Re: [Qemu-devel] [RESEND PATCH v16 1/6] hw/arm/sysbus-fdt: enable vfio-calxeda-xgmac dynamic instantiation

[Peter Maydell <peter.maydell@linaro.org>]

On 15 June 2015 at 17:33, Eric Auger <eric.auger@linaro.org> wrote:
> This patch allows the instantiation of the vfio-calxeda-xgmac device
> from the QEMU command line (-device vfio-calxeda-xgmac,host="<device>").
>
> A specialized device tree node is created for the guest, containing
> compat, dma-coherent, reg and interrupts properties.
>
> Signed-off-by: Eric Auger <eric.auger@linaro.org>
>

Minor nits:

> +/* Device Specific Code */
> +
> +/**
> + * add_calxeda_midway_xgmac_fdt_node
> + *
> + * Generates a simple node with following properties:
> + * compatible string, regs, interrupts, dma-coherent
> + */
> +static int add_calxeda_midway_xgmac_fdt_node(SysBusDevice *sbdev, void *opaque)
> +{
> +    PlatformBusFDTData *data = opaque;
> +    PlatformBusDevice *pbus = data->pbus;
> +    void *fdt = data->fdt;
> +    const char *parent_node = data->pbus_node_name;
> +    int compat_str_len, i, ret = -1;
> +    char *nodename;
> +    uint32_t *irq_attr, *reg_attr;
> +    uint64_t mmio_base, irq_number;
> +    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
> +    VFIODevice *vbasedev = &vdev->vbasedev;
> +
> +    mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
> +    nodename = g_strdup_printf("%s/%s@%" PRIx64, parent_node,
> +                               vbasedev->name, mmio_base);
> +    qemu_fdt_add_subnode(fdt, nodename);
> +
> +    compat_str_len = strlen(vdev->compat) + 1;
> +    qemu_fdt_setprop(fdt, nodename, "compatible",
> +                          vdev->compat, compat_str_len);
> +
> +    qemu_fdt_setprop(fdt, nodename, "dma-coherent", "", 0);
> +
> +    reg_attr = g_new(uint32_t, vbasedev->num_regions*2);

You should have spaces around the '*' operator here (and in a
couple of other places below).

> +    for (i = 0; i < vbasedev->num_regions; i++) {
> +        mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, i);
> +        reg_attr[2*i] = cpu_to_be32(mmio_base);
> +        reg_attr[2*i+1] = cpu_to_be32(
> +                                memory_region_size(&vdev->regions[i]->mem));
> +    }
> +    ret = qemu_fdt_setprop(fdt, nodename, "reg", reg_attr,
> +                           vbasedev->num_regions*2*sizeof(uint32_t));
> +    if (ret) {
> +        error_report("could not set reg property of node %s", nodename);
> +        goto fail_reg;
> +    }
> +
> +    irq_attr = g_new(uint32_t, vbasedev->num_irqs*3);
> +    for (i = 0; i < vbasedev->num_irqs; i++) {
> +        irq_number = platform_bus_get_irqn(pbus, sbdev , i)
> +                         + data->irq_start;
> +        irq_attr[3*i] = cpu_to_be32(0);
> +        irq_attr[3*i+1] = cpu_to_be32(irq_number);
> +        irq_attr[3*i+2] = cpu_to_be32(0x4);

In virt.c the magic numbers in cells 0 and 2 have #defines
(GIC_FDT_IRQ_TYPE_SPI and GIC_FDT_IRQ_FLAGS_LEVEL_HI).

(1) maybe we should pull those out into a header so you can use them here
(2) is this device really using a level-triggered interrupt?

> +    }
> +   ret = qemu_fdt_setprop(fdt, nodename, "interrupts",
> +                     irq_attr, vbasedev->num_irqs*3*sizeof(uint32_t));
> +    if (ret) {
> +        error_report("could not set interrupts property of node %s",
> +                     nodename);
> +    }
> +    g_free(irq_attr);
> +fail_reg:
> +    g_free(reg_attr);
> +    g_free(nodename);
> +    return ret;
> +}
> +
>  /* list of supported dynamic sysbus devices */
>  static const NodeCreationPair add_fdt_node_functions[] = {
> +    {TYPE_VFIO_CALXEDA_XGMAC, add_calxeda_midway_xgmac_fdt_node},
>      {"", NULL}, /* last element */
>  };

This file could get big if we have a lot of platform passthrough
devices, but let's hope we don't...

Otherwise:
Acked-by: Peter Maydell <peter.maydell@linaro.org>

-- PMM