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 <bri@calyx.com>"); 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; 55 hp_sdc_transaction trans; 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, 62 uint8_t status, uint8_t data) 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] 83 & HIL_PKT_ADDR_MASK); 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] = 91 (data & HP_SDC_HIL_R1MASK) << HIL_PKT_ADDR_SHIFT; 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 | 116 HIL_ERR_FERR | HIL_ERR_FOF; 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 if (priv->emtestmode) { 153 mlc->ipacket[0] = 154 HIL_ERR_INT | (mlc->opacket & 155 (HIL_PKT_CMD | 156 HIL_PKT_ADDR_MASK | 157 HIL_PKT_DATA_MASK)); 158 mlc->icount = 14; 159 /* printk(KERN_DEBUG PREFIX ">[%x]\n", mlc->ipacket[0]); */ 160 goto wasup; 161 } 162 if (time_after(jiffies, mlc->instart + mlc->intimeout)) { 163 /* printk("!%i %i", 164 tv.tv_usec - mlc->instart.tv_usec, 165 mlc->intimeout); 166 */ 167 rc = 1; 168 up(&mlc->isem); 169 } 170 goto done; 171 } 172 wasup: 173 up(&mlc->isem); 174 rc = 0; 175 done: 176 return rc; 177 } 178 179 static int hp_sdc_mlc_cts(hil_mlc *mlc) 180 { 181 struct hp_sdc_mlc_priv_s *priv; 182 183 priv = mlc->priv; 184 185 /* Try to down the semaphores -- they should be up. */ 186 BUG_ON(down_trylock(&mlc->isem)); 187 BUG_ON(down_trylock(&mlc->osem)); 188 189 up(&mlc->isem); 190 up(&mlc->osem); 191 192 if (down_trylock(&mlc->csem)) { 193 if (priv->trans.act.semaphore != &mlc->csem) 194 goto poll; 195 else 196 goto busy; 197 } 198 199 if (!(priv->tseq[4] & HP_SDC_USE_LOOP)) 200 goto done; 201 202 poll: 203 priv->trans.act.semaphore = &mlc->csem; 204 priv->trans.actidx = 0; 205 priv->trans.idx = 1; 206 priv->trans.endidx = 5; 207 priv->tseq[0] = 208 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN | HP_SDC_ACT_SEMAPHORE; 209 priv->tseq[1] = HP_SDC_CMD_READ_USE; 210 priv->tseq[2] = 1; 211 priv->tseq[3] = 0; 212 priv->tseq[4] = 0; 213 __hp_sdc_enqueue_transaction(&priv->trans); 214 busy: 215 return 1; 216 done: 217 priv->trans.act.semaphore = &mlc->osem; 218 up(&mlc->csem); 219 return 0; 220 } 221 222 static void hp_sdc_mlc_out(hil_mlc *mlc) 223 { 224 struct hp_sdc_mlc_priv_s *priv; 225 226 priv = mlc->priv; 227 228 /* Try to down the semaphore -- it should be up. */ 229 BUG_ON(down_trylock(&mlc->osem)); 230 231 if (mlc->opacket & HIL_DO_ALTER_CTRL) 232 goto do_control; 233 234 do_data: 235 if (priv->emtestmode) { 236 up(&mlc->osem); 237 return; 238 } 239 /* Shouldn't be sending commands when loop may be busy */ 240 BUG_ON(down_trylock(&mlc->csem)); 241 up(&mlc->csem); 242 243 priv->trans.actidx = 0; 244 priv->trans.idx = 1; 245 priv->trans.act.semaphore = &mlc->osem; 246 priv->trans.endidx = 6; 247 priv->tseq[0] = 248 HP_SDC_ACT_DATAREG | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_SEMAPHORE; 249 priv->tseq[1] = 0x7; 250 priv->tseq[2] = 251 (mlc->opacket & 252 (HIL_PKT_ADDR_MASK | HIL_PKT_CMD)) 253 >> HIL_PKT_ADDR_SHIFT; 254 priv->tseq[3] = 255 (mlc->opacket & HIL_PKT_DATA_MASK) 256 >> HIL_PKT_DATA_SHIFT; 257 priv->tseq[4] = 0; /* No timeout */ 258 if (priv->tseq[3] == HIL_CMD_DHR) 259 priv->tseq[4] = 1; 260 priv->tseq[5] = HP_SDC_CMD_DO_HIL; 261 goto enqueue; 262 263 do_control: 264 priv->emtestmode = mlc->opacket & HIL_CTRL_TEST; 265 266 /* we cannot emulate this, it should not be used. */ 267 BUG_ON((mlc->opacket & (HIL_CTRL_APE | HIL_CTRL_IPF)) == HIL_CTRL_APE); 268 269 if ((mlc->opacket & HIL_CTRL_ONLY) == HIL_CTRL_ONLY) 270 goto control_only; 271 272 /* Should not send command/data after engaging APE */ 273 BUG_ON(mlc->opacket & HIL_CTRL_APE); 274 275 /* Disengaging APE this way would not be valid either since 276 * the loop must be allowed to idle. 277 * 278 * So, it works out that we really never actually send control 279 * and data when using SDC, we just send the data. 280 */ 281 goto do_data; 282 283 control_only: 284 priv->trans.actidx = 0; 285 priv->trans.idx = 1; 286 priv->trans.act.semaphore = &mlc->osem; 287 priv->trans.endidx = 4; 288 priv->tseq[0] = 289 HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT | HP_SDC_ACT_SEMAPHORE; 290 priv->tseq[1] = HP_SDC_CMD_SET_LPC; 291 priv->tseq[2] = 1; 292 /* priv->tseq[3] = (mlc->ddc + 1) | HP_SDC_LPS_ACSUCC; */ 293 priv->tseq[3] = 0; 294 if (mlc->opacket & HIL_CTRL_APE) { 295 priv->tseq[3] |= HP_SDC_LPC_APE_IPF; 296 BUG_ON(down_trylock(&mlc->csem)); 297 } 298 enqueue: 299 hp_sdc_enqueue_transaction(&priv->trans); 300 } 301 302 static int __init hp_sdc_mlc_init(void) 303 { 304 hil_mlc *mlc = &hp_sdc_mlc; 305 int err; 306 307 #ifdef __mc68000__ 308 if (!MACH_IS_HP300) 309 return -ENODEV; 310 #endif 311 312 printk(KERN_INFO PREFIX "Registering the System Domain Controller's HIL MLC.\n"); 313 314 hp_sdc_mlc_priv.emtestmode = 0; 315 hp_sdc_mlc_priv.trans.seq = hp_sdc_mlc_priv.tseq; 316 hp_sdc_mlc_priv.trans.act.semaphore = &mlc->osem; 317 hp_sdc_mlc_priv.got5x = 0; 318 319 mlc->cts = &hp_sdc_mlc_cts; 320 mlc->in = &hp_sdc_mlc_in; 321 mlc->out = &hp_sdc_mlc_out; 322 mlc->priv = &hp_sdc_mlc_priv; 323 324 err = hil_mlc_register(mlc); 325 if (err) { 326 printk(KERN_WARNING PREFIX "Failed to register MLC structure with hil_mlc\n"); 327 return err; 328 } 329 330 if (hp_sdc_request_hil_irq(&hp_sdc_mlc_isr)) { 331 printk(KERN_WARNING PREFIX "Request for raw HIL ISR hook denied\n"); 332 if (hil_mlc_unregister(mlc)) 333 printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n" 334 "This is bad. Could cause an oops.\n"); 335 return -EBUSY; 336 } 337 338 return 0; 339 } 340 341 static void __exit hp_sdc_mlc_exit(void) 342 { 343 hil_mlc *mlc = &hp_sdc_mlc; 344 345 if (hp_sdc_release_hil_irq(&hp_sdc_mlc_isr)) 346 printk(KERN_ERR PREFIX "Failed to release the raw HIL ISR hook.\n" 347 "This is bad. Could cause an oops.\n"); 348 349 if (hil_mlc_unregister(mlc)) 350 printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n" 351 "This is bad. Could cause an oops.\n"); 352 } 353 354 module_init(hp_sdc_mlc_init); 355 module_exit(hp_sdc_mlc_exit); 356