[Qemu-devel] [RFC 6/8] isa: use memory regions instead of portio_list_* functions

[Hervé Poussineau]

Signed-off-by: Hervé Poussineau <address@hidden>
---
 hw/isa-bus.c |  127 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 hw/isa.h     |    2 +-
 2 files changed, 125 insertions(+), 4 deletions(-)

diff --git a/hw/isa-bus.c b/hw/isa-bus.c
index 144a88e..d22f432 100644
--- a/hw/isa-bus.c
+++ b/hw/isa-bus.c
@@ -104,19 +104,140 @@ void isa_register_ioport(ISADevice *dev, MemoryRegion 
*io, uint16_t start)
     isa_init_ioport(dev, start);
 }
 
+typedef struct PortioState {
+    const char *name; /* debug purposes */
+    uint16_t start;
+    uint16_t offset;
+    const MemoryRegionPortio *pio_start;
+    void *opaque;
+} PortioState;
+
+static const MemoryRegionPortio *portio_find(const MemoryRegionPortio *mrp,
+                                             uint64_t offset,
+                                             unsigned int width, bool write,
+                                             bool smaller)
+{
+    for (; mrp->size; ++mrp) {
+        if (offset >= mrp->offset && offset < mrp->offset + mrp->len
+            && (width == mrp->size || (smaller && width < mrp->size))
+            && (write ? (bool)mrp->write : (bool)mrp->read)) {
+            return mrp;
+        }
+    }
+    return NULL;
+}
+
+static uint64_t portio_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    const PortioState *s = opaque;
+    const MemoryRegionPortio *mrp;
+
+    addr += s->offset;
+    mrp = portio_find(s->pio_start, addr, size, false, false);
+    if (mrp) {
+        return mrp->read(s->opaque, s->start + addr);
+    } else if (size == 2) {
+        uint64_t data;
+        mrp = portio_find(s->pio_start, addr, 1, false, false);
+        assert(mrp);
+        data = mrp->read(s->opaque, s->start + addr) |
+              (mrp->read(s->opaque, s->start + addr + 1) << 8);
+        return data;
+    }
+    qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid read from 0x%x size=%d",
+                  s->name, s->start + (int)addr, size);
+    return -1U;
+}
+
+static void portio_write(void *opaque, hwaddr addr, uint64_t data,
+                         unsigned int size)
+{
+    const PortioState *s = opaque;
+    const MemoryRegionPortio *mrp;
+
+    addr += s->offset;
+    mrp = portio_find(s->pio_start, addr, size, true, false);
+    if (mrp) {
+        mrp->write(s->opaque, s->start + addr, data);
+        return;
+    } else if (size == 2) {
+        mrp = portio_find(s->pio_start, addr, 1, true, false);
+        assert(mrp);
+        mrp->write(s->opaque, s->start + addr, data & 0xff);
+        mrp->write(s->opaque, s->start + addr + 1, data >> 8);
+        return;
+    }
+    qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid write to 0x%x size=%d",
+                  s->name, s->start + (int)addr, size);
+}
+
+static bool portio_accepts(void *opaque, hwaddr addr, unsigned int size,
+                           bool is_write)
+{
+    const PortioState *s = opaque;
+    const MemoryRegionPortio *mrp;
+
+    addr += s->offset;
+    mrp = portio_find(s->pio_start, addr, size, is_write, true);
+    return (mrp != NULL);
+}
+
+const MemoryRegionOps portio_ops = {
+    .read = portio_read,
+    .write = portio_write,
+    .valid.accepts = portio_accepts,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+};
+
+static void isa_register_portio_list_1(ISADevice *dev, uint16_t start,
+                                       uint16_t offset, uint16_t end,
+                                       const MemoryRegionPortio *pio_start,
+                                       void *opaque, const char *name)
+{
+    MemoryRegion *mr = g_new(MemoryRegion, 1);
+    PortioState *s = g_new(PortioState, 1);
+
+    s->name = name;
+    s->start = start;
+    s->offset = offset;
+    s->pio_start = pio_start;
+    s->opaque = opaque;
+    memory_region_init_io(mr, &portio_ops, s, name, end - offset);
+    memory_region_add_subregion(isa_address_space_io(dev),
+                                start + offset, mr);
+}
+
 void isa_register_portio_list(ISADevice *dev, uint16_t start,
                               const MemoryRegionPortio *pio_start,
                               void *opaque, const char *name)
 {
-    PortioList *piolist = g_new(PortioList, 1);
+    const MemoryRegionPortio *pio, *first;
+    uint16_t end;
 
     /* START is how we should treat DEV, regardless of the actual
        contents of the portio array.  This is how the old code
        actually handled e.g. the FDC device.  */
     isa_init_ioport(dev, start);
 
-    portio_list_init(piolist, pio_start, opaque, name);
-    portio_list_add(piolist, isabus->address_space_io, start);
+    assert(pio_start->size);
+
+    first = pio_start;
+    end = 0;
+    for (pio = pio_start; pio->size; pio++) {
+        assert(pio->offset >= first->offset);
+        if (pio->offset > first->offset + first->len) {
+            isa_register_portio_list_1(dev, start, first->offset, end,
+                                       pio_start, opaque, name);
+            first = pio;
+            end = 0;
+        }
+        if (pio->offset + pio->len > end) {
+            end = pio->offset + pio->len;
+        }
+    }
+
+    isa_register_portio_list_1(dev, start, first->offset, end,
+                               pio_start, opaque, name);
 }
 
 static int isa_qdev_init(DeviceState *qdev)
diff --git a/hw/isa.h b/hw/isa.h
index 9d719fa..d44d16d 100644
--- a/hw/isa.h
+++ b/hw/isa.h
@@ -73,7 +73,7 @@ void isa_register_ioport(ISADevice *dev, MemoryRegion *io, 
uint16_t start);
  * @dev: the ISADevice against which these are registered; may be NULL.
  * @start: the base I/O port against which the portio->offset is applied.
  * @portio: the ports, sorted by offset.
- * @opaque: passed into the old_portio callbacks.
+ * @opaque: passed into the portio callbacks.
  * @name: passed into memory_region_init_io.
  */
 void isa_register_portio_list(ISADevice *dev, uint16_t start,
-- 
1.7.10.4