sPAPR XIVE object has an nr_ends field which happens to be a
multiple of spapr_max_server_number(). It is currently set with
the help of "nr-ends" property. This is a bit unfortunate since
it exposes to the sPAPR irq frontend what should remain an
implemantation detail within the XIVE backend.

It will be possible soon to inform the XIVE KVM device about the
range of VCPU ids that may be used in the VM, as returned by the
spapr_max_server_number() function. This will allow the device
to substantially reduce the consumption of scarce resources
in the XIVE HW.

For both reasons, replace the "nr-ends" property with an "nr-servers"
one. The existing nr_ends field must be kept though since it tells how
many ENDs are migrated, it is derived from "nr-servers" at realize time
for simplicity. Convert spapr_dt_xive() to use it as well.

Signed-off-by: Greg Kurz <address@hidden>
---
 hw/intc/spapr_xive.c        |   21 ++++++++++++++++-----
 hw/ppc/spapr_irq.c          |    2 +-
 include/hw/ppc/spapr_xive.h |    1 +
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c
index 04879abf2e7a..62888ddc68db 100644
--- a/hw/intc/spapr_xive.c
+++ b/hw/intc/spapr_xive.c
@@ -99,6 +99,15 @@ int spapr_xive_end_to_target(uint8_t end_blk, uint32_t 
end_idx,
     return 0;
 }
 
+static uint32_t spapr_xive_vcpu_id_to_end_idx(uint32_t vcpu_id)
+{
+    /*
+     * 8 XIVE END structures per CPU. One for each available
+     * priority
+     */
+    return vcpu_id << 3;
+}
+
 static void spapr_xive_cpu_to_end(PowerPCCPU *cpu, uint8_t prio,
                                   uint8_t *out_end_blk, uint32_t *out_end_idx)
 {
@@ -109,7 +118,7 @@ static void spapr_xive_cpu_to_end(PowerPCCPU *cpu, uint8_t 
prio,
     }
 
     if (out_end_idx) {
-        *out_end_idx = (cpu->vcpu_id << 3) + prio;
+        *out_end_idx = spapr_xive_vcpu_id_to_end_idx(cpu->vcpu_id) + prio;
     }
 }
 
@@ -283,11 +292,13 @@ static void spapr_xive_realize(DeviceState *dev, Error 
**errp)
         return;
     }
 
-    if (!xive->nr_ends) {
-        error_setg(errp, "Number of interrupt needs to be greater 0");
+    if (!xive->nr_servers) {
+        error_setg(errp, "Number of interrupt servers must be greater than 0");
         return;
     }
 
+    xive->nr_ends = spapr_xive_vcpu_id_to_end_idx(xive->nr_servers);
+
     /*
      * Initialize the internal sources, for IPIs and virtual devices.
      */
@@ -489,7 +500,7 @@ static const VMStateDescription vmstate_spapr_xive = {
 
 static Property spapr_xive_properties[] = {
     DEFINE_PROP_UINT32("nr-irqs", SpaprXive, nr_irqs, 0),
-    DEFINE_PROP_UINT32("nr-ends", SpaprXive, nr_ends, 0),
+    DEFINE_PROP_UINT32("nr-servers", SpaprXive, nr_servers, 0),
     DEFINE_PROP_UINT64("vc-base", SpaprXive, vc_base, SPAPR_XIVE_VC_BASE),
     DEFINE_PROP_UINT64("tm-base", SpaprXive, tm_base, SPAPR_XIVE_TM_BASE),
     DEFINE_PROP_END_OF_LIST(),
@@ -1550,7 +1561,7 @@ void spapr_dt_xive(SpaprMachineState *spapr, uint32_t 
nr_servers, void *fdt,
     /* Interrupt number ranges for the IPIs */
     uint32_t lisn_ranges[] = {
         cpu_to_be32(0),
-        cpu_to_be32(nr_servers),
+        cpu_to_be32(xive->nr_servers),
     };
     /*
      * EQ size - the sizes of pages supported by the system 4K, 64K,
diff --git a/hw/ppc/spapr_irq.c b/hw/ppc/spapr_irq.c
index 457eabe24cda..025fd00143a2 100644
--- a/hw/ppc/spapr_irq.c
+++ b/hw/ppc/spapr_irq.c
@@ -591,7 +591,7 @@ void spapr_irq_init(SpaprMachineState *spapr, Error **errp)
          * 8 XIVE END structures per CPU. One for each available
          * priority
          */
-        qdev_prop_set_uint32(dev, "nr-ends", nr_servers << 3);
+        qdev_prop_set_uint32(dev, "nr-servers", nr_servers);
         qdev_init_nofail(dev);
 
         spapr->xive = SPAPR_XIVE(dev);
diff --git a/include/hw/ppc/spapr_xive.h b/include/hw/ppc/spapr_xive.h
index 0df20a6590a5..4a4a6fc6be7f 100644
--- a/include/hw/ppc/spapr_xive.h
+++ b/include/hw/ppc/spapr_xive.h
@@ -22,6 +22,7 @@ typedef struct SpaprXive {
     /* Internal interrupt source for IPIs and virtual devices */
     XiveSource    source;
     hwaddr        vc_base;
+    uint32_t      nr_servers;
 
     /* END ESB MMIOs */
     XiveENDSource end_source;