Re: [PATCH v5 7/8] hw/arm/sysbus-fdt: enable amd-xgbe dynamic instantiation

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

Hi Peter,
On 01/25/2016 03:33 PM, Peter Maydell wrote:
> On 18 January 2016 at 15:16, Eric Auger <eric.auger@linaro.org> wrote:
>> This patch allows the instantiation of the vfio-amd-xgbe device
>> from the QEMU command line (-device vfio-amd-xgbe,host="<device>").
>>
>> The guest is exposed with a device tree node that combines the description
>> of both XGBE and PHY (representation supported from 4.2 onwards kernel):
>> Documentation/devicetree/bindings/net/amd-xgbe.txt.
>>
>> There are 5 register regions, 6 interrupts including 4 optional
>> edge-sensitive per-channel interrupts.
>>
>> Some property values are inherited from host device tree. Host device tree
>> must feature a combined XGBE/PHY representation (>= 4.2 host kernel).
>>
>> 2 clock nodes (dma and ptp) also are created. It is checked those clocks
>> are fixed on host side.
>>
>> AMD XGBE node creation function has a dependency on vfio Linux header and
>> more generally node creation function for VFIO platform devices only make
>> sense with CONFIG_LINUX so let's protect this code with #ifdef CONFIG_LINUX.
>>
>> Signed-off-by: Eric Auger <eric.auger@linaro.org>
> 
>>  hw/arm/sysbus-fdt.c | 195 ++++++++++++++++++++++++++++++++++++++++++++++++++--
>>  1 file changed, 189 insertions(+), 6 deletions(-)
> 
> I'll let it pass for this patchset, but this file is starting to
> get big, and probably needs some kind of split into common functions
> in one file and then a separate file for each pass-through device,
> if they're all going to require 200-odd lines to deal with.

That's understood. If you don't mind i would rather introduce that move
in a separate series then.

Thanks

Eric
> 
>> +/**
>> + * sysfs_to_dt_name: convert the name found in sysfs into the node name
>> + * for instance e0900000.xgmac is converted into xgmac@e0900000
>> + * @sysfs_name: directory name in sysfs
>> + *
>> + * returns the device tree name upon success or NULL in case the sysfs name
>> + * does not match the expected format
>> + */
>> +static char *sysfs_to_dt_name(const char *sysfs_name)
>> +{
>> +    gchar **substrings =  g_strsplit(sysfs_name, ".", 2);
>> +    char *dt_name = NULL;
>> +
>> +    if (!substrings || !substrings[1] || !substrings[0]) {
> 
> We should check substrings[0] before substrings[1], as otherwise
> if we're passed the empty string we'll index off the end of the
> vector.
> 
>> +        goto out;
>> +    }
>> +    dt_name = g_strdup_printf("%s@%s", substrings[1], substrings[0]);
>> +out:
>> +    g_strfreev(substrings);
>> +    return dt_name;
>> +}
>> +
>>  /* Device Specific Code */
>>
>>  /**
>> @@ -243,9 +269,166 @@ fail_reg:
>>      return ret;
>>  }
>>
>> +
>> +/* AMD xgbe properties whose values are copied/pasted from host */
>> +static HostProperty amd_xgbe_copied_properties[] = {
>> +    {"compatible", false},
>> +    {"dma-coherent", true},
>> +    {"amd,per-channel-interrupt", true},
>> +    {"phy-mode", false},
>> +    {"mac-address", true},
>> +    {"amd,speed-set", false},
>> +    {"amd,serdes-blwc", true},
>> +    {"amd,serdes-cdr-rate", true},
>> +    {"amd,serdes-pq-skew", true},
>> +    {"amd,serdes-tx-amp", true},
>> +    {"amd,serdes-dfe-tap-config", true},
>> +    {"amd,serdes-dfe-tap-enable", true},
>> +    {"clock-names", false},
>> +};
>> +
>> +/**
>> + * add_amd_xgbe_fdt_node
>> + *
>> + * Generates the combined xgbe/phy node following kernel >=4.2
>> + * binding documentation:
>> + * Documentation/devicetree/bindings/net/amd-xgbe.txt:
>> + * Also 2 clock nodes are created (dma and ptp)
>> + *
>> + * self-asserts in case of error
> 
> "asserts".
> 
>> +    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(GIC_FDT_IRQ_TYPE_SPI);
>> +        irq_attr[3 * i + 1] = cpu_to_be32(irq_number);
>> +        /*
>> +          * General device interrupt and PCS auto-negociation interrupts are
> 
> "negotiation"
> 
>> +          * level-sensitive while the 4 per-channel interrupts are edge
>> +          * sensitive
>> +          */
>> +        QLIST_FOREACH(intp, &vdev->intp_list, next) {
>> +            if (intp->pin == i) {
>> +                break;
>> +            }
>> +        }
>> +        if (intp->flags & VFIO_IRQ_INFO_AUTOMASKED) {
>> +            irq_attr[3 * i + 2] = cpu_to_be32(GIC_FDT_IRQ_FLAGS_LEVEL_HI);
>> +        } else {
>> +            irq_attr[3 * i + 2] = cpu_to_be32(GIC_FDT_IRQ_FLAGS_EDGE_LO_HI);
>> +        }
>> +    }
>> +    qemu_fdt_setprop(guest_fdt, nodename, "interrupts",
>> +                     irq_attr, vbasedev->num_irqs * 3 * sizeof(uint32_t));
>> +
>> +    g_free(host_fdt);
>> +    g_strfreev(node_path);
>> +    g_free(irq_attr);
>> +    g_free(reg_attr);
>> +    g_free(nodename);
>> +    return 0;
>> +}
>> +
>> +#endif /* CONFIG_LINUX */
>> +
>>  /* list of supported dynamic sysbus devices */
>>  static const NodeCreationPair add_fdt_node_functions[] = {
>> +#ifdef CONFIG_LINUX
>>      {TYPE_VFIO_CALXEDA_XGMAC, add_calxeda_midway_xgmac_fdt_node},
>> +    {TYPE_VFIO_AMD_XGBE, add_amd_xgbe_fdt_node},
>> +#endif
>>      {"", NULL}, /* last element */
>>  };
> 
> thanks
> -- PMM
>