From dac01fd89d41d98cd4ce040a0d10eb67c523f63a Mon Sep 17 00:00:00 2001 From: Bin Meng Date: Fri, 3 Aug 2018 01:14:52 -0700 Subject: dm: pci: Add APIs to find capability and extended capability This introduces two new APIs dm_pci_find_capability() and dm_pci_find_ext_capability() to get PCI capability address and PCI express extended capability address for a given PCI device. Signed-off-by: Bin Meng Reviewed-by: Simon Glass --- drivers/pci/pci-uclass.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index 5eb68415cd..e9671d9b76 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -1320,6 +1320,74 @@ void *dm_pci_map_bar(struct udevice *dev, int bar, int flags) return dm_pci_bus_to_virt(dev, pci_bus_addr, flags, 0, MAP_NOCACHE); } +int dm_pci_find_capability(struct udevice *dev, int cap) +{ + u16 status; + u8 header_type; + int ttl = PCI_FIND_CAP_TTL; + u8 id; + u16 ent; + u8 pos; + + dm_pci_read_config16(dev, PCI_STATUS, &status); + if (!(status & PCI_STATUS_CAP_LIST)) + return 0; + + dm_pci_read_config8(dev, PCI_HEADER_TYPE, &header_type); + if ((header_type & 0x7f) == PCI_HEADER_TYPE_CARDBUS) + pos = PCI_CB_CAPABILITY_LIST; + else + pos = PCI_CAPABILITY_LIST; + + dm_pci_read_config8(dev, pos, &pos); + while (ttl--) { + if (pos < PCI_STD_HEADER_SIZEOF) + break; + pos &= ~3; + dm_pci_read_config16(dev, pos, &ent); + + id = ent & 0xff; + if (id == 0xff) + break; + if (id == cap) + return pos; + pos = (ent >> 8); + } + + return 0; +} + +int dm_pci_find_ext_capability(struct udevice *dev, int cap) +{ + u32 header; + int ttl; + int pos = PCI_CFG_SPACE_SIZE; + + /* minimum 8 bytes per capability */ + ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8; + + dm_pci_read_config32(dev, pos, &header); + /* + * If we have no capabilities, this is indicated by cap ID, + * cap version and next pointer all being 0. + */ + if (header == 0) + return 0; + + while (ttl--) { + if (PCI_EXT_CAP_ID(header) == cap) + return pos; + + pos = PCI_EXT_CAP_NEXT(header); + if (pos < PCI_CFG_SPACE_SIZE) + break; + + dm_pci_read_config32(dev, pos, &header); + } + + return 0; +} + UCLASS_DRIVER(pci) = { .id = UCLASS_PCI, .name = "pci", -- cgit v1.2.3