Re: [PATCH v2 3/4] hw/display/vga-mmio: QOM'ify vga_mmio_init() as TYPE_VGA_MMIO

[Philippe Mathieu-Daudé]

On 12/13/21 11:48, Thomas Huth wrote:
> On 06/12/2021 23.45, Philippe Mathieu-Daudé wrote:
>> Introduce TYPE_VGA_MMIO, a sysbus device.
>>
>> While there is no change in the vga_mmio_init()
>> interface, this is a migration compatibility break
>> of the MIPS Acer Pica 61 Jazz machine (pica61).
> 
> It's unfortunate, but as far as I know, it would be pretty difficult or
> even impossible to get this done without versioned machine types? So
> IMHO it's ok to break this in this case here.

Hervé and Zoltan were already Cc'ed, adding Mark and Finn;
I am not sure who else would be annoyed by that change.

>> Suggested-by: Thomas Huth <thuth@redhat.com>
>> Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>> ---
>>   include/hw/display/vga.h |   2 +
>>   hw/display/vga-mmio.c    | 132 +++++++++++++++++++++++++++------------
>>   2 files changed, 94 insertions(+), 40 deletions(-)
>>
>> diff --git a/include/hw/display/vga.h b/include/hw/display/vga.h
>> index c16a5c26dae..98b2e560f9b 100644
>> --- a/include/hw/display/vga.h
>> +++ b/include/hw/display/vga.h
>> @@ -24,6 +24,8 @@ enum vga_retrace_method {
>>     extern enum vga_retrace_method vga_retrace_method;
>>   +#define TYPE_VGA_MMIO "vga-mmio"
>> +
>>   int vga_mmio_init(hwaddr vram_base, hwaddr ctrl_base,
>>                     int it_shift, MemoryRegion *address_space);
>>   diff --git a/hw/display/vga-mmio.c b/hw/display/vga-mmio.c
>> index 5671fdb920f..10bde32af5c 100644
>> --- a/hw/display/vga-mmio.c
>> +++ b/hw/display/vga-mmio.c
>> @@ -23,21 +23,34 @@
>>    */
>>     #include "qemu/osdep.h"
>> -#include "qemu/bitops.h"
>> -#include "qemu/units.h"
>> -#include "migration/vmstate.h"
>> +#include "qapi/error.h"
>>   #include "hw/display/vga.h"
>> +#include "hw/sysbus.h"
>> +#include "hw/display/vga.h"
>> +#include "hw/qdev-properties.h"
>>   #include "vga_int.h"
>> -#include "ui/pixel_ops.h"
>>   -#define VGA_RAM_SIZE (8 * MiB)
>> +/*
>> + * QEMU interface:
>> + *  + sysbus MMIO region 0: VGA I/O registers
>> + *  + sysbus MMIO region 1: VGA MMIO registers
>> + *  + sysbus MMIO region 2: VGA memory
>> + */
>>   -typedef struct VGAMmioState {
>> +OBJECT_DECLARE_SIMPLE_TYPE(VGAMmioState, VGA_MMIO)
>> +
>> +struct VGAMmioState {
>> +    /*< private >*/
>> +    SysBusDevice parent_obj;
>> +
>> +    /*< public >*/
>>       VGACommonState vga;
>> -    int it_shift;
>> -} VGAMmioState;
>> +    MemoryRegion iomem;
>> +    MemoryRegion lowmem;
>> +
>> +    uint8_t it_shift;
>> +};
>>   -/* Memory mapped interface */
>>   static uint64_t vga_mm_read(void *opaque, hwaddr addr, unsigned size)
>>   {
>>       VGAMmioState *s = opaque;
>> @@ -65,42 +78,81 @@ static const MemoryRegionOps vga_mm_ctrl_ops = {
>>       .endianness = DEVICE_NATIVE_ENDIAN,
>>   };
>>   +static void vga_mmio_reset(DeviceState *dev)
>> +{
>> +    VGAMmioState *s = VGA_MMIO(dev);
>> +
>> +    vga_common_reset(&s->vga);
>> +}
>> +
>>   int vga_mmio_init(hwaddr vram_base, hwaddr ctrl_base,
>>                     int it_shift, MemoryRegion *address_space)
>>   {
>> -    VGAMmioState *s;
>> -    MemoryRegion *s_ioport_ctrl, *vga_io_memory;
>> +    DeviceState *dev;
>> +    SysBusDevice *s;
>>   -    s = g_malloc0(sizeof(*s));
>> +    dev = qdev_new(TYPE_VGA_MMIO);
>> +    qdev_prop_set_uint8(dev, "it_shift", it_shift);
>> +    s = SYS_BUS_DEVICE(dev);
>> +    sysbus_realize_and_unref(s, &error_fatal);
>>   -    s->vga.vram_size_mb = VGA_RAM_SIZE / MiB;
>> -    s->vga.global_vmstate = true;
>> -    vga_common_init(&s->vga, NULL);
>> -
>> -    s->it_shift = it_shift;
>> -    s_ioport_ctrl = g_malloc(sizeof(*s_ioport_ctrl));
>> -    memory_region_init_io(s_ioport_ctrl, NULL, &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? */
>> -    memory_region_init_io(vga_io_memory, NULL, &vga_mem_ops, &s->vga,
>> -                          "vga-mem", 0x20000);
>> -
>> -    vmstate_register(NULL, 0, &vmstate_vga_common, s);
>> -
>> -    memory_region_add_subregion(address_space, ctrl_base,
>> s_ioport_ctrl);
>> -    s->vga.bank_offset = 0;
>> -    memory_region_add_subregion(address_space,
>> -                                vram_base + 0x000a0000, vga_io_memory);
>> -    memory_region_set_coalescing(vga_io_memory);
>> -
>> -    s->vga.con = graphic_console_init(NULL, 0, s->vga.hw_ops, s);
>> -
>> -    memory_region_add_subregion(address_space,
>> -                                VBE_DISPI_LFB_PHYSICAL_ADDRESS,
>> -                                &s->vga.vram);
>> +    sysbus_mmio_map(s, 0, ctrl_base);
>> +    sysbus_mmio_map(s, 1, vram_base + 0x000a0000);
>> +    sysbus_mmio_map(s, 2, VBE_DISPI_LFB_PHYSICAL_ADDRESS);
>>         return 0;
>>   }
>> +
>> +static void vga_mmio_realizefn(DeviceState *dev, Error **errp)
>> +{
>> +    VGAMmioState *s = VGA_MMIO(dev);
>> +    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
>> +
>> +    memory_region_init_io(&s->iomem, OBJECT(dev), &vga_mm_ctrl_ops, s,
>> +                          "vga-mmio", 0x100000);
>> +    memory_region_set_flush_coalesced(&s->iomem);
>> +    sysbus_init_mmio(sbd, &s->iomem);
>> +
>> +    /* XXX: endianness? */
>> +    memory_region_init_io(&s->lowmem, OBJECT(dev), &vga_mem_ops,
>> &s->vga,
>> +                          "vga-lowmem", 0x20000);
>> +    memory_region_set_coalescing(&s->lowmem);
>> +    sysbus_init_mmio(sbd, &s->lowmem);
>> +
>> +    s->vga.bank_offset = 0;
>> +    s->vga.global_vmstate = true;
>> +    vga_common_init(&s->vga, OBJECT(dev));
>> +    sysbus_init_mmio(sbd, &s->vga.vram);
>> +    s->vga.con = graphic_console_init(dev, 0, s->vga.hw_ops, &s->vga);
>> +}
>> +
>> +static Property vga_mmio_properties[] = {
>> +    DEFINE_PROP_UINT8("it_shift", VGAMmioState, it_shift, 0),
>> +    DEFINE_PROP_UINT32("vgamem_mb", VGAMmioState, vga.vram_size_mb, 8),
>> +    DEFINE_PROP_END_OF_LIST(),
>> +};
>> +
>> +static void vga_mmio_class_initfn(ObjectClass *klass, void *data)
> 
> Just a matter of taste, but I'd prefer "oc" instead of "klass".
> 
> Anyway:
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> 
>