1/*-
2 * Copyright (c) 2012 Olivier Houchard <cognet@FreeBSD.org>
3 * Copyright (c) 2011
4 *	Ben Gray <ben.r.gray@gmail.com>.
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 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. The name of the company nor the name of the author may be used to
16 *    endorse or promote products derived from this software without specific
17 *    prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY BEN GRAY ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL BEN GRAY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
25 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
26 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
27 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
28 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD$");
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/bus.h>
36#include <sys/kernel.h>
37#include <sys/rman.h>
38#include <sys/module.h>
39#include <sys/lock.h>
40#include <sys/mutex.h>
41#include <machine/intr.h>
42
43#include <machine/bus.h>
44#include <machine/pl310.h>
45
46#include <dev/fdt/fdt_common.h>
47#include <dev/ofw/openfirm.h>
48#include <dev/ofw/ofw_bus.h>
49#include <dev/ofw/ofw_bus_subr.h>
50
51/*
52 * Define this if you need to disable PL310 for debugging purpose
53 * Spec:
54 * http://infocenter.arm.com/help/topic/com.arm.doc.ddi0246e/DDI0246E_l2c310_r3p1_trm.pdf
55 */
56
57/*
58 * Hardcode errata for now
59 * http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0246b/pr01s02s02.html
60 */
61#define	PL310_ERRATA_588369
62#define	PL310_ERRATA_753970
63#define	PL310_ERRATA_727915
64
65#define	PL310_LOCK(sc) do {		\
66	mtx_lock_spin(&(sc)->sc_mtx);	\
67} while(0);
68
69#define	PL310_UNLOCK(sc) do {		\
70	mtx_unlock_spin(&(sc)->sc_mtx);	\
71} while(0);
72
73static int pl310_enabled = 1;
74TUNABLE_INT("hw.pl310.enabled", &pl310_enabled);
75
76static uint32_t g_l2cache_way_mask;
77
78static const uint32_t g_l2cache_line_size = 32;
79static const uint32_t g_l2cache_align_mask = (32 - 1);
80
81static uint32_t g_l2cache_size;
82static uint32_t g_way_size;
83static uint32_t g_ways_assoc;
84
85static struct pl310_softc *pl310_softc;
86
87static struct ofw_compat_data compat_data[] = {
88	{"arm,pl310",		true}, /* Non-standard, FreeBSD. */
89	{"arm,pl310-cache",	true},
90	{NULL,			false}
91};
92
93static void
94pl310_print_config(struct pl310_softc *sc)
95{
96	uint32_t aux, prefetch;
97	const char *dis = "disabled";
98	const char *ena = "enabled";
99
100	aux = pl310_read4(sc, PL310_AUX_CTRL);
101	prefetch = pl310_read4(sc, PL310_PREFETCH_CTRL);
102
103	device_printf(sc->sc_dev, "Early BRESP response: %s\n",
104		(aux & AUX_CTRL_EARLY_BRESP) ? ena : dis);
105	device_printf(sc->sc_dev, "Instruction prefetch: %s\n",
106		(aux & AUX_CTRL_INSTR_PREFETCH) ? ena : dis);
107	device_printf(sc->sc_dev, "Data prefetch: %s\n",
108		(aux & AUX_CTRL_DATA_PREFETCH) ? ena : dis);
109	device_printf(sc->sc_dev, "Non-secure interrupt control: %s\n",
110		(aux & AUX_CTRL_NS_INT_CTRL) ? ena : dis);
111	device_printf(sc->sc_dev, "Non-secure lockdown: %s\n",
112		(aux & AUX_CTRL_NS_LOCKDOWN) ? ena : dis);
113	device_printf(sc->sc_dev, "Share override: %s\n",
114		(aux & AUX_CTRL_SHARE_OVERRIDE) ? ena : dis);
115
116	device_printf(sc->sc_dev, "Double linefill: %s\n",
117		(prefetch & PREFETCH_CTRL_DL) ? ena : dis);
118	device_printf(sc->sc_dev, "Instruction prefetch: %s\n",
119		(prefetch & PREFETCH_CTRL_INSTR_PREFETCH) ? ena : dis);
120	device_printf(sc->sc_dev, "Data prefetch: %s\n",
121		(prefetch & PREFETCH_CTRL_DATA_PREFETCH) ? ena : dis);
122	device_printf(sc->sc_dev, "Double linefill on WRAP request: %s\n",
123		(prefetch & PREFETCH_CTRL_DL_ON_WRAP) ? ena : dis);
124	device_printf(sc->sc_dev, "Prefetch drop: %s\n",
125		(prefetch & PREFETCH_CTRL_PREFETCH_DROP) ? ena : dis);
126	device_printf(sc->sc_dev, "Incr double Linefill: %s\n",
127		(prefetch & PREFETCH_CTRL_INCR_DL) ? ena : dis);
128	device_printf(sc->sc_dev, "Not same ID on exclusive sequence: %s\n",
129		(prefetch & PREFETCH_CTRL_NOTSAMEID) ? ena : dis);
130	device_printf(sc->sc_dev, "Prefetch offset: %d\n",
131		(prefetch & PREFETCH_CTRL_OFFSET_MASK));
132}
133
134void
135pl310_set_ram_latency(struct pl310_softc *sc, uint32_t which_reg,
136   uint32_t read, uint32_t write, uint32_t setup)
137{
138	uint32_t v;
139
140	KASSERT(which_reg == PL310_TAG_RAM_CTRL ||
141	    which_reg == PL310_DATA_RAM_CTRL,
142	    ("bad pl310 ram latency register address"));
143
144	v = pl310_read4(sc, which_reg);
145	if (setup != 0) {
146		KASSERT(setup <= 8, ("bad pl310 setup latency: %d", setup));
147		v &= ~RAM_CTRL_SETUP_MASK;
148		v |= (setup - 1) << RAM_CTRL_SETUP_SHIFT;
149	}
150	if (read != 0) {
151		KASSERT(read <= 8, ("bad pl310 read latency: %d", read));
152		v &= ~RAM_CTRL_READ_MASK;
153		v |= (read - 1) << RAM_CTRL_READ_SHIFT;
154	}
155	if (write != 0) {
156		KASSERT(write <= 8, ("bad pl310 write latency: %d", write));
157		v &= ~RAM_CTRL_WRITE_MASK;
158		v |= (write - 1) << RAM_CTRL_WRITE_SHIFT;
159	}
160	pl310_write4(sc, which_reg, v);
161}
162
163static int
164pl310_filter(void *arg)
165{
166	struct pl310_softc *sc = arg;
167	uint32_t intr;
168
169	intr = pl310_read4(sc, PL310_INTR_MASK);
170
171	if (!sc->sc_enabled && (intr & INTR_MASK_ECNTR)) {
172		/*
173		 * This is for debug purpose, so be blunt about it
174		 * We disable PL310 only when something fishy is going
175		 * on and we need to make sure L2 cache is 100% disabled
176		 */
177		panic("pl310: caches disabled but cache event detected\n");
178	}
179
180	return (FILTER_HANDLED);
181}
182
183static __inline void
184pl310_wait_background_op(uint32_t off, uint32_t mask)
185{
186
187	while (pl310_read4(pl310_softc, off) & mask)
188		continue;
189}
190
191
192/**
193 *	pl310_cache_sync - performs a cache sync operation
194 *
195 *	According to the TRM:
196 *
197 *  "Before writing to any other register you must perform an explicit
198 *   Cache Sync operation. This is particularly important when the cache is
199 *   enabled and changes to how the cache allocates new lines are to be made."
200 *
201 *
202 */
203static __inline void
204pl310_cache_sync(void)
205{
206
207	if ((pl310_softc == NULL) || !pl310_softc->sc_enabled)
208		return;
209
210#ifdef PL310_ERRATA_753970
211	if (pl310_softc->sc_rtl_revision == CACHE_ID_RELEASE_r3p0)
212		/* Write uncached PL310 register */
213		pl310_write4(pl310_softc, 0x740, 0xffffffff);
214	else
215#endif
216		pl310_write4(pl310_softc, PL310_CACHE_SYNC, 0xffffffff);
217}
218
219
220static void
221pl310_wbinv_all(void)
222{
223
224	if ((pl310_softc == NULL) || !pl310_softc->sc_enabled)
225		return;
226
227	PL310_LOCK(pl310_softc);
228#ifdef PL310_ERRATA_727915
229	if (pl310_softc->sc_rtl_revision == CACHE_ID_RELEASE_r2p0) {
230		int i, j;
231
232		for (i = 0; i < g_ways_assoc; i++) {
233			for (j = 0; j < g_way_size / g_l2cache_line_size; j++) {
234				pl310_write4(pl310_softc,
235				    PL310_CLEAN_INV_LINE_IDX,
236				    (i << 28 | j << 5));
237			}
238		}
239		pl310_cache_sync();
240		PL310_UNLOCK(pl310_softc);
241		return;
242
243	}
244	if (pl310_softc->sc_rtl_revision == CACHE_ID_RELEASE_r3p0)
245		platform_pl310_write_debug(pl310_softc, 3);
246#endif
247	pl310_write4(pl310_softc, PL310_CLEAN_INV_WAY, g_l2cache_way_mask);
248	pl310_wait_background_op(PL310_CLEAN_INV_WAY, g_l2cache_way_mask);
249	pl310_cache_sync();
250#ifdef PL310_ERRATA_727915
251	if (pl310_softc->sc_rtl_revision == CACHE_ID_RELEASE_r3p0)
252		platform_pl310_write_debug(pl310_softc, 0);
253#endif
254	PL310_UNLOCK(pl310_softc);
255}
256
257static void
258pl310_wbinv_range(vm_paddr_t start, vm_size_t size)
259{
260
261	if ((pl310_softc == NULL) || !pl310_softc->sc_enabled)
262		return;
263
264	PL310_LOCK(pl310_softc);
265	if (start & g_l2cache_align_mask) {
266		size += start & g_l2cache_align_mask;
267		start &= ~g_l2cache_align_mask;
268	}
269	if (size & g_l2cache_align_mask) {
270		size &= ~g_l2cache_align_mask;
271	   	size += g_l2cache_line_size;
272	}
273
274
275#ifdef PL310_ERRATA_727915
276	platform_pl310_write_debug(pl310_softc, 3);
277#endif
278	while (size > 0) {
279#ifdef PL310_ERRATA_588369
280		if (pl310_softc->sc_rtl_revision <= CACHE_ID_RELEASE_r1p0) {
281			/*
282			 * Errata 588369 says that clean + inv may keep the
283			 * cache line if it was clean, the recommanded
284			 * workaround is to clean then invalidate the cache
285			 * line, with write-back and cache linefill disabled.
286			 */
287			pl310_write4(pl310_softc, PL310_CLEAN_LINE_PA, start);
288			pl310_write4(pl310_softc, PL310_INV_LINE_PA, start);
289		} else
290#endif
291			pl310_write4(pl310_softc, PL310_CLEAN_INV_LINE_PA,
292			    start);
293		start += g_l2cache_line_size;
294		size -= g_l2cache_line_size;
295	}
296#ifdef PL310_ERRATA_727915
297	platform_pl310_write_debug(pl310_softc, 0);
298#endif
299
300	pl310_cache_sync();
301	PL310_UNLOCK(pl310_softc);
302}
303
304static void
305pl310_wb_range(vm_paddr_t start, vm_size_t size)
306{
307
308	if ((pl310_softc == NULL) || !pl310_softc->sc_enabled)
309		return;
310
311	PL310_LOCK(pl310_softc);
312	if (start & g_l2cache_align_mask) {
313		size += start & g_l2cache_align_mask;
314		start &= ~g_l2cache_align_mask;
315	}
316
317	if (size & g_l2cache_align_mask) {
318		size &= ~g_l2cache_align_mask;
319		size += g_l2cache_line_size;
320	}
321
322	while (size > 0) {
323		pl310_write4(pl310_softc, PL310_CLEAN_LINE_PA, start);
324		start += g_l2cache_line_size;
325		size -= g_l2cache_line_size;
326	}
327
328	pl310_cache_sync();
329	PL310_UNLOCK(pl310_softc);
330}
331
332static void
333pl310_inv_range(vm_paddr_t start, vm_size_t size)
334{
335
336	if ((pl310_softc == NULL) || !pl310_softc->sc_enabled)
337		return;
338
339	PL310_LOCK(pl310_softc);
340	if (start & g_l2cache_align_mask) {
341		size += start & g_l2cache_align_mask;
342		start &= ~g_l2cache_align_mask;
343	}
344	if (size & g_l2cache_align_mask) {
345		size &= ~g_l2cache_align_mask;
346		size += g_l2cache_line_size;
347	}
348	while (size > 0) {
349		pl310_write4(pl310_softc, PL310_INV_LINE_PA, start);
350		start += g_l2cache_line_size;
351		size -= g_l2cache_line_size;
352	}
353
354	pl310_cache_sync();
355	PL310_UNLOCK(pl310_softc);
356}
357
358static void
359pl310_drain_writebuf(void)
360{
361
362	if ((pl310_softc == NULL) || !pl310_softc->sc_enabled)
363		return;
364
365	PL310_LOCK(pl310_softc);
366	pl310_cache_sync();
367	PL310_UNLOCK(pl310_softc);
368}
369
370static void
371pl310_set_way_sizes(struct pl310_softc *sc)
372{
373	uint32_t aux_value;
374
375	aux_value = pl310_read4(sc, PL310_AUX_CTRL);
376	g_way_size = (aux_value & AUX_CTRL_WAY_SIZE_MASK) >>
377	    AUX_CTRL_WAY_SIZE_SHIFT;
378	g_way_size = 1 << (g_way_size + 13);
379	if (aux_value & (1 << AUX_CTRL_ASSOCIATIVITY_SHIFT))
380		g_ways_assoc = 16;
381	else
382		g_ways_assoc = 8;
383	g_l2cache_way_mask = (1 << g_ways_assoc) - 1;
384	g_l2cache_size = g_way_size * g_ways_assoc;
385}
386
387/*
388 * Setup interrupt handling.  This is done only if the cache controller is
389 * disabled, for debugging.  We set counters so when a cache event happens we'll
390 * get interrupted and be warned that something is wrong, because no cache
391 * events should happen if we're disabled.
392 */
393static void
394pl310_config_intr(void *arg)
395{
396	struct pl310_softc * sc;
397
398	sc = arg;
399
400	/* activate the interrupt */
401	bus_setup_intr(sc->sc_dev, sc->sc_irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
402	    pl310_filter, NULL, sc, &sc->sc_irq_h);
403
404	/* Cache Line Eviction for Counter 0 */
405	pl310_write4(sc, PL310_EVENT_COUNTER0_CONF,
406	    EVENT_COUNTER_CONF_INCR | EVENT_COUNTER_CONF_CO);
407	/* Data Read Request for Counter 1 */
408	pl310_write4(sc, PL310_EVENT_COUNTER1_CONF,
409	    EVENT_COUNTER_CONF_INCR | EVENT_COUNTER_CONF_DRREQ);
410
411	/* Enable and clear pending interrupts */
412	pl310_write4(sc, PL310_INTR_CLEAR, INTR_MASK_ECNTR);
413	pl310_write4(sc, PL310_INTR_MASK, INTR_MASK_ALL);
414
415	/* Enable counters and reset C0 and C1 */
416	pl310_write4(sc, PL310_EVENT_COUNTER_CTRL,
417	    EVENT_COUNTER_CTRL_ENABLED |
418	    EVENT_COUNTER_CTRL_C0_RESET |
419	    EVENT_COUNTER_CTRL_C1_RESET);
420
421	config_intrhook_disestablish(sc->sc_ich);
422	free(sc->sc_ich, M_DEVBUF);
423	sc->sc_ich = NULL;
424}
425
426static int
427pl310_probe(device_t dev)
428{
429
430	if (!ofw_bus_status_okay(dev))
431		return (ENXIO);
432	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
433		return (ENXIO);
434	device_set_desc(dev, "PL310 L2 cache controller");
435	return (0);
436}
437
438static int
439pl310_attach(device_t dev)
440{
441	struct pl310_softc *sc = device_get_softc(dev);
442	int rid;
443	uint32_t cache_id, debug_ctrl;
444
445	sc->sc_dev = dev;
446	rid = 0;
447	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
448	    RF_ACTIVE);
449	if (sc->sc_mem_res == NULL)
450		panic("%s: Cannot map registers", device_get_name(dev));
451
452	/* Allocate an IRQ resource */
453	rid = 0;
454	sc->sc_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
455	                                        RF_ACTIVE | RF_SHAREABLE);
456	if (sc->sc_irq_res == NULL) {
457		device_printf(dev, "cannot allocate IRQ, not using interrupt\n");
458	}
459
460	pl310_softc = sc;
461	mtx_init(&sc->sc_mtx, "pl310lock", NULL, MTX_SPIN);
462
463	cache_id = pl310_read4(sc, PL310_CACHE_ID);
464	sc->sc_rtl_revision = (cache_id >> CACHE_ID_RELEASE_SHIFT) &
465	    CACHE_ID_RELEASE_MASK;
466	device_printf(dev, "Part number: 0x%x, release: 0x%x\n",
467	    (cache_id >> CACHE_ID_PARTNUM_SHIFT) & CACHE_ID_PARTNUM_MASK,
468	    (cache_id >> CACHE_ID_RELEASE_SHIFT) & CACHE_ID_RELEASE_MASK);
469
470	/*
471	 * If L2 cache is already enabled then something has violated the rules,
472	 * because caches are supposed to be off at kernel entry.  The cache
473	 * must be disabled to write the configuration registers without
474	 * triggering an access error (SLVERR), but there's no documented safe
475	 * procedure for disabling the L2 cache in the manual.  So we'll try to
476	 * invent one:
477	 *  - Use the debug register to force write-through mode and prevent
478	 *    linefills (allocation of new lines on read); now anything we do
479	 *    will not cause new data to come into the L2 cache.
480	 *  - Writeback and invalidate the current contents.
481	 *  - Disable the controller.
482	 *  - Restore the original debug settings.
483	 */
484	if (pl310_read4(sc, PL310_CTRL) & CTRL_ENABLED) {
485		device_printf(dev, "Warning: L2 Cache should not already be "
486		    "active; trying to de-activate and re-initialize...\n");
487		sc->sc_enabled = 1;
488		debug_ctrl = pl310_read4(sc, PL310_DEBUG_CTRL);
489		platform_pl310_write_debug(sc, debug_ctrl |
490		    DEBUG_CTRL_DISABLE_WRITEBACK | DEBUG_CTRL_DISABLE_LINEFILL);
491		pl310_set_way_sizes(sc);
492		pl310_wbinv_all();
493		platform_pl310_write_ctrl(sc, CTRL_DISABLED);
494		platform_pl310_write_debug(sc, debug_ctrl);
495	}
496	sc->sc_enabled = pl310_enabled;
497
498	if (sc->sc_enabled) {
499		platform_pl310_init(sc);
500		pl310_set_way_sizes(sc); /* platform init might change these */
501		pl310_write4(pl310_softc, PL310_INV_WAY, 0xffff);
502		pl310_wait_background_op(PL310_INV_WAY, 0xffff);
503		platform_pl310_write_ctrl(sc, CTRL_ENABLED);
504		device_printf(dev, "L2 Cache enabled: %uKB/%dB %d ways\n",
505		    (g_l2cache_size / 1024), g_l2cache_line_size, g_ways_assoc);
506		if (bootverbose)
507			pl310_print_config(sc);
508	} else {
509		if (sc->sc_irq_res != NULL) {
510			sc->sc_ich = malloc(sizeof(*sc->sc_ich), M_DEVBUF, M_WAITOK);
511			sc->sc_ich->ich_func = pl310_config_intr;
512			sc->sc_ich->ich_arg = sc;
513			if (config_intrhook_establish(sc->sc_ich) != 0) {
514				device_printf(dev,
515				    "config_intrhook_establish failed\n");
516				free(sc->sc_ich, M_DEVBUF);
517				return(ENXIO);
518			}
519		}
520
521		device_printf(dev, "L2 Cache disabled\n");
522	}
523
524	/* Set the l2 functions in the set of cpufuncs */
525	cpufuncs.cf_l2cache_wbinv_all = pl310_wbinv_all;
526	cpufuncs.cf_l2cache_wbinv_range = pl310_wbinv_range;
527	cpufuncs.cf_l2cache_inv_range = pl310_inv_range;
528	cpufuncs.cf_l2cache_wb_range = pl310_wb_range;
529	cpufuncs.cf_l2cache_drain_writebuf = pl310_drain_writebuf;
530
531	return (0);
532}
533
534static device_method_t pl310_methods[] = {
535	DEVMETHOD(device_probe, pl310_probe),
536	DEVMETHOD(device_attach, pl310_attach),
537	DEVMETHOD_END
538};
539
540static driver_t pl310_driver = {
541        "l2cache",
542        pl310_methods,
543        sizeof(struct pl310_softc),
544};
545static devclass_t pl310_devclass;
546
547EARLY_DRIVER_MODULE(pl310, simplebus, pl310_driver, pl310_devclass, 0, 0,
548    BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE);
549
550