x86/unwinder: Handle stack overflows more gracefully
[linux/fpc-iii.git] / drivers / rapidio / switches / idt_gen3.c
blobc5923a547bedb6d674c5aba84673086020f97a5c
1 /*
2 * IDT RXS Gen.3 Serial RapidIO switch family support
4 * Copyright 2016 Integrated Device Technology, Inc.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
12 #include <linux/stat.h>
13 #include <linux/module.h>
14 #include <linux/rio.h>
15 #include <linux/rio_drv.h>
16 #include <linux/rio_ids.h>
17 #include <linux/delay.h>
19 #include <asm/page.h>
20 #include "../rio.h"
22 #define RIO_EM_PW_STAT 0x40020
23 #define RIO_PW_CTL 0x40204
24 #define RIO_PW_CTL_PW_TMR 0xffffff00
25 #define RIO_PW_ROUTE 0x40208
27 #define RIO_EM_DEV_INT_EN 0x40030
29 #define RIO_PLM_SPx_IMP_SPEC_CTL(x) (0x10100 + (x)*0x100)
30 #define RIO_PLM_SPx_IMP_SPEC_CTL_SOFT_RST 0x02000000
32 #define RIO_PLM_SPx_PW_EN(x) (0x10118 + (x)*0x100)
33 #define RIO_PLM_SPx_PW_EN_OK2U 0x40000000
34 #define RIO_PLM_SPx_PW_EN_LINIT 0x10000000
36 #define RIO_BC_L2_Gn_ENTRYx_CSR(n, x) (0x31000 + (n)*0x400 + (x)*0x4)
37 #define RIO_SPx_L2_Gn_ENTRYy_CSR(x, n, y) \
38 (0x51000 + (x)*0x2000 + (n)*0x400 + (y)*0x4)
40 static int
41 idtg3_route_add_entry(struct rio_mport *mport, u16 destid, u8 hopcount,
42 u16 table, u16 route_destid, u8 route_port)
44 u32 rval;
45 u32 entry = route_port;
46 int err = 0;
48 pr_debug("RIO: %s t=0x%x did_%x to p_%x\n",
49 __func__, table, route_destid, entry);
51 if (route_destid > 0xFF)
52 return -EINVAL;
54 if (route_port == RIO_INVALID_ROUTE)
55 entry = RIO_RT_ENTRY_DROP_PKT;
57 if (table == RIO_GLOBAL_TABLE) {
58 /* Use broadcast register to update all per-port tables */
59 err = rio_mport_write_config_32(mport, destid, hopcount,
60 RIO_BC_L2_Gn_ENTRYx_CSR(0, route_destid),
61 entry);
62 return err;
66 * Verify that specified port/table number is valid
68 err = rio_mport_read_config_32(mport, destid, hopcount,
69 RIO_SWP_INFO_CAR, &rval);
70 if (err)
71 return err;
73 if (table >= RIO_GET_TOTAL_PORTS(rval))
74 return -EINVAL;
76 err = rio_mport_write_config_32(mport, destid, hopcount,
77 RIO_SPx_L2_Gn_ENTRYy_CSR(table, 0, route_destid),
78 entry);
79 return err;
82 static int
83 idtg3_route_get_entry(struct rio_mport *mport, u16 destid, u8 hopcount,
84 u16 table, u16 route_destid, u8 *route_port)
86 u32 rval;
87 int err;
89 if (route_destid > 0xFF)
90 return -EINVAL;
92 err = rio_mport_read_config_32(mport, destid, hopcount,
93 RIO_SWP_INFO_CAR, &rval);
94 if (err)
95 return err;
98 * This switch device does not have the dedicated global routing table.
99 * It is substituted by reading routing table of the ingress port of
100 * maintenance read requests.
102 if (table == RIO_GLOBAL_TABLE)
103 table = RIO_GET_PORT_NUM(rval);
104 else if (table >= RIO_GET_TOTAL_PORTS(rval))
105 return -EINVAL;
107 err = rio_mport_read_config_32(mport, destid, hopcount,
108 RIO_SPx_L2_Gn_ENTRYy_CSR(table, 0, route_destid),
109 &rval);
110 if (err)
111 return err;
113 if (rval == RIO_RT_ENTRY_DROP_PKT)
114 *route_port = RIO_INVALID_ROUTE;
115 else
116 *route_port = (u8)rval;
118 return 0;
121 static int
122 idtg3_route_clr_table(struct rio_mport *mport, u16 destid, u8 hopcount,
123 u16 table)
125 u32 i;
126 u32 rval;
127 int err;
129 if (table == RIO_GLOBAL_TABLE) {
130 for (i = 0; i <= 0xff; i++) {
131 err = rio_mport_write_config_32(mport, destid, hopcount,
132 RIO_BC_L2_Gn_ENTRYx_CSR(0, i),
133 RIO_RT_ENTRY_DROP_PKT);
134 if (err)
135 break;
138 return err;
141 err = rio_mport_read_config_32(mport, destid, hopcount,
142 RIO_SWP_INFO_CAR, &rval);
143 if (err)
144 return err;
146 if (table >= RIO_GET_TOTAL_PORTS(rval))
147 return -EINVAL;
149 for (i = 0; i <= 0xff; i++) {
150 err = rio_mport_write_config_32(mport, destid, hopcount,
151 RIO_SPx_L2_Gn_ENTRYy_CSR(table, 0, i),
152 RIO_RT_ENTRY_DROP_PKT);
153 if (err)
154 break;
157 return err;
161 * This routine performs device-specific initialization only.
162 * All standard EM configuration should be performed at upper level.
164 static int
165 idtg3_em_init(struct rio_dev *rdev)
167 int i, tmp;
168 u32 rval;
170 pr_debug("RIO: %s [%d:%d]\n", __func__, rdev->destid, rdev->hopcount);
172 /* Disable assertion of interrupt signal */
173 rio_write_config_32(rdev, RIO_EM_DEV_INT_EN, 0);
175 /* Disable port-write event notifications during initialization */
176 rio_write_config_32(rdev, rdev->em_efptr + RIO_EM_PW_TX_CTRL,
177 RIO_EM_PW_TX_CTRL_PW_DIS);
179 /* Configure Port-Write notifications for hot-swap events */
180 tmp = RIO_GET_TOTAL_PORTS(rdev->swpinfo);
181 for (i = 0; i < tmp; i++) {
183 rio_read_config_32(rdev,
184 RIO_DEV_PORT_N_ERR_STS_CSR(rdev, i),
185 &rval);
186 if (rval & RIO_PORT_N_ERR_STS_PORT_UA)
187 continue;
189 /* Clear events signaled before enabling notification */
190 rio_write_config_32(rdev,
191 rdev->em_efptr + RIO_EM_PN_ERR_DETECT(i), 0);
193 /* Enable event notifications */
194 rio_write_config_32(rdev,
195 rdev->em_efptr + RIO_EM_PN_ERRRATE_EN(i),
196 RIO_EM_PN_ERRRATE_EN_OK2U | RIO_EM_PN_ERRRATE_EN_U2OK);
197 /* Enable port-write generation on events */
198 rio_write_config_32(rdev, RIO_PLM_SPx_PW_EN(i),
199 RIO_PLM_SPx_PW_EN_OK2U | RIO_PLM_SPx_PW_EN_LINIT);
203 /* Set Port-Write destination port */
204 tmp = RIO_GET_PORT_NUM(rdev->swpinfo);
205 rio_write_config_32(rdev, RIO_PW_ROUTE, 1 << tmp);
208 /* Enable sending port-write event notifications */
209 rio_write_config_32(rdev, rdev->em_efptr + RIO_EM_PW_TX_CTRL, 0);
211 /* set TVAL = ~50us */
212 rio_write_config_32(rdev,
213 rdev->phys_efptr + RIO_PORT_LINKTO_CTL_CSR, 0x8e << 8);
214 return 0;
219 * idtg3_em_handler - device-specific error handler
221 * If the link is down (PORT_UNINIT) does nothing - this is considered
222 * as link partner removal from the port.
224 * If the link is up (PORT_OK) - situation is handled as *new* device insertion.
225 * In this case ERR_STOP bits are cleared by issuing soft reset command to the
226 * reporting port. Inbound and outbound ackIDs are cleared by the reset as well.
227 * This way the port is synchronized with freshly inserted device (assuming it
228 * was reset/powered-up on insertion).
230 * TODO: This is not sufficient in a situation when a link between two devices
231 * was down and up again (e.g. cable disconnect). For that situation full ackID
232 * realignment process has to be implemented.
234 static int
235 idtg3_em_handler(struct rio_dev *rdev, u8 pnum)
237 u32 err_status;
238 u32 rval;
240 rio_read_config_32(rdev,
241 RIO_DEV_PORT_N_ERR_STS_CSR(rdev, pnum),
242 &err_status);
244 /* Do nothing for device/link removal */
245 if (err_status & RIO_PORT_N_ERR_STS_PORT_UNINIT)
246 return 0;
248 /* When link is OK we have a device insertion.
249 * Request port soft reset to clear errors if they present.
250 * Inbound and outbound ackIDs will be 0 after reset.
252 if (err_status & (RIO_PORT_N_ERR_STS_OUT_ES |
253 RIO_PORT_N_ERR_STS_INP_ES)) {
254 rio_read_config_32(rdev, RIO_PLM_SPx_IMP_SPEC_CTL(pnum), &rval);
255 rio_write_config_32(rdev, RIO_PLM_SPx_IMP_SPEC_CTL(pnum),
256 rval | RIO_PLM_SPx_IMP_SPEC_CTL_SOFT_RST);
257 udelay(10);
258 rio_write_config_32(rdev, RIO_PLM_SPx_IMP_SPEC_CTL(pnum), rval);
259 msleep(500);
262 return 0;
265 static struct rio_switch_ops idtg3_switch_ops = {
266 .owner = THIS_MODULE,
267 .add_entry = idtg3_route_add_entry,
268 .get_entry = idtg3_route_get_entry,
269 .clr_table = idtg3_route_clr_table,
270 .em_init = idtg3_em_init,
271 .em_handle = idtg3_em_handler,
274 static int idtg3_probe(struct rio_dev *rdev, const struct rio_device_id *id)
276 pr_debug("RIO: %s for %s\n", __func__, rio_name(rdev));
278 spin_lock(&rdev->rswitch->lock);
280 if (rdev->rswitch->ops) {
281 spin_unlock(&rdev->rswitch->lock);
282 return -EINVAL;
285 rdev->rswitch->ops = &idtg3_switch_ops;
287 if (rdev->do_enum) {
288 /* Disable hierarchical routing support: Existing fabric
289 * enumeration/discovery process (see rio-scan.c) uses 8-bit
290 * flat destination ID routing only.
292 rio_write_config_32(rdev, 0x5000 + RIO_BC_RT_CTL_CSR, 0);
295 spin_unlock(&rdev->rswitch->lock);
297 return 0;
300 static void idtg3_remove(struct rio_dev *rdev)
302 pr_debug("RIO: %s for %s\n", __func__, rio_name(rdev));
303 spin_lock(&rdev->rswitch->lock);
304 if (rdev->rswitch->ops == &idtg3_switch_ops)
305 rdev->rswitch->ops = NULL;
306 spin_unlock(&rdev->rswitch->lock);
310 * Gen3 switches repeat sending PW messages until a corresponding event flag
311 * is cleared. Use shutdown notification to disable generation of port-write
312 * messages if their destination node is shut down.
314 static void idtg3_shutdown(struct rio_dev *rdev)
316 int i;
317 u32 rval;
318 u16 destid;
320 /* Currently the enumerator node acts also as PW handler */
321 if (!rdev->do_enum)
322 return;
324 pr_debug("RIO: %s(%s)\n", __func__, rio_name(rdev));
326 rio_read_config_32(rdev, RIO_PW_ROUTE, &rval);
327 i = RIO_GET_PORT_NUM(rdev->swpinfo);
329 /* Check port-write destination port */
330 if (!((1 << i) & rval))
331 return;
333 /* Disable sending port-write event notifications if PW destID
334 * matches to one of the enumerator node
336 rio_read_config_32(rdev, rdev->em_efptr + RIO_EM_PW_TGT_DEVID, &rval);
338 if (rval & RIO_EM_PW_TGT_DEVID_DEV16)
339 destid = rval >> 16;
340 else
341 destid = ((rval & RIO_EM_PW_TGT_DEVID_D8) >> 16);
343 if (rdev->net->hport->host_deviceid == destid) {
344 rio_write_config_32(rdev,
345 rdev->em_efptr + RIO_EM_PW_TX_CTRL, 0);
346 pr_debug("RIO: %s(%s) PW transmission disabled\n",
347 __func__, rio_name(rdev));
351 static struct rio_device_id idtg3_id_table[] = {
352 {RIO_DEVICE(RIO_DID_IDTRXS1632, RIO_VID_IDT)},
353 {RIO_DEVICE(RIO_DID_IDTRXS2448, RIO_VID_IDT)},
354 { 0, } /* terminate list */
357 static struct rio_driver idtg3_driver = {
358 .name = "idt_gen3",
359 .id_table = idtg3_id_table,
360 .probe = idtg3_probe,
361 .remove = idtg3_remove,
362 .shutdown = idtg3_shutdown,
365 static int __init idtg3_init(void)
367 return rio_register_driver(&idtg3_driver);
370 static void __exit idtg3_exit(void)
372 pr_debug("RIO: %s\n", __func__);
373 rio_unregister_driver(&idtg3_driver);
374 pr_debug("RIO: %s done\n", __func__);
377 device_initcall(idtg3_init);
378 module_exit(idtg3_exit);
380 MODULE_DESCRIPTION("IDT RXS Gen.3 Serial RapidIO switch family driver");
381 MODULE_AUTHOR("Integrated Device Technology, Inc.");
382 MODULE_LICENSE("GPL");