[Qemu-devel] [PATCH] pseries: added allocator for a block of IRQs

[Alexey Kardashevskiy <aik@ozlabs.ru>]

The patch adds a simple helper which allocates a consecutive sequence
of IRQs calling spapr_allocate_irq for each and checks that allocated
IRQs go consequently.

The patch is required for upcoming support of MSI/MSIX on POWER.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 hw/spapr.c |   20 ++++++++++++++++++++
 hw/spapr.h |    1 +
 2 files changed, 21 insertions(+)

diff --git a/hw/spapr.c b/hw/spapr.c
index 6a9a7ca..f47c109 100644
--- a/hw/spapr.c
+++ b/hw/spapr.c
@@ -113,6 +113,26 @@ qemu_irq spapr_allocate_irq(uint32_t hint, uint32_t *irq_num,
     return qirq;
 }
 
+/* Allocate block of consequtive IRQs, returns a number of the first */
+int spapr_allocate_irq_block(uint32_t num, enum xics_irq_type type)
+{
+    int i, ret;
+    uint32_t irq = -1;
+
+    for (i = 0; i < num; ++i) {
+        if (!spapr_allocate_irq(0, &irq, type)) {
+            return -1;
+        }
+        if (0 == i) {
+            ret = irq;
+        }
+        if (ret + i != irq) {
+            return -1;
+        }
+    }
+    return ret;
+}
+
 static int spapr_fixup_cpu_dt(void *fdt, sPAPREnvironment *spapr)
 {
     int ret = 0, offset;
diff --git a/hw/spapr.h b/hw/spapr.h
index d0c1749..4a3520f 100644
--- a/hw/spapr.h
+++ b/hw/spapr.h
@@ -289,6 +289,7 @@ target_ulong spapr_hypercall(CPUPPCState *env, target_ulong opcode,
 
 qemu_irq spapr_allocate_irq(uint32_t hint, uint32_t *irq_num,
                             enum xics_irq_type type);
+int spapr_allocate_irq_block(uint32_t num, enum xics_irq_type type);
 
 static inline qemu_irq spapr_allocate_msi(uint32_t hint, uint32_t *irq_num)
 {
-- 
1.7.10