1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * rsrc_iodyn.c -- Resource management routines for MEM-static sockets.
4  *
5  * The initial developer of the original code is David A. Hinds
6  * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
7  * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
8  *
9  * (C) 1999		David A. Hinds
10  */
11 
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 
16 #include <pcmcia/ss.h>
17 #include <pcmcia/cistpl.h>
18 #include "cs_internal.h"
19 
20 
21 struct pcmcia_align_data {
22 	unsigned long	mask;
23 	unsigned long	offset;
24 };
25 
pcmcia_align(void * align_data,const struct resource * res,resource_size_t size,resource_size_t align)26 static resource_size_t pcmcia_align(void *align_data,
27 				const struct resource *res,
28 				resource_size_t size, resource_size_t align)
29 {
30 	struct pcmcia_align_data *data = align_data;
31 	resource_size_t start;
32 
33 	start = (res->start & ~data->mask) + data->offset;
34 	if (start < res->start)
35 		start += data->mask + 1;
36 
37 #ifdef CONFIG_X86
38 	if (res->flags & IORESOURCE_IO) {
39 		if (start & 0x300)
40 			start = (start + 0x3ff) & ~0x3ff;
41 	}
42 #endif
43 
44 #ifdef CONFIG_M68K
45 	if (res->flags & IORESOURCE_IO) {
46 		if ((res->start + size - 1) >= 1024)
47 			start = res->end;
48 	}
49 #endif
50 
51 	return start;
52 }
53 
54 
__iodyn_find_io_region(struct pcmcia_socket * s,unsigned long base,int num,unsigned long align)55 static struct resource *__iodyn_find_io_region(struct pcmcia_socket *s,
56 					unsigned long base, int num,
57 					unsigned long align)
58 {
59 	struct resource *res = pcmcia_make_resource(0, num, IORESOURCE_IO,
60 						dev_name(&s->dev));
61 	struct pcmcia_align_data data;
62 	unsigned long min = base;
63 	int ret;
64 
65 	data.mask = align - 1;
66 	data.offset = base & data.mask;
67 
68 #ifdef CONFIG_PCI
69 	if (s->cb_dev) {
70 		ret = pci_bus_alloc_resource(s->cb_dev->bus, res, num, 1,
71 					     min, 0, pcmcia_align, &data);
72 	} else
73 #endif
74 		ret = allocate_resource(&ioport_resource, res, num, min, ~0UL,
75 					1, pcmcia_align, &data);
76 
77 	if (ret != 0) {
78 		kfree(res);
79 		res = NULL;
80 	}
81 	return res;
82 }
83 
iodyn_find_io(struct pcmcia_socket * s,unsigned int attr,unsigned int * base,unsigned int num,unsigned int align,struct resource ** parent)84 static int iodyn_find_io(struct pcmcia_socket *s, unsigned int attr,
85 			unsigned int *base, unsigned int num,
86 			unsigned int align, struct resource **parent)
87 {
88 	int i, ret = 0;
89 
90 	/* Check for an already-allocated window that must conflict with
91 	 * what was asked for.  It is a hack because it does not catch all
92 	 * potential conflicts, just the most obvious ones.
93 	 */
94 	for (i = 0; i < MAX_IO_WIN; i++) {
95 		if (!s->io[i].res)
96 			continue;
97 
98 		if (!*base)
99 			continue;
100 
101 		if ((s->io[i].res->start & (align-1)) == *base)
102 			return -EBUSY;
103 	}
104 
105 	for (i = 0; i < MAX_IO_WIN; i++) {
106 		struct resource *res = s->io[i].res;
107 		unsigned int try;
108 
109 		if (res && (res->flags & IORESOURCE_BITS) !=
110 			(attr & IORESOURCE_BITS))
111 			continue;
112 
113 		if (!res) {
114 			if (align == 0)
115 				align = 0x10000;
116 
117 			res = s->io[i].res = __iodyn_find_io_region(s, *base,
118 								num, align);
119 			if (!res)
120 				return -EINVAL;
121 
122 			*base = res->start;
123 			s->io[i].res->flags =
124 				((res->flags & ~IORESOURCE_BITS) |
125 					(attr & IORESOURCE_BITS));
126 			s->io[i].InUse = num;
127 			*parent = res;
128 			return 0;
129 		}
130 
131 		/* Try to extend top of window */
132 		try = res->end + 1;
133 		if ((*base == 0) || (*base == try)) {
134 			if (adjust_resource(s->io[i].res, res->start,
135 					    resource_size(res) + num))
136 				continue;
137 			*base = try;
138 			s->io[i].InUse += num;
139 			*parent = res;
140 			return 0;
141 		}
142 
143 		/* Try to extend bottom of window */
144 		try = res->start - num;
145 		if ((*base == 0) || (*base == try)) {
146 			if (adjust_resource(s->io[i].res,
147 					    res->start - num,
148 					    resource_size(res) + num))
149 				continue;
150 			*base = try;
151 			s->io[i].InUse += num;
152 			*parent = res;
153 			return 0;
154 		}
155 	}
156 
157 	return -EINVAL;
158 }
159 
160 
161 struct pccard_resource_ops pccard_iodyn_ops = {
162 	.validate_mem = NULL,
163 	.find_io = iodyn_find_io,
164 	.find_mem = NULL,
165 	.init = static_init,
166 	.exit = NULL,
167 };
168 EXPORT_SYMBOL(pccard_iodyn_ops);
169