Hi Bin,

On 21 July 2015 at 10:12, Bin Meng <bmeng...@gmail.com> wrote:
> Hi Simon,
>
> On Tue, Jul 7, 2015 at 6:47 AM, Simon Glass <s...@chromium.org> wrote:
>> At present all PCI devices must be present in the device tree in order to
>> be used. Many or most PCI devices don't require any configuration other than
>> that which is done automatically by U-Boot. It is inefficent to add a node
>> with nothing but a compatible string in order to get a device working.
>>
>> Add a mechanism whereby PCI drivers can be declared along with the device
>> parameters they support (vendor/device/class). When no suitable driver is
>> found in the device tree the list of such devices is consulted to determine
>> the correct driver. If this also fails, then a generic driver is used as
>> before.
>>
>> The mechanism used is very similar to that provided by Linux and the header
>> file defintions are copied from Linux 4.1.
>>
>> Signed-off-by: Simon Glass <s...@chromium.org>
>> ---
>>
>>  drivers/pci/pci-uclass.c | 129 
>> ++++++++++++++++++++++++++++++++++++++++++-----
>>  include/pci.h            |  79 ++++++++++++++++++++++++++++-
>>  2 files changed, 193 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
>> index 5b91fe3..41daa0d 100644
>> --- a/drivers/pci/pci-uclass.c
>> +++ b/drivers/pci/pci-uclass.c
>> @@ -353,6 +353,101 @@ int dm_pci_hose_probe_bus(struct pci_controller *hose, 
>> pci_dev_t bdf)
>>         return sub_bus;
>>  }
>>
>> +/**
>> + * pci_match_one_device - Tell if a PCI device structure has a matching
>> + *                        PCI device id structure
>> + * @id: single PCI device id structure to match
>> + * @dev: the PCI device structure to match against
>> + *
>> + * Returns the matching pci_device_id structure or %NULL if there is no 
>> match.
>> + */
>> +static bool pci_match_one_id(const struct pci_device_id *id,
>> +                            const struct pci_device_id *find)
>> +{
>> +       if ((id->vendor == PCI_ANY_ID || id->vendor == find->vendor) &&
>> +           (id->device == PCI_ANY_ID || id->device == find->device) &&
>> +           (id->subvendor == PCI_ANY_ID || id->subvendor == 
>> find->subvendor) &&
>> +           (id->subdevice == PCI_ANY_ID || id->subdevice == 
>> find->subdevice) &&
>> +           !((id->class ^ find->class) & id->class_mask))
>> +               return true;
>> +
>> +       return false;
>> +}
>> +
>> +/**
>> + * pci_find_and_bind_driver() - Find and bind the right PCI driver
>> + *
>> + * This only looks at certain fields in the descriptor.
>> + */
>> +static int pci_find_and_bind_driver(struct udevice *parent,
>> +                                   struct pci_device_id *find_id, int devfn,
>> +                                   struct udevice **devp)
>> +{
>> +       struct pci_driver_entry *start, *entry;
>> +       const char *drv;
>> +       int n_ents;
>> +       int ret;
>> +       char name[30], *str;
>> +
>> +       *devp = NULL;
>> +
>> +       debug("%s: Searching for driver: vendor=%x, device=%x\n", __func__,
>> +             find_id->vendor, find_id->device);
>> +       start = ll_entry_start(struct pci_driver_entry, pci_driver_entry);
>> +       n_ents = ll_entry_count(struct pci_driver_entry, pci_driver_entry);
>> +       for (entry = start; entry != start + n_ents; entry++) {
>> +               const struct pci_device_id *id;
>> +               struct udevice *dev;
>> +               const struct driver *drv;
>> +
>> +               for (id = entry->match;
>> +                    id->vendor || id->subvendor || id->class_mask;
>> +                    id++) {
>> +                       if (!pci_match_one_id(id, find_id))
>> +                               continue;
>> +
>> +                       drv = entry->driver;
>> +                       /*
>> +                        * We could pass the descriptor to the driver as
>> +                        * platdata (instead of NULL) and allow its bind()
>> +                        * method to return -ENOENT if it doesn't support 
>> this
>> +                        * device. That way we could continue the search to
>> +                        * find another driver. For now this doesn't seem
>> +                        * necesssary, so just bind the first match.
>> +                        */
>> +                       ret = device_bind(parent, drv, drv->name, NULL, -1,
>> +                                         &dev);
>> +                       if (ret)
>> +                               goto error;
>> +                       debug("%s: Match found: %s\n", __func__, drv->name);
>> +                       dev->driver_data = find_id->driver_data;
>> +                       *devp = dev;
>> +                       return 0;
>> +               }
>> +       }
>> +
>> +       /* Bind a generic driver so that the device can be used */
>> +       sprintf(name, "pci_%x:%x.%x", parent->seq, PCI_DEV(devfn),
>> +               PCI_FUNC(devfn));
>> +       str = strdup(name);
>> +       if (!str)
>> +               return -ENOMEM;
>> +       drv = (find_id->class >> 8) == PCI_CLASS_BRIDGE_PCI ? 
>> "pci_bridge_drv" :
>> +                       "pci_generic_drv";
>> +       ret = device_bind_driver(parent, drv, str, devp);
>> +       if (ret) {
>> +               debug("%s: Failed to bind generic driver: %d", __func__, 
>> ret);
>> +               return ret;
>> +       }
>> +       debug("%s: No match found: bound generic driver instead\n", 
>> __func__);
>> +
>> +       return 0;
>> +
>> +error:
>> +       debug("%s: No match found: error %d\n", __func__, ret);
>> +       return ret;
>> +}
>> +
>>  int pci_bind_bus_devices(struct udevice *bus)
>>  {
>>         ulong vendor, device;
>> @@ -387,25 +482,33 @@ int pci_bind_bus_devices(struct udevice *bus)
>>                       bus->seq, bus->name, PCI_DEV(devfn), PCI_FUNC(devfn));
>>                 pci_bus_read_config(bus, devfn, PCI_DEVICE_ID, &device,
>>                                     PCI_SIZE_16);
>> -               pci_bus_read_config(bus, devfn, PCI_CLASS_DEVICE, &class,
>> -                                   PCI_SIZE_16);
>> +               pci_bus_read_config(bus, devfn, PCI_CLASS_REVISION, &class,
>> +                                   PCI_SIZE_32);
>> +               class >>= 8;
>>
>>                 /* Find this device in the device tree */
>>                 ret = pci_bus_find_devfn(bus, devfn, &dev);
>>
>> +               /* Search for a driver */
>> +
>>                 /* If nothing in the device tree, bind a generic device */
>>                 if (ret == -ENODEV) {
>> -                       char name[30], *str;
>> -                       const char *drv;
>> -
>> -                       sprintf(name, "pci_%x:%x.%x", bus->seq,
>> -                               PCI_DEV(devfn), PCI_FUNC(devfn));
>> -                       str = strdup(name);
>> -                       if (!str)
>> -                               return -ENOMEM;
>> -                       drv = class == PCI_CLASS_BRIDGE_PCI ?
>> -                               "pci_bridge_drv" : "pci_generic_drv";
>> -                       ret = device_bind_driver(bus, drv, str, &dev);
>> +                       struct pci_device_id find_id;
>> +                       ulong val;
>> +
>> +                       memset(&find_id, '\0', sizeof(find_id));
>> +                       find_id.vendor = vendor;
>> +                       find_id.device = device;
>> +                       find_id.class = class;
>> +                       if ((header_type & 0x7f) == PCI_HEADER_TYPE_NORMAL) {
>> +                               pci_bus_read_config(bus, devfn,
>> +                                                   PCI_SUBSYSTEM_VENDOR_ID,
>> +                                                   &val, PCI_SIZE_32);
>> +                               find_id.subvendor = val & 0xffff;
>> +                               find_id.subdevice = val >> 16;
>> +                       }
>> +                       ret = pci_find_and_bind_driver(bus, &find_id, devfn,
>> +                                                      &dev);
>>                 }
>>                 if (ret)
>>                         return ret;
>> diff --git a/include/pci.h b/include/pci.h
>> index 3af511b..d21fa8b 100644
>> --- a/include/pci.h
>> +++ b/include/pci.h
>> @@ -468,7 +468,10 @@ typedef int pci_dev_t;
>>  #define PCI_ANY_ID             (~0)
>>
>>  struct pci_device_id {
>> -       unsigned int vendor, device;            /* Vendor and device ID or 
>> PCI_ANY_ID */
>> +       unsigned int vendor, device;    /* Vendor and device ID or 
>> PCI_ANY_ID */
>> +       unsigned int subvendor, subdevice; /* Subsystem ID's or PCI_ANY_ID */
>> +       unsigned int class, class_mask; /* (class,subclass,prog-if) triplet 
>> */
>> +       unsigned long driver_data;      /* Data private to the driver */
>>  };
>
> Can we create another structure for dm? There are lots of codes which
> only defines vendor id and device id like below:
>
> static struct pci_device_id mmc_supported[] = {
>         { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TCF_SDIO_0 },
>         { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TCF_SDIO_1 },
> };
>
> Although compiler does not generate any error or warning, it is confusing.

I think the existing structure is for exactly this purpose, - I have
just added a few new fields. Why do we want to change it? I also
really want to use this name as it matches Linux.

>
>>
>>  struct pci_controller;
>> @@ -1110,7 +1113,79 @@ struct dm_pci_emul_ops {
>>  int sandbox_pci_get_emul(struct udevice *bus, pci_dev_t find_devfn,
>>                          struct udevice **emulp);
>>
>> -#endif
>> +/**
>> + * PCI_DEVICE - macro used to describe a specific pci device
>> + * @vend: the 16 bit PCI Vendor ID
>> + * @dev: the 16 bit PCI Device ID
>> + *
>> + * This macro is used to create a struct pci_device_id that matches a
>> + * specific device.  The subvendor and subdevice fields will be set to
>> + * PCI_ANY_ID.
>> + */
>> +#define PCI_DEVICE(vend, dev) \
>> +       .vendor = (vend), .device = (dev), \
>> +       .subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID
>> +
>> +/**
>> + * PCI_DEVICE_SUB - macro used to describe a specific pci device with 
>> subsystem
>> + * @vend: the 16 bit PCI Vendor ID
>> + * @dev: the 16 bit PCI Device ID
>> + * @subvend: the 16 bit PCI Subvendor ID
>> + * @subdev: the 16 bit PCI Subdevice ID
>> + *
>> + * This macro is used to create a struct pci_device_id that matches a
>> + * specific device with subsystem information.
>> + */
>> +#define PCI_DEVICE_SUB(vend, dev, subvend, subdev) \
>> +       .vendor = (vend), .device = (dev), \
>> +       .subvendor = (subvend), .subdevice = (subdev)
>> +
>> +/**
>> + * PCI_DEVICE_CLASS - macro used to describe a specific pci device class
>> + * @dev_class: the class, subclass, prog-if triple for this device
>> + * @dev_class_mask: the class mask for this device
>> + *
>> + * This macro is used to create a struct pci_device_id that matches a
>> + * specific PCI class.  The vendor, device, subvendor, and subdevice
>> + * fields will be set to PCI_ANY_ID.
>> + */
>> +#define PCI_DEVICE_CLASS(dev_class, dev_class_mask) \
>> +       .class = (dev_class), .class_mask = (dev_class_mask), \
>> +       .vendor = PCI_ANY_ID, .device = PCI_ANY_ID, \
>> +       .subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID
>> +
>> +/**
>> + * PCI_VDEVICE - macro used to describe a specific pci device in short form
>> + * @vend: the vendor name
>> + * @dev: the 16 bit PCI Device ID
>> + *
>> + * This macro is used to create a struct pci_device_id that matches a
>> + * specific PCI device.  The subvendor, and subdevice fields will be set
>> + * to PCI_ANY_ID. The macro allows the next field to follow as the device
>> + * private data.
>> + */
>> +
>> +#define PCI_VDEVICE(vend, dev) \
>> +       .vendor = PCI_VENDOR_ID_##vend, .device = (dev), \
>> +       .subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID, 0, 0
>> +
>> +/**
>> + * struct pci_driver_entry - Matches a driver to its pci_device_id list
>> + * @driver: Driver to use
>> + * @match: List of match records for this driver, terminated by {}
>> + */
>> +struct pci_driver_entry {
>> +       struct driver *driver;
>> +       const struct pci_device_id *match;
>> +};
>> +
>> +#define U_BOOT_PCI_DEVICE(__name, __match)                             \
>> +       ll_entry_declare(struct pci_driver_entry, __name, pci_driver_entry) 
>> = {\
>> +               .driver = llsym(struct driver, __name, driver), \
>> +               .match = __match, \
>> +               }
>> +
>> +#endif /* CONFIG_DM_PCI */
>>
>>  #endif /* __ASSEMBLY__ */
>>  #endif /* _PCI_H */
>> --
>
> Do you have plan to address the issue that dm pci cannot be used in
> the pre-reloc phase? Like we need pci uart as the U-Boot console.

Regards,
Simon
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