1 /*
2  * cpcihp_zt5550.c
3  *
4  * Intel/Ziatech ZT5550 CompactPCI Host Controller driver
5  *
6  * Copyright 2002 SOMA Networks, Inc.
7  * Copyright 2001 Intel San Luis Obispo
8  * Copyright 2000,2001 MontaVista Software Inc.
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License as published by the
12  * Free Software Foundation; either version 2 of the License, or (at your
13  * option) any later version.
14  *
15  * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
16  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
17  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
18  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
22  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * You should have received a copy of the GNU General Public License along
27  * with this program; if not, write to the Free Software Foundation, Inc.,
28  * 675 Mass Ave, Cambridge, MA 02139, USA.
29  *
30  * Send feedback to <scottm@somanetworks.com>
31  */
32 
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/init.h>
36 #include <linux/errno.h>
37 #include <linux/pci.h>
38 #include <linux/interrupt.h>
39 #include <linux/signal.h>	/* IRQF_SHARED */
40 #include "cpci_hotplug.h"
41 #include "cpcihp_zt5550.h"
42 
43 #define DRIVER_VERSION	"0.2"
44 #define DRIVER_AUTHOR	"Scott Murray <scottm@somanetworks.com>"
45 #define DRIVER_DESC	"ZT5550 CompactPCI Hot Plug Driver"
46 
47 #define MY_NAME	"cpcihp_zt5550"
48 
49 #define dbg(format, arg...)					\
50 	do {							\
51 		if (debug)					\
52 			printk(KERN_DEBUG "%s: " format "\n",	\
53 				MY_NAME, ## arg);		\
54 	} while (0)
55 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
56 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
57 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
58 
59 /* local variables */
60 static bool debug;
61 static bool poll;
62 static struct cpci_hp_controller_ops zt5550_hpc_ops;
63 static struct cpci_hp_controller zt5550_hpc;
64 
65 /* Primary cPCI bus bridge device */
66 static struct pci_dev *bus0_dev;
67 static struct pci_bus *bus0;
68 
69 /* Host controller device */
70 static struct pci_dev *hc_dev;
71 
72 /* Host controller register addresses */
73 static void __iomem *hc_registers;
74 static void __iomem *csr_hc_index;
75 static void __iomem *csr_hc_data;
76 static void __iomem *csr_int_status;
77 static void __iomem *csr_int_mask;
78 
79 
80 static int zt5550_hc_config(struct pci_dev *pdev)
81 {
82 	int ret;
83 
84 	/* Since we know that no boards exist with two HC chips, treat it as an error */
85 	if (hc_dev) {
86 		err("too many host controller devices?");
87 		return -EBUSY;
88 	}
89 
90 	ret = pci_enable_device(pdev);
91 	if (ret) {
92 		err("cannot enable %s\n", pci_name(pdev));
93 		return ret;
94 	}
95 
96 	hc_dev = pdev;
97 	dbg("hc_dev = %p", hc_dev);
98 	dbg("pci resource start %llx", (unsigned long long)pci_resource_start(hc_dev, 1));
99 	dbg("pci resource len %llx", (unsigned long long)pci_resource_len(hc_dev, 1));
100 
101 	if (!request_mem_region(pci_resource_start(hc_dev, 1),
102 				pci_resource_len(hc_dev, 1), MY_NAME)) {
103 		err("cannot reserve MMIO region");
104 		ret = -ENOMEM;
105 		goto exit_disable_device;
106 	}
107 
108 	hc_registers =
109 	    ioremap(pci_resource_start(hc_dev, 1), pci_resource_len(hc_dev, 1));
110 	if (!hc_registers) {
111 		err("cannot remap MMIO region %llx @ %llx",
112 			(unsigned long long)pci_resource_len(hc_dev, 1),
113 			(unsigned long long)pci_resource_start(hc_dev, 1));
114 		ret = -ENODEV;
115 		goto exit_release_region;
116 	}
117 
118 	csr_hc_index = hc_registers + CSR_HCINDEX;
119 	csr_hc_data = hc_registers + CSR_HCDATA;
120 	csr_int_status = hc_registers + CSR_INTSTAT;
121 	csr_int_mask = hc_registers + CSR_INTMASK;
122 
123 	/*
124 	 * Disable host control, fault and serial interrupts
125 	 */
126 	dbg("disabling host control, fault and serial interrupts");
127 	writeb((u8) HC_INT_MASK_REG, csr_hc_index);
128 	writeb((u8) ALL_INDEXED_INTS_MASK, csr_hc_data);
129 	dbg("disabled host control, fault and serial interrupts");
130 
131 	/*
132 	 * Disable timer0, timer1 and ENUM interrupts
133 	 */
134 	dbg("disabling timer0, timer1 and ENUM interrupts");
135 	writeb((u8) ALL_DIRECT_INTS_MASK, csr_int_mask);
136 	dbg("disabled timer0, timer1 and ENUM interrupts");
137 	return 0;
138 
139 exit_release_region:
140 	release_mem_region(pci_resource_start(hc_dev, 1),
141 			   pci_resource_len(hc_dev, 1));
142 exit_disable_device:
143 	pci_disable_device(hc_dev);
144 	return ret;
145 }
146 
147 static int zt5550_hc_cleanup(void)
148 {
149 	if (!hc_dev)
150 		return -ENODEV;
151 
152 	iounmap(hc_registers);
153 	release_mem_region(pci_resource_start(hc_dev, 1),
154 			   pci_resource_len(hc_dev, 1));
155 	pci_disable_device(hc_dev);
156 	return 0;
157 }
158 
159 static int zt5550_hc_query_enum(void)
160 {
161 	u8 value;
162 
163 	value = inb_p(ENUM_PORT);
164 	return ((value & ENUM_MASK) == ENUM_MASK);
165 }
166 
167 static int zt5550_hc_check_irq(void *dev_id)
168 {
169 	int ret;
170 	u8 reg;
171 
172 	ret = 0;
173 	if (dev_id == zt5550_hpc.dev_id) {
174 		reg = readb(csr_int_status);
175 		if (reg)
176 			ret = 1;
177 	}
178 	return ret;
179 }
180 
181 static int zt5550_hc_enable_irq(void)
182 {
183 	u8 reg;
184 
185 	if (hc_dev == NULL)
186 		return -ENODEV;
187 
188 	reg = readb(csr_int_mask);
189 	reg = reg & ~ENUM_INT_MASK;
190 	writeb(reg, csr_int_mask);
191 	return 0;
192 }
193 
194 static int zt5550_hc_disable_irq(void)
195 {
196 	u8 reg;
197 
198 	if (hc_dev == NULL)
199 		return -ENODEV;
200 
201 	reg = readb(csr_int_mask);
202 	reg = reg | ENUM_INT_MASK;
203 	writeb(reg, csr_int_mask);
204 	return 0;
205 }
206 
207 static int zt5550_hc_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
208 {
209 	int status;
210 
211 	status = zt5550_hc_config(pdev);
212 	if (status != 0)
213 		return status;
214 
215 	dbg("returned from zt5550_hc_config");
216 
217 	memset(&zt5550_hpc, 0, sizeof(struct cpci_hp_controller));
218 	zt5550_hpc_ops.query_enum = zt5550_hc_query_enum;
219 	zt5550_hpc.ops = &zt5550_hpc_ops;
220 	if (!poll) {
221 		zt5550_hpc.irq = hc_dev->irq;
222 		zt5550_hpc.irq_flags = IRQF_SHARED;
223 		zt5550_hpc.dev_id = hc_dev;
224 
225 		zt5550_hpc_ops.enable_irq = zt5550_hc_enable_irq;
226 		zt5550_hpc_ops.disable_irq = zt5550_hc_disable_irq;
227 		zt5550_hpc_ops.check_irq = zt5550_hc_check_irq;
228 	} else {
229 		info("using ENUM# polling mode");
230 	}
231 
232 	status = cpci_hp_register_controller(&zt5550_hpc);
233 	if (status != 0) {
234 		err("could not register cPCI hotplug controller");
235 		goto init_hc_error;
236 	}
237 	dbg("registered controller");
238 
239 	/* Look for first device matching cPCI bus's bridge vendor and device IDs */
240 	bus0_dev = pci_get_device(PCI_VENDOR_ID_DEC,
241 				  PCI_DEVICE_ID_DEC_21154, NULL);
242 	if (!bus0_dev) {
243 		status = -ENODEV;
244 		goto init_register_error;
245 	}
246 	bus0 = bus0_dev->subordinate;
247 	pci_dev_put(bus0_dev);
248 
249 	status = cpci_hp_register_bus(bus0, 0x0a, 0x0f);
250 	if (status != 0) {
251 		err("could not register cPCI hotplug bus");
252 		goto init_register_error;
253 	}
254 	dbg("registered bus");
255 
256 	status = cpci_hp_start();
257 	if (status != 0) {
258 		err("could not started cPCI hotplug system");
259 		cpci_hp_unregister_bus(bus0);
260 		goto init_register_error;
261 	}
262 	dbg("started cpci hp system");
263 
264 	return 0;
265 init_register_error:
266 	cpci_hp_unregister_controller(&zt5550_hpc);
267 init_hc_error:
268 	err("status = %d", status);
269 	zt5550_hc_cleanup();
270 	return status;
271 
272 }
273 
274 static void zt5550_hc_remove_one(struct pci_dev *pdev)
275 {
276 	cpci_hp_stop();
277 	cpci_hp_unregister_bus(bus0);
278 	cpci_hp_unregister_controller(&zt5550_hpc);
279 	zt5550_hc_cleanup();
280 }
281 
282 
283 static struct pci_device_id zt5550_hc_pci_tbl[] = {
284 	{ PCI_VENDOR_ID_ZIATECH, PCI_DEVICE_ID_ZIATECH_5550_HC, PCI_ANY_ID, PCI_ANY_ID, },
285 	{ 0, }
286 };
287 MODULE_DEVICE_TABLE(pci, zt5550_hc_pci_tbl);
288 
289 static struct pci_driver zt5550_hc_driver = {
290 	.name		= "zt5550_hc",
291 	.id_table	= zt5550_hc_pci_tbl,
292 	.probe		= zt5550_hc_init_one,
293 	.remove		= zt5550_hc_remove_one,
294 };
295 
296 static int __init zt5550_init(void)
297 {
298 	struct resource *r;
299 	int rc;
300 
301 	info(DRIVER_DESC " version: " DRIVER_VERSION);
302 	r = request_region(ENUM_PORT, 1, "#ENUM hotswap signal register");
303 	if (!r)
304 		return -EBUSY;
305 
306 	rc = pci_register_driver(&zt5550_hc_driver);
307 	if (rc < 0)
308 		release_region(ENUM_PORT, 1);
309 	return rc;
310 }
311 
312 static void __exit
313 zt5550_exit(void)
314 {
315 	pci_unregister_driver(&zt5550_hc_driver);
316 	release_region(ENUM_PORT, 1);
317 }
318 
319 module_init(zt5550_init);
320 module_exit(zt5550_exit);
321 
322 MODULE_AUTHOR(DRIVER_AUTHOR);
323 MODULE_DESCRIPTION(DRIVER_DESC);
324 MODULE_LICENSE("GPL");
325 module_param(debug, bool, 0644);
326 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
327 module_param(poll, bool, 0644);
328 MODULE_PARM_DESC(poll, "#ENUM polling mode enabled or not");
329