xref: /linux/drivers/pci/hotplug/cpci_hotplug_pci.c (revision 762f99f4f3cb41a775b5157dd761217beba65873)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * CompactPCI Hot Plug Driver PCI functions
4  *
5  * Copyright (C) 2002,2005 by SOMA Networks, Inc.
6  *
7  * All rights reserved.
8  *
9  * Send feedback to <scottm@somanetworks.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/pci.h>
15 #include <linux/pci_hotplug.h>
16 #include <linux/proc_fs.h>
17 #include "../pci.h"
18 #include "cpci_hotplug.h"
19 
20 #define MY_NAME	"cpci_hotplug"
21 
22 #define dbg(format, arg...)					\
23 	do {							\
24 		if (cpci_debug)					\
25 			printk(KERN_DEBUG "%s: " format "\n",	\
26 				MY_NAME, ## arg);		\
27 	} while (0)
28 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
29 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
30 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
31 
32 
cpci_get_attention_status(struct slot * slot)33 u8 cpci_get_attention_status(struct slot *slot)
34 {
35 	int hs_cap;
36 	u16 hs_csr;
37 
38 	hs_cap = pci_bus_find_capability(slot->bus,
39 					 slot->devfn,
40 					 PCI_CAP_ID_CHSWP);
41 	if (!hs_cap)
42 		return 0;
43 
44 	if (pci_bus_read_config_word(slot->bus,
45 				     slot->devfn,
46 				     hs_cap + 2,
47 				     &hs_csr))
48 		return 0;
49 
50 	return hs_csr & 0x0008 ? 1 : 0;
51 }
52 
cpci_set_attention_status(struct slot * slot,int status)53 int cpci_set_attention_status(struct slot *slot, int status)
54 {
55 	int hs_cap;
56 	u16 hs_csr;
57 
58 	hs_cap = pci_bus_find_capability(slot->bus,
59 					 slot->devfn,
60 					 PCI_CAP_ID_CHSWP);
61 	if (!hs_cap)
62 		return 0;
63 	if (pci_bus_read_config_word(slot->bus,
64 				     slot->devfn,
65 				     hs_cap + 2,
66 				     &hs_csr))
67 		return 0;
68 	if (status)
69 		hs_csr |= HS_CSR_LOO;
70 	else
71 		hs_csr &= ~HS_CSR_LOO;
72 	if (pci_bus_write_config_word(slot->bus,
73 				      slot->devfn,
74 				      hs_cap + 2,
75 				      hs_csr))
76 		return 0;
77 	return 1;
78 }
79 
cpci_get_hs_csr(struct slot * slot)80 u16 cpci_get_hs_csr(struct slot *slot)
81 {
82 	int hs_cap;
83 	u16 hs_csr;
84 
85 	hs_cap = pci_bus_find_capability(slot->bus,
86 					 slot->devfn,
87 					 PCI_CAP_ID_CHSWP);
88 	if (!hs_cap)
89 		return 0xFFFF;
90 	if (pci_bus_read_config_word(slot->bus,
91 				     slot->devfn,
92 				     hs_cap + 2,
93 				     &hs_csr))
94 		return 0xFFFF;
95 	return hs_csr;
96 }
97 
cpci_check_and_clear_ins(struct slot * slot)98 int cpci_check_and_clear_ins(struct slot *slot)
99 {
100 	int hs_cap;
101 	u16 hs_csr;
102 	int ins = 0;
103 
104 	hs_cap = pci_bus_find_capability(slot->bus,
105 					 slot->devfn,
106 					 PCI_CAP_ID_CHSWP);
107 	if (!hs_cap)
108 		return 0;
109 	if (pci_bus_read_config_word(slot->bus,
110 				     slot->devfn,
111 				     hs_cap + 2,
112 				     &hs_csr))
113 		return 0;
114 	if (hs_csr & HS_CSR_INS) {
115 		/* Clear INS (by setting it) */
116 		if (pci_bus_write_config_word(slot->bus,
117 					      slot->devfn,
118 					      hs_cap + 2,
119 					      hs_csr))
120 			ins = 0;
121 		else
122 			ins = 1;
123 	}
124 	return ins;
125 }
126 
cpci_check_ext(struct slot * slot)127 int cpci_check_ext(struct slot *slot)
128 {
129 	int hs_cap;
130 	u16 hs_csr;
131 	int ext = 0;
132 
133 	hs_cap = pci_bus_find_capability(slot->bus,
134 					 slot->devfn,
135 					 PCI_CAP_ID_CHSWP);
136 	if (!hs_cap)
137 		return 0;
138 	if (pci_bus_read_config_word(slot->bus,
139 				     slot->devfn,
140 				     hs_cap + 2,
141 				     &hs_csr))
142 		return 0;
143 	if (hs_csr & HS_CSR_EXT)
144 		ext = 1;
145 	return ext;
146 }
147 
cpci_clear_ext(struct slot * slot)148 int cpci_clear_ext(struct slot *slot)
149 {
150 	int hs_cap;
151 	u16 hs_csr;
152 
153 	hs_cap = pci_bus_find_capability(slot->bus,
154 					 slot->devfn,
155 					 PCI_CAP_ID_CHSWP);
156 	if (!hs_cap)
157 		return -ENODEV;
158 	if (pci_bus_read_config_word(slot->bus,
159 				     slot->devfn,
160 				     hs_cap + 2,
161 				     &hs_csr))
162 		return -ENODEV;
163 	if (hs_csr & HS_CSR_EXT) {
164 		/* Clear EXT (by setting it) */
165 		if (pci_bus_write_config_word(slot->bus,
166 					      slot->devfn,
167 					      hs_cap + 2,
168 					      hs_csr))
169 			return -ENODEV;
170 	}
171 	return 0;
172 }
173 
cpci_led_on(struct slot * slot)174 int cpci_led_on(struct slot *slot)
175 {
176 	int hs_cap;
177 	u16 hs_csr;
178 
179 	hs_cap = pci_bus_find_capability(slot->bus,
180 					 slot->devfn,
181 					 PCI_CAP_ID_CHSWP);
182 	if (!hs_cap)
183 		return -ENODEV;
184 	if (pci_bus_read_config_word(slot->bus,
185 				     slot->devfn,
186 				     hs_cap + 2,
187 				     &hs_csr))
188 		return -ENODEV;
189 	if ((hs_csr & HS_CSR_LOO) != HS_CSR_LOO) {
190 		hs_csr |= HS_CSR_LOO;
191 		if (pci_bus_write_config_word(slot->bus,
192 					      slot->devfn,
193 					      hs_cap + 2,
194 					      hs_csr)) {
195 			err("Could not set LOO for slot %s", slot_name(slot));
196 			return -ENODEV;
197 		}
198 	}
199 	return 0;
200 }
201 
cpci_led_off(struct slot * slot)202 int cpci_led_off(struct slot *slot)
203 {
204 	int hs_cap;
205 	u16 hs_csr;
206 
207 	hs_cap = pci_bus_find_capability(slot->bus,
208 					 slot->devfn,
209 					 PCI_CAP_ID_CHSWP);
210 	if (!hs_cap)
211 		return -ENODEV;
212 	if (pci_bus_read_config_word(slot->bus,
213 				     slot->devfn,
214 				     hs_cap + 2,
215 				     &hs_csr))
216 		return -ENODEV;
217 	if (hs_csr & HS_CSR_LOO) {
218 		hs_csr &= ~HS_CSR_LOO;
219 		if (pci_bus_write_config_word(slot->bus,
220 					      slot->devfn,
221 					      hs_cap + 2,
222 					      hs_csr)) {
223 			err("Could not clear LOO for slot %s", slot_name(slot));
224 			return -ENODEV;
225 		}
226 	}
227 	return 0;
228 }
229 
230 
231 /*
232  * Device configuration functions
233  */
234 
cpci_configure_slot(struct slot * slot)235 int cpci_configure_slot(struct slot *slot)
236 {
237 	struct pci_dev *dev;
238 	struct pci_bus *parent;
239 	int ret = 0;
240 
241 	dbg("%s - enter", __func__);
242 
243 	pci_lock_rescan_remove();
244 
245 	if (slot->dev == NULL) {
246 		dbg("pci_dev null, finding %02x:%02x:%x",
247 		    slot->bus->number, PCI_SLOT(slot->devfn), PCI_FUNC(slot->devfn));
248 		slot->dev = pci_get_slot(slot->bus, slot->devfn);
249 	}
250 
251 	/* Still NULL? Well then scan for it! */
252 	if (slot->dev == NULL) {
253 		int n;
254 		dbg("pci_dev still null");
255 
256 		/*
257 		 * This will generate pci_dev structures for all functions, but
258 		 * we will only call this case when lookup fails.
259 		 */
260 		n = pci_scan_slot(slot->bus, slot->devfn);
261 		dbg("%s: pci_scan_slot returned %d", __func__, n);
262 		slot->dev = pci_get_slot(slot->bus, slot->devfn);
263 		if (slot->dev == NULL) {
264 			err("Could not find PCI device for slot %02x", slot->number);
265 			ret = -ENODEV;
266 			goto out;
267 		}
268 	}
269 	parent = slot->dev->bus;
270 
271 	for_each_pci_bridge(dev, parent) {
272 		if (PCI_SLOT(dev->devfn) == PCI_SLOT(slot->devfn))
273 			pci_hp_add_bridge(dev);
274 	}
275 
276 	pci_assign_unassigned_bridge_resources(parent->self);
277 
278 	pci_bus_add_devices(parent);
279 
280  out:
281 	pci_unlock_rescan_remove();
282 	dbg("%s - exit", __func__);
283 	return ret;
284 }
285 
cpci_unconfigure_slot(struct slot * slot)286 int cpci_unconfigure_slot(struct slot *slot)
287 {
288 	struct pci_dev *dev, *temp;
289 
290 	dbg("%s - enter", __func__);
291 	if (!slot->dev) {
292 		err("No device for slot %02x\n", slot->number);
293 		return -ENODEV;
294 	}
295 
296 	pci_lock_rescan_remove();
297 
298 	list_for_each_entry_safe(dev, temp, &slot->bus->devices, bus_list) {
299 		if (PCI_SLOT(dev->devfn) != PCI_SLOT(slot->devfn))
300 			continue;
301 		pci_dev_get(dev);
302 		pci_stop_and_remove_bus_device(dev);
303 		pci_dev_put(dev);
304 	}
305 	pci_dev_put(slot->dev);
306 	slot->dev = NULL;
307 
308 	pci_unlock_rescan_remove();
309 
310 	dbg("%s - exit", __func__);
311 	return 0;
312 }
313