Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
hp_sdc_mlc.c
Go to the documentation of this file.
1 /*
2  * Access to HP-HIL MLC through HP System Device Controller.
3  *
4  * Copyright (c) 2001 Brian S. Julin
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  * notice, this list of conditions, and the following disclaimer,
12  * without modification.
13  * 2. The name of the author may not be used to endorse or promote products
14  * derived from this software without specific prior written permission.
15  *
16  * Alternatively, this software may be distributed under the terms of the
17  * GNU General Public License ("GPL").
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
23  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  *
29  * References:
30  * HP-HIL Technical Reference Manual. Hewlett Packard Product No. 45918A
31  * System Device Controller Microprocessor Firmware Theory of Operation
32  * for Part Number 1820-4784 Revision B. Dwg No. A-1820-4784-2
33  *
34  */
35 
36 #include <linux/hil_mlc.h>
37 #include <linux/hp_sdc.h>
38 #include <linux/errno.h>
39 #include <linux/kernel.h>
40 #include <linux/module.h>
41 #include <linux/init.h>
42 #include <linux/string.h>
43 #include <linux/semaphore.h>
44 
45 #define PREFIX "HP SDC MLC: "
46 
47 static hil_mlc hp_sdc_mlc;
48 
49 MODULE_AUTHOR("Brian S. Julin <[email protected]>");
50 MODULE_DESCRIPTION("Glue for onboard HIL MLC in HP-PARISC machines");
51 MODULE_LICENSE("Dual BSD/GPL");
52 
53 static struct hp_sdc_mlc_priv_s {
54  int emtestmode;
56  u8 tseq[16];
57  int got5x;
58 } hp_sdc_mlc_priv;
59 
60 /************************* Interrupt context ******************************/
61 static void hp_sdc_mlc_isr (int irq, void *dev_id,
63 {
64  int idx;
65  hil_mlc *mlc = &hp_sdc_mlc;
66 
67  write_lock(&mlc->lock);
68  if (mlc->icount < 0) {
69  printk(KERN_WARNING PREFIX "HIL Overflow!\n");
70  up(&mlc->isem);
71  goto out;
72  }
73  idx = 15 - mlc->icount;
74  if ((status & HP_SDC_STATUS_IRQMASK) == HP_SDC_STATUS_HILDATA) {
75  mlc->ipacket[idx] |= data | HIL_ERR_INT;
76  mlc->icount--;
77  if (hp_sdc_mlc_priv.got5x || !idx)
78  goto check;
79  if ((mlc->ipacket[idx - 1] & HIL_PKT_ADDR_MASK) !=
80  (mlc->ipacket[idx] & HIL_PKT_ADDR_MASK)) {
81  mlc->ipacket[idx] &= ~HIL_PKT_ADDR_MASK;
82  mlc->ipacket[idx] |= (mlc->ipacket[idx - 1]
84  }
85  goto check;
86  }
87  /* We know status is 5X */
88  if (data & HP_SDC_HIL_ISERR)
89  goto err;
90  mlc->ipacket[idx] =
92  hp_sdc_mlc_priv.got5x = 1;
93  goto out;
94 
95  check:
96  hp_sdc_mlc_priv.got5x = 0;
97  if (mlc->imatch == 0)
98  goto done;
99  if ((mlc->imatch == (HIL_ERR_INT | HIL_PKT_CMD | HIL_CMD_POL))
100  && (mlc->ipacket[idx] == (mlc->imatch | idx)))
101  goto done;
102  if (mlc->ipacket[idx] == mlc->imatch)
103  goto done;
104  goto out;
105 
106  err:
107  printk(KERN_DEBUG PREFIX "err code %x\n", data);
108 
109  switch (data) {
110  case HP_SDC_HIL_RC_DONE:
111  printk(KERN_WARNING PREFIX "Bastard SDC reconfigured loop!\n");
112  break;
113 
114  case HP_SDC_HIL_ERR:
115  mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_PERR |
117  break;
118 
119  case HP_SDC_HIL_TO:
120  mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_LERR;
121  break;
122 
123  case HP_SDC_HIL_RC:
124  printk(KERN_WARNING PREFIX "Bastard SDC decided to reconfigure loop!\n");
125  break;
126 
127  default:
128  printk(KERN_WARNING PREFIX "Unknown HIL Error status (%x)!\n", data);
129  break;
130  }
131 
132  /* No more data will be coming due to an error. */
133  done:
134  tasklet_schedule(mlc->tasklet);
135  up(&mlc->isem);
136  out:
137  write_unlock(&mlc->lock);
138 }
139 
140 
141 /******************** Tasklet or userspace context functions ****************/
142 
143 static int hp_sdc_mlc_in(hil_mlc *mlc, suseconds_t timeout)
144 {
145  struct hp_sdc_mlc_priv_s *priv;
146  int rc = 2;
147 
148  priv = mlc->priv;
149 
150  /* Try to down the semaphore */
151  if (down_trylock(&mlc->isem)) {
152  struct timeval tv;
153  if (priv->emtestmode) {
154  mlc->ipacket[0] =
155  HIL_ERR_INT | (mlc->opacket &
156  (HIL_PKT_CMD |
159  mlc->icount = 14;
160  /* printk(KERN_DEBUG PREFIX ">[%x]\n", mlc->ipacket[0]); */
161  goto wasup;
162  }
163  do_gettimeofday(&tv);
164  tv.tv_usec += USEC_PER_SEC * (tv.tv_sec - mlc->instart.tv_sec);
165  if (tv.tv_usec - mlc->instart.tv_usec > mlc->intimeout) {
166  /* printk("!%i %i",
167  tv.tv_usec - mlc->instart.tv_usec,
168  mlc->intimeout);
169  */
170  rc = 1;
171  up(&mlc->isem);
172  }
173  goto done;
174  }
175  wasup:
176  up(&mlc->isem);
177  rc = 0;
178  done:
179  return rc;
180 }
181 
182 static int hp_sdc_mlc_cts(hil_mlc *mlc)
183 {
184  struct hp_sdc_mlc_priv_s *priv;
185 
186  priv = mlc->priv;
187 
188  /* Try to down the semaphores -- they should be up. */
189  BUG_ON(down_trylock(&mlc->isem));
190  BUG_ON(down_trylock(&mlc->osem));
191 
192  up(&mlc->isem);
193  up(&mlc->osem);
194 
195  if (down_trylock(&mlc->csem)) {
196  if (priv->trans.act.semaphore != &mlc->csem)
197  goto poll;
198  else
199  goto busy;
200  }
201 
202  if (!(priv->tseq[4] & HP_SDC_USE_LOOP))
203  goto done;
204 
205  poll:
206  priv->trans.act.semaphore = &mlc->csem;
207  priv->trans.actidx = 0;
208  priv->trans.idx = 1;
209  priv->trans.endidx = 5;
210  priv->tseq[0] =
212  priv->tseq[1] = HP_SDC_CMD_READ_USE;
213  priv->tseq[2] = 1;
214  priv->tseq[3] = 0;
215  priv->tseq[4] = 0;
216  __hp_sdc_enqueue_transaction(&priv->trans);
217  busy:
218  return 1;
219  done:
220  priv->trans.act.semaphore = &mlc->osem;
221  up(&mlc->csem);
222  return 0;
223 }
224 
225 static void hp_sdc_mlc_out(hil_mlc *mlc)
226 {
227  struct hp_sdc_mlc_priv_s *priv;
228 
229  priv = mlc->priv;
230 
231  /* Try to down the semaphore -- it should be up. */
232  BUG_ON(down_trylock(&mlc->osem));
233 
234  if (mlc->opacket & HIL_DO_ALTER_CTRL)
235  goto do_control;
236 
237  do_data:
238  if (priv->emtestmode) {
239  up(&mlc->osem);
240  return;
241  }
242  /* Shouldn't be sending commands when loop may be busy */
243  BUG_ON(down_trylock(&mlc->csem));
244  up(&mlc->csem);
245 
246  priv->trans.actidx = 0;
247  priv->trans.idx = 1;
248  priv->trans.act.semaphore = &mlc->osem;
249  priv->trans.endidx = 6;
250  priv->tseq[0] =
252  priv->tseq[1] = 0x7;
253  priv->tseq[2] =
254  (mlc->opacket &
257  priv->tseq[3] =
258  (mlc->opacket & HIL_PKT_DATA_MASK)
260  priv->tseq[4] = 0; /* No timeout */
261  if (priv->tseq[3] == HIL_CMD_DHR)
262  priv->tseq[4] = 1;
263  priv->tseq[5] = HP_SDC_CMD_DO_HIL;
264  goto enqueue;
265 
266  do_control:
267  priv->emtestmode = mlc->opacket & HIL_CTRL_TEST;
268 
269  /* we cannot emulate this, it should not be used. */
271 
272  if ((mlc->opacket & HIL_CTRL_ONLY) == HIL_CTRL_ONLY)
273  goto control_only;
274 
275  /* Should not send command/data after engaging APE */
276  BUG_ON(mlc->opacket & HIL_CTRL_APE);
277 
278  /* Disengaging APE this way would not be valid either since
279  * the loop must be allowed to idle.
280  *
281  * So, it works out that we really never actually send control
282  * and data when using SDC, we just send the data.
283  */
284  goto do_data;
285 
286  control_only:
287  priv->trans.actidx = 0;
288  priv->trans.idx = 1;
289  priv->trans.act.semaphore = &mlc->osem;
290  priv->trans.endidx = 4;
291  priv->tseq[0] =
293  priv->tseq[1] = HP_SDC_CMD_SET_LPC;
294  priv->tseq[2] = 1;
295  /* priv->tseq[3] = (mlc->ddc + 1) | HP_SDC_LPS_ACSUCC; */
296  priv->tseq[3] = 0;
297  if (mlc->opacket & HIL_CTRL_APE) {
298  priv->tseq[3] |= HP_SDC_LPC_APE_IPF;
299  BUG_ON(down_trylock(&mlc->csem));
300  }
301  enqueue:
302  hp_sdc_enqueue_transaction(&priv->trans);
303 }
304 
305 static int __init hp_sdc_mlc_init(void)
306 {
307  hil_mlc *mlc = &hp_sdc_mlc;
308  int err;
309 
310 #ifdef __mc68000__
311  if (!MACH_IS_HP300)
312  return -ENODEV;
313 #endif
314 
315  printk(KERN_INFO PREFIX "Registering the System Domain Controller's HIL MLC.\n");
316 
317  hp_sdc_mlc_priv.emtestmode = 0;
318  hp_sdc_mlc_priv.trans.seq = hp_sdc_mlc_priv.tseq;
319  hp_sdc_mlc_priv.trans.act.semaphore = &mlc->osem;
320  hp_sdc_mlc_priv.got5x = 0;
321 
322  mlc->cts = &hp_sdc_mlc_cts;
323  mlc->in = &hp_sdc_mlc_in;
324  mlc->out = &hp_sdc_mlc_out;
325  mlc->priv = &hp_sdc_mlc_priv;
326 
327  err = hil_mlc_register(mlc);
328  if (err) {
329  printk(KERN_WARNING PREFIX "Failed to register MLC structure with hil_mlc\n");
330  return err;
331  }
332 
333  if (hp_sdc_request_hil_irq(&hp_sdc_mlc_isr)) {
334  printk(KERN_WARNING PREFIX "Request for raw HIL ISR hook denied\n");
335  if (hil_mlc_unregister(mlc))
336  printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
337  "This is bad. Could cause an oops.\n");
338  return -EBUSY;
339  }
340 
341  return 0;
342 }
343 
344 static void __exit hp_sdc_mlc_exit(void)
345 {
346  hil_mlc *mlc = &hp_sdc_mlc;
347 
348  if (hp_sdc_release_hil_irq(&hp_sdc_mlc_isr))
349  printk(KERN_ERR PREFIX "Failed to release the raw HIL ISR hook.\n"
350  "This is bad. Could cause an oops.\n");
351 
352  if (hil_mlc_unregister(mlc))
353  printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
354  "This is bad. Could cause an oops.\n");
355 }
356 
357 module_init(hp_sdc_mlc_init);
358 module_exit(hp_sdc_mlc_exit);