xref: /openbmc/linux/drivers/tc/tc.c (revision 0936cdfb)
1 /*
2  *	TURBOchannel bus services.
3  *
4  *	Copyright (c) Harald Koerfgen, 1998
5  *	Copyright (c) 2001, 2003, 2005, 2006, 2018  Maciej W. Rozycki
6  *	Copyright (c) 2005  James Simmons
7  *
8  *	This file is subject to the terms and conditions of the GNU
9  *	General Public License.  See the file "COPYING" in the main
10  *	directory of this archive for more details.
11  */
12 #include <linux/compiler.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/errno.h>
15 #include <linux/init.h>
16 #include <linux/ioport.h>
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
22 #include <linux/tc.h>
23 #include <linux/types.h>
24 
25 #include <asm/io.h>
26 
27 static struct tc_bus tc_bus = {
28 	.name = "TURBOchannel",
29 };
30 
31 /*
32  * Probing for TURBOchannel modules.
33  */
34 static void __init tc_bus_add_devices(struct tc_bus *tbus)
35 {
36 	resource_size_t slotsize = tbus->info.slot_size << 20;
37 	resource_size_t extslotsize = tbus->ext_slot_size;
38 	resource_size_t slotaddr;
39 	resource_size_t extslotaddr;
40 	resource_size_t devsize;
41 	void __iomem *module;
42 	struct tc_dev *tdev;
43 	int i, slot, err;
44 	u8 pattern[4];
45 	long offset;
46 
47 	for (slot = 0; slot < tbus->num_tcslots; slot++) {
48 		slotaddr = tbus->slot_base + slot * slotsize;
49 		extslotaddr = tbus->ext_slot_base + slot * extslotsize;
50 		module = ioremap(slotaddr, slotsize);
51 		BUG_ON(!module);
52 
53 		offset = TC_OLDCARD;
54 
55 		err = 0;
56 		err |= tc_preadb(pattern + 0, module + offset + TC_PATTERN0);
57 		err |= tc_preadb(pattern + 1, module + offset + TC_PATTERN1);
58 		err |= tc_preadb(pattern + 2, module + offset + TC_PATTERN2);
59 		err |= tc_preadb(pattern + 3, module + offset + TC_PATTERN3);
60 		if (err)
61 			goto out_err;
62 
63 		if (pattern[0] != 0x55 || pattern[1] != 0x00 ||
64 		    pattern[2] != 0xaa || pattern[3] != 0xff) {
65 			offset = TC_NEWCARD;
66 
67 			err = 0;
68 			err |= tc_preadb(pattern + 0,
69 					 module + offset + TC_PATTERN0);
70 			err |= tc_preadb(pattern + 1,
71 					 module + offset + TC_PATTERN1);
72 			err |= tc_preadb(pattern + 2,
73 					 module + offset + TC_PATTERN2);
74 			err |= tc_preadb(pattern + 3,
75 					 module + offset + TC_PATTERN3);
76 			if (err)
77 				goto out_err;
78 		}
79 
80 		if (pattern[0] != 0x55 || pattern[1] != 0x00 ||
81 		    pattern[2] != 0xaa || pattern[3] != 0xff)
82 			goto out_err;
83 
84 		/* Found a board, allocate it an entry in the list */
85 		tdev = kzalloc(sizeof(*tdev), GFP_KERNEL);
86 		if (!tdev) {
87 			pr_err("tc%x: unable to allocate tc_dev\n", slot);
88 			goto out_err;
89 		}
90 		dev_set_name(&tdev->dev, "tc%x", slot);
91 		tdev->bus = tbus;
92 		tdev->dev.parent = &tbus->dev;
93 		tdev->dev.bus = &tc_bus_type;
94 		tdev->slot = slot;
95 
96 		/* TURBOchannel has 34-bit DMA addressing (16GiB space). */
97 		tdev->dma_mask = DMA_BIT_MASK(34);
98 		tdev->dev.dma_mask = &tdev->dma_mask;
99 		tdev->dev.coherent_dma_mask = DMA_BIT_MASK(34);
100 
101 		for (i = 0; i < 8; i++) {
102 			tdev->firmware[i] =
103 				readb(module + offset + TC_FIRM_VER + 4 * i);
104 			tdev->vendor[i] =
105 				readb(module + offset + TC_VENDOR + 4 * i);
106 			tdev->name[i] =
107 				readb(module + offset + TC_MODULE + 4 * i);
108 		}
109 		tdev->firmware[8] = 0;
110 		tdev->vendor[8] = 0;
111 		tdev->name[8] = 0;
112 
113 		pr_info("%s: %s %s %s\n", dev_name(&tdev->dev), tdev->vendor,
114 			tdev->name, tdev->firmware);
115 
116 		devsize = readb(module + offset + TC_SLOT_SIZE);
117 		devsize <<= 22;
118 		if (devsize <= slotsize) {
119 			tdev->resource.start = slotaddr;
120 			tdev->resource.end = slotaddr + devsize - 1;
121 		} else if (devsize <= extslotsize) {
122 			tdev->resource.start = extslotaddr;
123 			tdev->resource.end = extslotaddr + devsize - 1;
124 		} else {
125 			pr_err("%s: Cannot provide slot space "
126 			       "(%ldMiB required, up to %ldMiB supported)\n",
127 			       dev_name(&tdev->dev), (long)(devsize >> 20),
128 			       (long)(max(slotsize, extslotsize) >> 20));
129 			kfree(tdev);
130 			goto out_err;
131 		}
132 		tdev->resource.name = tdev->name;
133 		tdev->resource.flags = IORESOURCE_MEM;
134 
135 		tc_device_get_irq(tdev);
136 
137 		if (device_register(&tdev->dev)) {
138 			put_device(&tdev->dev);
139 			goto out_err;
140 		}
141 		list_add_tail(&tdev->node, &tbus->devices);
142 
143 out_err:
144 		iounmap(module);
145 	}
146 }
147 
148 /*
149  * The main entry.
150  */
151 static int __init tc_init(void)
152 {
153 	/* Initialize the TURBOchannel bus */
154 	if (tc_bus_get_info(&tc_bus))
155 		goto out_err;
156 
157 	INIT_LIST_HEAD(&tc_bus.devices);
158 	dev_set_name(&tc_bus.dev, "tc");
159 	if (device_register(&tc_bus.dev))
160 		goto out_err_device;
161 
162 	if (tc_bus.info.slot_size) {
163 		unsigned int tc_clock = tc_get_speed(&tc_bus) / 100000;
164 
165 		pr_info("tc: TURBOchannel rev. %d at %d.%d MHz "
166 			"(with%s parity)\n", tc_bus.info.revision,
167 			tc_clock / 10, tc_clock % 10,
168 			tc_bus.info.parity ? "" : "out");
169 
170 		tc_bus.resource[0].start = tc_bus.slot_base;
171 		tc_bus.resource[0].end = tc_bus.slot_base +
172 					 (tc_bus.info.slot_size << 20) *
173 					 tc_bus.num_tcslots - 1;
174 		tc_bus.resource[0].name = tc_bus.name;
175 		tc_bus.resource[0].flags = IORESOURCE_MEM;
176 		if (request_resource(&iomem_resource,
177 				     &tc_bus.resource[0]) < 0) {
178 			pr_err("tc: Cannot reserve resource\n");
179 			goto out_err_device;
180 		}
181 		if (tc_bus.ext_slot_size) {
182 			tc_bus.resource[1].start = tc_bus.ext_slot_base;
183 			tc_bus.resource[1].end = tc_bus.ext_slot_base +
184 						 tc_bus.ext_slot_size *
185 						 tc_bus.num_tcslots - 1;
186 			tc_bus.resource[1].name = tc_bus.name;
187 			tc_bus.resource[1].flags = IORESOURCE_MEM;
188 			if (request_resource(&iomem_resource,
189 					     &tc_bus.resource[1]) < 0) {
190 				pr_err("tc: Cannot reserve resource\n");
191 				goto out_err_resource;
192 			}
193 		}
194 
195 		tc_bus_add_devices(&tc_bus);
196 	}
197 
198 	return 0;
199 
200 out_err_resource:
201 	release_resource(&tc_bus.resource[0]);
202 out_err_device:
203 	put_device(&tc_bus.dev);
204 out_err:
205 	return 0;
206 }
207 
208 subsys_initcall(tc_init);
209