[V2] LEON3: Add emulation of AMBA plug&play

From: Jiri Gaisler <jiri@gaisler.se>

AMBA plug&play is used by kernels to probe available devices (Timers,
UART, etc...). This is a static declaration of devices implemented in
QEMU. In the future, a more advanced version could compute those
information directly from the device tree.

Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
---

V2:
 - AHB and APB PNP are now grouped in one device
 - Initialisation moved to .instance_init
 - Minor fixes

 hw/sparc/Makefile.objs   |    1 +
 hw/sparc/grlib_ambapnp.c |  149 ++++++++++++++++++++++++++++++++++++++++++++++
 hw/sparc/leon3.c         |    3 +
 include/hw/sparc/grlib.h |   22 +++++++
 4 files changed, 175 insertions(+)
 create mode 100644 hw/sparc/grlib_ambapnp.c

I am a bit against the merge of AHB and APB initialization into
the same function. A grlib system can have any number of AHB and APB
buses, so there really should be a separate init routine per bus
as in the original patch.

Jiri.

On 10/09/2014 01:05 PM, Fabien Chouteau wrote:
> From: Jiri Gaisler <jiri@gaisler.se>
> 
> AMBA plug&play is used by kernels to probe available devices (Timers,
> UART, etc...). This is a static declaration of devices implemented in
> QEMU. In the future, a more advanced version could compute those
> information directly from the device tree.
> 
> Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
> ---
> 
> V2:
>  - AHB and APB PNP are now grouped in one device
>  - Initialisation moved to .instance_init
>  - Minor fixes
> 
>  hw/sparc/Makefile.objs   |    1 +
>  hw/sparc/grlib_ambapnp.c |  149 ++++++++++++++++++++++++++++++++++++++++++++++
>  hw/sparc/leon3.c         |    3 +
>  include/hw/sparc/grlib.h |   22 +++++++
>  4 files changed, 175 insertions(+)
>  create mode 100644 hw/sparc/grlib_ambapnp.c
> 
> diff --git a/hw/sparc/Makefile.objs b/hw/sparc/Makefile.objs
> index c987b5b..e763701 100644
> --- a/hw/sparc/Makefile.objs
> +++ b/hw/sparc/Makefile.objs
> @@ -1 +1,2 @@
>  obj-y += sun4m.o leon3.o
> +obj-$(CONFIG_GRLIB) += grlib_ambapnp.o
> diff --git a/hw/sparc/grlib_ambapnp.c b/hw/sparc/grlib_ambapnp.c
> new file mode 100644
> index 0000000..dd53004
> --- /dev/null
> +++ b/hw/sparc/grlib_ambapnp.c
> @@ -0,0 +1,149 @@
> +/*
> + * QEMU GRLIB AMBA Plug&Play Emulator
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> + * THE SOFTWARE.
> + */
> +
> +#include "hw/sysbus.h"
> +#include "hw/sparc/grlib.h"
> +
> +/* Size of memory mapped registers */
> +#define APBPNP_REG_SIZE (4096 - 8)
> +#define AHBPNP_REG_SIZE 4096
> +
> +#define GRLIB_AMBA_PNP(obj) \
> +    OBJECT_CHECK(AMBAPNP, (obj), TYPE_GRLIB_AMBA_PNP)
> +
> +typedef struct AMBAPNP {
> +    SysBusDevice parent_obj;
> +    MemoryRegion ahb_iomem;
> +    MemoryRegion apb_iomem;
> +} AMBAPNP;
> +
> +/* APB PNP */
> +
> +static uint64_t grlib_apbpnp_read(void *opaque, hwaddr addr,
> +                                   unsigned size)
> +{
> +    uint64_t read_data;
> +    addr &= 0xfff;
> +
> +    /* Unit registers */
> +    switch (addr & 0xffc) {
> +    case 0x00:
> +        read_data = 0x0400f000; /* Memory controller */
> +        break;
> +    case 0x04:
> +        read_data = 0x0000fff1;
> +        break;
> +    case 0x08:
> +        read_data = 0x0100c023; /* APBUART */
> +        break;
> +    case 0x0C:
> +        read_data = 0x0010fff1;
> +        break;
> +    case 0x10:
> +        read_data = 0x0100d040; /* IRQMP */
> +        break;
> +    case 0x14:
> +        read_data = 0x0020fff1;
> +        break;
> +    case 0x18:
> +        read_data = 0x01011006; /* GPTIMER */
> +        break;
> +    case 0x1C:
> +        read_data = 0x0030fff1;
> +        break;
> +
> +    default:
> +        read_data = 0;
> +    }
> +    if (size == 1) {
> +        read_data >>= (24 - (addr & 3) * 8);
> +        read_data &= 0x0ff;
> +    }
> +    return read_data;
> +}
> +
> +static const MemoryRegionOps grlib_apbpnp_ops = {
> +    .read       = grlib_apbpnp_read,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +};
> +
> +/* AHB PNP */
> +
> +static uint64_t grlib_ahbpnp_read(void *opaque, hwaddr addr,
> +                                   unsigned size)
> +{
> +    addr &= 0xffc;
> +
> +    /* Unit registers */
> +    switch (addr) {
> +    case 0:
> +        return 0x01003000;      /* LEON3 */
> +    case 0x800:
> +        return 0x0400f000;      /* Memory controller  */
> +    case 0x810:
> +        return 0x0003e002;
> +    case 0x814:
> +        return 0x2000e002;
> +    case 0x818:
> +        return 0x4003c002;
> +    case 0x820:
> +        return 0x01006000;      /* APB bridge @ 0x80000000 */
> +    case 0x830:
> +        return 0x8000fff2;
> +
> +    default:
> +        return 0;
> +    }
> +}
> +
> +static const MemoryRegionOps grlib_ahbpnp_ops = {
> +    .read = grlib_ahbpnp_read,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +};
> +
> +static void grlib_ambapnp_init(Object *obj)
> +{
> +    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
> +    AMBAPNP *pnp = GRLIB_AMBA_PNP(obj);
> +
> +    memory_region_init_io(&pnp->ahb_iomem, OBJECT(pnp), &grlib_ahbpnp_ops, pnp,
> +                          "ahbpnp", AHBPNP_REG_SIZE);
> +    sysbus_init_mmio(sbd, &pnp->ahb_iomem);
> +
> +    memory_region_init_io(&pnp->apb_iomem, OBJECT(pnp), &grlib_apbpnp_ops, pnp,
> +                          "apbpnp", APBPNP_REG_SIZE);
> +    sysbus_init_mmio(sbd, &pnp->apb_iomem);
> +}
> +
> +static const TypeInfo grlib_ambapnp_info = {
> +    .name          = TYPE_GRLIB_AMBA_PNP,
> +    .parent        = TYPE_SYS_BUS_DEVICE,
> +    .instance_size = sizeof(AMBAPNP),
> +    .instance_init = grlib_ambapnp_init,
> +};
> +
> +static void grlib_ambapnp_register_types(void)
> +{
> +    type_register_static(&grlib_ambapnp_info);
> +}
> +
> +type_init(grlib_ambapnp_register_types)
> diff --git a/hw/sparc/leon3.c b/hw/sparc/leon3.c
> index 751392e..2962539 100644
> --- a/hw/sparc/leon3.c
> +++ b/hw/sparc/leon3.c
> @@ -207,6 +207,9 @@ static void leon3_generic_hw_init(MachineState *machine)
>          }
>      }
>  
> +    /* Allocate AHB/APB PNP */
> +    grlib_ambapnp_create(0xFFFFF000 /* AHB */, 0x800FF000 /* APB */);
> +
>      /* Allocate timers */
>      grlib_gptimer_create(0x80000300, 2, CPU_CLK, cpu_irqs, 6);
>  
> diff --git a/include/hw/sparc/grlib.h b/include/hw/sparc/grlib.h
> index 470ce72..5c098df 100644
> --- a/include/hw/sparc/grlib.h
> +++ b/include/hw/sparc/grlib.h
> @@ -123,4 +123,26 @@ DeviceState *grlib_apbuart_create(hwaddr  base,
>      return dev;
>  }
>  
> +
> +/* AMBA PNP */
> +
> +#define TYPE_GRLIB_AMBA_PNP "grlib,ambapnp"
> +
> +static inline
> +DeviceState *grlib_ambapnp_create(hwaddr ahbpnp_base, hwaddr apbpnp_base)
> +{
> +    DeviceState *dev;
> +
> +    dev = qdev_create(NULL, TYPE_GRLIB_AMBA_PNP);
> +
> +    if (qdev_init(dev)) {
> +        return NULL;
> +    }
> +
> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, ahbpnp_base);
> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 1, apbpnp_base);
> +
> +    return dev;
> +}
> +
>  #endif /* ! _GRLIB_H_ */
>

On 10/09/2014 05:32 PM, Jiri Gaisler wrote:
> 
> I am a bit against the merge of AHB and APB initialization into
> the same function. A grlib system can have any number of AHB and APB
> buses, so there really should be a separate init routine per bus
> as in the original patch.
> 

I understand your concerns, for the moment the system definition of
leon3 is very static, and I don't see that we will need more flexibility
in the near future. In that case I think it's better to not add
unnecessary complexity in the code.