Re: [Qemu-devel] [RFC PATCH 4/4] hw/arm/sysbus-fdt: arm, pl330 vfio device property

[Eric Auger <eric.auger@linaro.org>]

Hi Baptiste,
On 01/12/2015 02:21 PM, Baptiste Reynal wrote:
> Adapt arm,pl330 function to use the vfio device property API.
> 
> Clock apb-pclk is the default if a clock is needed by the device.
> 
> Three optional parameters are taken into account :
> - #dma-cells
> - #dma-channels
> - #dma-requests
> 
> Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
> ---
>  hw/arm/sysbus-fdt.c | 120 ++++++++++++++++++++++++++++++++++++++++++++--------
>  1 file changed, 103 insertions(+), 17 deletions(-)
> 
> diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c
> index 087e788..a0adc50 100644
> --- a/hw/arm/sysbus-fdt.c
> +++ b/hw/arm/sysbus-fdt.c
> @@ -96,13 +96,13 @@ static int set_interrupts_fdt_node(char *nodename, SysBusDevice *sbdev,
>          irq_attr[3*i+2] = cpu_to_be32(((__u32 *) irq_prop->data)[3*i+2]);
>      }
>  
> -    ret = qemu_fdt_setprop(fdt, nodename, "interrupts",
> -            irq_attr, vbasedev->num_irqs*3*sizeof(uint32_t));
> +   ret = qemu_fdt_setprop(fdt, nodename, "interrupts",
> +                     irq_attr, vbasedev->num_irqs*3*sizeof(uint32_t));
delta may be removed
>  
>      g_free(irq_attr);
>      g_free(irq_prop);
>  
> -    return ret;
> +   return ret;
delta may be removed
>  }
>  
>  /**
> @@ -140,6 +140,54 @@ static int set_regions_fdt_node(char *nodename, SysBusDevice *sbdev,
>      return ret;
>  }
>  
may deserve a comment and/or pointer to
Documentation/devicetree/bindings/arm/primecell.txt; don't know whether
this is the reference doc, sorry.
> +static int set_arm_primecell_node(char *nodename, SysBusDevice *sbdev, void
> +        *opaque)
> +{
> +    PlatformBusFdtData *data = opaque;
> +    void *fdt = data->fdt;
> +    int ret;
> +    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
> +    VFIODevice *vbasedev = &vdev->vbasedev;
> +    struct vfio_dev_property *property;
> +
Wouldn't it make sense to handle the required compatible prop here?
> +    /* Optional properties */
> +    property = vfio_get_dev_property(vbasedev->fd, "interrupts",
> +            VFIO_DEV_PROPERTY_TYPE_U32);
> +    if (property != NULL) {
> +        ret = set_interrupts_fdt_node(nodename, sbdev, opaque);
> +        if (ret < 0) {
> +            error_report("could not set interrupts property of node %s",
> +                    nodename);
> +            goto fail;
in case of fail the property is not released.
> +        }
> +        g_free(property);
> +    }
> +
> +    property = vfio_get_dev_property(vbasedev->fd, "clock-names",
> +            VFIO_DEV_PROPERTY_TYPE_STRINGS);
> +    if (property != NULL) {
> +        /* If a clock is attached, we rely on apb-pclk */
> +        /* Check clock existence */
> +        ret = fdt_path_offset(fdt, "/apb-pclk");
> +
> +        if (ret < 0) {
> +            error_report("could not set clocks property of node %s", nodename);
> +            goto fail;
release property
> +        } else {
> +            qemu_fdt_setprop_cells(fdt, nodename, "clocks",
> +                    qemu_fdt_getprop_cell(fdt, "/apb-pclk", "phandle"));
> +            char clock_names[] = "apb_pclk";
> +            qemu_fdt_setprop(fdt, nodename, "clock-names", clock_names,
> +                    sizeof(clock_names));
> +        }
> +        g_free(property);
do you intend to support other optional properties?
> +    }
> +
> +    return 0;
> +
> +fail:
> +    return -1;
> +}
>  /**
>   * add_calxeda_midway_xgmac_fdt_node
>   *
> @@ -213,6 +261,8 @@ static int add_arm_pl330_fdt_node(SysBusDevice *sbdev, void *opaque)
>      VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
>      VFIODevice *vbasedev = &vdev->vbasedev;
>      Object *obj = OBJECT(sbdev);
> +    struct vfio_dev_property *property;
> +    int propint;
>  
>      mmio_base = object_property_get_int(obj, "mmio[0]", NULL);
>  
> @@ -222,6 +272,13 @@ static int add_arm_pl330_fdt_node(SysBusDevice *sbdev, void *opaque)
>  
>      qemu_fdt_add_subnode(fdt, nodename);
>  
> +    ret = set_arm_primecell_node(nodename, sbdev, opaque);
> +    if (ret < 0) {
> +        error_report("could not set arm,primecell properties of node %s",
> +                nodename);
> +        goto fail;
> +    }
> +
>      /*
>       * Process compatible string to deal with multiple strings
>       * (; is replaced by \0)
> @@ -237,20 +294,6 @@ static int add_arm_pl330_fdt_node(SysBusDevice *sbdev, void *opaque)
>      qemu_fdt_setprop(fdt, nodename, "compatible",
>                            compat, compat_str_len);
>  
> -    /* Setup clocks for AMBA device */
> -    /* Check clock existence */
> -    ret = fdt_path_offset(fdt, "/apb-pclk");
> -
> -    if (ret < 0) {
> -        error_report("could not set clocks property of node %s", nodename);
> -    } else {
> -        qemu_fdt_setprop_cells(fdt, nodename, "clocks",
> -                qemu_fdt_getprop_cell(fdt, "/apb-pclk", "phandle"));
> -        char clock_names[] = "apb_pclk";
> -        qemu_fdt_setprop(fdt, nodename, "clock-names", clock_names,
> -                sizeof(clock_names));
> -    }
> -
>      ret = set_regions_fdt_node(nodename, sbdev, opaque);
>  
>      if (ret < 0) {
> @@ -266,6 +309,49 @@ static int add_arm_pl330_fdt_node(SysBusDevice *sbdev, void *opaque)
>          goto fail;
>      }
>  
> +    /* Optional properties */
> +    property = vfio_get_dev_property(vbasedev->fd, "#dma-cells",
> +            VFIO_DEV_PROPERTY_TYPE_U32);
> +    if (property != NULL) {
> +        propint = cpu_to_be32(((__u32 *) property->data)[0]);
> +        ret = qemu_fdt_setprop(fdt, nodename, "#dma-cells", &propint,
> +                sizeof(int));
> +        if (ret < 0) {
> +            error_report("could not set #dma-cells property of node %s",
> +                    nodename);
> +            goto fail;
property release
> +        }
> +        g_free(property);
> +    }
> +
> +    property = vfio_get_dev_property(vbasedev->fd, "#dma-channels",
> +            VFIO_DEV_PROPERTY_TYPE_U32);
> +    if (property != NULL) {
> +        propint = cpu_to_be32(((__u32 *) property->data)[0]);
> +        ret = qemu_fdt_setprop(fdt, nodename, "#dma-cells", &propint,
> +                sizeof(int));
> +        if (ret < 0) {
> +            error_report("could not set #dma-cells property of node %s",
> +                    nodename);
> +            goto fail;
> +        }
> +        g_free(property);
> +    }
> +
> +    property = vfio_get_dev_property(vbasedev->fd, "#dma-requests",
> +            VFIO_DEV_PROPERTY_TYPE_U32);
> +    if (property != NULL) {
> +        propint = cpu_to_be32(((__u32 *) property->data)[0]);
> +        ret = qemu_fdt_setprop(fdt, nodename, "#dma-cells", &propint,
> +                sizeof(int));
> +        if (ret < 0) {
> +            error_report("could not set #dma-cells property of node %s",
> +                    nodename);
> +            goto fail;
> +        }
> +        g_free(property);
> +    }
> +
>      g_free(nodename);
>  
>      return 0;
to me it looks a good and interesting illustration of the modality

Best Regards

Eric
>