pnv_phb4_pec.c: move pnv_pec_phb_offset() to pnv_phb4.c

The logic inside pnv_pec_phb_offset() will be useful in the next patch
to determine the stack that should contain a PHB4 device.

Move the function to pnv_phb4.c and make it public since there's no
pnv_phb4_pec.h header. While we're at it, add 'stack_index' as a
parameter and make the function return 'phb-id' directly. And rename it
to pnv_phb4_pec_get_phb_id() to be even clearer about the function
intent.

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220110143346.455901-3-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index 83dedc878a..2223b985b2 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -1070,6 +1070,23 @@ static const TypeInfo pnv_phb4_iommu_memory_region_info = {
 };
 
 /*
+ * Return the index/phb-id of a PHB4 that belongs to a
+ * pec->stacks[stack_index] stack.
+ */
+int pnv_phb4_pec_get_phb_id(PnvPhb4PecState *pec, int stack_index)
+{
+    PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(pec);
+    int index = pec->index;
+    int offset = 0;
+
+    while (index--) {
+        offset += pecc->num_stacks[index];
+    }
+
+    return offset + stack_index;
+}
+
+/*
  * MSI/MSIX memory region implementation.
  * The handler handles both MSI and MSIX.
  */