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 */
41static bool debug;
42static bool poll;
43static struct cpci_hp_controller_ops zt5550_hpc_ops;
44static struct cpci_hp_controller zt5550_hpc;
45
46/* Primary cPCI bus bridge device */
47static struct pci_dev *bus0_dev;
48static struct pci_bus *bus0;
49
50/* Host controller device */
51static struct pci_dev *hc_dev;
52
53/* Host controller register addresses */
54static void __iomem *hc_registers;
55static void __iomem *csr_hc_index;
56static void __iomem *csr_hc_data;
57static void __iomem *csr_int_status;
58static void __iomem *csr_int_mask;
59
60
61static 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
120exit_release_region:
121	release_mem_region(pci_resource_start(hc_dev, 1),
122			   pci_resource_len(hc_dev, 1));
123exit_disable_device:
124	pci_disable_device(hc_dev);
125	return ret;
126}
127
128static 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
140static 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
148static 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
162static 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
175static 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
188static 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;
246init_register_error:
247	cpci_hp_unregister_controller(&zt5550_hpc);
248init_hc_error:
249	err("status = %d", status);
250	zt5550_hc_cleanup();
251	return status;
252
253}
254
255static 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
264static 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};
268MODULE_DEVICE_TABLE(pci, zt5550_hc_pci_tbl);
269
270static 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
277static 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
293static void __exit
294zt5550_exit(void)
295{
296	pci_unregister_driver(&zt5550_hc_driver);
297	release_region(ENUM_PORT, 1);
298}
299
300module_init(zt5550_init);
301module_exit(zt5550_exit);
302
303MODULE_AUTHOR(DRIVER_AUTHOR);
304MODULE_DESCRIPTION(DRIVER_DESC);
305MODULE_LICENSE("GPL");
306module_param(debug, bool, 0644);
307MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
308module_param(poll, bool, 0644);
309MODULE_PARM_DESC(poll, "#ENUM polling mode enabled or not");
310