如何解释/ proc / bus / pci / devices的内容?

时间:2010-05-07 18:02:02

标签: linux pci-bus procfs

'cat / proc / bus / pci / devices'的前几个字段是可以理解的。

字段1 - BusDevFunc
字段2 - 供应商ID +设备ID
字段3 - 中断线
字段4 - BAR 0
其后BAR寄存器(0 - 5)之后。

打印出BAR寄存器后,其他字段是什么?具体来说,打印出哪个PCI配置空间寄存器(偏移)?

1 个答案:

答案 0 :(得分:15)

这是内核中的相应代码:

static int show_device(struct seq_file *m, void *v)
{
    const struct pci_dev *dev = v;
    const struct pci_driver *drv;
    int i;

    if (dev == NULL)
        return 0;

    drv = pci_dev_driver(dev);
    seq_printf(m, "%02x%02x\t%04x%04x\t%x",
            dev->bus->number,
            dev->devfn,
            dev->vendor,
            dev->device,
            dev->irq);
    /* Here should be 7 and not PCI_NUM_RESOURCES as we need to preserve compatibility */
    for (i=0; i<7; i++) {
        resource_size_t start, end;
        pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
        seq_printf(m, "\t%16llx",
            (unsigned long long)(start |
            (dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
    }
    for (i=0; i<7; i++) {
        resource_size_t start, end;
        pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
        seq_printf(m, "\t%16llx",
            dev->resource[i].start < dev->resource[i].end ?
            (unsigned long long)(end - start) + 1 : 0);
    }
    seq_putc(m, '\t');
    if (drv)
        seq_printf(m, "%s", drv->name);
    seq_putc(m, '\n');
    return 0;
}

在IRQ之后,它似乎是起始地址与前6个资源区域的标志相结合,然后是这些资源区域的长度,后跟已声明该设备的驱动程序的名称。