xref: /linux/drivers/rapidio/switches/idt_gen3.c (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * IDT RXS Gen.3 Serial RapidIO switch family support
4  *
5  * Copyright 2016 Integrated Device Technology, Inc.
6  */
7 
8 #include <linux/stat.h>
9 #include <linux/module.h>
10 #include <linux/rio.h>
11 #include <linux/rio_drv.h>
12 #include <linux/rio_ids.h>
13 #include <linux/delay.h>
14 
15 #include <asm/page.h>
16 #include "../rio.h"
17 
18 #define RIO_EM_PW_STAT		0x40020
19 #define RIO_PW_CTL		0x40204
20 #define RIO_PW_CTL_PW_TMR		0xffffff00
21 #define RIO_PW_ROUTE		0x40208
22 
23 #define RIO_EM_DEV_INT_EN	0x40030
24 
25 #define RIO_PLM_SPx_IMP_SPEC_CTL(x)	(0x10100 + (x)*0x100)
26 #define RIO_PLM_SPx_IMP_SPEC_CTL_SOFT_RST	0x02000000
27 
28 #define RIO_PLM_SPx_PW_EN(x)	(0x10118 + (x)*0x100)
29 #define RIO_PLM_SPx_PW_EN_OK2U	0x40000000
30 #define RIO_PLM_SPx_PW_EN_LINIT 0x10000000
31 
32 #define RIO_BC_L2_Gn_ENTRYx_CSR(n, x)	(0x31000 + (n)*0x400 + (x)*0x4)
33 #define RIO_SPx_L2_Gn_ENTRYy_CSR(x, n, y) \
34 				(0x51000 + (x)*0x2000 + (n)*0x400 + (y)*0x4)
35 
36 static int
idtg3_route_add_entry(struct rio_mport * mport,u16 destid,u8 hopcount,u16 table,u16 route_destid,u8 route_port)37 idtg3_route_add_entry(struct rio_mport *mport, u16 destid, u8 hopcount,
38 		       u16 table, u16 route_destid, u8 route_port)
39 {
40 	u32 rval;
41 	u32 entry = route_port;
42 	int err = 0;
43 
44 	pr_debug("RIO: %s t=0x%x did_%x to p_%x\n",
45 		 __func__, table, route_destid, entry);
46 
47 	if (route_destid > 0xFF)
48 		return -EINVAL;
49 
50 	if (route_port == RIO_INVALID_ROUTE)
51 		entry = RIO_RT_ENTRY_DROP_PKT;
52 
53 	if (table == RIO_GLOBAL_TABLE) {
54 		/* Use broadcast register to update all per-port tables */
55 		err = rio_mport_write_config_32(mport, destid, hopcount,
56 				RIO_BC_L2_Gn_ENTRYx_CSR(0, route_destid),
57 				entry);
58 		return err;
59 	}
60 
61 	/*
62 	 * Verify that specified port/table number is valid
63 	 */
64 	err = rio_mport_read_config_32(mport, destid, hopcount,
65 				       RIO_SWP_INFO_CAR, &rval);
66 	if (err)
67 		return err;
68 
69 	if (table >= RIO_GET_TOTAL_PORTS(rval))
70 		return -EINVAL;
71 
72 	err = rio_mport_write_config_32(mport, destid, hopcount,
73 			RIO_SPx_L2_Gn_ENTRYy_CSR(table, 0, route_destid),
74 			entry);
75 	return err;
76 }
77 
78 static int
idtg3_route_get_entry(struct rio_mport * mport,u16 destid,u8 hopcount,u16 table,u16 route_destid,u8 * route_port)79 idtg3_route_get_entry(struct rio_mport *mport, u16 destid, u8 hopcount,
80 		       u16 table, u16 route_destid, u8 *route_port)
81 {
82 	u32 rval;
83 	int err;
84 
85 	if (route_destid > 0xFF)
86 		return -EINVAL;
87 
88 	err = rio_mport_read_config_32(mport, destid, hopcount,
89 				       RIO_SWP_INFO_CAR, &rval);
90 	if (err)
91 		return err;
92 
93 	/*
94 	 * This switch device does not have the dedicated global routing table.
95 	 * It is substituted by reading routing table of the ingress port of
96 	 * maintenance read requests.
97 	 */
98 	if (table == RIO_GLOBAL_TABLE)
99 		table = RIO_GET_PORT_NUM(rval);
100 	else if (table >= RIO_GET_TOTAL_PORTS(rval))
101 		return -EINVAL;
102 
103 	err = rio_mport_read_config_32(mport, destid, hopcount,
104 			RIO_SPx_L2_Gn_ENTRYy_CSR(table, 0, route_destid),
105 			&rval);
106 	if (err)
107 		return err;
108 
109 	if (rval == RIO_RT_ENTRY_DROP_PKT)
110 		*route_port = RIO_INVALID_ROUTE;
111 	else
112 		*route_port = (u8)rval;
113 
114 	return 0;
115 }
116 
117 static int
idtg3_route_clr_table(struct rio_mport * mport,u16 destid,u8 hopcount,u16 table)118 idtg3_route_clr_table(struct rio_mport *mport, u16 destid, u8 hopcount,
119 		       u16 table)
120 {
121 	u32 i;
122 	u32 rval;
123 	int err;
124 
125 	if (table == RIO_GLOBAL_TABLE) {
126 		for (i = 0; i <= 0xff; i++) {
127 			err = rio_mport_write_config_32(mport, destid, hopcount,
128 						RIO_BC_L2_Gn_ENTRYx_CSR(0, i),
129 						RIO_RT_ENTRY_DROP_PKT);
130 			if (err)
131 				break;
132 		}
133 
134 		return err;
135 	}
136 
137 	err = rio_mport_read_config_32(mport, destid, hopcount,
138 				       RIO_SWP_INFO_CAR, &rval);
139 	if (err)
140 		return err;
141 
142 	if (table >= RIO_GET_TOTAL_PORTS(rval))
143 		return -EINVAL;
144 
145 	for (i = 0; i <= 0xff; i++) {
146 		err = rio_mport_write_config_32(mport, destid, hopcount,
147 					RIO_SPx_L2_Gn_ENTRYy_CSR(table, 0, i),
148 					RIO_RT_ENTRY_DROP_PKT);
149 		if (err)
150 			break;
151 	}
152 
153 	return err;
154 }
155 
156 /*
157  * This routine performs device-specific initialization only.
158  * All standard EM configuration should be performed at upper level.
159  */
160 static int
idtg3_em_init(struct rio_dev * rdev)161 idtg3_em_init(struct rio_dev *rdev)
162 {
163 	int i, tmp;
164 	u32 rval;
165 
166 	pr_debug("RIO: %s [%d:%d]\n", __func__, rdev->destid, rdev->hopcount);
167 
168 	/* Disable assertion of interrupt signal */
169 	rio_write_config_32(rdev, RIO_EM_DEV_INT_EN, 0);
170 
171 	/* Disable port-write event notifications during initialization */
172 	rio_write_config_32(rdev, rdev->em_efptr + RIO_EM_PW_TX_CTRL,
173 			    RIO_EM_PW_TX_CTRL_PW_DIS);
174 
175 	/* Configure Port-Write notifications for hot-swap events */
176 	tmp = RIO_GET_TOTAL_PORTS(rdev->swpinfo);
177 	for (i = 0; i < tmp; i++) {
178 
179 		rio_read_config_32(rdev,
180 			RIO_DEV_PORT_N_ERR_STS_CSR(rdev, i),
181 			&rval);
182 		if (rval & RIO_PORT_N_ERR_STS_PORT_UA)
183 			continue;
184 
185 		/* Clear events signaled before enabling notification */
186 		rio_write_config_32(rdev,
187 			rdev->em_efptr + RIO_EM_PN_ERR_DETECT(i), 0);
188 
189 		/* Enable event notifications */
190 		rio_write_config_32(rdev,
191 			rdev->em_efptr + RIO_EM_PN_ERRRATE_EN(i),
192 			RIO_EM_PN_ERRRATE_EN_OK2U | RIO_EM_PN_ERRRATE_EN_U2OK);
193 		/* Enable port-write generation on events */
194 		rio_write_config_32(rdev, RIO_PLM_SPx_PW_EN(i),
195 			RIO_PLM_SPx_PW_EN_OK2U | RIO_PLM_SPx_PW_EN_LINIT);
196 
197 	}
198 
199 	/* Set Port-Write destination port */
200 	tmp = RIO_GET_PORT_NUM(rdev->swpinfo);
201 	rio_write_config_32(rdev, RIO_PW_ROUTE, 1 << tmp);
202 
203 
204 	/* Enable sending port-write event notifications */
205 	rio_write_config_32(rdev, rdev->em_efptr + RIO_EM_PW_TX_CTRL, 0);
206 
207 	/* set TVAL = ~50us */
208 	rio_write_config_32(rdev,
209 		rdev->phys_efptr + RIO_PORT_LINKTO_CTL_CSR, 0x8e << 8);
210 	return 0;
211 }
212 
213 
214 /*
215  * idtg3_em_handler - device-specific error handler
216  *
217  * If the link is down (PORT_UNINIT) does nothing - this is considered
218  * as link partner removal from the port.
219  *
220  * If the link is up (PORT_OK) - situation is handled as *new* device insertion.
221  * In this case ERR_STOP bits are cleared by issuing soft reset command to the
222  * reporting port. Inbound and outbound ackIDs are cleared by the reset as well.
223  * This way the port is synchronized with freshly inserted device (assuming it
224  * was reset/powered-up on insertion).
225  *
226  * TODO: This is not sufficient in a situation when a link between two devices
227  * was down and up again (e.g. cable disconnect). For that situation full ackID
228  * realignment process has to be implemented.
229  */
230 static int
idtg3_em_handler(struct rio_dev * rdev,u8 pnum)231 idtg3_em_handler(struct rio_dev *rdev, u8 pnum)
232 {
233 	u32 err_status;
234 	u32 rval;
235 
236 	rio_read_config_32(rdev,
237 			RIO_DEV_PORT_N_ERR_STS_CSR(rdev, pnum),
238 			&err_status);
239 
240 	/* Do nothing for device/link removal */
241 	if (err_status & RIO_PORT_N_ERR_STS_PORT_UNINIT)
242 		return 0;
243 
244 	/* When link is OK we have a device insertion.
245 	 * Request port soft reset to clear errors if they present.
246 	 * Inbound and outbound ackIDs will be 0 after reset.
247 	 */
248 	if (err_status & (RIO_PORT_N_ERR_STS_OUT_ES |
249 				RIO_PORT_N_ERR_STS_INP_ES)) {
250 		rio_read_config_32(rdev, RIO_PLM_SPx_IMP_SPEC_CTL(pnum), &rval);
251 		rio_write_config_32(rdev, RIO_PLM_SPx_IMP_SPEC_CTL(pnum),
252 				    rval | RIO_PLM_SPx_IMP_SPEC_CTL_SOFT_RST);
253 		udelay(10);
254 		rio_write_config_32(rdev, RIO_PLM_SPx_IMP_SPEC_CTL(pnum), rval);
255 		msleep(500);
256 	}
257 
258 	return 0;
259 }
260 
261 static struct rio_switch_ops idtg3_switch_ops = {
262 	.owner = THIS_MODULE,
263 	.add_entry = idtg3_route_add_entry,
264 	.get_entry = idtg3_route_get_entry,
265 	.clr_table = idtg3_route_clr_table,
266 	.em_init   = idtg3_em_init,
267 	.em_handle = idtg3_em_handler,
268 };
269 
idtg3_probe(struct rio_dev * rdev,const struct rio_device_id * id)270 static int idtg3_probe(struct rio_dev *rdev, const struct rio_device_id *id)
271 {
272 	pr_debug("RIO: %s for %s\n", __func__, rio_name(rdev));
273 
274 	spin_lock(&rdev->rswitch->lock);
275 
276 	if (rdev->rswitch->ops) {
277 		spin_unlock(&rdev->rswitch->lock);
278 		return -EINVAL;
279 	}
280 
281 	rdev->rswitch->ops = &idtg3_switch_ops;
282 
283 	if (rdev->do_enum) {
284 		/* Disable hierarchical routing support: Existing fabric
285 		 * enumeration/discovery process (see rio-scan.c) uses 8-bit
286 		 * flat destination ID routing only.
287 		 */
288 		rio_write_config_32(rdev, 0x5000 + RIO_BC_RT_CTL_CSR, 0);
289 	}
290 
291 	spin_unlock(&rdev->rswitch->lock);
292 
293 	return 0;
294 }
295 
idtg3_remove(struct rio_dev * rdev)296 static void idtg3_remove(struct rio_dev *rdev)
297 {
298 	pr_debug("RIO: %s for %s\n", __func__, rio_name(rdev));
299 	spin_lock(&rdev->rswitch->lock);
300 	if (rdev->rswitch->ops == &idtg3_switch_ops)
301 		rdev->rswitch->ops = NULL;
302 	spin_unlock(&rdev->rswitch->lock);
303 }
304 
305 /*
306  * Gen3 switches repeat sending PW messages until a corresponding event flag
307  * is cleared. Use shutdown notification to disable generation of port-write
308  * messages if their destination node is shut down.
309  */
idtg3_shutdown(struct rio_dev * rdev)310 static void idtg3_shutdown(struct rio_dev *rdev)
311 {
312 	int i;
313 	u32 rval;
314 	u16 destid;
315 
316 	/* Currently the enumerator node acts also as PW handler */
317 	if (!rdev->do_enum)
318 		return;
319 
320 	pr_debug("RIO: %s(%s)\n", __func__, rio_name(rdev));
321 
322 	rio_read_config_32(rdev, RIO_PW_ROUTE, &rval);
323 	i = RIO_GET_PORT_NUM(rdev->swpinfo);
324 
325 	/* Check port-write destination port */
326 	if (!((1 << i) & rval))
327 		return;
328 
329 	/* Disable sending port-write event notifications if PW destID
330 	 * matches to one of the enumerator node
331 	 */
332 	rio_read_config_32(rdev, rdev->em_efptr + RIO_EM_PW_TGT_DEVID, &rval);
333 
334 	if (rval & RIO_EM_PW_TGT_DEVID_DEV16)
335 		destid = rval >> 16;
336 	else
337 		destid = ((rval & RIO_EM_PW_TGT_DEVID_D8) >> 16);
338 
339 	if (rdev->net->hport->host_deviceid == destid) {
340 		rio_write_config_32(rdev,
341 				    rdev->em_efptr + RIO_EM_PW_TX_CTRL, 0);
342 		pr_debug("RIO: %s(%s) PW transmission disabled\n",
343 			 __func__, rio_name(rdev));
344 	}
345 }
346 
347 static const struct rio_device_id idtg3_id_table[] = {
348 	{RIO_DEVICE(RIO_DID_IDTRXS1632, RIO_VID_IDT)},
349 	{RIO_DEVICE(RIO_DID_IDTRXS2448, RIO_VID_IDT)},
350 	{ 0, }	/* terminate list */
351 };
352 
353 static struct rio_driver idtg3_driver = {
354 	.name = "idt_gen3",
355 	.id_table = idtg3_id_table,
356 	.probe = idtg3_probe,
357 	.remove = idtg3_remove,
358 	.shutdown = idtg3_shutdown,
359 };
360 
idtg3_init(void)361 static int __init idtg3_init(void)
362 {
363 	return rio_register_driver(&idtg3_driver);
364 }
365 
idtg3_exit(void)366 static void __exit idtg3_exit(void)
367 {
368 	pr_debug("RIO: %s\n", __func__);
369 	rio_unregister_driver(&idtg3_driver);
370 	pr_debug("RIO: %s done\n", __func__);
371 }
372 
373 device_initcall(idtg3_init);
374 module_exit(idtg3_exit);
375 
376 MODULE_DESCRIPTION("IDT RXS Gen.3 Serial RapidIO switch family driver");
377 MODULE_AUTHOR("Integrated Device Technology, Inc.");
378 MODULE_LICENSE("GPL");
379