1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * cpcihp_zt5550.c
4  *
5  * Intel/Ziatech ZT5550 CompactPCI Host Controller driver
6  *
7  * Copyright 2002 SOMA Networks, Inc.
8  * Copyright 2001 Intel San Luis Obispo
9  * Copyright 2000,2001 MontaVista Software Inc.
10  *
11  * Send feedback to <scottm@somanetworks.com>
12  */
13 
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/init.h>
17 #include <linux/errno.h>
18 #include <linux/pci.h>
19 #include <linux/interrupt.h>
20 #include <linux/signal.h>	/* IRQF_SHARED */
21 #include "cpci_hotplug.h"
22 #include "cpcihp_zt5550.h"
23 
24 #define DRIVER_VERSION	"0.2"
25 #define DRIVER_AUTHOR	"Scott Murray <scottm@somanetworks.com>"
26 #define DRIVER_DESC	"ZT5550 CompactPCI Hot Plug Driver"
27 
28 #define MY_NAME	"cpcihp_zt5550"
29 
30 #define dbg(format, arg...)					\
31 	do {							\
32 		if (debug)					\
33 			printk(KERN_DEBUG "%s: " format "\n",	\
34 				MY_NAME, ## arg);		\
35 	} while (0)
36 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
37 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
38 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
39 
40 /* local variables */
41 static bool debug;
42 static bool poll;
43 static struct cpci_hp_controller_ops zt5550_hpc_ops;
44 static struct cpci_hp_controller zt5550_hpc;
45 
46 /* Primary cPCI bus bridge device */
47 static struct pci_dev *bus0_dev;
48 static struct pci_bus *bus0;
49 
50 /* Host controller device */
51 static struct pci_dev *hc_dev;
52 
53 /* Host controller register addresses */
54 static void __iomem *hc_registers;
55 static void __iomem *csr_hc_index;
56 static void __iomem *csr_hc_data;
57 static void __iomem *csr_int_status;
58 static void __iomem *csr_int_mask;
59 
60 
61 static int zt5550_hc_config(struct pci_dev *pdev)
62 {
63 	int ret;
64 
65 	/* Since we know that no boards exist with two HC chips, treat it as an error */
66 	if (hc_dev) {
67 		err("too many host controller devices?");
68 		return -EBUSY;
69 	}
70 
71 	ret = pci_enable_device(pdev);
72 	if (ret) {
73 		err("cannot enable %s\n", pci_name(pdev));
74 		return ret;
75 	}
76 
77 	hc_dev = pdev;
78 	dbg("hc_dev = %p", hc_dev);
79 	dbg("pci resource start %llx", (unsigned long long)pci_resource_start(hc_dev, 1));
80 	dbg("pci resource len %llx", (unsigned long long)pci_resource_len(hc_dev, 1));
81 
82 	if (!request_mem_region(pci_resource_start(hc_dev, 1),
83 				pci_resource_len(hc_dev, 1), MY_NAME)) {
84 		err("cannot reserve MMIO region");
85 		ret = -ENOMEM;
86 		goto exit_disable_device;
87 	}
88 
89 	hc_registers =
90 	    ioremap(pci_resource_start(hc_dev, 1), pci_resource_len(hc_dev, 1));
91 	if (!hc_registers) {
92 		err("cannot remap MMIO region %llx @ %llx",
93 			(unsigned long long)pci_resource_len(hc_dev, 1),
94 			(unsigned long long)pci_resource_start(hc_dev, 1));
95 		ret = -ENODEV;
96 		goto exit_release_region;
97 	}
98 
99 	csr_hc_index = hc_registers + CSR_HCINDEX;
100 	csr_hc_data = hc_registers + CSR_HCDATA;
101 	csr_int_status = hc_registers + CSR_INTSTAT;
102 	csr_int_mask = hc_registers + CSR_INTMASK;
103 
104 	/*
105 	 * Disable host control, fault and serial interrupts
106 	 */
107 	dbg("disabling host control, fault and serial interrupts");
108 	writeb((u8) HC_INT_MASK_REG, csr_hc_index);
109 	writeb((u8) ALL_INDEXED_INTS_MASK, csr_hc_data);
110 	dbg("disabled host control, fault and serial interrupts");
111 
112 	/*
113 	 * Disable timer0, timer1 and ENUM interrupts
114 	 */
115 	dbg("disabling timer0, timer1 and ENUM interrupts");
116 	writeb((u8) ALL_DIRECT_INTS_MASK, csr_int_mask);
117 	dbg("disabled timer0, timer1 and ENUM interrupts");
118 	return 0;
119 
120 exit_release_region:
121 	release_mem_region(pci_resource_start(hc_dev, 1),
122 			   pci_resource_len(hc_dev, 1));
123 exit_disable_device:
124 	pci_disable_device(hc_dev);
125 	return ret;
126 }
127 
128 static int zt5550_hc_cleanup(void)
129 {
130 	if (!hc_dev)
131 		return -ENODEV;
132 
133 	iounmap(hc_registers);
134 	release_mem_region(pci_resource_start(hc_dev, 1),
135 			   pci_resource_len(hc_dev, 1));
136 	pci_disable_device(hc_dev);
137 	return 0;
138 }
139 
140 static int zt5550_hc_query_enum(void)
141 {
142 	u8 value;
143 
144 	value = inb_p(ENUM_PORT);
145 	return ((value & ENUM_MASK) == ENUM_MASK);
146 }
147 
148 static int zt5550_hc_check_irq(void *dev_id)
149 {
150 	int ret;
151 	u8 reg;
152 
153 	ret = 0;
154 	if (dev_id == zt5550_hpc.dev_id) {
155 		reg = readb(csr_int_status);
156 		if (reg)
157 			ret = 1;
158 	}
159 	return ret;
160 }
161 
162 static int zt5550_hc_enable_irq(void)
163 {
164 	u8 reg;
165 
166 	if (hc_dev == NULL)
167 		return -ENODEV;
168 
169 	reg = readb(csr_int_mask);
170 	reg = reg & ~ENUM_INT_MASK;
171 	writeb(reg, csr_int_mask);
172 	return 0;
173 }
174 
175 static int zt5550_hc_disable_irq(void)
176 {
177 	u8 reg;
178 
179 	if (hc_dev == NULL)
180 		return -ENODEV;
181 
182 	reg = readb(csr_int_mask);
183 	reg = reg | ENUM_INT_MASK;
184 	writeb(reg, csr_int_mask);
185 	return 0;
186 }
187 
188 static int zt5550_hc_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
189 {
190 	int status;
191 
192 	status = zt5550_hc_config(pdev);
193 	if (status != 0)
194 		return status;
195 
196 	dbg("returned from zt5550_hc_config");
197 
198 	memset(&zt5550_hpc, 0, sizeof(struct cpci_hp_controller));
199 	zt5550_hpc_ops.query_enum = zt5550_hc_query_enum;
200 	zt5550_hpc.ops = &zt5550_hpc_ops;
201 	if (!poll) {
202 		zt5550_hpc.irq = hc_dev->irq;
203 		zt5550_hpc.irq_flags = IRQF_SHARED;
204 		zt5550_hpc.dev_id = hc_dev;
205 
206 		zt5550_hpc_ops.enable_irq = zt5550_hc_enable_irq;
207 		zt5550_hpc_ops.disable_irq = zt5550_hc_disable_irq;
208 		zt5550_hpc_ops.check_irq = zt5550_hc_check_irq;
209 	} else {
210 		info("using ENUM# polling mode");
211 	}
212 
213 	status = cpci_hp_register_controller(&zt5550_hpc);
214 	if (status != 0) {
215 		err("could not register cPCI hotplug controller");
216 		goto init_hc_error;
217 	}
218 	dbg("registered controller");
219 
220 	/* Look for first device matching cPCI bus's bridge vendor and device IDs */
221 	bus0_dev = pci_get_device(PCI_VENDOR_ID_DEC,
222 				  PCI_DEVICE_ID_DEC_21154, NULL);
223 	if (!bus0_dev) {
224 		status = -ENODEV;
225 		goto init_register_error;
226 	}
227 	bus0 = bus0_dev->subordinate;
228 	pci_dev_put(bus0_dev);
229 
230 	status = cpci_hp_register_bus(bus0, 0x0a, 0x0f);
231 	if (status != 0) {
232 		err("could not register cPCI hotplug bus");
233 		goto init_register_error;
234 	}
235 	dbg("registered bus");
236 
237 	status = cpci_hp_start();
238 	if (status != 0) {
239 		err("could not started cPCI hotplug system");
240 		cpci_hp_unregister_bus(bus0);
241 		goto init_register_error;
242 	}
243 	dbg("started cpci hp system");
244 
245 	return 0;
246 init_register_error:
247 	cpci_hp_unregister_controller(&zt5550_hpc);
248 init_hc_error:
249 	err("status = %d", status);
250 	zt5550_hc_cleanup();
251 	return status;
252 
253 }
254 
255 static void zt5550_hc_remove_one(struct pci_dev *pdev)
256 {
257 	cpci_hp_stop();
258 	cpci_hp_unregister_bus(bus0);
259 	cpci_hp_unregister_controller(&zt5550_hpc);
260 	zt5550_hc_cleanup();
261 }
262 
263 
264 static const struct pci_device_id zt5550_hc_pci_tbl[] = {
265 	{ PCI_VENDOR_ID_ZIATECH, PCI_DEVICE_ID_ZIATECH_5550_HC, PCI_ANY_ID, PCI_ANY_ID, },
266 	{ 0, }
267 };
268 MODULE_DEVICE_TABLE(pci, zt5550_hc_pci_tbl);
269 
270 static struct pci_driver zt5550_hc_driver = {
271 	.name		= "zt5550_hc",
272 	.id_table	= zt5550_hc_pci_tbl,
273 	.probe		= zt5550_hc_init_one,
274 	.remove		= zt5550_hc_remove_one,
275 };
276 
277 static int __init zt5550_init(void)
278 {
279 	struct resource *r;
280 	int rc;
281 
282 	info(DRIVER_DESC " version: " DRIVER_VERSION);
283 	r = request_region(ENUM_PORT, 1, "#ENUM hotswap signal register");
284 	if (!r)
285 		return -EBUSY;
286 
287 	rc = pci_register_driver(&zt5550_hc_driver);
288 	if (rc < 0)
289 		release_region(ENUM_PORT, 1);
290 	return rc;
291 }
292 
293 static void __exit
294 zt5550_exit(void)
295 {
296 	pci_unregister_driver(&zt5550_hc_driver);
297 	release_region(ENUM_PORT, 1);
298 }
299 
300 module_init(zt5550_init);
301 module_exit(zt5550_exit);
302 
303 MODULE_AUTHOR(DRIVER_AUTHOR);
304 MODULE_DESCRIPTION(DRIVER_DESC);
305 MODULE_LICENSE("GPL");
306 module_param(debug, bool, 0644);
307 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
308 module_param(poll, bool, 0644);
309 MODULE_PARM_DESC(poll, "#ENUM polling mode enabled or not");
310