Re: [Qemu-devel] [PATCH 08/17] isa: add an ISA DMA interface, and store it within the ISA bus

[John Snow]

On 12/29/2015 03:04 AM, Hervé Poussineau wrote:
> This will permit to deprecate global DMA_*() functions.
> 
> Signed-off-by: Hervé Poussineau <address@hidden>
> ---
>  hw/isa/isa-bus.c        | 21 +++++++++++++++++++++
>  include/hw/isa/isa.h    | 38 ++++++++++++++++++++++++++++++++++++++
>  include/qemu/typedefs.h |  1 +
>  3 files changed, 60 insertions(+)
> 
> diff --git a/hw/isa/isa-bus.c b/hw/isa/isa-bus.c
> index 43e0cd8..8887433 100644
> --- a/hw/isa/isa-bus.c
> +++ b/hw/isa/isa-bus.c
> @@ -36,6 +36,12 @@ static void isa_bus_class_init(ObjectClass *klass, void 
> *data)
>      k->get_fw_dev_path = isabus_get_fw_dev_path;
>  }
>  
> +static const TypeInfo isa_dma_info = {
> +    .name = TYPE_ISADMA,
> +    .parent = TYPE_INTERFACE,
> +    .class_size = sizeof(IsaDmaClass),
> +};
> +
>  static const TypeInfo isa_bus_info = {
>      .name = TYPE_ISA_BUS,
>      .parent = TYPE_BUS,
> @@ -92,6 +98,20 @@ void isa_init_irq(ISADevice *dev, qemu_irq *p, int isairq)
>      dev->nirqs++;
>  }
>  
> +void isa_bus_dma(ISABus *bus, IsaDma *dma8, IsaDma *dma16)
> +{
> +    assert(bus && dma8 && dma16);
> +    assert(!bus->dma[0] && !bus->dma[1]);
> +    bus->dma[0] = dma8;
> +    bus->dma[1] = dma16;
> +}
> +
> +IsaDma *isa_get_dma(ISABus *bus, int nchan)
> +{
> +    assert(bus);
> +    return bus->dma[nchan > 3 ? 1 : 0];
> +}
> +
>  static inline void isa_init_ioport(ISADevice *dev, uint16_t ioport)
>  {
>      if (dev && (dev->ioport_id == 0 || ioport < dev->ioport_id)) {
> @@ -233,6 +253,7 @@ static const TypeInfo isa_device_type_info = {
>  
>  static void isabus_register_types(void)
>  {
> +    type_register_static(&isa_dma_info);
>      type_register_static(&isa_bus_info);
>      type_register_static(&isabus_bridge_info);
>      type_register_static(&isa_device_type_info);
> diff --git a/include/hw/isa/isa.h b/include/hw/isa/isa.h
> index d84852b..193ceb2 100644
> --- a/include/hw/isa/isa.h
> +++ b/include/hw/isa/isa.h
> @@ -34,6 +34,41 @@ static inline uint16_t applesmc_port(void)
>      return 0;
>  }
>  
> +#define TYPE_ISADMA "isa-dma"
> +
> +#define ISADMA_CLASS(klass) \
> +    OBJECT_CLASS_CHECK(IsaDmaClass, (klass), TYPE_ISADMA)
> +#define ISADMA_GET_CLASS(obj) \
> +    OBJECT_GET_CLASS(IsaDmaClass, (obj), TYPE_ISADMA)
> +#define ISADMA(obj) \
> +    INTERFACE_CHECK(IsaDma, (obj), TYPE_ISADMA)
> +
> +typedef struct IsaDma {
> +    Object parent;
> +} IsaDma;
> +

You define IsaDma here, and

> +typedef enum {
> +    ISADMA_TRANSFER_VERIFY,
> +    ISADMA_TRANSFER_READ,
> +    ISADMA_TRANSFER_WRITE,
> +    ISADMA_TRANSFER_ILLEGAL,
> +} IsaDmaTransferMode;
> +
> +typedef struct IsaDmaClass {
> +    InterfaceClass parent;
> +
> +    IsaDmaTransferMode (*get_transfer_mode)(IsaDma *obj, int nchan);
> +    bool (*has_autoinitialization)(IsaDma *obj, int nchan);
> +    int (*read_memory)(IsaDma *obj, int nchan, void *buf, int pos, int len);
> +    int (*write_memory)(IsaDma *obj, int nchan, void *buf, int pos, int len);
> +    void (*hold_DREQ)(IsaDma *obj, int nchan);
> +    void (*release_DREQ)(IsaDma *obj, int nchan);
> +    void (*schedule)(IsaDma *obj);
> +    void (*register_channel)(IsaDma *obj, int nchan,
> +                             DMA_transfer_handler transfer_handler,
> +                             void *opaque);
> +} IsaDmaClass;
> +
>  typedef struct ISADeviceClass {
>      DeviceClass parent_class;
>  } ISADeviceClass;
> @@ -46,6 +81,7 @@ struct ISABus {
>      MemoryRegion *address_space;
>      MemoryRegion *address_space_io;
>      qemu_irq *irqs;
> +    IsaDma *dma[2];
>  };
>  
>  struct ISADevice {
> @@ -63,6 +99,8 @@ ISABus *isa_bus_new(DeviceState *dev, MemoryRegion 
> *address_space,
>  void isa_bus_irqs(ISABus *bus, qemu_irq *irqs);
>  qemu_irq isa_get_irq(ISADevice *dev, int isairq);
>  void isa_init_irq(ISADevice *dev, qemu_irq *p, int isairq);
> +void isa_bus_dma(ISABus *bus, IsaDma *dma8, IsaDma *dma16);
> +IsaDma *isa_get_dma(ISABus *bus, int nchan);
>  MemoryRegion *isa_address_space(ISADevice *dev);
>  MemoryRegion *isa_address_space_io(ISADevice *dev);
>  ISADevice *isa_create(ISABus *bus, const char *name);
> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
> index 78fe6e8..6ed91b4 100644
> --- a/include/qemu/typedefs.h
> +++ b/include/qemu/typedefs.h
> @@ -33,6 +33,7 @@ typedef struct I2CBus I2CBus;
>  typedef struct I2SCodec I2SCodec;
>  typedef struct ISABus ISABus;
>  typedef struct ISADevice ISADevice;
> +typedef struct IsaDma IsaDma;

again here. Clang gets a little whiny about that.

>  typedef struct LoadStateEntry LoadStateEntry;
>  typedef struct MACAddr MACAddr;
>  typedef struct MachineClass MachineClass;
> 

-- 
—js