xref: /freebsd/sys/powerpc/pseries/xics.c (revision 83c0a9e839e2430617ae511cf80e150a8984d414)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright 2011 Nathan Whitehorn
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include "opt_platform.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/module.h>
36 #include <sys/bus.h>
37 #include <sys/conf.h>
38 #include <sys/kernel.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/mutex.h>
42 #include <sys/smp.h>
43 
44 #include <vm/vm.h>
45 #include <vm/pmap.h>
46 
47 #include <machine/bus.h>
48 #include <machine/intr_machdep.h>
49 #include <machine/md_var.h>
50 #include <machine/rtas.h>
51 
52 #include <dev/ofw/ofw_bus.h>
53 #include <dev/ofw/ofw_bus_subr.h>
54 
55 #ifdef POWERNV
56 #include <powerpc/powernv/opal.h>
57 #endif
58 
59 #include "phyp-hvcall.h"
60 #include "pic_if.h"
61 
62 #define XICP_PRIORITY	5	/* Random non-zero number */
63 #define XICP_IPI	2
64 #define MAX_XICP_IRQS	(1<<24)	/* 24-bit XIRR field */
65 
66 static int	xicp_probe(device_t);
67 static int	xicp_attach(device_t);
68 static int	xics_probe(device_t);
69 static int	xics_attach(device_t);
70 
71 static void	xicp_bind(device_t dev, u_int irq, cpuset_t cpumask, void **priv);
72 static void	xicp_dispatch(device_t, struct trapframe *);
73 static void	xicp_enable(device_t, u_int, u_int, void **priv);
74 static void	xicp_eoi(device_t, u_int, void *priv);
75 static void	xicp_ipi(device_t, u_int);
76 static void	xicp_mask(device_t, u_int, void *priv);
77 static void	xicp_unmask(device_t, u_int, void *priv);
78 
79 #ifdef POWERNV
80 extern void (*powernv_smp_ap_extra_init)(void);
81 static void	xicp_smp_cpu_startup(void);
82 #endif
83 
84 static device_method_t  xicp_methods[] = {
85 	/* Device interface */
86 	DEVMETHOD(device_probe,		xicp_probe),
87 	DEVMETHOD(device_attach,	xicp_attach),
88 
89 	/* PIC interface */
90 	DEVMETHOD(pic_bind,		xicp_bind),
91 	DEVMETHOD(pic_dispatch,		xicp_dispatch),
92 	DEVMETHOD(pic_enable,		xicp_enable),
93 	DEVMETHOD(pic_eoi,		xicp_eoi),
94 	DEVMETHOD(pic_ipi,		xicp_ipi),
95 	DEVMETHOD(pic_mask,		xicp_mask),
96 	DEVMETHOD(pic_unmask,		xicp_unmask),
97 
98 	DEVMETHOD_END
99 };
100 
101 static device_method_t  xics_methods[] = {
102 	/* Device interface */
103 	DEVMETHOD(device_probe,		xics_probe),
104 	DEVMETHOD(device_attach,	xics_attach),
105 
106 	DEVMETHOD_END
107 };
108 
109 struct xicp_intvec {
110 	int irq;
111 	int vector;
112 	int cpu;
113 };
114 
115 struct xicp_softc {
116 	struct mtx sc_mtx;
117 	struct resource *mem[MAXCPU];
118 
119 	int cpu_range[2];
120 
121 	int ibm_int_on;
122 	int ibm_int_off;
123 	int ibm_get_xive;
124 	int ibm_set_xive;
125 
126 	/* XXX: inefficient -- hash table? tree? */
127 	struct xicp_intvec intvecs[256];
128 	int nintvecs;
129 	int ipi_vec;
130 	bool xics_emu;
131 };
132 
133 static driver_t xicp_driver = {
134 	"xicp",
135 	xicp_methods,
136 	sizeof(struct xicp_softc)
137 };
138 
139 static driver_t xics_driver = {
140 	"xics",
141 	xics_methods,
142 	0
143 };
144 
145 #ifdef POWERNV
146 /* We can only pass physical addresses into OPAL.  Kernel stacks are in the KVA,
147  * not in the direct map, so we need to somehow extract the physical address.
148  * However, pmap_kextract() takes locks, which is forbidden in a critical region
149  * (which PIC_DISPATCH() operates in).  The kernel is mapped into the Direct
150  * Map (0xc000....), and the CPU implicitly drops the top two bits when doing
151  * real address by nature that the bus width is smaller than 64-bits.  Placing
152  * cpu_xirr into the DMAP lets us take advantage of this and avoids the
153  * pmap_kextract() that would otherwise be needed if using the stack variable.
154  */
155 static uint32_t cpu_xirr[MAXCPU];
156 #endif
157 
158 static devclass_t xicp_devclass;
159 static devclass_t xics_devclass;
160 
161 EARLY_DRIVER_MODULE(xicp, ofwbus, xicp_driver, xicp_devclass, 0, 0,
162     BUS_PASS_INTERRUPT-1);
163 EARLY_DRIVER_MODULE(xics, ofwbus, xics_driver, xics_devclass, 0, 0,
164     BUS_PASS_INTERRUPT);
165 
166 #ifdef POWERNV
167 static struct resource *
168 xicp_mem_for_cpu(int cpu)
169 {
170 	devclass_t dc;
171 	device_t dev;
172 	struct xicp_softc *sc;
173 	int i;
174 
175 	dc = devclass_find(xicp_driver.name);
176 	for (i = 0; (dev = devclass_get_device(dc, i)) != NULL; i++){
177 		sc = device_get_softc(dev);
178 		if (cpu >= sc->cpu_range[0] && cpu < sc->cpu_range[1])
179 			return (sc->mem[cpu - sc->cpu_range[0]]);
180 	}
181 
182 	return (NULL);
183 }
184 #endif
185 
186 static int
187 xicp_probe(device_t dev)
188 {
189 
190 	if (!ofw_bus_is_compatible(dev, "ibm,ppc-xicp") &&
191 	    !ofw_bus_is_compatible(dev, "ibm,opal-intc"))
192 		return (ENXIO);
193 
194 	device_set_desc(dev, "External Interrupt Presentation Controller");
195 	return (BUS_PROBE_GENERIC);
196 }
197 
198 static int
199 xics_probe(device_t dev)
200 {
201 
202 	if (!ofw_bus_is_compatible(dev, "ibm,ppc-xics") &&
203 	    !ofw_bus_is_compatible(dev, "IBM,opal-xics"))
204 		return (ENXIO);
205 
206 	device_set_desc(dev, "External Interrupt Source Controller");
207 	return (BUS_PROBE_GENERIC);
208 }
209 
210 static int
211 xicp_attach(device_t dev)
212 {
213 	struct xicp_softc *sc = device_get_softc(dev);
214 	phandle_t phandle = ofw_bus_get_node(dev);
215 
216 	if (rtas_exists()) {
217 		sc->ibm_int_on = rtas_token_lookup("ibm,int-on");
218 		sc->ibm_int_off = rtas_token_lookup("ibm,int-off");
219 		sc->ibm_set_xive = rtas_token_lookup("ibm,set-xive");
220 		sc->ibm_get_xive = rtas_token_lookup("ibm,get-xive");
221 #ifdef POWERNV
222 	} else if (opal_check() == 0) {
223 		/* No init needed */
224 #endif
225 	} else {
226 		device_printf(dev, "Cannot attach without RTAS or OPAL\n");
227 		return (ENXIO);
228 	}
229 
230 	if (OF_hasprop(phandle, "ibm,interrupt-server-ranges")) {
231 		OF_getencprop(phandle, "ibm,interrupt-server-ranges",
232 		    sc->cpu_range, sizeof(sc->cpu_range));
233 		sc->cpu_range[1] += sc->cpu_range[0];
234 		device_printf(dev, "Handling CPUs %d-%d\n", sc->cpu_range[0],
235 		    sc->cpu_range[1]-1);
236 #ifdef POWERNV
237 	} else if (ofw_bus_is_compatible(dev, "ibm,opal-intc")) {
238 			/*
239 			 * For now run POWER9 XIVE interrupt controller in XICS
240 			 * compatibility mode.
241 			 */
242 			sc->xics_emu = true;
243 			opal_call(OPAL_XIVE_RESET, OPAL_XIVE_XICS_MODE_EMU);
244 #endif
245 	} else {
246 		sc->cpu_range[0] = 0;
247 		sc->cpu_range[1] = mp_ncpus;
248 	}
249 
250 #ifdef POWERNV
251 	if (mfmsr() & PSL_HV) {
252 		int i;
253 
254 		if (sc->xics_emu) {
255 			opal_call(OPAL_INT_SET_CPPR, 0xff);
256 			for (i = 0; i < mp_ncpus; i++) {
257 				opal_call(OPAL_INT_SET_MFRR,
258 				    pcpu_find(i)->pc_hwref, 0xff);
259 			}
260 		} else {
261 			for (i = 0; i < sc->cpu_range[1] - sc->cpu_range[0]; i++) {
262 				sc->mem[i] = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
263 				    &i, RF_ACTIVE);
264 				if (sc->mem[i] == NULL) {
265 					device_printf(dev, "Could not alloc mem "
266 					    "resource %d\n", i);
267 					return (ENXIO);
268 				}
269 
270 				/* Unmask interrupts on all cores */
271 				bus_write_1(sc->mem[i], 4, 0xff);
272 				bus_write_1(sc->mem[i], 12, 0xff);
273 			}
274 		}
275 	}
276 #endif
277 
278 	mtx_init(&sc->sc_mtx, "XICP", NULL, MTX_DEF);
279 	sc->nintvecs = 0;
280 
281 	powerpc_register_pic(dev, OF_xref_from_node(phandle), MAX_XICP_IRQS,
282 	    1 /* Number of IPIs */, FALSE);
283 	root_pic = dev;
284 
285 #ifdef POWERNV
286 	if (sc->xics_emu)
287 		powernv_smp_ap_extra_init = xicp_smp_cpu_startup;
288 #endif
289 
290 	return (0);
291 }
292 
293 static int
294 xics_attach(device_t dev)
295 {
296 	phandle_t phandle = ofw_bus_get_node(dev);
297 
298 	/* The XICP (root PIC) will handle all our interrupts */
299 	powerpc_register_pic(root_pic, OF_xref_from_node(phandle),
300 	    MAX_XICP_IRQS, 1 /* Number of IPIs */, FALSE);
301 
302 	return (0);
303 }
304 
305 static __inline struct xicp_intvec *
306 xicp_setup_priv(struct xicp_softc *sc, u_int irq, void **priv)
307 {
308 	if (*priv == NULL) {
309 		KASSERT(sc->nintvecs + 1 < nitems(sc->intvecs),
310 			("Too many XICP interrupts"));
311 		mtx_lock(&sc->sc_mtx);
312 		*priv = &sc->intvecs[sc->nintvecs++];
313 		mtx_unlock(&sc->sc_mtx);
314 	}
315 
316 	return (*priv);
317 }
318 
319 /*
320  * PIC I/F methods.
321  */
322 
323 static void
324 xicp_bind(device_t dev, u_int irq, cpuset_t cpumask, void **priv)
325 {
326 	struct xicp_softc *sc = device_get_softc(dev);
327 	struct xicp_intvec *iv;
328 	cell_t status, cpu;
329 	int ncpus, i, error = -1;
330 
331 	/* Ignore IPIs */
332 	if (irq == MAX_XICP_IRQS)
333 		return;
334 
335 	iv = xicp_setup_priv(sc, irq, priv);
336 
337 	/*
338 	 * This doesn't appear to actually support affinity groups, so pick a
339 	 * random CPU.
340 	 */
341 	ncpus = 0;
342 	CPU_FOREACH(cpu)
343 		if (CPU_ISSET(cpu, &cpumask)) ncpus++;
344 
345 	i = mftb() % ncpus;
346 	ncpus = 0;
347 	CPU_FOREACH(cpu) {
348 		if (!CPU_ISSET(cpu, &cpumask))
349 			continue;
350 		if (ncpus == i)
351 			break;
352 		ncpus++;
353 	}
354 
355 	cpu = pcpu_find(cpu)->pc_hwref;
356 	iv->cpu = cpu;
357 
358 	if (rtas_exists())
359 		error = rtas_call_method(sc->ibm_set_xive, 3, 1, irq, cpu,
360 		    XICP_PRIORITY, &status);
361 #ifdef POWERNV
362 	else
363 		error = opal_call(OPAL_SET_XIVE, irq, cpu << 2, XICP_PRIORITY);
364 #endif
365 
366 	if (error < 0)
367 		panic("Cannot bind interrupt %d to CPU %d", irq, cpu);
368 }
369 
370 static void
371 xicp_dispatch(device_t dev, struct trapframe *tf)
372 {
373 	struct xicp_softc *sc;
374 	struct resource *regs = NULL;
375 	uint64_t xirr, junk;
376 	int i;
377 
378 	sc = device_get_softc(dev);
379 #ifdef POWERNV
380 	if ((mfmsr() & PSL_HV) && !sc->xics_emu) {
381 		regs = xicp_mem_for_cpu(PCPU_GET(hwref));
382 		KASSERT(regs != NULL,
383 		    ("Can't find regs for CPU %ld", (uintptr_t)PCPU_GET(hwref)));
384 	}
385 #endif
386 
387 	for (;;) {
388 		/* Return value in R4, use the PFT call */
389 		if (regs) {
390 			xirr = bus_read_4(regs, 4);
391 #ifdef POWERNV
392 		} else if (sc->xics_emu) {
393 			opal_call(OPAL_INT_GET_XIRR, &cpu_xirr[PCPU_GET(cpuid)],
394 			    false);
395 			xirr = cpu_xirr[PCPU_GET(cpuid)];
396 #endif
397 		} else {
398 			/* Return value in R4, use the PFT call */
399 			phyp_pft_hcall(H_XIRR, 0, 0, 0, 0, &xirr, &junk, &junk);
400 		}
401 		xirr &= 0x00ffffff;
402 
403 		if (xirr == 0) /* No more pending interrupts? */
404 			break;
405 
406 		if (xirr == XICP_IPI) {		/* Magic number for IPIs */
407 			xirr = MAX_XICP_IRQS;	/* Map to FreeBSD magic */
408 
409 			/* Clear IPI */
410 			if (regs)
411 				bus_write_1(regs, 12, 0xff);
412 #ifdef POWERNV
413 			else if (sc->xics_emu)
414 				opal_call(OPAL_INT_SET_MFRR,
415 				    PCPU_GET(hwref), 0xff);
416 #endif
417 			else
418 				phyp_hcall(H_IPI, (uint64_t)(PCPU_GET(hwref)),
419 				    0xff);
420 			i = sc->ipi_vec;
421 		} else {
422 			/* XXX: super inefficient */
423 			for (i = 0; i < sc->nintvecs; i++) {
424 				if (sc->intvecs[i].irq == xirr)
425 					break;
426 			}
427 			KASSERT(i < sc->nintvecs, ("Unmapped XIRR"));
428 		}
429 
430 		powerpc_dispatch_intr(sc->intvecs[i].vector, tf);
431 	}
432 }
433 
434 static void
435 xicp_enable(device_t dev, u_int irq, u_int vector, void **priv)
436 {
437 	struct xicp_softc *sc;
438 	struct xicp_intvec *intr;
439 	cell_t status, cpu;
440 
441 	sc = device_get_softc(dev);
442 
443 	/* Bind to this CPU to start: distrib. ID is last entry in gserver# */
444 	cpu = PCPU_GET(hwref);
445 
446 	intr = xicp_setup_priv(sc, irq, priv);
447 
448 	intr->irq = irq;
449 	intr->vector = vector;
450 	intr->cpu = cpu;
451 	mb();
452 
453 	/* IPIs are also enabled.  Stash off the vector index */
454 	if (irq == MAX_XICP_IRQS) {
455 		sc->ipi_vec = intr - sc->intvecs;
456 		return;
457 	}
458 
459 	if (rtas_exists()) {
460 		rtas_call_method(sc->ibm_set_xive, 3, 1, irq, cpu,
461 		    XICP_PRIORITY, &status);
462 		xicp_unmask(dev, irq, intr);
463 #ifdef POWERNV
464 	} else {
465 		status = opal_call(OPAL_SET_XIVE, irq, cpu << 2, XICP_PRIORITY);
466 		/* Unmask implicit for OPAL */
467 
468 		if (status != 0)
469 			panic("OPAL_SET_XIVE IRQ %d -> cpu %d failed: %d", irq,
470 			    cpu, status);
471 #endif
472 	}
473 }
474 
475 static void
476 xicp_eoi(device_t dev, u_int irq, void *priv)
477 {
478 #ifdef POWERNV
479 	struct xicp_softc *sc;
480 #endif
481 	uint64_t xirr;
482 
483 	if (irq == MAX_XICP_IRQS) /* Remap IPI interrupt to internal value */
484 		irq = XICP_IPI;
485 	xirr = irq | (0xff << 24);
486 
487 #ifdef POWERNV
488 	if (mfmsr() & PSL_HV) {
489 		sc = device_get_softc(dev);
490 		if (sc->xics_emu)
491 			opal_call(OPAL_INT_EOI, xirr);
492 		else
493 			bus_write_4(xicp_mem_for_cpu(PCPU_GET(hwref)), 4, xirr);
494 	} else
495 #endif
496 		phyp_hcall(H_EOI, xirr);
497 }
498 
499 static void
500 xicp_ipi(device_t dev, u_int cpu)
501 {
502 
503 #ifdef POWERNV
504 	struct xicp_softc *sc;
505 	cpu = pcpu_find(cpu)->pc_hwref;
506 
507 	if (mfmsr() & PSL_HV) {
508 		sc = device_get_softc(dev);
509 		if (sc->xics_emu) {
510 			int64_t rv;
511 			rv = opal_call(OPAL_INT_SET_MFRR, cpu, XICP_PRIORITY);
512 			if (rv != 0)
513 			    device_printf(dev, "IPI SET_MFRR result: %ld\n", rv);
514 		} else
515 			bus_write_1(xicp_mem_for_cpu(cpu), 12, XICP_PRIORITY);
516 	} else
517 #endif
518 		phyp_hcall(H_IPI, (uint64_t)cpu, XICP_PRIORITY);
519 }
520 
521 static void
522 xicp_mask(device_t dev, u_int irq, void *priv)
523 {
524 	struct xicp_softc *sc = device_get_softc(dev);
525 	cell_t status;
526 
527 	if (irq == MAX_XICP_IRQS)
528 		return;
529 
530 	if (rtas_exists()) {
531 		rtas_call_method(sc->ibm_int_off, 1, 1, irq, &status);
532 #ifdef POWERNV
533 	} else {
534 		struct xicp_intvec *ivec = priv;
535 
536 		KASSERT(ivec != NULL, ("Masking unconfigured interrupt"));
537 		opal_call(OPAL_SET_XIVE, irq, ivec->cpu << 2, 0xff);
538 #endif
539 	}
540 }
541 
542 static void
543 xicp_unmask(device_t dev, u_int irq, void *priv)
544 {
545 	struct xicp_softc *sc = device_get_softc(dev);
546 	cell_t status;
547 
548 	if (irq == MAX_XICP_IRQS)
549 		return;
550 
551 	if (rtas_exists()) {
552 		rtas_call_method(sc->ibm_int_on, 1, 1, irq, &status);
553 #ifdef POWERNV
554 	} else {
555 		struct xicp_intvec *ivec = priv;
556 
557 		KASSERT(ivec != NULL, ("Unmasking unconfigured interrupt"));
558 		opal_call(OPAL_SET_XIVE, irq, ivec->cpu << 2, XICP_PRIORITY);
559 #endif
560 	}
561 }
562 
563 #ifdef POWERNV
564 /* This is only used on POWER9 systems with the XIVE's XICS emulation. */
565 static void
566 xicp_smp_cpu_startup(void)
567 {
568 	struct xicp_softc *sc;
569 
570 	if (mfmsr() & PSL_HV) {
571 		sc = device_get_softc(root_pic);
572 
573 		if (sc->xics_emu)
574 			opal_call(OPAL_INT_SET_CPPR, 0xff);
575 	}
576 }
577 #endif
578