diff options
Diffstat (limited to 'src/soc/intel/common/block/pcie/pcie_rp.c')
| -rw-r--r-- | src/soc/intel/common/block/pcie/pcie_rp.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/src/soc/intel/common/block/pcie/pcie_rp.c b/src/soc/intel/common/block/pcie/pcie_rp.c index 221ee03a9423..145159f6eb66 100644 --- a/src/soc/intel/common/block/pcie/pcie_rp.c +++ b/src/soc/intel/common/block/pcie/pcie_rp.c @@ -31,20 +31,25 @@ static int pcie_rp_original_idx( } const uint32_t lcap = pci_s_read_config32(dev, clist + PCI_EXP_LNKCAP); - /* Read 1-based absolute port number. This reflects the numbering - scheme that Intel uses in their documentation and what we use - as index (0-based, though) in our mapping. */ + + /* Read n-based absolute port number from LCAP register. + This reflects the numbering scheme that Intel uses in their + documentation and what we use as index (0-based, though) in + our mapping. */ const unsigned int port_num = (lcap & PCI_EXP_LNKCAP_PORT) >> 24; - /* `port_num` is 1-based, `offset` is 0-based. */ - if (port_num <= offset || port_num > offset + group->count) { + /* Subtract lcap_port_base from port_num to get 0-based index */ + const unsigned int port_idx = port_num - group->lcap_port_base; + + /* Check if port_idx (0-based) is out of bounds */ + if (port_idx < offset || port_idx >= offset + group->count) { printk(BIOS_WARNING, "%s: Unexpected root-port number '%u'" " at PCI: 00:%02x.%x, ignoring.\n", __func__, port_num, group->slot, PCI_FUNC(PCI_DEV2DEVFN(dev))); return -1; } - return port_num - 1; + return port_idx; } /* Scan actual PCI config space to reconstruct current mapping */ |