[Qemu-devel] [PATCH 20/28] Add PAPR H_VIO_SIGNAL hypercall and infrastructure for VIO interrupts

[qemu@gibson.dropbear.id.au]

From: David Gibson <david@gibson.dropbear.id.au>

This patch adds infrastructure to support interrupts from PAPR virtual IO
devices.  This includes correctly advertising those interrupts in the
device tree, and implementing the H_VIO_SIGNAL hypercall, used to
enable and disable individual device interrupts.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
---
 hw/spapr.c     |    2 +-
 hw/spapr_vio.c |   34 ++++++++++++++++++++++++++++++++++
 hw/spapr_vio.h |    6 ++++++
 3 files changed, 41 insertions(+), 1 deletions(-)

diff --git a/hw/spapr.c b/hw/spapr.c
index be30def..5b19963 100644
--- a/hw/spapr.c
+++ b/hw/spapr.c
@@ -62,7 +62,7 @@ static void *spapr_create_fdt(int *fdt_size, ram_addr_t ramsize,
     uint32_t start_prop = cpu_to_be32(initrd_base);
     uint32_t end_prop = cpu_to_be32(initrd_base + initrd_size);
     uint32_t pft_size_prop[] = {0, cpu_to_be32(hash_shift)};
-    char hypertas_prop[] = "hcall-pft\0hcall-term\0hcall-dabr";
+    char hypertas_prop[] = "hcall-pft\0hcall-term\0hcall-dabr\0hcall-interrupt";
     uint32_t interrupt_server_ranges_prop[] = {0, cpu_to_be32(smp_cpus)};
     int i;
     char *modelname;
diff --git a/hw/spapr_vio.c b/hw/spapr_vio.c
index 67005bb..b01331d 100644
--- a/hw/spapr_vio.c
+++ b/hw/spapr_vio.c
@@ -105,6 +105,15 @@ static int vio_make_devnode(VIOsPAPRDevice *dev,
         }
     }
 
+    if (dev->qirq) {
+        uint32_t ints_prop[] = {cpu_to_be32(dev->vio_irq_num), 0};
+
+        ret = fdt_setprop(fdt, node_off, "interrupts", ints_prop,
+                          sizeof(ints_prop));
+        if (ret < 0)
+            return ret;
+    }
+
     if (info->devnode) {
         ret = (info->devnode)(dev, fdt, node_off);
         if (ret < 0) {
@@ -140,6 +149,28 @@ void spapr_vio_bus_register_withprop(VIOsPAPRDeviceInfo *info)
     qdev_register(&info->qdev);
 }
 
+static target_ulong h_vio_signal(CPUState *env, sPAPREnvironment *spapr,
+                                 target_ulong opcode,
+                                 target_ulong *args)
+{
+    target_ulong reg = args[0];
+    target_ulong mode = args[1];
+    VIOsPAPRDevice *dev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
+    VIOsPAPRDeviceInfo *info;
+
+    if (!dev)
+        return H_PARAMETER;
+
+    info = (VIOsPAPRDeviceInfo *)dev->qdev.info;
+
+    if (mode & ~info->signal_mask)
+        return H_PARAMETER;;
+
+    dev->signal_state = mode;
+
+    return H_SUCCESS;
+}
+
 VIOsPAPRBus *spapr_vio_bus_init(void)
 {
     VIOsPAPRBus *bus;
@@ -156,6 +187,9 @@ VIOsPAPRBus *spapr_vio_bus_init(void)
     _bus = qbus_create(&spapr_vio_bus_info, dev, "spapr-vio");
     bus = DO_UPCAST(VIOsPAPRBus, bus, _bus);
 
+    /* hcall-vio */
+    spapr_register_hypercall(H_VIO_SIGNAL, h_vio_signal);
+
     for (_info = device_info_list; _info; _info = _info->next) {
         VIOsPAPRDeviceInfo *info = (VIOsPAPRDeviceInfo *)_info;
 
diff --git a/hw/spapr_vio.h b/hw/spapr_vio.h
index b164ad3..8a000c6 100644
--- a/hw/spapr_vio.h
+++ b/hw/spapr_vio.h
@@ -24,6 +24,9 @@
 typedef struct VIOsPAPRDevice {
     DeviceState qdev;
     uint32_t reg;
+    qemu_irq qirq;
+    uint32_t vio_irq_num;
+    target_ulong signal_state;
 } VIOsPAPRDevice;
 
 typedef struct VIOsPAPRBus {
@@ -33,6 +36,7 @@ typedef struct VIOsPAPRBus {
 typedef struct {
     DeviceInfo qdev;
     const char *dt_name, *dt_type, *dt_compatible;
+    target_ulong signal_mask;
     int (*init)(VIOsPAPRDevice *dev);
     void (*hcalls)(VIOsPAPRBus *bus);
     int (*devnode)(VIOsPAPRDevice *dev, void *fdt, int node_off);
@@ -43,6 +47,8 @@ extern VIOsPAPRDevice *spapr_vio_find_by_reg(VIOsPAPRBus *bus, uint32_t reg);
 extern void spapr_vio_bus_register_withprop(VIOsPAPRDeviceInfo *info);
 extern int spapr_populate_vdevice(VIOsPAPRBus *bus, void *fdt);
 
+extern int spapr_vio_signal(VIOsPAPRDevice *dev, target_ulong mode);
+
 void vty_putchars(VIOsPAPRDevice *sdev, uint8_t *buf, int len);
 void spapr_vty_create(VIOsPAPRBus *bus,
                       uint32_t reg, CharDriverState *chardev);
-- 
1.7.1