1 // SPDX-License-Identifier: GPL-2.0+
3 * PCI auto-configuration library
5 * Author: Matt Porter <mporter@mvista.com>
7 * Copyright 2000 MontaVista Software Inc.
9 * Modifications for driver model:
10 * Copyright 2015 Google, Inc
11 * Written by Simon Glass <sjg@chromium.org>
19 void pciauto_region_init(struct pci_region *res)
22 * Avoid allocating PCI resources from address 0 -- this is illegal
23 * according to PCI 2.1 and moreover, this is known to cause Linux IDE
24 * drivers to fail. Use a reasonable starting value of 0x1000 instead.
26 res->bus_lower = res->bus_start ? res->bus_start : 0x1000;
29 void pciauto_region_align(struct pci_region *res, pci_size_t size)
31 res->bus_lower = ((res->bus_lower - 1) | (size - 1)) + 1;
34 int pciauto_region_allocate(struct pci_region *res, pci_size_t size,
35 pci_addr_t *bar, bool supports_64bit)
40 debug("No resource\n");
44 addr = ((res->bus_lower - 1) | (size - 1)) + 1;
46 if (addr - res->bus_start + size > res->size) {
47 debug("No room in resource");
51 if (upper_32_bits(addr) && !supports_64bit) {
52 debug("Cannot assign 64-bit address to 32-bit-only resource\n");
56 res->bus_lower = addr + size;
58 debug("address=0x%llx bus_lower=0x%llx\n", (unsigned long long)addr,
59 (unsigned long long)res->bus_lower);
65 *bar = (pci_addr_t)-1;
69 static void pciauto_show_region(const char *name, struct pci_region *region)
71 pciauto_region_init(region);
72 debug("PCI Autoconfig: Bus %s region: [%llx-%llx],\n"
73 "\t\tPhysical Memory [%llx-%llxx]\n", name,
74 (unsigned long long)region->bus_start,
75 (unsigned long long)(region->bus_start + region->size - 1),
76 (unsigned long long)region->phys_start,
77 (unsigned long long)(region->phys_start + region->size - 1));
80 void pciauto_config_init(struct pci_controller *hose)
86 hose->pci_prefetch = NULL;
88 for (i = 0; i < hose->region_count; i++) {
89 switch (hose->regions[i].flags) {
92 hose->pci_io->size < hose->regions[i].size)
93 hose->pci_io = hose->regions + i;
97 hose->pci_mem->size < hose->regions[i].size)
98 hose->pci_mem = hose->regions + i;
100 case (PCI_REGION_MEM | PCI_REGION_PREFETCH):
101 if (!hose->pci_prefetch ||
102 hose->pci_prefetch->size < hose->regions[i].size)
103 hose->pci_prefetch = hose->regions + i;
110 pciauto_show_region("Memory", hose->pci_mem);
111 if (hose->pci_prefetch)
112 pciauto_show_region("Prefetchable Mem", hose->pci_prefetch);
114 pciauto_show_region("I/O", hose->pci_io);