xref: /netbsd-src/sys/arch/arm/xscale/ixp425_npe.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /*	$NetBSD: ixp425_npe.c,v 1.8 2011/07/01 20:32:51 dyoung Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006 Sam Leffler, Errno Consulting
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. Redistributions in binary form must reproduce at minimum a disclaimer
14  *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
15  *    redistribution must be conditioned upon including a substantially
16  *    similar Disclaimer requirement for further binary redistribution.
17  *
18  * NO WARRANTY
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
22  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23  * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
24  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
27  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29  * THE POSSIBILITY OF SUCH DAMAGES.
30  */
31 
32 /*-
33  * Copyright (c) 2001-2005, Intel Corporation.
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the Intel Corporation nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
50  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60 */
61 #include <sys/cdefs.h>
62 #if 0
63 __FBSDID("$FreeBSD: src/sys/arm/xscale/ixp425/ixp425_npe.c,v 1.1 2006/11/19 23:55:23 sam Exp $");
64 #endif
65 __KERNEL_RCSID(0, "$NetBSD: ixp425_npe.c,v 1.8 2011/07/01 20:32:51 dyoung Exp $");
66 
67 /*
68  * Intel XScale Network Processing Engine (NPE) support.
69  *
70  * Each NPE has an ixpnpeX device associated with it that is
71  * attached at boot.  Depending on the microcode loaded into
72  * an NPE there may be an Ethernet interface (npeX) or some
73  * other network interface (e.g. for ATM).  This file has support
74  * for loading microcode images and the associated NPE CPU
75  * manipulations (start, stop, reset).
76  *
77  * The code here basically replaces the npeDl and npeMh classes
78  * in the Intel Access Library (IAL).
79  *
80  * NB: Microcode images are loaded with firmware(9).  To
81  *     include microcode in a static kernel include the
82  *     ixpnpe_fw device.  Otherwise the firmware will be
83  *     automatically loaded from the filesystem.
84  */
85 #include <sys/param.h>
86 #include <sys/systm.h>
87 #include <sys/kernel.h>
88 #include <sys/malloc.h>
89 #include <sys/simplelock.h>
90 #include <sys/time.h>
91 #include <sys/proc.h>
92 
93 #include <dev/firmload.h>
94 
95 #include <sys/bus.h>
96 #include <machine/cpu.h>
97 #include <machine/intr.h>
98 
99 #include <arm/xscale/ixp425reg.h>
100 #include <arm/xscale/ixp425var.h>
101 #include <arm/xscale/ixp425_ixmevar.h>
102 
103 #include <arm/xscale/ixp425_npereg.h>
104 #include <arm/xscale/ixp425_npevar.h>
105 #include <arm/xscale/ixp425_if_npereg.h>
106 
107 #include "locators.h"
108 
109 /*
110  * IXP425_NPE_MICROCODE will be defined by ixp425-fw.mk IFF the
111  * microcode object file exists in sys/arch/arm/xscale.
112  *
113  * To permit building the NPE drivers without microcode (so they
114  * don't bitrot due to lack of use), we use "empty" microcode so
115  * that the NPE drivers will simply fail to start at runtime.
116  */
117 #ifdef IXP425_NPE_MICROCODE
118 extern char	_binary_IxNpeMicrocode_dat_start[];
119 #else
120 static char	_binary_IxNpeMicrocode_dat_start[] = {
121 	0xfe, 0xed, 0xf0, 0x0d, 0xfe, 0xed, 0xf0, 0x0d
122 };
123 #endif
124 
125 #define	IX_NPEDL_NPEIMAGE_FIELD_MASK	0xff
126 
127 /* used to read download map from version in microcode image */
128 #define IX_NPEDL_BLOCK_TYPE_INSTRUCTION	0x00000000
129 #define IX_NPEDL_BLOCK_TYPE_DATA	0x00000001
130 #define IX_NPEDL_BLOCK_TYPE_STATE	0x00000002
131 #define IX_NPEDL_END_OF_DOWNLOAD_MAP	0x0000000F
132 
133 /*
134  * masks used to extract address info from State information context
135  * register addresses as read from microcode image
136  */
137 #define IX_NPEDL_MASK_STATE_ADDR_CTXT_REG         0x0000000F
138 #define IX_NPEDL_MASK_STATE_ADDR_CTXT_NUM         0x000000F0
139 
140 /* LSB offset of Context Number field in State-Info Context Address */
141 #define IX_NPEDL_OFFSET_STATE_ADDR_CTXT_NUM       4
142 
143 /* size (in words) of single State Information entry (ctxt reg address|data) */
144 #define IX_NPEDL_STATE_INFO_ENTRY_SIZE	2
145 
146 typedef struct {
147     uint32_t type;
148     uint32_t offset;
149 } IxNpeDlNpeMgrDownloadMapBlockEntry;
150 
151 typedef union {
152     IxNpeDlNpeMgrDownloadMapBlockEntry block;
153     uint32_t eodmMarker;
154 } IxNpeDlNpeMgrDownloadMapEntry;
155 
156 typedef struct {
157     /* 1st entry in the download map (there may be more than one) */
158     IxNpeDlNpeMgrDownloadMapEntry entry[1];
159 } IxNpeDlNpeMgrDownloadMap;
160 
161 /* used to access an instruction or data block in a microcode image */
162 typedef struct {
163     uint32_t npeMemAddress;
164     uint32_t size;
165     uint32_t data[1];
166 } IxNpeDlNpeMgrCodeBlock;
167 
168 /* used to access each Context Reg entry state-information block */
169 typedef struct {
170     uint32_t addressInfo;
171     uint32_t value;
172 } IxNpeDlNpeMgrStateInfoCtxtRegEntry;
173 
174 /* used to access a state-information block in a microcode image */
175 typedef struct {
176     uint32_t size;
177     IxNpeDlNpeMgrStateInfoCtxtRegEntry ctxtRegEntry[1];
178 } IxNpeDlNpeMgrStateInfoBlock;
179 
180 static int npe_debug = 0;
181 #define	DPRINTF(dev, fmt, ...) do {				\
182 	if (npe_debug) printf(fmt, __VA_ARGS__);		\
183 } while (0)
184 #define	DPRINTFn(n, dev, fmt, ...) do {				\
185 	if (npe_debug >= n) printf(fmt, __VA_ARGS__);		\
186 } while (0)
187 
188 static int npe_checkbits(struct ixpnpe_softc *, uint32_t reg, uint32_t);
189 static int npe_isstopped(struct ixpnpe_softc *);
190 static int npe_load_ins(struct ixpnpe_softc *,
191 		const IxNpeDlNpeMgrCodeBlock *bp, int verify);
192 static int npe_load_data(struct ixpnpe_softc *,
193 		const IxNpeDlNpeMgrCodeBlock *bp, int verify);
194 static int npe_load_stateinfo(struct ixpnpe_softc *,
195 		const IxNpeDlNpeMgrStateInfoBlock *bp, int verify);
196 static int npe_load_image(struct ixpnpe_softc *,
197 		const uint32_t *imageCodePtr, int verify);
198 static int npe_cpu_reset(struct ixpnpe_softc *);
199 static int npe_cpu_start(struct ixpnpe_softc *);
200 static int npe_cpu_stop(struct ixpnpe_softc *);
201 static void npe_cmd_issue_write(struct ixpnpe_softc *,
202 		uint32_t cmd, uint32_t addr, uint32_t data);
203 static uint32_t npe_cmd_issue_read(struct ixpnpe_softc *,
204 		uint32_t cmd, uint32_t addr);
205 static int npe_ins_write(struct ixpnpe_softc *,
206 		uint32_t addr, uint32_t data, int verify);
207 static int npe_data_write(struct ixpnpe_softc *,
208 		uint32_t addr, uint32_t data, int verify);
209 static void npe_ecs_reg_write(struct ixpnpe_softc *,
210 		uint32_t reg, uint32_t data);
211 static uint32_t npe_ecs_reg_read(struct ixpnpe_softc *, uint32_t reg);
212 static void npe_issue_cmd(struct ixpnpe_softc *, uint32_t command);
213 static void npe_cpu_step_save(struct ixpnpe_softc *);
214 static int npe_cpu_step(struct ixpnpe_softc *, uint32_t npeInstruction,
215 		uint32_t ctxtNum, uint32_t ldur);
216 static void npe_cpu_step_restore(struct ixpnpe_softc *);
217 static int npe_logical_reg_read(struct ixpnpe_softc *,
218 		uint32_t regAddr, uint32_t regSize,
219 		uint32_t ctxtNum, uint32_t *regVal);
220 static int npe_logical_reg_write(struct ixpnpe_softc *,
221 		uint32_t regAddr, uint32_t regVal,
222 		uint32_t regSize, uint32_t ctxtNum, int verify);
223 static int npe_physical_reg_write(struct ixpnpe_softc *,
224 		uint32_t regAddr, uint32_t regValue, int verify);
225 static int npe_ctx_reg_write(struct ixpnpe_softc *, uint32_t ctxtNum,
226 		uint32_t ctxtReg, uint32_t ctxtRegVal, int verify);
227 
228 static int ixpnpe_intr(void *arg);
229 
230 static uint32_t
231 npe_reg_read(struct ixpnpe_softc *sc, bus_size_t off)
232 {
233     uint32_t v = bus_space_read_4(sc->sc_iot, sc->sc_ioh, off);
234     DPRINTFn(9, sc->sc_dev, "%s(0x%lx) => 0x%x\n", __func__, off, v);
235     return v;
236 }
237 
238 static void
239 npe_reg_write(struct ixpnpe_softc *sc, bus_size_t off, uint32_t val)
240 {
241     DPRINTFn(9, sc->sc_dev, "%s(0x%lx, 0x%x)\n", __func__, off, val);
242     bus_space_write_4(sc->sc_iot, sc->sc_ioh, off, val);
243 }
244 
245 static int	ixpnpe_match(struct device *, struct cfdata *, void *);
246 static void	ixpnpe_attach(struct device *, struct device *, void *);
247 static int	ixpnpe_print(void *, const char *);
248 static int	ixpnpe_search(struct device *, struct cfdata *, const int *,
249 		    void *);
250 
251 CFATTACH_DECL(ixpnpe, sizeof(struct ixpnpe_softc),
252     ixpnpe_match, ixpnpe_attach, NULL, NULL);
253 
254 static int
255 ixpnpe_match(struct device *parent, struct cfdata *match, void *arg)
256 {
257 	struct ixme_attach_args *ixa = arg;
258 
259 	return (ixa->ixa_npe == 1 || ixa->ixa_npe == 2);
260 }
261 
262 static void
263 ixpnpe_attach(struct device *parent, struct device *self, void *arg)
264 {
265     struct ixpnpe_softc *sc = (void *)self;
266     struct ixme_attach_args *ixa = arg;
267     bus_addr_t base;
268     int irq;
269 
270     aprint_naive("\n");
271     aprint_normal("\n");
272 
273     sc->sc_iot = ixa->ixa_iot;
274     sc->sc_dt = ixa->ixa_dt;
275     sc->sc_unit = ixa->ixa_npe;
276 
277     simple_lock_init(&sc->sc_lock);
278 
279     /* XXX: Check features to ensure this NPE is enabled */
280 
281     switch (ixa->ixa_npe) {
282     default:
283 	panic("%s: Invalid NPE!", sc->sc_dev.dv_xname);
284 
285     case 1:
286 	base = IXP425_NPE_B_HWBASE;
287 	sc->sc_size = IXP425_NPE_B_SIZE;
288 	irq = IXP425_INT_NPE_B;
289 
290 	/* size of instruction memory */
291 	sc->insMemSize = IX_NPEDL_INS_MEMSIZE_WORDS_NPEB;
292 	/* size of data memory */
293 	sc->dataMemSize = IX_NPEDL_DATA_MEMSIZE_WORDS_NPEB;
294 	break;
295 
296     case 2:
297 	base = IXP425_NPE_C_HWBASE;
298 	sc->sc_size = IXP425_NPE_C_SIZE;
299 	irq = IXP425_INT_NPE_C;
300 
301 	/* size of instruction memory */
302 	sc->insMemSize = IX_NPEDL_INS_MEMSIZE_WORDS_NPEC;
303 	/* size of data memory */
304 	sc->dataMemSize = IX_NPEDL_DATA_MEMSIZE_WORDS_NPEC;
305 	break;
306     }
307     if (bus_space_map(sc->sc_iot, base, sc->sc_size, 0, &sc->sc_ioh))
308 	panic("%s: Cannot map registers", sc->sc_dev.dv_xname);
309 
310     /*
311      * Setup IRQ and handler for NPE message support.
312      */
313     sc->sc_ih = ixp425_intr_establish(irq, IPL_NET, ixpnpe_intr, sc);
314     if (sc->sc_ih == NULL)
315 	panic("%s: Unable to establish irq %u", sc->sc_dev.dv_xname, irq);
316     /* enable output fifo interrupts (NB: must also set OFIFO Write Enable) */
317     npe_reg_write(sc, IX_NPECTL,
318 	npe_reg_read(sc, IX_NPECTL) | (IX_NPECTL_OFE | IX_NPECTL_OFWE));
319 
320     config_search_ia(ixpnpe_search, self, "ixpnpe", ixa);
321 }
322 
323 static int
324 ixpnpe_print(void *arg, const char *name)
325 {
326 
327 	return (UNCONF);
328 }
329 
330 static int
331 ixpnpe_search(struct device *parent, struct cfdata *cf, const int *ldesc,
332     void *arg)
333 {
334 	struct ixpnpe_softc *sc = (void *)parent;
335 	struct ixme_attach_args *ixa = arg;
336 	struct ixpnpe_attach_args na;
337 
338 	na.na_unit = ixa->ixa_npe;
339 	na.na_phy = cf->cf_loc[IXPNPECF_PHY];
340 	na.na_npe = sc;
341 	na.na_iot = ixa->ixa_iot;
342 	na.na_dt = ixa->ixa_dt;
343 
344 	if (config_match(parent, cf, &na) > 0) {
345 		config_attach(parent, cf, &na, ixpnpe_print);
346 		return (1);
347 	}
348 
349 	return (0);
350 }
351 
352 int
353 ixpnpe_stopandreset(struct ixpnpe_softc *sc)
354 {
355     int error;
356 
357     simple_lock(&sc->sc_lock);
358     error = npe_cpu_stop(sc);		/* stop NPE */
359     if (error == 0)
360 	error = npe_cpu_reset(sc);	/* reset it */
361     if (error == 0)
362 	sc->started = 0;		/* mark stopped */
363     simple_unlock(&sc->sc_lock);
364 
365     DPRINTF(sc->sc_dev, "%s: error %d\n", __func__, error);
366     return error;
367 }
368 
369 static int
370 ixpnpe_start_locked(struct ixpnpe_softc *sc)
371 {
372     int error;
373 
374     if (!sc->started) {
375 	error = npe_cpu_start(sc);
376 	if (error == 0)
377 	    sc->started = 1;
378     } else
379 	error = 0;
380 
381     DPRINTF(sc->sc_dev, "%s: error %d\n", __func__, error);
382     return error;
383 }
384 
385 int
386 ixpnpe_start(struct ixpnpe_softc *sc)
387 {
388 	int ret;
389 
390 	simple_lock(&sc->sc_lock);
391 	ret = ixpnpe_start_locked(sc);
392 	simple_unlock(&sc->sc_lock);
393 	return (ret);
394 }
395 
396 int
397 ixpnpe_stop(struct ixpnpe_softc *sc)
398 {
399     int error;
400 
401     simple_lock(&sc->sc_lock);
402     error = npe_cpu_stop(sc);
403     if (error == 0)
404 	sc->started = 0;
405     simple_unlock(&sc->sc_lock);
406 
407     DPRINTF(sc->sc_dev, "%s: error %d\n", __func__, error);
408     return error;
409 }
410 
411 /*
412  * Indicates the start of an NPE Image, in new NPE Image Library format.
413  * 2 consecutive occurances indicates the end of the NPE Image Library
414  */
415 #define NPE_IMAGE_MARKER 0xfeedf00d
416 
417 /*
418  * NPE Image Header definition, used in new NPE Image Library format
419  */
420 typedef struct {
421     uint32_t marker;
422     uint32_t id;
423     uint32_t size;
424 } IxNpeDlImageMgrImageHeader;
425 
426 static int
427 npe_findimage(struct ixpnpe_softc *sc,
428     const uint32_t *imageLibrary, uint32_t imageId,
429     const uint32_t **imagePtr, uint32_t *imageSize)
430 {
431     const IxNpeDlImageMgrImageHeader *image;
432     uint32_t offset = 0;
433 
434     while (imageLibrary[offset] == NPE_IMAGE_MARKER) {
435         image = (const IxNpeDlImageMgrImageHeader *)&imageLibrary[offset];
436         offset += sizeof(IxNpeDlImageMgrImageHeader)/sizeof(uint32_t);
437 
438         DPRINTF(sc->sc_dev, "%s: off %u mark 0x%x id 0x%x size %u\n",
439 	    __func__, offset, image->marker, image->id, image->size);
440         if (image->id == imageId) {
441             *imagePtr = imageLibrary + offset;
442             *imageSize = image->size;
443             return 0;
444         }
445         /* 2 consecutive NPE_IMAGE_MARKER's indicates end of library */
446         if (image->id == NPE_IMAGE_MARKER) {
447 	    printf("%s: imageId 0x%08x not found in image library header\n",
448 	        sc->sc_dev.dv_xname, imageId);
449             /* reached end of library, image not found */
450             return EIO;
451         }
452         offset += image->size;
453     }
454     return EIO;
455 }
456 
457 int
458 ixpnpe_init(struct ixpnpe_softc *sc, const char *imageName, uint32_t imageId)
459 {
460     uint32_t imageSize;
461     const uint32_t *imageCodePtr;
462     void *fw;
463     int error;
464 
465     DPRINTF(sc->sc_dev, "load %s, imageId 0x%08x\n", imageName, imageId);
466 
467 #if 0
468     IxFeatureCtrlDeviceId devid = IX_NPEDL_DEVICEID_FROM_IMAGEID_GET(imageId);
469     /*
470      * Checking if image being loaded is meant for device that is running.
471      * Image is forward compatible. i.e Image built for IXP42X should run
472      * on IXP46X but not vice versa.
473      */
474     if (devid > (ixFeatureCtrlDeviceRead() & IX_FEATURE_CTRL_DEVICE_TYPE_MASK))
475 	return EINVAL;
476 #endif
477     error = ixpnpe_stopandreset(sc);		/* stop and reset the NPE */
478     if (error != 0)
479 	return error;
480 
481     fw = (void *)_binary_IxNpeMicrocode_dat_start;
482 
483     /* Locate desired image in files w/ combined images */
484     error = npe_findimage(sc, (void *)fw /*fw->data*/, imageId, &imageCodePtr, &imageSize);
485     if (error != 0)
486 	goto done;
487 
488     /*
489      * If download was successful, store image Id in list of
490      * currently loaded images. If a critical error occured
491      * during download, record that the NPE has an invalid image
492      */
493     simple_lock(&sc->sc_lock);
494     error = npe_load_image(sc, imageCodePtr, 1 /*VERIFY*/);
495     if (error == 0) {
496 	sc->validImage = 1;
497 	error = ixpnpe_start_locked(sc);
498     } else {
499 	sc->validImage = 0;
500     }
501     sc->functionalityId = IX_NPEDL_FUNCTIONID_FROM_IMAGEID_GET(imageId);
502     simple_unlock(&sc->sc_lock);
503 done:
504     DPRINTF(sc->sc_dev, "%s: error %d\n", __func__, error);
505     return error;
506 }
507 
508 int
509 ixpnpe_getfunctionality(struct ixpnpe_softc *sc)
510 {
511     return (sc->validImage ? sc->functionalityId : 0);
512 }
513 
514 static int
515 npe_checkbits(struct ixpnpe_softc *sc, uint32_t reg, uint32_t expectedBitsSet)
516 {
517     uint32_t val;
518 
519     val = npe_reg_read(sc, reg);
520     DPRINTFn(5, sc->sc_dev, "%s(0x%x, 0x%x) => 0x%x (%u)\n",
521 	__func__, reg, expectedBitsSet, val,
522 	(val & expectedBitsSet) == expectedBitsSet);
523     return ((val & expectedBitsSet) == expectedBitsSet);
524 }
525 
526 static int
527 npe_isstopped(struct ixpnpe_softc *sc)
528 {
529     return npe_checkbits(sc,
530 	IX_NPEDL_REG_OFFSET_EXCTL, IX_NPEDL_EXCTL_STATUS_STOP);
531 }
532 
533 static int
534 npe_load_ins(struct ixpnpe_softc *sc,
535     const IxNpeDlNpeMgrCodeBlock *bp, int verify)
536 {
537     uint32_t npeMemAddress;
538     int i, blockSize;
539 
540     npeMemAddress = bp->npeMemAddress;
541     blockSize = bp->size;		/* NB: instruction/data count */
542     if (npeMemAddress + blockSize > sc->insMemSize) {
543 	printf("%s: Block size too big for NPE memory\n", sc->sc_dev.dv_xname);
544 	return EINVAL;	/* XXX */
545     }
546     for (i = 0; i < blockSize; i++, npeMemAddress++) {
547 	if (npe_ins_write(sc, npeMemAddress, bp->data[i], verify) != 0) {
548 	    printf("%s: NPE instruction write failed", sc->sc_dev.dv_xname);
549 	    return EIO;
550 	}
551     }
552     return 0;
553 }
554 
555 static int
556 npe_load_data(struct ixpnpe_softc *sc,
557     const IxNpeDlNpeMgrCodeBlock *bp, int verify)
558 {
559     uint32_t npeMemAddress;
560     int i, blockSize;
561 
562     npeMemAddress = bp->npeMemAddress;
563     blockSize = bp->size;		/* NB: instruction/data count */
564     if (npeMemAddress + blockSize > sc->dataMemSize) {
565 	printf("%s: Block size too big for NPE memory\n", sc->sc_dev.dv_xname);
566 	return EINVAL;
567     }
568     for (i = 0; i < blockSize; i++, npeMemAddress++) {
569 	if (npe_data_write(sc, npeMemAddress, bp->data[i], verify) != 0) {
570 	    printf("%s: NPE data write failed\n", sc->sc_dev.dv_xname);
571 	    return EIO;
572 	}
573     }
574     return 0;
575 }
576 
577 static int
578 npe_load_stateinfo(struct ixpnpe_softc *sc,
579     const IxNpeDlNpeMgrStateInfoBlock *bp, int verify)
580 {
581     int i, nentries, error;
582 
583     npe_cpu_step_save(sc);
584 
585     /* for each state-info context register entry in block */
586     nentries = bp->size / IX_NPEDL_STATE_INFO_ENTRY_SIZE;
587     error = 0;
588     for (i = 0; i < nentries; i++) {
589 	/* each state-info entry is 2 words (address, value) in length */
590 	uint32_t regVal = bp->ctxtRegEntry[i].value;
591 	uint32_t addrInfo = bp->ctxtRegEntry[i].addressInfo;
592 
593 	uint32_t reg = (addrInfo & IX_NPEDL_MASK_STATE_ADDR_CTXT_REG);
594 	uint32_t cNum = (addrInfo & IX_NPEDL_MASK_STATE_ADDR_CTXT_NUM) >>
595 	    IX_NPEDL_OFFSET_STATE_ADDR_CTXT_NUM;
596 
597 	/* error-check Context Register No. and Context Number values  */
598 	if (!(0 <= reg && reg < IX_NPEDL_CTXT_REG_MAX)) {
599 	    printf("%s: invalid Context Register %u\n", sc->sc_dev.dv_xname,
600 		reg);
601 	    error = EINVAL;
602 	    break;
603 	}
604 	if (!(0 <= cNum && cNum < IX_NPEDL_CTXT_NUM_MAX)) {
605 	    printf("%s: invalid Context Number %u\n", sc->sc_dev.dv_xname,
606 	        cNum);
607 	    error = EINVAL;
608 	    break;
609 	}
610 	/* NOTE that there is no STEVT register for Context 0 */
611 	if (cNum == 0 && reg == IX_NPEDL_CTXT_REG_STEVT) {
612 	    printf("%s: no STEVT for Context 0\n", sc->sc_dev.dv_xname);
613 	    error = EINVAL;
614 	    break;
615 	}
616 
617 	if (npe_ctx_reg_write(sc, cNum, reg, regVal, verify) != 0) {
618 	    printf("%s: write of state-info to NPE failed\n",
619 	        sc->sc_dev.dv_xname);
620 	    error = EIO;
621 	    break;
622 	}
623     }
624 
625     npe_cpu_step_restore(sc);
626     return error;
627 }
628 
629 static int
630 npe_load_image(struct ixpnpe_softc *sc,
631     const uint32_t *imageCodePtr, int verify)
632 {
633 #define	EOM(marker)	((marker) == IX_NPEDL_END_OF_DOWNLOAD_MAP)
634     const IxNpeDlNpeMgrDownloadMap *downloadMap;
635     int i, error;
636 
637     if (!npe_isstopped(sc)) {		/* verify NPE is stopped */
638 	printf("%s: cannot load image, NPE not stopped\n", sc->sc_dev.dv_xname);
639 	return EIO;
640     }
641 
642     /*
643      * Read Download Map, checking each block type and calling
644      * appropriate function to perform download
645      */
646     error = 0;
647     downloadMap = (const IxNpeDlNpeMgrDownloadMap *) imageCodePtr;
648     for (i = 0; !EOM(downloadMap->entry[i].eodmMarker); i++) {
649 	/* calculate pointer to block to be downloaded */
650 	const uint32_t *bp = imageCodePtr + downloadMap->entry[i].block.offset;
651 	switch (downloadMap->entry[i].block.type) {
652 	case IX_NPEDL_BLOCK_TYPE_INSTRUCTION:
653 	    error = npe_load_ins(sc,
654 			 (const IxNpeDlNpeMgrCodeBlock *) bp, verify);
655 	    DPRINTF(sc->sc_dev, "%s: inst, error %d\n", __func__, error);
656 	    break;
657 	case IX_NPEDL_BLOCK_TYPE_DATA:
658 	    error = npe_load_data(sc,
659 			 (const IxNpeDlNpeMgrCodeBlock *) bp, verify);
660 	    DPRINTF(sc->sc_dev, "%s: data, error %d\n", __func__, error);
661 	    break;
662 	case IX_NPEDL_BLOCK_TYPE_STATE:
663 	    error = npe_load_stateinfo(sc,
664 			 (const IxNpeDlNpeMgrStateInfoBlock *) bp, verify);
665 	    DPRINTF(sc->sc_dev, "%s: state, error %d\n", __func__, error);
666 	    break;
667 	default:
668 	    printf("%s: unknown block type 0x%x in download map\n",
669 		sc->sc_dev.dv_xname, downloadMap->entry[i].block.type);
670 	    error = EIO;		/* XXX */
671 	    break;
672 	}
673 	if (error != 0)
674 	    break;
675     }
676     return error;
677 #undef EOM
678 }
679 
680 /* contains Reset values for Context Store Registers  */
681 static const struct {
682     uint32_t regAddr;
683     uint32_t regResetVal;
684 } ixNpeDlEcsRegResetValues[] = {
685     { IX_NPEDL_ECS_BG_CTXT_REG_0,    IX_NPEDL_ECS_BG_CTXT_REG_0_RESET },
686     { IX_NPEDL_ECS_BG_CTXT_REG_1,    IX_NPEDL_ECS_BG_CTXT_REG_1_RESET },
687     { IX_NPEDL_ECS_BG_CTXT_REG_2,    IX_NPEDL_ECS_BG_CTXT_REG_2_RESET },
688     { IX_NPEDL_ECS_PRI_1_CTXT_REG_0, IX_NPEDL_ECS_PRI_1_CTXT_REG_0_RESET },
689     { IX_NPEDL_ECS_PRI_1_CTXT_REG_1, IX_NPEDL_ECS_PRI_1_CTXT_REG_1_RESET },
690     { IX_NPEDL_ECS_PRI_1_CTXT_REG_2, IX_NPEDL_ECS_PRI_1_CTXT_REG_2_RESET },
691     { IX_NPEDL_ECS_PRI_2_CTXT_REG_0, IX_NPEDL_ECS_PRI_2_CTXT_REG_0_RESET },
692     { IX_NPEDL_ECS_PRI_2_CTXT_REG_1, IX_NPEDL_ECS_PRI_2_CTXT_REG_1_RESET },
693     { IX_NPEDL_ECS_PRI_2_CTXT_REG_2, IX_NPEDL_ECS_PRI_2_CTXT_REG_2_RESET },
694     { IX_NPEDL_ECS_DBG_CTXT_REG_0,   IX_NPEDL_ECS_DBG_CTXT_REG_0_RESET },
695     { IX_NPEDL_ECS_DBG_CTXT_REG_1,   IX_NPEDL_ECS_DBG_CTXT_REG_1_RESET },
696     { IX_NPEDL_ECS_DBG_CTXT_REG_2,   IX_NPEDL_ECS_DBG_CTXT_REG_2_RESET },
697     { IX_NPEDL_ECS_INSTRUCT_REG,     IX_NPEDL_ECS_INSTRUCT_REG_RESET }
698 };
699 
700 /* contains Reset values for Context Store Registers  */
701 static const uint32_t ixNpeDlCtxtRegResetValues[] = {
702     IX_NPEDL_CTXT_REG_RESET_STEVT,
703     IX_NPEDL_CTXT_REG_RESET_STARTPC,
704     IX_NPEDL_CTXT_REG_RESET_REGMAP,
705     IX_NPEDL_CTXT_REG_RESET_CINDEX,
706 };
707 
708 #define	IX_NPEDL_RESET_NPE_PARITY	0x0800
709 #define	IX_NPEDL_PARITY_BIT_MASK	0x3F00FFFF
710 #define	IX_NPEDL_CONFIG_CTRL_REG_MASK	0x3F3FFFFF
711 
712 static int
713 npe_cpu_reset(struct ixpnpe_softc *sc)
714 {
715 #define	N(a)	(sizeof(a) / sizeof(a[0]))
716     uint32_t ctxtReg; /* identifies Context Store reg (0-3) */
717     uint32_t regAddr;
718     uint32_t regVal;
719     uint32_t resetNpeParity;
720     uint32_t ixNpeConfigCtrlRegVal;
721     int i, error = 0;
722 
723     /* pre-store the NPE Config Control Register Value */
724     ixNpeConfigCtrlRegVal = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_CTL);
725     ixNpeConfigCtrlRegVal |= 0x3F000000;
726 
727     /* disable the parity interrupt */
728     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_CTL,
729 	(ixNpeConfigCtrlRegVal & IX_NPEDL_PARITY_BIT_MASK));
730     DPRINTFn(2, sc->sc_dev, "%s: dis parity int, CTL => 0x%x\n",
731 	__func__, ixNpeConfigCtrlRegVal & IX_NPEDL_PARITY_BIT_MASK);
732 
733     npe_cpu_step_save(sc);
734 
735     /*
736      * Clear the FIFOs.
737      */
738     while (npe_checkbits(sc,
739 	  IX_NPEDL_REG_OFFSET_WFIFO, IX_NPEDL_MASK_WFIFO_VALID)) {
740 	/* read from the Watch-point FIFO until empty */
741 	(void) npe_reg_read(sc, IX_NPEDL_REG_OFFSET_WFIFO);
742     }
743 
744     while (npe_checkbits(sc,
745 	  IX_NPEDL_REG_OFFSET_STAT, IX_NPEDL_MASK_STAT_OFNE)) {
746 	/* read from the outFIFO until empty */
747 	(void) npe_reg_read(sc, IX_NPEDL_REG_OFFSET_FIFO);
748     }
749 
750     while (npe_checkbits(sc,
751 	  IX_NPEDL_REG_OFFSET_STAT, IX_NPEDL_MASK_STAT_IFNE)) {
752 	/*
753 	 * Step execution of the NPE intruction to read inFIFO using
754 	 * the Debug Executing Context stack.
755 	 */
756 	error = npe_cpu_step(sc, IX_NPEDL_INSTR_RD_FIFO, 0, 0);
757 	if (error != 0) {
758 	    DPRINTF(sc->sc_dev, "%s: cannot step (1), error %u\n",
759 		__func__, error);
760 	    npe_cpu_step_restore(sc);
761 	    return error;
762 	}
763     }
764 
765     /*
766      * Reset the mailbox reg
767      */
768     /* ...from XScale side */
769     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_MBST, IX_NPEDL_REG_RESET_MBST);
770     /* ...from NPE side */
771     error = npe_cpu_step(sc, IX_NPEDL_INSTR_RESET_MBOX, 0, 0);
772     if (error != 0) {
773 	DPRINTF(sc->sc_dev, "%s: cannot step (2), error %u\n", __func__, error);
774 	npe_cpu_step_restore(sc);
775         return error;
776     }
777 
778     /*
779      * Reset the physical registers in the NPE register file:
780      * Note: no need to save/restore REGMAP for Context 0 here
781      * since all Context Store regs are reset in subsequent code.
782      */
783     for (regAddr = 0;
784 	 regAddr < IX_NPEDL_TOTAL_NUM_PHYS_REG && error == 0;
785 	 regAddr++) {
786 	/* for each physical register in the NPE reg file, write 0 : */
787 	error = npe_physical_reg_write(sc, regAddr, 0, true);
788 	if (error != 0) {
789 	    DPRINTF(sc->sc_dev, "%s: cannot write phy reg, error %u\n",
790 		__func__, error);
791 	    npe_cpu_step_restore(sc);
792 	    return error;		/* abort reset */
793 	}
794     }
795 
796     /*
797      * Reset the context store:
798      */
799     for (i = IX_NPEDL_CTXT_NUM_MIN; i <= IX_NPEDL_CTXT_NUM_MAX; i++) {
800 	/* set each context's Context Store registers to reset values: */
801 	for (ctxtReg = 0; ctxtReg < IX_NPEDL_CTXT_REG_MAX; ctxtReg++) {
802 	    /* NOTE that there is no STEVT register for Context 0 */
803 	    if (!(i == 0 && ctxtReg == IX_NPEDL_CTXT_REG_STEVT)) {
804 		regVal = ixNpeDlCtxtRegResetValues[ctxtReg];
805 		error = npe_ctx_reg_write(sc, i, ctxtReg, regVal, true);
806 		if (error != 0) {
807 		    DPRINTF(sc->sc_dev, "%s: cannot write ctx reg, error %u\n",
808 			__func__, error);
809 		    npe_cpu_step_restore(sc);
810 		    return error;	 /* abort reset */
811 		}
812 	    }
813 	}
814     }
815 
816     npe_cpu_step_restore(sc);
817 
818     /* write Reset values to Execution Context Stack registers */
819     for (i = 0; i < N(ixNpeDlEcsRegResetValues); i++)
820 	npe_ecs_reg_write(sc,
821 	    ixNpeDlEcsRegResetValues[i].regAddr,
822 	    ixNpeDlEcsRegResetValues[i].regResetVal);
823 
824     /* clear the profile counter */
825     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_CLR_PROFILE_CNT);
826 
827     /* clear registers EXCT, AP0, AP1, AP2 and AP3 */
828     for (regAddr = IX_NPEDL_REG_OFFSET_EXCT;
829 	 regAddr <= IX_NPEDL_REG_OFFSET_AP3;
830 	 regAddr += sizeof(uint32_t))
831 	npe_reg_write(sc, regAddr, 0);
832 
833     /* Reset the Watch-count register */
834     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_WC, 0);
835 
836     /*
837      * WR IXA00055043 - Remove IMEM Parity Introduced by NPE Reset Operation
838      */
839 
840     /*
841      * Reset the NPE and its coprocessor - to reset internal
842      * states and remove parity error.  Note this makes no
843      * sense based on the documentation.  The feature control
844      * register always reads back as 0 on the ixp425 and further
845      * the bit definition of NPEA/NPEB is off by 1 according to
846      * the Intel documention--so we're blindly following the
847      * Intel code w/o any real understanding.
848      */
849     regVal = EXP_BUS_READ_4(ixp425_softc, EXP_FCTRL_OFFSET);
850     DPRINTFn(2, sc->sc_dev, "%s: FCTRL 0x%x\n", __func__, regVal);
851     resetNpeParity =
852 	IX_NPEDL_RESET_NPE_PARITY << (1 + sc->sc_unit);
853     DPRINTFn(2, sc->sc_dev, "%s: FCTRL fuse parity, write 0x%x\n",
854 	__func__, regVal | resetNpeParity);
855     EXP_BUS_WRITE_4(ixp425_softc, EXP_FCTRL_OFFSET, regVal | resetNpeParity);
856 
857     /* un-fuse and un-reset the NPE & coprocessor */
858     DPRINTFn(2, sc->sc_dev, "%s: FCTRL unfuse parity, write 0x%x\n",
859 	__func__, regVal & ~resetNpeParity);
860     EXP_BUS_WRITE_4(ixp425_softc, EXP_FCTRL_OFFSET, regVal &~ resetNpeParity);
861 
862     /*
863      * Call NpeMgr function to stop the NPE again after the Feature Control
864      * has unfused and Un-Reset the NPE and its associated Coprocessors.
865      */
866     error = npe_cpu_stop(sc);
867 
868     /* restore NPE configuration bus Control Register - Parity Settings  */
869     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_CTL,
870         (ixNpeConfigCtrlRegVal & IX_NPEDL_CONFIG_CTRL_REG_MASK));
871     DPRINTFn(2, sc->sc_dev, "%s: restore CTL => 0x%x\n",
872 	__func__, npe_reg_read(sc, IX_NPEDL_REG_OFFSET_CTL));
873 
874     return error;
875 #undef N
876 }
877 
878 static int
879 npe_cpu_start(struct ixpnpe_softc *sc)
880 {
881     uint32_t ecsRegVal;
882 
883     /*
884      * Ensure only Background Context Stack Level is Active by turning off
885      * the Active bit in each of the other Executing Context Stack levels.
886      */
887     ecsRegVal = npe_ecs_reg_read(sc, IX_NPEDL_ECS_PRI_1_CTXT_REG_0);
888     ecsRegVal &= ~IX_NPEDL_MASK_ECS_REG_0_ACTIVE;
889     npe_ecs_reg_write(sc, IX_NPEDL_ECS_PRI_1_CTXT_REG_0, ecsRegVal);
890 
891     ecsRegVal = npe_ecs_reg_read(sc, IX_NPEDL_ECS_PRI_2_CTXT_REG_0);
892     ecsRegVal &= ~IX_NPEDL_MASK_ECS_REG_0_ACTIVE;
893     npe_ecs_reg_write(sc, IX_NPEDL_ECS_PRI_2_CTXT_REG_0, ecsRegVal);
894 
895     ecsRegVal = npe_ecs_reg_read(sc, IX_NPEDL_ECS_DBG_CTXT_REG_0);
896     ecsRegVal &= ~IX_NPEDL_MASK_ECS_REG_0_ACTIVE;
897     npe_ecs_reg_write(sc, IX_NPEDL_ECS_DBG_CTXT_REG_0, ecsRegVal);
898 
899     /* clear the pipeline */
900     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_NPE_CLR_PIPE);
901 
902     /* start NPE execution by issuing command through EXCTL register on NPE */
903     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_NPE_START);
904 
905     /*
906      * Check execution status of NPE to verify operation was successful.
907      */
908     return npe_checkbits(sc,
909 	IX_NPEDL_REG_OFFSET_EXCTL, IX_NPEDL_EXCTL_STATUS_RUN) ? 0 : EIO;
910 }
911 
912 static int
913 npe_cpu_stop(struct ixpnpe_softc *sc)
914 {
915     /* stop NPE execution by issuing command through EXCTL register on NPE */
916     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_NPE_STOP);
917 
918     /* verify that NPE Stop was successful */
919     return npe_checkbits(sc,
920 	IX_NPEDL_REG_OFFSET_EXCTL, IX_NPEDL_EXCTL_STATUS_STOP) ? 0 : EIO;
921 }
922 
923 #define IX_NPEDL_REG_SIZE_BYTE            8
924 #define IX_NPEDL_REG_SIZE_SHORT           16
925 #define IX_NPEDL_REG_SIZE_WORD            32
926 
927 /*
928  * Introduce extra read cycles after issuing read command to NPE
929  * so that we read the register after the NPE has updated it
930  * This is to overcome race condition between XScale and NPE
931  */
932 #define IX_NPEDL_DELAY_READ_CYCLES        2
933 /*
934  * To mask top three MSBs of 32bit word to download into NPE IMEM
935  */
936 #define IX_NPEDL_MASK_UNUSED_IMEM_BITS    0x1FFFFFFF;
937 
938 static void
939 npe_cmd_issue_write(struct ixpnpe_softc *sc,
940     uint32_t cmd, uint32_t addr, uint32_t data)
941 {
942     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXDATA, data);
943     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXAD, addr);
944     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXCTL, cmd);
945 }
946 
947 static uint32_t
948 npe_cmd_issue_read(struct ixpnpe_softc *sc, uint32_t cmd, uint32_t addr)
949 {
950     uint32_t data;
951     int i;
952 
953     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXAD, addr);
954     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXCTL, cmd);
955     for (i = 0; i <= IX_NPEDL_DELAY_READ_CYCLES; i++)
956 	data = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_EXDATA);
957     return data;
958 }
959 
960 static int
961 npe_ins_write(struct ixpnpe_softc *sc, uint32_t addr, uint32_t data, int verify)
962 {
963     DPRINTFn(4, sc->sc_dev, "%s(0x%x, 0x%x)\n", __func__, addr, data);
964     npe_cmd_issue_write(sc, IX_NPEDL_EXCTL_CMD_WR_INS_MEM, addr, data);
965     if (verify) {
966 	uint32_t rdata;
967 
968         /*
969 	 * Write invalid data to this reg, so we can see if we're reading
970 	 * the EXDATA register too early.
971 	 */
972 	npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXDATA, ~data);
973 
974         /* Disabled since top 3 MSB are not used for Azusa hardware Refer WR:IXA00053900*/
975         data &= IX_NPEDL_MASK_UNUSED_IMEM_BITS;
976 
977         rdata = npe_cmd_issue_read(sc, IX_NPEDL_EXCTL_CMD_RD_INS_MEM, addr);
978         rdata &= IX_NPEDL_MASK_UNUSED_IMEM_BITS;
979 
980 	if (data != rdata)
981 	    return EIO;
982     }
983     return 0;
984 }
985 
986 static int
987 npe_data_write(struct ixpnpe_softc *sc, uint32_t addr, uint32_t data, int verify)
988 {
989     DPRINTFn(4, sc->sc_dev, "%s(0x%x, 0x%x)\n", __func__, addr, data);
990     npe_cmd_issue_write(sc, IX_NPEDL_EXCTL_CMD_WR_DATA_MEM, addr, data);
991     if (verify) {
992         /*
993 	 * Write invalid data to this reg, so we can see if we're reading
994 	 * the EXDATA register too early.
995 	 */
996 	npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXDATA, ~data);
997 	if (data != npe_cmd_issue_read(sc, IX_NPEDL_EXCTL_CMD_RD_DATA_MEM, addr))
998 	    return EIO;
999     }
1000     return 0;
1001 }
1002 
1003 static void
1004 npe_ecs_reg_write(struct ixpnpe_softc *sc, uint32_t reg, uint32_t data)
1005 {
1006     npe_cmd_issue_write(sc, IX_NPEDL_EXCTL_CMD_WR_ECS_REG, reg, data);
1007 }
1008 
1009 static uint32_t
1010 npe_ecs_reg_read(struct ixpnpe_softc *sc, uint32_t reg)
1011 {
1012     return npe_cmd_issue_read(sc, IX_NPEDL_EXCTL_CMD_RD_ECS_REG, reg);
1013 }
1014 
1015 static void
1016 npe_issue_cmd(struct ixpnpe_softc *sc, uint32_t command)
1017 {
1018     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXCTL, command);
1019 }
1020 
1021 static void
1022 npe_cpu_step_save(struct ixpnpe_softc *sc)
1023 {
1024     /* turn off the halt bit by clearing Execution Count register. */
1025     /* save reg contents 1st and restore later */
1026     sc->savedExecCount = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_EXCT);
1027     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXCT, 0);
1028 
1029     /* ensure that IF and IE are on (temporarily), so that we don't end up
1030      * stepping forever */
1031     sc->savedEcsDbgCtxtReg2 = npe_ecs_reg_read(sc, IX_NPEDL_ECS_DBG_CTXT_REG_2);
1032 
1033     npe_ecs_reg_write(sc, IX_NPEDL_ECS_DBG_CTXT_REG_2,
1034 	(sc->savedEcsDbgCtxtReg2 | IX_NPEDL_MASK_ECS_DBG_REG_2_IF |
1035 	 IX_NPEDL_MASK_ECS_DBG_REG_2_IE));
1036 }
1037 
1038 static int
1039 npe_cpu_step(struct ixpnpe_softc *sc, uint32_t npeInstruction,
1040     uint32_t ctxtNum, uint32_t ldur)
1041 {
1042 #define	IX_NPE_DL_MAX_NUM_OF_RETRIES	1000000
1043     uint32_t ecsDbgRegVal;
1044     uint32_t oldWatchcount, newWatchcount;
1045     int tries;
1046 
1047     /* set the Active bit, and the LDUR, in the debug level */
1048     ecsDbgRegVal = IX_NPEDL_MASK_ECS_REG_0_ACTIVE |
1049 	(ldur << IX_NPEDL_OFFSET_ECS_REG_0_LDUR);
1050 
1051     npe_ecs_reg_write(sc, IX_NPEDL_ECS_DBG_CTXT_REG_0, ecsDbgRegVal);
1052 
1053     /*
1054      * Set CCTXT at ECS DEBUG L3 to specify in which context to execute the
1055      * instruction, and set SELCTXT at ECS DEBUG Level to specify which context
1056      * store to access.
1057      * Debug ECS Level Reg 1 has form  0x000n000n, where n = context number
1058      */
1059     ecsDbgRegVal = (ctxtNum << IX_NPEDL_OFFSET_ECS_REG_1_CCTXT) |
1060 	(ctxtNum << IX_NPEDL_OFFSET_ECS_REG_1_SELCTXT);
1061 
1062     npe_ecs_reg_write(sc, IX_NPEDL_ECS_DBG_CTXT_REG_1, ecsDbgRegVal);
1063 
1064     /* clear the pipeline */
1065     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_NPE_CLR_PIPE);
1066 
1067     /* load NPE instruction into the instruction register */
1068     npe_ecs_reg_write(sc, IX_NPEDL_ECS_INSTRUCT_REG, npeInstruction);
1069 
1070     /* we need this value later to wait for completion of NPE execution step */
1071     oldWatchcount = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_WC);
1072 
1073     /* issue a Step One command via the Execution Control register */
1074     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_NPE_STEP);
1075 
1076     /*
1077      * Force the XScale to wait until the NPE has finished execution step
1078      * NOTE that this delay will be very small, just long enough to allow a
1079      * single NPE instruction to complete execution; if instruction execution
1080      * is not completed before timeout retries, exit the while loop.
1081      */
1082     newWatchcount = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_WC);
1083     for (tries = 0; tries < IX_NPE_DL_MAX_NUM_OF_RETRIES &&
1084         newWatchcount == oldWatchcount; tries++) {
1085 	/* Watch Count register increments when NPE completes an instruction */
1086 	newWatchcount = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_WC);
1087     }
1088     return (tries < IX_NPE_DL_MAX_NUM_OF_RETRIES) ? 0 : EIO;
1089 #undef IX_NPE_DL_MAX_NUM_OF_RETRIES
1090 }
1091 
1092 static void
1093 npe_cpu_step_restore(struct ixpnpe_softc *sc)
1094 {
1095     /* clear active bit in debug level */
1096     npe_ecs_reg_write(sc, IX_NPEDL_ECS_DBG_CTXT_REG_0, 0);
1097 
1098     /* clear the pipeline */
1099     npe_issue_cmd(sc, IX_NPEDL_EXCTL_CMD_NPE_CLR_PIPE);
1100 
1101     /* restore Execution Count register contents. */
1102     npe_reg_write(sc, IX_NPEDL_REG_OFFSET_EXCT, sc->savedExecCount);
1103 
1104     /* restore IF and IE bits to original values */
1105     npe_ecs_reg_write(sc, IX_NPEDL_ECS_DBG_CTXT_REG_2, sc->savedEcsDbgCtxtReg2);
1106 }
1107 
1108 static int
1109 npe_logical_reg_read(struct ixpnpe_softc *sc,
1110     uint32_t regAddr, uint32_t regSize,
1111     uint32_t ctxtNum, uint32_t *regVal)
1112 {
1113     uint32_t npeInstruction, mask;
1114     int error;
1115 
1116     switch (regSize) {
1117     case IX_NPEDL_REG_SIZE_BYTE:
1118 	npeInstruction = IX_NPEDL_INSTR_RD_REG_BYTE;
1119 	mask = 0xff;
1120 	break;
1121     case IX_NPEDL_REG_SIZE_SHORT:
1122 	npeInstruction = IX_NPEDL_INSTR_RD_REG_SHORT;
1123 	mask = 0xffff;
1124 	break;
1125     case IX_NPEDL_REG_SIZE_WORD:
1126 	npeInstruction = IX_NPEDL_INSTR_RD_REG_WORD;
1127 	mask = 0xffffffff;
1128 	break;
1129     default:
1130 	return EINVAL;
1131     }
1132 
1133     /* make regAddr be the SRC and DEST operands (e.g. movX d0, d0) */
1134     npeInstruction |= (regAddr << IX_NPEDL_OFFSET_INSTR_SRC) |
1135 	(regAddr << IX_NPEDL_OFFSET_INSTR_DEST);
1136 
1137     /* step execution of NPE intruction using Debug Executing Context stack */
1138     error = npe_cpu_step(sc, npeInstruction, ctxtNum, IX_NPEDL_RD_INSTR_LDUR);
1139     if (error != 0) {
1140 	DPRINTF(sc->sc_dev, "%s(0x%x, %u, %u), cannot step, error %d\n",
1141 	    __func__, regAddr, regSize, ctxtNum, error);
1142 	return error;
1143     }
1144     /* read value of register from Execution Data register */
1145     *regVal = npe_reg_read(sc, IX_NPEDL_REG_OFFSET_EXDATA);
1146 
1147     /* align value from left to right */
1148     *regVal = (*regVal >> (IX_NPEDL_REG_SIZE_WORD - regSize)) & mask;
1149 
1150     return 0;
1151 }
1152 
1153 static int
1154 npe_logical_reg_write(struct ixpnpe_softc *sc, uint32_t regAddr, uint32_t regVal,
1155     uint32_t regSize, uint32_t ctxtNum, int verify)
1156 {
1157     int error;
1158 
1159     DPRINTFn(4, sc->sc_dev, "%s(0x%x, 0x%x, %u, %u)\n",
1160 	__func__, regAddr, regVal, regSize, ctxtNum);
1161     if (regSize == IX_NPEDL_REG_SIZE_WORD) {
1162 	/* NPE register addressing is left-to-right: e.g. |d0|d1|d2|d3| */
1163 	/* Write upper half-word (short) to |d0|d1| */
1164 	error = npe_logical_reg_write(sc, regAddr,
1165 		     regVal >> IX_NPEDL_REG_SIZE_SHORT,
1166 		     IX_NPEDL_REG_SIZE_SHORT, ctxtNum, verify);
1167 	if (error != 0)
1168 	    return error;
1169 
1170 	/* Write lower half-word (short) to |d2|d3| */
1171 	error = npe_logical_reg_write(sc,
1172 		     regAddr + sizeof(uint16_t),
1173 		     regVal & 0xffff,
1174 		     IX_NPEDL_REG_SIZE_SHORT, ctxtNum, verify);
1175     } else {
1176 	uint32_t npeInstruction;
1177 
1178         switch (regSize) {
1179 	case IX_NPEDL_REG_SIZE_BYTE:
1180 	    npeInstruction = IX_NPEDL_INSTR_WR_REG_BYTE;
1181 	    regVal &= 0xff;
1182 	    break;
1183 	case IX_NPEDL_REG_SIZE_SHORT:
1184             npeInstruction = IX_NPEDL_INSTR_WR_REG_SHORT;
1185 	    regVal &= 0xffff;
1186 	    break;
1187 	default:
1188 	    return EINVAL;
1189 	}
1190 	/* fill dest operand field of  instruction with destination reg addr */
1191 	npeInstruction |= (regAddr << IX_NPEDL_OFFSET_INSTR_DEST);
1192 
1193 	/* fill src operand field of instruction with least-sig 5 bits of val*/
1194 	npeInstruction |= ((regVal & IX_NPEDL_MASK_IMMED_INSTR_SRC_DATA) <<
1195 			   IX_NPEDL_OFFSET_INSTR_SRC);
1196 
1197 	/* fill coprocessor field of instruction with most-sig 11 bits of val*/
1198 	npeInstruction |= ((regVal & IX_NPEDL_MASK_IMMED_INSTR_COPROC_DATA) <<
1199 			   IX_NPEDL_DISPLACE_IMMED_INSTR_COPROC_DATA);
1200 
1201 	/* step execution of NPE intruction using Debug ECS */
1202 	error = npe_cpu_step(sc, npeInstruction,
1203 					  ctxtNum, IX_NPEDL_WR_INSTR_LDUR);
1204     }
1205     if (error != 0) {
1206 	DPRINTF(sc->sc_dev, "%s(0x%x, 0x%x, %u, %u), error %u writing reg\n",
1207 	    __func__, regAddr, regVal, regSize, ctxtNum, error);
1208 	return error;
1209     }
1210     if (verify) {
1211 	uint32_t retRegVal;
1212 
1213     	error = npe_logical_reg_read(sc, regAddr, regSize, ctxtNum, &retRegVal);
1214         if (error == 0 && regVal != retRegVal)
1215 	    error = EIO;	/* XXX ambiguous */
1216     }
1217     return error;
1218 }
1219 
1220 /*
1221  * There are 32 physical registers used in an NPE.  These are
1222  * treated as 16 pairs of 32-bit registers.  To write one of the pair,
1223  * write the pair number (0-16) to the REGMAP for Context 0.  Then write
1224  * the value to register  0 or 4 in the regfile, depending on which
1225  * register of the pair is to be written
1226  */
1227 static int
1228 npe_physical_reg_write(struct ixpnpe_softc *sc,
1229     uint32_t regAddr, uint32_t regValue, int verify)
1230 {
1231     int error;
1232 
1233     /*
1234      * Set REGMAP for context 0 to (regAddr >> 1) to choose which pair (0-16)
1235      * of physical registers to write .
1236      */
1237     error = npe_logical_reg_write(sc, IX_NPEDL_CTXT_REG_ADDR_REGMAP,
1238 	       (regAddr >> IX_NPEDL_OFFSET_PHYS_REG_ADDR_REGMAP),
1239 	       IX_NPEDL_REG_SIZE_SHORT, 0, verify);
1240     if (error == 0) {
1241 	/* regAddr = 0 or 4  */
1242 	regAddr = (regAddr & IX_NPEDL_MASK_PHYS_REG_ADDR_LOGICAL_ADDR) *
1243 	    sizeof(uint32_t);
1244 	error = npe_logical_reg_write(sc, regAddr, regValue,
1245 	    IX_NPEDL_REG_SIZE_WORD, 0, verify);
1246     }
1247     return error;
1248 }
1249 
1250 static int
1251 npe_ctx_reg_write(struct ixpnpe_softc *sc, uint32_t ctxtNum,
1252     uint32_t ctxtReg, uint32_t ctxtRegVal, int verify)
1253 {
1254     DPRINTFn(4, sc->sc_dev, "%s(%u, %u, %u)\n",
1255 	__func__, ctxtNum, ctxtReg, ctxtRegVal);
1256     /*
1257      * Context 0 has no STARTPC. Instead, this value is used to set
1258      * NextPC for Background ECS, to set where NPE starts executing code
1259      */
1260     if (ctxtNum == 0 && ctxtReg == IX_NPEDL_CTXT_REG_STARTPC) {
1261 	/* read BG_CTXT_REG_0, update NEXTPC bits, and write back to reg */
1262 	uint32_t v = npe_ecs_reg_read(sc, IX_NPEDL_ECS_BG_CTXT_REG_0);
1263 	v &= ~IX_NPEDL_MASK_ECS_REG_0_NEXTPC;
1264 	v |= (ctxtRegVal << IX_NPEDL_OFFSET_ECS_REG_0_NEXTPC) &
1265 	    IX_NPEDL_MASK_ECS_REG_0_NEXTPC;
1266 
1267 	npe_ecs_reg_write(sc, IX_NPEDL_ECS_BG_CTXT_REG_0, v);
1268 	return 0;
1269     } else {
1270 	static const struct {
1271 	    uint32_t regAddress;
1272 	    uint32_t regSize;
1273 	} regAccInfo[IX_NPEDL_CTXT_REG_MAX] = {
1274 	    { IX_NPEDL_CTXT_REG_ADDR_STEVT,	IX_NPEDL_REG_SIZE_BYTE },
1275 	    { IX_NPEDL_CTXT_REG_ADDR_STARTPC,	IX_NPEDL_REG_SIZE_SHORT },
1276 	    { IX_NPEDL_CTXT_REG_ADDR_REGMAP,	IX_NPEDL_REG_SIZE_SHORT },
1277 	    { IX_NPEDL_CTXT_REG_ADDR_CINDEX,	IX_NPEDL_REG_SIZE_BYTE }
1278 	};
1279 	return npe_logical_reg_write(sc, regAccInfo[ctxtReg].regAddress,
1280 		ctxtRegVal, regAccInfo[ctxtReg].regSize, ctxtNum, verify);
1281     }
1282 }
1283 
1284 /*
1285  * NPE Mailbox support.
1286  */
1287 #define	IX_NPEMH_MAXTRIES	100000
1288 
1289 static int
1290 ixpnpe_ofifo_wait(struct ixpnpe_softc *sc)
1291 {
1292     int i;
1293 
1294     for (i = 0; i < IX_NPEMH_MAXTRIES; i++) {
1295         if (npe_reg_read(sc, IX_NPESTAT) & IX_NPESTAT_OFNE)
1296 	    return 1;
1297 	DELAY(10);
1298     }
1299     printf("%s: %s: timeout, last status 0x%x\n", sc->sc_dev.dv_xname,
1300         __func__, npe_reg_read(sc, IX_NPESTAT));
1301     return 0;
1302 }
1303 
1304 static int
1305 ixpnpe_intr(void *arg)
1306 {
1307     struct ixpnpe_softc *sc = arg;
1308     uint32_t status;
1309 
1310     status = npe_reg_read(sc, IX_NPESTAT);
1311     if ((status & IX_NPESTAT_OFINT) == 0) {
1312 	/* NB: should not happen */
1313 	printf("%s: %s: status 0x%x\n", sc->sc_dev.dv_xname, __func__, status);
1314 	/* XXX must silence interrupt? */
1315 	return(1);
1316     }
1317     /*
1318      * A message is waiting in the output FIFO, copy it so
1319      * the interrupt will be silenced; then signal anyone
1320      * waiting to collect the result.
1321      */
1322     sc->sc_msgwaiting = -1;		/* NB: error indicator */
1323     if (ixpnpe_ofifo_wait(sc)) {
1324 	sc->sc_msg[0] = npe_reg_read(sc, IX_NPEFIFO);
1325 	if (ixpnpe_ofifo_wait(sc)) {
1326 	    sc->sc_msg[1] = npe_reg_read(sc, IX_NPEFIFO);
1327 	    sc->sc_msgwaiting = 1;	/* successful fetch */
1328 	}
1329     }
1330     if (sc->sc_msg[0] == (NPE_MACRECOVERYSTART << NPE_MAC_MSGID_SHL)) {
1331 	    int s;
1332 
1333 	    s = splnet();
1334 	    delay(100); /* delay 100usec */
1335 	    if (sc->macresetcbfunc != NULL)
1336 		    sc->macresetcbfunc(sc->macresetcbarg);
1337 	    splx(s);
1338     }
1339 
1340 #if 0
1341     /* XXX Too dangerous! see ixpnpe_recvmsg_locked() */
1342     wakeup(sc);
1343 #endif
1344 
1345     return (1);
1346 }
1347 
1348 static int
1349 ixpnpe_ififo_wait(struct ixpnpe_softc *sc)
1350 {
1351     int i;
1352 
1353     for (i = 0; i < IX_NPEMH_MAXTRIES; i++) {
1354 	if (npe_reg_read(sc, IX_NPESTAT) & IX_NPESTAT_IFNF)
1355 	    return 1;
1356 	DELAY(10);
1357     }
1358     return 0;
1359 }
1360 
1361 static int
1362 ixpnpe_sendmsg_locked(struct ixpnpe_softc *sc, const uint32_t msg[2])
1363 {
1364     int error = 0;
1365 
1366     sc->sc_msgwaiting = 0;
1367     if (ixpnpe_ififo_wait(sc)) {
1368 	npe_reg_write(sc, IX_NPEFIFO, msg[0]);
1369 	if (ixpnpe_ififo_wait(sc))
1370 	    npe_reg_write(sc, IX_NPEFIFO, msg[1]);
1371 	else
1372 	    error = EIO;
1373     } else
1374 	error = EIO;
1375 
1376     if (error)
1377 	printf("%s: input FIFO timeout, msg [0x%x,0x%x]\n",
1378 	    sc->sc_dev.dv_xname, msg[0], msg[1]);
1379     return error;
1380 }
1381 
1382 static int
1383 ixpnpe_recvmsg_locked(struct ixpnpe_softc *sc, uint32_t msg[2])
1384 {
1385 
1386 	if (!sc->sc_msgwaiting) {
1387 		/* XXX interrupt context - cannot sleep */
1388 		delay(1000);	/* wait 1ms (is it ok?)*/
1389 	}
1390 	memcpy(msg, sc->sc_msg, sizeof(sc->sc_msg));
1391 	/* NB: sc_msgwaiting != 1 means the ack fetch failed */
1392 	return sc->sc_msgwaiting != 1 ? EIO : 0;
1393 }
1394 
1395 /*
1396  * Send a msg to the NPE and wait for a reply.  We use the
1397  * private mutex and sleep until an interrupt is received
1398  * signalling the availability of data in the output FIFO
1399  * so the caller cannot be holding a mutex.  May be better
1400  * piggyback on the caller's mutex instead but that would
1401  * make other locking confusing.
1402  */
1403 int
1404 ixpnpe_sendandrecvmsg(struct ixpnpe_softc *sc,
1405 	const uint32_t send[2], uint32_t recv[2])
1406 {
1407     int error;
1408 
1409     simple_lock(&sc->sc_lock);
1410     error = ixpnpe_sendmsg_locked(sc, send);
1411     if (error == 0)
1412 	error = ixpnpe_recvmsg_locked(sc, recv);
1413     simple_unlock(&sc->sc_lock);
1414 
1415     return error;
1416 }
1417 
1418 /* XXX temporary, not reliable */
1419 
1420 int
1421 ixpnpe_sendmsg(struct ixpnpe_softc *sc, const uint32_t msg[2])
1422 {
1423     int error;
1424 
1425     simple_lock(&sc->sc_lock);
1426     error = ixpnpe_sendmsg_locked(sc, msg);
1427     simple_unlock(&sc->sc_lock);
1428 
1429     return error;
1430 }
1431 
1432 int
1433 ixpnpe_recvmsg(struct ixpnpe_softc *sc, uint32_t msg[2])
1434 {
1435     int error;
1436 
1437     simple_lock(&sc->sc_lock);
1438     if (sc->sc_msgwaiting)
1439 	memcpy(msg, sc->sc_msg, sizeof(sc->sc_msg));
1440     /* NB: sc_msgwaiting != 1 means the ack fetch failed */
1441     error = sc->sc_msgwaiting != 1 ? EIO : 0;
1442     simple_unlock(&sc->sc_lock);
1443 
1444     return error;
1445 }
1446