[PATCH v6 20/20] ppc/pnv: Dump the XIVE NVT table

["Cédric Le Goater" <clg@kaod.org>]

This is useful to dump the saved contexts of the vCPUs : configuration
of the base END index of the vCPU and the Interrupt Pending Buffer
register, which is updated when an interrupt can not be presented.

When dumping the NVT table, we skip empty indirect pages which are not
necessarily allocated.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 include/hw/ppc/xive_regs.h |  3 ++
 hw/intc/pnv_xive.c         | 64 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/include/hw/ppc/xive_regs.h b/include/hw/ppc/xive_regs.h
index 1a5622f8ded8..09f243600c5d 100644
--- a/include/hw/ppc/xive_regs.h
+++ b/include/hw/ppc/xive_regs.h
@@ -252,6 +252,8 @@ typedef struct XiveNVT {
         uint32_t        w0;
 #define NVT_W0_VALID             PPC_BIT32(0)
         uint32_t        w1;
+#define NVT_W1_EQ_BLOCK          PPC_BITMASK32(0, 3)
+#define NVT_W1_EQ_INDEX          PPC_BITMASK32(4, 31)
         uint32_t        w2;
         uint32_t        w3;
         uint32_t        w4;
@@ -277,6 +279,7 @@ typedef struct XiveNVT {
  * field of the XIVE END
  */
 #define XIVE_NVT_SHIFT                19
+#define XIVE_NVT_COUNT                (1 << XIVE_NVT_SHIFT)
 
 static inline uint32_t xive_nvt_cam_line(uint8_t nvt_blk, uint32_t nvt_idx)
 {
diff --git a/hw/intc/pnv_xive.c b/hw/intc/pnv_xive.c
index 43c760efd137..a0a69b98a713 100644
--- a/hw/intc/pnv_xive.c
+++ b/hw/intc/pnv_xive.c
@@ -527,6 +527,44 @@ static uint32_t pnv_xive_nr_ipis(PnvXive *xive, uint8_t blk)
     return VSD_INDIRECT & vsd ? 0 : vst_tsize * SBE_PER_BYTE;
 }
 
+/*
+ * Compute the number of entries per indirect subpage.
+ */
+static uint64_t pnv_xive_vst_per_subpage(PnvXive *xive, uint32_t type)
+{
+    uint8_t blk = pnv_xive_block_id(xive);
+    uint64_t vsd = xive->vsds[type][blk];
+    const XiveVstInfo *info = &vst_infos[type];
+    uint64_t vsd_addr;
+    uint32_t page_shift;
+
+    /* For direct tables, fake a valid value */
+    if (!(VSD_INDIRECT & vsd)) {
+        return 1;
+    }
+
+    /* Get the page size of the indirect table. */
+    vsd_addr = vsd & VSD_ADDRESS_MASK;
+    vsd = ldq_be_dma(&address_space_memory, vsd_addr);
+
+    if (!(vsd & VSD_ADDRESS_MASK)) {
+#ifdef XIVE_DEBUG
+        xive_error(xive, "VST: invalid %s entry %x !?", info->name, idx);
+#endif
+        return 0;
+    }
+
+    page_shift = GETFIELD(VSD_TSIZE, vsd) + 12;
+
+    if (!pnv_xive_vst_page_size_allowed(page_shift)) {
+        xive_error(xive, "VST: invalid %s page shift %d", info->name,
+                   page_shift);
+        return 0;
+    }
+
+    return (1ull << page_shift) / info->size;
+}
+
 /*
  * EDT Table
  *
@@ -1665,6 +1703,21 @@ static const MemoryRegionOps pnv_xive_pc_ops = {
     },
 };
 
+static void xive_nvt_pic_print_info(XiveNVT *nvt, uint32_t nvt_idx,
+                                    Monitor *mon)
+{
+    uint8_t  eq_blk = xive_get_field32(NVT_W1_EQ_BLOCK, nvt->w1);
+    uint32_t eq_idx = xive_get_field32(NVT_W1_EQ_INDEX, nvt->w1);
+
+    if (!xive_nvt_is_valid(nvt)) {
+        return;
+    }
+
+    monitor_printf(mon, "  %08x end:%02x/%04x IPB:%02x\n", nvt_idx,
+                   eq_blk, eq_idx,
+                   xive_get_field32(NVT_W4_IPB, nvt->w4));
+}
+
 void pnv_xive_pic_print_info(PnvXive *xive, Monitor *mon)
 {
     XiveRouter *xrtr = XIVE_ROUTER(xive);
@@ -1674,7 +1727,9 @@ void pnv_xive_pic_print_info(PnvXive *xive, Monitor *mon)
     uint32_t nr_ipis = pnv_xive_nr_ipis(xive, blk);
     XiveEAS eas;
     XiveEND end;
+    XiveNVT nvt;
     int i;
+    uint64_t xive_nvt_per_subpage;
 
     monitor_printf(mon, "XIVE[%x] #%d Source %08x .. %08x\n", chip_id, blk,
                    srcno0, srcno0 + nr_ipis - 1);
@@ -1702,6 +1757,15 @@ void pnv_xive_pic_print_info(PnvXive *xive, Monitor *mon)
     while (!xive_router_get_end(xrtr, blk, i, &end)) {
         xive_end_eas_pic_print_info(&end, i++, mon);
     }
+
+    monitor_printf(mon, "XIVE[%x] #%d NVTT %08x .. %08x\n", chip_id, blk,
+                   0, XIVE_NVT_COUNT - 1);
+    xive_nvt_per_subpage = pnv_xive_vst_per_subpage(xive, VST_TSEL_VPDT);
+    for (i = 0; i < XIVE_NVT_COUNT; i += xive_nvt_per_subpage) {
+        while (!xive_router_get_nvt(xrtr, blk, i, &nvt)) {
+            xive_nvt_pic_print_info(&nvt, i++, mon);
+        }
+    }
 }
 
 static void pnv_xive_reset(void *dev)
-- 
2.21.0