diff options
Diffstat (limited to 'src/soc/intel/common/block')
| -rw-r--r-- | src/soc/intel/common/block/include/intelblocks/pcie_rp.h | 50 | ||||
| -rw-r--r-- | src/soc/intel/common/block/pcie/Makefile.inc | 1 | ||||
| -rw-r--r-- | src/soc/intel/common/block/pcie/pcie_rp.c | 177 |
3 files changed, 228 insertions, 0 deletions
diff --git a/src/soc/intel/common/block/include/intelblocks/pcie_rp.h b/src/soc/intel/common/block/include/intelblocks/pcie_rp.h new file mode 100644 index 0000000000..52fde28310 --- /dev/null +++ b/src/soc/intel/common/block/include/intelblocks/pcie_rp.h @@ -0,0 +1,50 @@ +/* + * This file is part of the coreboot project. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef SOC_INTEL_COMMON_BLOCK_PCIE_RP_H +#define SOC_INTEL_COMMON_BLOCK_PCIE_RP_H + +#include <stdint.h> + +/* + * The PCIe Root Ports usually come in groups of up to 8 PCI-device + * functions. + * + * `slot` is the PCI device/slot number of such a group. + * `count` is the number of functions within the group. It is assumed that + * the first group includes the RPs 1 to the first group's `count` and that + * adjacent groups follow without gaps in the numbering. + */ +struct pcie_rp_group { + unsigned int slot; + unsigned int count; +}; + +/* + * Update PCI paths of the root ports in the devicetree. + * + * Depending on the board layout and physical presence of downstream + * devices, individual root-port functions can be hidden and reordered. + * If we have device nodes for root ports in the static `devicetree.cb`, + * we need to update their PCI paths, so the nodes still control the + * correct root port. Device nodes for disabled root ports will be + * unlinked from the bus, to not interfere with PCI enumeration. + * + * Call this once, after root ports have been reordered, but before PCI + * enumeration. + * + * `groups` points to a list of groups terminated by an entry with `count == 0`. + */ +void pcie_rp_update_devicetree(const struct pcie_rp_group *groups); + +#endif /* SOC_INTEL_COMMON_BLOCK_PCIE_RP_H */ diff --git a/src/soc/intel/common/block/pcie/Makefile.inc b/src/soc/intel/common/block/pcie/Makefile.inc index ac311a7abd..0cded9dce7 100644 --- a/src/soc/intel/common/block/pcie/Makefile.inc +++ b/src/soc/intel/common/block/pcie/Makefile.inc @@ -1 +1,2 @@ ramstage-$(CONFIG_SOC_INTEL_COMMON_BLOCK_PCIE) += pcie.c +ramstage-$(CONFIG_SOC_INTEL_COMMON_BLOCK_PCIE) += pcie_rp.c diff --git a/src/soc/intel/common/block/pcie/pcie_rp.c b/src/soc/intel/common/block/pcie/pcie_rp.c new file mode 100644 index 0000000000..96f92f0861 --- /dev/null +++ b/src/soc/intel/common/block/pcie/pcie_rp.c @@ -0,0 +1,177 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2019 Nico Huber <nico.h@gmx.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <stdint.h> + +#include <commonlib/helpers.h> +#include <console/console.h> +#include <device/device.h> +#include <device/pci_def.h> +#include <device/pci_ops.h> +#include <device/pci_type.h> +#include <intelblocks/pcie_rp.h> + +static int pcie_rp_original_idx( + const struct pcie_rp_group *const group, + const unsigned int offset, + const pci_devfn_t dev) +{ + const uint16_t clist = pci_s_find_capability(dev, PCI_CAP_ID_PCIE); + if (clist == 0) { + printk(BIOS_WARNING, + "%s: Can't find PCIe capapilities for PCI: 00:%02x.%x, ignoring.\n", + __func__, group->slot, PCI_FUNC(PCI_DEV2DEVFN(dev))); + return -1; + } + + const uint16_t xcap = pci_s_read_config16(dev, clist + PCI_EXP_FLAGS); + if ((xcap & PCI_EXP_FLAGS_TYPE) >> 4 != PCI_EXP_TYPE_ROOT_PORT) { + printk(BIOS_WARNING, "%s: Non root-port found at PCI: 00:%02x.%x, ignoring.\n", + __func__, group->slot, PCI_FUNC(PCI_DEV2DEVFN(dev))); + return -1; + } + + 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. */ + 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) { + 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; +} + +/* Scan actual PCI config space to reconstruct current mapping */ +static void pcie_rp_scan_groups(int mapping[], const struct pcie_rp_group *const groups) +{ + unsigned int offset = 0; + const struct pcie_rp_group *group; + for (group = groups; group->count; ++group) { + unsigned int fn; + for (fn = 0; fn < group->count; ++fn) { + const pci_devfn_t dev = PCI_DEV(0, group->slot, fn); + const uint16_t did = pci_s_read_config16(dev, PCI_DEVICE_ID); + if (did == 0xffff) { + if (fn == 0) + break; + continue; + } + + const int rp_idx = pcie_rp_original_idx(group, offset, dev); + if (rp_idx < 0) + continue; + if (mapping[rp_idx] != -1) { + printk(BIOS_WARNING, "%s: Root Port #%u reported by PCI: " + "00:%02x.%x already reported by PCI: 00:%02x.%x!\n", + __func__, rp_idx + 1, group->slot, fn, + group->slot, mapping[rp_idx]); + continue; + } + + printk(BIOS_INFO, "Found PCIe Root Port #%u at PCI: 00:%02x.%x.\n", + rp_idx + 1, group->slot, fn); + mapping[rp_idx] = fn; + } + offset += group->count; + } +} + +/* Returns `true` if the device should be unlinked. */ +static bool pcie_rp_update_dev( + struct device *const dev, + const struct pcie_rp_group *const groups, + const int mapping[]) +{ + if (dev->path.type != DEVICE_PATH_PCI) + return false; + + /* Find matching group and offset. */ + unsigned int offset = 0; + const struct pcie_rp_group *group; + for (group = groups; group->count; ++group) { + if (PCI_SLOT(dev->path.pci.devfn) == group->slot && + PCI_FUNC(dev->path.pci.devfn) < group->count) + break; + offset += group->count; + } + if (!group->count) + return false; + + /* Now update based on what we know. */ + const int rp_idx = offset + PCI_FUNC(dev->path.pci.devfn); + const int new_fn = mapping[rp_idx]; + if (new_fn < 0) { + if (dev->enabled) { + printk(BIOS_NOTICE, "%s: Couldn't find PCIe Root Port #%u " + "(originally %s) which was enabled in devicetree, removing.\n", + __func__, rp_idx + 1, dev_path(dev)); + } + return true; + } else if (PCI_FUNC(dev->path.pci.devfn) != new_fn) { + printk(BIOS_INFO, + "Remapping PCIe Root Port #%u from %s to new function number %u.\n", + rp_idx + 1, dev_path(dev), new_fn); + dev->path.pci.devfn = PCI_DEVFN(PCI_SLOT(dev->path.pci.devfn), new_fn); + } + return false; +} + +void pcie_rp_update_devicetree(const struct pcie_rp_group *const groups) +{ + /* Maps absolute root-port numbers to function numbers. + Negative if disabled, new function number otherwise. */ + int mapping[CONFIG_MAX_ROOT_PORTS]; + unsigned int offset, i; + + struct bus *const root = pci_root_bus(); + if (!root) + return; + + offset = 0; + const struct pcie_rp_group *group; + for (group = groups; group->count; ++group) + offset += group->count; + + if (offset > ARRAY_SIZE(mapping)) { + printk(BIOS_ERR, "%s: Error: Group exceeds CONFIG_MAX_ROOT_PORTS.\n", __func__); + return; + } + + /* Assume everything we don't encounter later is disabled */ + for (i = 0; i < ARRAY_SIZE(mapping); ++i) + mapping[i] = -1; + + pcie_rp_scan_groups(mapping, groups); + + struct device *dev; + struct device **link = &root->children; + for (dev = *link; dev; dev = *link) { + if (pcie_rp_update_dev(dev, groups, mapping)) { + /* Unlink vanished device. */ + *link = dev->sibling; + dev->sibling = NULL; + continue; + } + + link = &dev->sibling; + } +} |