1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * PCI auto-configuration library
4  *
5  * Author: Matt Porter <mporter@mvista.com>
6  *
7  * Copyright 2000 MontaVista Software Inc.
8  *
9  * Modifications for driver model:
10  * Copyright 2015 Google, Inc
11  * Written by Simon Glass <sjg@chromium.org>
12  */
13 
14 #include <common.h>
15 #include <dm.h>
16 #include <errno.h>
17 #include <pci.h>
18 
19 void pciauto_region_init(struct pci_region *res)
20 {
21 	/*
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.
25 	 */
26 	res->bus_lower = res->bus_start ? res->bus_start : 0x1000;
27 }
28 
29 void pciauto_region_align(struct pci_region *res, pci_size_t size)
30 {
31 	res->bus_lower = ((res->bus_lower - 1) | (size - 1)) + 1;
32 }
33 
34 int pciauto_region_allocate(struct pci_region *res, pci_size_t size,
35 	pci_addr_t *bar, bool supports_64bit)
36 {
37 	pci_addr_t addr;
38 
39 	if (!res) {
40 		debug("No resource\n");
41 		goto error;
42 	}
43 
44 	addr = ((res->bus_lower - 1) | (size - 1)) + 1;
45 
46 	if (addr - res->bus_start + size > res->size) {
47 		debug("No room in resource");
48 		goto error;
49 	}
50 
51 	if (upper_32_bits(addr) && !supports_64bit) {
52 		debug("Cannot assign 64-bit address to 32-bit-only resource\n");
53 		goto error;
54 	}
55 
56 	res->bus_lower = addr + size;
57 
58 	debug("address=0x%llx bus_lower=0x%llx\n", (unsigned long long)addr,
59 	      (unsigned long long)res->bus_lower);
60 
61 	*bar = addr;
62 	return 0;
63 
64  error:
65 	*bar = (pci_addr_t)-1;
66 	return -1;
67 }
68 
69 static void pciauto_show_region(const char *name, struct pci_region *region)
70 {
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));
78 }
79 
80 void pciauto_config_init(struct pci_controller *hose)
81 {
82 	int i;
83 
84 	hose->pci_io = NULL;
85 	hose->pci_mem = NULL;
86 	hose->pci_prefetch = NULL;
87 
88 	for (i = 0; i < hose->region_count; i++) {
89 		switch (hose->regions[i].flags) {
90 		case PCI_REGION_IO:
91 			if (!hose->pci_io ||
92 			    hose->pci_io->size < hose->regions[i].size)
93 				hose->pci_io = hose->regions + i;
94 			break;
95 		case PCI_REGION_MEM:
96 			if (!hose->pci_mem ||
97 			    hose->pci_mem->size < hose->regions[i].size)
98 				hose->pci_mem = hose->regions + i;
99 			break;
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;
104 			break;
105 		}
106 	}
107 
108 
109 	if (hose->pci_mem)
110 		pciauto_show_region("Memory", hose->pci_mem);
111 	if (hose->pci_prefetch)
112 		pciauto_show_region("Prefetchable Mem", hose->pci_prefetch);
113 	if (hose->pci_io)
114 		pciauto_show_region("I/O", hose->pci_io);
115 }
116