[U-Boot] [PATCH 05/18] dm: pci: Add support for PCI driver matching
Simon Glass
sjg at chromium.org
Wed Jul 22 00:00:21 CEST 2015
Hi Bin,
On 21 July 2015 at 10:12, Bin Meng <bmeng.cn at gmail.com> wrote:
> Hi Simon,
>
> On Tue, Jul 7, 2015 at 6:47 AM, Simon Glass <sjg at 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 <sjg at 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
More information about the U-Boot
mailing list