VGA: Flush coalesced MMIO on related MMIO/PIO accesses

In preparation of stopping to flush coalesced MMIO unconditionally on
vmexits, mark VGA MMIO and PIO regions as synchronous /wrt coalesced
MMIO and flush the buffer explicitly on PIO accesses that do not use
generic memory regions yet.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

hw/cirrus_vga.c

@@ -2441,6 +2441,8 @@ static uint32_t cirrus_vga_ioport_read(void *opaque, uint32_t addr)
     VGACommonState *s = &c->vga;
     int val, index;
 
+    qemu_flush_coalesced_mmio_buffer();
+
     if (vga_ioport_invalid(s, addr)) {
 	val = 0xff;
     } else {
@@ -2534,6 +2536,8 @@ static void cirrus_vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
     VGACommonState *s = &c->vga;
     int index;
 
+    qemu_flush_coalesced_mmio_buffer();
+
     /* check port range access depending on color/monochrome mode */
     if (vga_ioport_invalid(s, addr)) {
 	return;
@@ -2854,6 +2858,7 @@ static void cirrus_init_common(CirrusVGAState * s, int device_id, int is_pci,
     /* I/O handler for LFB */
     memory_region_init_io(&s->cirrus_linear_io, &cirrus_linear_io_ops, s,
                           "cirrus-linear-io", VGA_RAM_SIZE);
+    memory_region_set_flush_coalesced(&s->cirrus_linear_io);
 
     /* I/O handler for LFB */
     memory_region_init_io(&s->cirrus_linear_bitblt_io,
@@ -2861,10 +2866,12 @@ static void cirrus_init_common(CirrusVGAState * s, int device_id, int is_pci,
                           s,
                           "cirrus-bitblt-mmio",
                           0x400000);
+    memory_region_set_flush_coalesced(&s->cirrus_linear_bitblt_io);
 
     /* I/O handler for memory-mapped I/O */
     memory_region_init_io(&s->cirrus_mmio_io, &cirrus_mmio_io_ops, s,
                           "cirrus-mmio", CIRRUS_PNPMMIO_SIZE);
+    memory_region_set_flush_coalesced(&s->cirrus_mmio_io);
 
     s->real_vram_size =
         (s->device_id == CIRRUS_ID_CLGD5446) ? 4096 * 1024 : 2048 * 1024;

hw/qxl.c

@@ -1910,6 +1910,7 @@ static int qxl_init_common(PCIQXLDevice *qxl)
     if (qxl->id == 0) {
         vga_dirty_log_start(&qxl->vga);
     }
+    memory_region_set_flush_coalesced(&qxl->io_bar);
 
 
     pci_register_bar(&qxl->pci, QXL_IO_RANGE_INDEX,

hw/vga-isa-mm.c

@@ -107,6 +107,7 @@ static void vga_mm_init(ISAVGAMMState *s, target_phys_addr_t vram_base,
     s_ioport_ctrl = g_malloc(sizeof(*s_ioport_ctrl));
     memory_region_init_io(s_ioport_ctrl, &vga_mm_ctrl_ops, s,
                           "vga-mm-ctrl", 0x100000);
+    memory_region_set_flush_coalesced(s_ioport_ctrl);
 
     vga_io_memory = g_malloc(sizeof(*vga_io_memory));
     /* XXX: endianness? */

hw/vga.c

@@ -361,6 +361,8 @@ uint32_t vga_ioport_read(void *opaque, uint32_t addr)
     VGACommonState *s = opaque;
     int val, index;
 
+    qemu_flush_coalesced_mmio_buffer();
+
     if (vga_ioport_invalid(s, addr)) {
         val = 0xff;
     } else {
@@ -453,6 +455,8 @@ void vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
     VGACommonState *s = opaque;
     int index;
 
+    qemu_flush_coalesced_mmio_buffer();
+
     /* check port range access depending on color/monochrome mode */
     if (vga_ioport_invalid(s, addr)) {
         return;
@@ -2338,6 +2342,7 @@ MemoryRegion *vga_init_io(VGACommonState *s,
     vga_mem = g_malloc(sizeof(*vga_mem));
     memory_region_init_io(vga_mem, &vga_mem_ops, s,
                           "vga-lowmem", 0x20000);
+    memory_region_set_flush_coalesced(vga_mem);
 
     return vga_mem;
 }

hw/vmware_vga.c

@@ -1186,6 +1186,7 @@ static int pci_vmsvga_initfn(PCIDevice *dev)
 
     memory_region_init_io(&s->io_bar, &vmsvga_io_ops, &s->chip,
                           "vmsvga-io", 0x10);
+    memory_region_set_flush_coalesced(&s->io_bar);
     pci_register_bar(&s->card, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io_bar);
 
     vmsvga_init(&s->chip, pci_address_space(dev),