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 <log.h>
18 #include <pci.h>
19 
pciauto_region_init(struct pci_region * res)20 void pciauto_region_init(struct pci_region *res)
21 {
22 	/*
23 	 * Avoid allocating PCI resources from address 0 -- this is illegal
24 	 * according to PCI 2.1 and moreover, this is known to cause Linux IDE
25 	 * drivers to fail. Use a reasonable starting value of 0x1000 instead
26 	 * if the bus start address is below 0x1000.
27 	 */
28 	res->bus_lower = res->bus_start < 0x1000 ? 0x1000 : res->bus_start;
29 }
30 
pciauto_region_align(struct pci_region * res,pci_size_t size)31 void pciauto_region_align(struct pci_region *res, pci_size_t size)
32 {
33 	res->bus_lower = ((res->bus_lower - 1) | (size - 1)) + 1;
34 }
35 
pciauto_region_allocate(struct pci_region * res,pci_size_t size,pci_addr_t * bar,bool supports_64bit)36 int pciauto_region_allocate(struct pci_region *res, pci_size_t size,
37 	pci_addr_t *bar, bool supports_64bit)
38 {
39 	pci_addr_t addr;
40 
41 	if (!res) {
42 		debug("No resource\n");
43 		goto error;
44 	}
45 
46 	addr = ((res->bus_lower - 1) | (size - 1)) + 1;
47 
48 	if (addr - res->bus_start + size > res->size) {
49 		debug("No room in resource, avail start=%llx / size=%llx, "
50 		      "need=%llx\n", (unsigned long long)res->bus_lower,
51 		      (unsigned long long)res->size, (unsigned long long)size);
52 		goto error;
53 	}
54 
55 	if (upper_32_bits(addr) && !supports_64bit) {
56 		debug("Cannot assign 64-bit address to 32-bit-only resource\n");
57 		goto error;
58 	}
59 
60 	res->bus_lower = addr + size;
61 
62 	debug("address=0x%llx bus_lower=0x%llx\n", (unsigned long long)addr,
63 	      (unsigned long long)res->bus_lower);
64 
65 	*bar = addr;
66 	return 0;
67 
68  error:
69 	*bar = (pci_addr_t)-1;
70 	return -1;
71 }
72 
pciauto_show_region(const char * name,struct pci_region * region)73 static void pciauto_show_region(const char *name, struct pci_region *region)
74 {
75 	pciauto_region_init(region);
76 	debug("PCI Autoconfig: Bus %s region: [%llx-%llx],\n"
77 	      "\t\tPhysical Memory [%llx-%llxx]\n", name,
78 	      (unsigned long long)region->bus_start,
79 	      (unsigned long long)(region->bus_start + region->size - 1),
80 	      (unsigned long long)region->phys_start,
81 	      (unsigned long long)(region->phys_start + region->size - 1));
82 }
83 
pciauto_config_init(struct pci_controller * hose)84 void pciauto_config_init(struct pci_controller *hose)
85 {
86 	int i;
87 
88 	hose->pci_io = NULL;
89 	hose->pci_mem = NULL;
90 	hose->pci_prefetch = NULL;
91 
92 	for (i = 0; i < hose->region_count; i++) {
93 		switch (hose->regions[i].flags) {
94 		case PCI_REGION_IO:
95 			if (!hose->pci_io ||
96 			    hose->pci_io->size < hose->regions[i].size)
97 				hose->pci_io = hose->regions + i;
98 			break;
99 		case PCI_REGION_MEM:
100 			if (!hose->pci_mem ||
101 			    hose->pci_mem->size < hose->regions[i].size)
102 				hose->pci_mem = hose->regions + i;
103 			break;
104 		case (PCI_REGION_MEM | PCI_REGION_PREFETCH):
105 			if (!hose->pci_prefetch ||
106 			    hose->pci_prefetch->size < hose->regions[i].size)
107 				hose->pci_prefetch = hose->regions + i;
108 			break;
109 		}
110 	}
111 
112 
113 	if (hose->pci_mem)
114 		pciauto_show_region("Memory", hose->pci_mem);
115 	if (hose->pci_prefetch)
116 		pciauto_show_region("Prefetchable Mem", hose->pci_prefetch);
117 	if (hose->pci_io)
118 		pciauto_show_region("I/O", hose->pci_io);
119 }
120