1 /*
2  * pSeries_lpar.c
3  * Copyright (C) 2001 Todd Inglett, IBM Corporation
4  *
5  * pSeries LPAR support.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  */
21 
22 #undef DEBUG_LOW
23 
24 #include <linux/kernel.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/console.h>
27 #include <asm/processor.h>
28 #include <asm/mmu.h>
29 #include <asm/page.h>
30 #include <asm/pgtable.h>
31 #include <asm/machdep.h>
32 #include <asm/abs_addr.h>
33 #include <asm/mmu_context.h>
34 #include <asm/iommu.h>
35 #include <asm/tlbflush.h>
36 #include <asm/tlb.h>
37 #include <asm/prom.h>
38 #include <asm/cputable.h>
39 #include <asm/udbg.h>
40 #include <asm/smp.h>
41 
42 #include "plpar_wrappers.h"
43 
44 #ifdef DEBUG_LOW
45 #define DBG_LOW(fmt...) do { udbg_printf(fmt); } while(0)
46 #else
47 #define DBG_LOW(fmt...) do { } while(0)
48 #endif
49 
50 /* in hvCall.S */
51 EXPORT_SYMBOL(plpar_hcall);
52 EXPORT_SYMBOL(plpar_hcall9);
53 EXPORT_SYMBOL(plpar_hcall_norets);
54 
55 extern void pSeries_find_serial_port(void);
56 
57 
58 int vtermno;	/* virtual terminal# for udbg  */
59 
60 #define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
61 static void udbg_hvsi_putc(char c)
62 {
63 	/* packet's seqno isn't used anyways */
64 	uint8_t packet[] __ALIGNED__ = { 0xff, 5, 0, 0, c };
65 	int rc;
66 
67 	if (c == '\n')
68 		udbg_hvsi_putc('\r');
69 
70 	do {
71 		rc = plpar_put_term_char(vtermno, sizeof(packet), packet);
72 	} while (rc == H_BUSY);
73 }
74 
75 static long hvsi_udbg_buf_len;
76 static uint8_t hvsi_udbg_buf[256];
77 
78 static int udbg_hvsi_getc_poll(void)
79 {
80 	unsigned char ch;
81 	int rc, i;
82 
83 	if (hvsi_udbg_buf_len == 0) {
84 		rc = plpar_get_term_char(vtermno, &hvsi_udbg_buf_len, hvsi_udbg_buf);
85 		if (rc != H_SUCCESS || hvsi_udbg_buf[0] != 0xff) {
86 			/* bad read or non-data packet */
87 			hvsi_udbg_buf_len = 0;
88 		} else {
89 			/* remove the packet header */
90 			for (i = 4; i < hvsi_udbg_buf_len; i++)
91 				hvsi_udbg_buf[i-4] = hvsi_udbg_buf[i];
92 			hvsi_udbg_buf_len -= 4;
93 		}
94 	}
95 
96 	if (hvsi_udbg_buf_len <= 0 || hvsi_udbg_buf_len > 256) {
97 		/* no data ready */
98 		hvsi_udbg_buf_len = 0;
99 		return -1;
100 	}
101 
102 	ch = hvsi_udbg_buf[0];
103 	/* shift remaining data down */
104 	for (i = 1; i < hvsi_udbg_buf_len; i++) {
105 		hvsi_udbg_buf[i-1] = hvsi_udbg_buf[i];
106 	}
107 	hvsi_udbg_buf_len--;
108 
109 	return ch;
110 }
111 
112 static int udbg_hvsi_getc(void)
113 {
114 	int ch;
115 	for (;;) {
116 		ch = udbg_hvsi_getc_poll();
117 		if (ch == -1) {
118 			/* This shouldn't be needed...but... */
119 			volatile unsigned long delay;
120 			for (delay=0; delay < 2000000; delay++)
121 				;
122 		} else {
123 			return ch;
124 		}
125 	}
126 }
127 
128 static void udbg_putcLP(char c)
129 {
130 	char buf[16];
131 	unsigned long rc;
132 
133 	if (c == '\n')
134 		udbg_putcLP('\r');
135 
136 	buf[0] = c;
137 	do {
138 		rc = plpar_put_term_char(vtermno, 1, buf);
139 	} while(rc == H_BUSY);
140 }
141 
142 /* Buffered chars getc */
143 static long inbuflen;
144 static long inbuf[2];	/* must be 2 longs */
145 
146 static int udbg_getc_pollLP(void)
147 {
148 	/* The interface is tricky because it may return up to 16 chars.
149 	 * We save them statically for future calls to udbg_getc().
150 	 */
151 	char ch, *buf = (char *)inbuf;
152 	int i;
153 	long rc;
154 	if (inbuflen == 0) {
155 		/* get some more chars. */
156 		inbuflen = 0;
157 		rc = plpar_get_term_char(vtermno, &inbuflen, buf);
158 		if (rc != H_SUCCESS)
159 			inbuflen = 0;	/* otherwise inbuflen is garbage */
160 	}
161 	if (inbuflen <= 0 || inbuflen > 16) {
162 		/* Catch error case as well as other oddities (corruption) */
163 		inbuflen = 0;
164 		return -1;
165 	}
166 	ch = buf[0];
167 	for (i = 1; i < inbuflen; i++)	/* shuffle them down. */
168 		buf[i-1] = buf[i];
169 	inbuflen--;
170 	return ch;
171 }
172 
173 static int udbg_getcLP(void)
174 {
175 	int ch;
176 	for (;;) {
177 		ch = udbg_getc_pollLP();
178 		if (ch == -1) {
179 			/* This shouldn't be needed...but... */
180 			volatile unsigned long delay;
181 			for (delay=0; delay < 2000000; delay++)
182 				;
183 		} else {
184 			return ch;
185 		}
186 	}
187 }
188 
189 /* call this from early_init() for a working debug console on
190  * vterm capable LPAR machines
191  */
192 void __init udbg_init_debug_lpar(void)
193 {
194 	vtermno = 0;
195 	udbg_putc = udbg_putcLP;
196 	udbg_getc = udbg_getcLP;
197 	udbg_getc_poll = udbg_getc_pollLP;
198 }
199 
200 /* returns 0 if couldn't find or use /chosen/stdout as console */
201 void __init find_udbg_vterm(void)
202 {
203 	struct device_node *stdout_node;
204 	const u32 *termno;
205 	const char *name;
206 	int add_console;
207 
208 	/* find the boot console from /chosen/stdout */
209 	if (!of_chosen)
210 		return;
211 	name = of_get_property(of_chosen, "linux,stdout-path", NULL);
212 	if (name == NULL)
213 		return;
214 	stdout_node = of_find_node_by_path(name);
215 	if (!stdout_node)
216 		return;
217 	name = of_get_property(stdout_node, "name", NULL);
218 	if (!name) {
219 		printk(KERN_WARNING "stdout node missing 'name' property!\n");
220 		goto out;
221 	}
222 	/* The user has requested a console so this is already set up. */
223 	add_console = !strstr(cmd_line, "console=");
224 
225 	/* Check if it's a virtual terminal */
226 	if (strncmp(name, "vty", 3) != 0)
227 		goto out;
228 	termno = of_get_property(stdout_node, "reg", NULL);
229 	if (termno == NULL)
230 		goto out;
231 	vtermno = termno[0];
232 
233 	if (of_device_is_compatible(stdout_node, "hvterm1")) {
234 		udbg_putc = udbg_putcLP;
235 		udbg_getc = udbg_getcLP;
236 		udbg_getc_poll = udbg_getc_pollLP;
237 		if (add_console)
238 			add_preferred_console("hvc", termno[0] & 0xff, NULL);
239 	} else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) {
240 		vtermno = termno[0];
241 		udbg_putc = udbg_hvsi_putc;
242 		udbg_getc = udbg_hvsi_getc;
243 		udbg_getc_poll = udbg_hvsi_getc_poll;
244 		if (add_console)
245 			add_preferred_console("hvsi", termno[0] & 0xff, NULL);
246 	}
247 out:
248 	of_node_put(stdout_node);
249 }
250 
251 void vpa_init(int cpu)
252 {
253 	int hwcpu = get_hard_smp_processor_id(cpu);
254 	unsigned long addr;
255 	long ret;
256 
257 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
258 		lppaca[cpu].vmxregs_in_use = 1;
259 
260 	addr = __pa(&lppaca[cpu]);
261 	ret = register_vpa(hwcpu, addr);
262 
263 	if (ret) {
264 		printk(KERN_ERR "WARNING: vpa_init: VPA registration for "
265 				"cpu %d (hw %d) of area %lx returns %ld\n",
266 				cpu, hwcpu, addr, ret);
267 		return;
268 	}
269 	/*
270 	 * PAPR says this feature is SLB-Buffer but firmware never
271 	 * reports that.  All SPLPAR support SLB shadow buffer.
272 	 */
273 	addr = __pa(&slb_shadow[cpu]);
274 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
275 		ret = register_slb_shadow(hwcpu, addr);
276 		if (ret)
277 			printk(KERN_ERR
278 			       "WARNING: vpa_init: SLB shadow buffer "
279 			       "registration for cpu %d (hw %d) of area %lx "
280 			       "returns %ld\n", cpu, hwcpu, addr, ret);
281 	}
282 }
283 
284 static long pSeries_lpar_hpte_insert(unsigned long hpte_group,
285  			      unsigned long va, unsigned long pa,
286  			      unsigned long rflags, unsigned long vflags,
287 			      int psize, int ssize)
288 {
289 	unsigned long lpar_rc;
290 	unsigned long flags;
291 	unsigned long slot;
292 	unsigned long hpte_v, hpte_r;
293 
294 	if (!(vflags & HPTE_V_BOLTED))
295 		DBG_LOW("hpte_insert(group=%lx, va=%016lx, pa=%016lx, "
296 			"rflags=%lx, vflags=%lx, psize=%d)\n",
297 		hpte_group, va, pa, rflags, vflags, psize);
298 
299 	hpte_v = hpte_encode_v(va, psize, ssize) | vflags | HPTE_V_VALID;
300 	hpte_r = hpte_encode_r(pa, psize) | rflags;
301 
302 	if (!(vflags & HPTE_V_BOLTED))
303 		DBG_LOW(" hpte_v=%016lx, hpte_r=%016lx\n", hpte_v, hpte_r);
304 
305 	/* Now fill in the actual HPTE */
306 	/* Set CEC cookie to 0         */
307 	/* Zero page = 0               */
308 	/* I-cache Invalidate = 0      */
309 	/* I-cache synchronize = 0     */
310 	/* Exact = 0                   */
311 	flags = 0;
312 
313 	/* Make pHyp happy */
314 	if (rflags & (_PAGE_GUARDED|_PAGE_NO_CACHE))
315 		hpte_r &= ~_PAGE_COHERENT;
316 
317 	lpar_rc = plpar_pte_enter(flags, hpte_group, hpte_v, hpte_r, &slot);
318 	if (unlikely(lpar_rc == H_PTEG_FULL)) {
319 		if (!(vflags & HPTE_V_BOLTED))
320 			DBG_LOW(" full\n");
321 		return -1;
322 	}
323 
324 	/*
325 	 * Since we try and ioremap PHBs we don't own, the pte insert
326 	 * will fail. However we must catch the failure in hash_page
327 	 * or we will loop forever, so return -2 in this case.
328 	 */
329 	if (unlikely(lpar_rc != H_SUCCESS)) {
330 		if (!(vflags & HPTE_V_BOLTED))
331 			DBG_LOW(" lpar err %d\n", lpar_rc);
332 		return -2;
333 	}
334 	if (!(vflags & HPTE_V_BOLTED))
335 		DBG_LOW(" -> slot: %d\n", slot & 7);
336 
337 	/* Because of iSeries, we have to pass down the secondary
338 	 * bucket bit here as well
339 	 */
340 	return (slot & 7) | (!!(vflags & HPTE_V_SECONDARY) << 3);
341 }
342 
343 static DEFINE_SPINLOCK(pSeries_lpar_tlbie_lock);
344 
345 static long pSeries_lpar_hpte_remove(unsigned long hpte_group)
346 {
347 	unsigned long slot_offset;
348 	unsigned long lpar_rc;
349 	int i;
350 	unsigned long dummy1, dummy2;
351 
352 	/* pick a random slot to start at */
353 	slot_offset = mftb() & 0x7;
354 
355 	for (i = 0; i < HPTES_PER_GROUP; i++) {
356 
357 		/* don't remove a bolted entry */
358 		lpar_rc = plpar_pte_remove(H_ANDCOND, hpte_group + slot_offset,
359 					   (0x1UL << 4), &dummy1, &dummy2);
360 		if (lpar_rc == H_SUCCESS)
361 			return i;
362 		BUG_ON(lpar_rc != H_NOT_FOUND);
363 
364 		slot_offset++;
365 		slot_offset &= 0x7;
366 	}
367 
368 	return -1;
369 }
370 
371 static void pSeries_lpar_hptab_clear(void)
372 {
373 	unsigned long size_bytes = 1UL << ppc64_pft_size;
374 	unsigned long hpte_count = size_bytes >> 4;
375 	unsigned long dummy1, dummy2, dword0;
376 	long lpar_rc;
377 	int i;
378 
379 	/* TODO: Use bulk call */
380 	for (i = 0; i < hpte_count; i++) {
381 		/* dont remove HPTEs with VRMA mappings */
382 		lpar_rc = plpar_pte_remove_raw(H_ANDCOND, i, HPTE_V_1TB_SEG,
383 						&dummy1, &dummy2);
384 		if (lpar_rc == H_NOT_FOUND) {
385 			lpar_rc = plpar_pte_read_raw(0, i, &dword0, &dummy1);
386 			if (!lpar_rc && ((dword0 & HPTE_V_VRMA_MASK)
387 				!= HPTE_V_VRMA_MASK))
388 				/* Can be hpte for 1TB Seg. So remove it */
389 				plpar_pte_remove_raw(0, i, 0, &dummy1, &dummy2);
390 		}
391 	}
392 }
393 
394 /*
395  * This computes the AVPN and B fields of the first dword of a HPTE,
396  * for use when we want to match an existing PTE.  The bottom 7 bits
397  * of the returned value are zero.
398  */
399 static inline unsigned long hpte_encode_avpn(unsigned long va, int psize,
400 					     int ssize)
401 {
402 	unsigned long v;
403 
404 	v = (va >> 23) & ~(mmu_psize_defs[psize].avpnm);
405 	v <<= HPTE_V_AVPN_SHIFT;
406 	v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT;
407 	return v;
408 }
409 
410 /*
411  * NOTE: for updatepp ops we are fortunate that the linux "newpp" bits and
412  * the low 3 bits of flags happen to line up.  So no transform is needed.
413  * We can probably optimize here and assume the high bits of newpp are
414  * already zero.  For now I am paranoid.
415  */
416 static long pSeries_lpar_hpte_updatepp(unsigned long slot,
417 				       unsigned long newpp,
418 				       unsigned long va,
419 				       int psize, int ssize, int local)
420 {
421 	unsigned long lpar_rc;
422 	unsigned long flags = (newpp & 7) | H_AVPN;
423 	unsigned long want_v;
424 
425 	want_v = hpte_encode_avpn(va, psize, ssize);
426 
427 	DBG_LOW("    update: avpnv=%016lx, hash=%016lx, f=%x, psize: %d ... ",
428 		want_v, slot, flags, psize);
429 
430 	lpar_rc = plpar_pte_protect(flags, slot, want_v);
431 
432 	if (lpar_rc == H_NOT_FOUND) {
433 		DBG_LOW("not found !\n");
434 		return -1;
435 	}
436 
437 	DBG_LOW("ok\n");
438 
439 	BUG_ON(lpar_rc != H_SUCCESS);
440 
441 	return 0;
442 }
443 
444 static unsigned long pSeries_lpar_hpte_getword0(unsigned long slot)
445 {
446 	unsigned long dword0;
447 	unsigned long lpar_rc;
448 	unsigned long dummy_word1;
449 	unsigned long flags;
450 
451 	/* Read 1 pte at a time                        */
452 	/* Do not need RPN to logical page translation */
453 	/* No cross CEC PFT access                     */
454 	flags = 0;
455 
456 	lpar_rc = plpar_pte_read(flags, slot, &dword0, &dummy_word1);
457 
458 	BUG_ON(lpar_rc != H_SUCCESS);
459 
460 	return dword0;
461 }
462 
463 static long pSeries_lpar_hpte_find(unsigned long va, int psize, int ssize)
464 {
465 	unsigned long hash;
466 	unsigned long i;
467 	long slot;
468 	unsigned long want_v, hpte_v;
469 
470 	hash = hpt_hash(va, mmu_psize_defs[psize].shift, ssize);
471 	want_v = hpte_encode_avpn(va, psize, ssize);
472 
473 	/* Bolted entries are always in the primary group */
474 	slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
475 	for (i = 0; i < HPTES_PER_GROUP; i++) {
476 		hpte_v = pSeries_lpar_hpte_getword0(slot);
477 
478 		if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))
479 			/* HPTE matches */
480 			return slot;
481 		++slot;
482 	}
483 
484 	return -1;
485 }
486 
487 static void pSeries_lpar_hpte_updateboltedpp(unsigned long newpp,
488 					     unsigned long ea,
489 					     int psize, int ssize)
490 {
491 	unsigned long lpar_rc, slot, vsid, va, flags;
492 
493 	vsid = get_kernel_vsid(ea, ssize);
494 	va = hpt_va(ea, vsid, ssize);
495 
496 	slot = pSeries_lpar_hpte_find(va, psize, ssize);
497 	BUG_ON(slot == -1);
498 
499 	flags = newpp & 7;
500 	lpar_rc = plpar_pte_protect(flags, slot, 0);
501 
502 	BUG_ON(lpar_rc != H_SUCCESS);
503 }
504 
505 static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long va,
506 					 int psize, int ssize, int local)
507 {
508 	unsigned long want_v;
509 	unsigned long lpar_rc;
510 	unsigned long dummy1, dummy2;
511 
512 	DBG_LOW("    inval : slot=%lx, va=%016lx, psize: %d, local: %d",
513 		slot, va, psize, local);
514 
515 	want_v = hpte_encode_avpn(va, psize, ssize);
516 	lpar_rc = plpar_pte_remove(H_AVPN, slot, want_v, &dummy1, &dummy2);
517 	if (lpar_rc == H_NOT_FOUND)
518 		return;
519 
520 	BUG_ON(lpar_rc != H_SUCCESS);
521 }
522 
523 /* Flag bits for H_BULK_REMOVE */
524 #define HBR_REQUEST	0x4000000000000000UL
525 #define HBR_RESPONSE	0x8000000000000000UL
526 #define HBR_END		0xc000000000000000UL
527 #define HBR_AVPN	0x0200000000000000UL
528 #define HBR_ANDCOND	0x0100000000000000UL
529 
530 /*
531  * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie
532  * lock.
533  */
534 static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
535 {
536 	unsigned long i, pix, rc;
537 	unsigned long flags = 0;
538 	struct ppc64_tlb_batch *batch = &__get_cpu_var(ppc64_tlb_batch);
539 	int lock_tlbie = !cpu_has_feature(CPU_FTR_LOCKLESS_TLBIE);
540 	unsigned long param[9];
541 	unsigned long va;
542 	unsigned long hash, index, shift, hidx, slot;
543 	real_pte_t pte;
544 	int psize, ssize;
545 
546 	if (lock_tlbie)
547 		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
548 
549 	psize = batch->psize;
550 	ssize = batch->ssize;
551 	pix = 0;
552 	for (i = 0; i < number; i++) {
553 		va = batch->vaddr[i];
554 		pte = batch->pte[i];
555 		pte_iterate_hashed_subpages(pte, psize, va, index, shift) {
556 			hash = hpt_hash(va, shift, ssize);
557 			hidx = __rpte_to_hidx(pte, index);
558 			if (hidx & _PTEIDX_SECONDARY)
559 				hash = ~hash;
560 			slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
561 			slot += hidx & _PTEIDX_GROUP_IX;
562 			if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
563 				pSeries_lpar_hpte_invalidate(slot, va, psize,
564 							     ssize, local);
565 			} else {
566 				param[pix] = HBR_REQUEST | HBR_AVPN | slot;
567 				param[pix+1] = hpte_encode_avpn(va, psize,
568 								ssize);
569 				pix += 2;
570 				if (pix == 8) {
571 					rc = plpar_hcall9(H_BULK_REMOVE, param,
572 						param[0], param[1], param[2],
573 						param[3], param[4], param[5],
574 						param[6], param[7]);
575 					BUG_ON(rc != H_SUCCESS);
576 					pix = 0;
577 				}
578 			}
579 		} pte_iterate_hashed_end();
580 	}
581 	if (pix) {
582 		param[pix] = HBR_END;
583 		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
584 				  param[2], param[3], param[4], param[5],
585 				  param[6], param[7]);
586 		BUG_ON(rc != H_SUCCESS);
587 	}
588 
589 	if (lock_tlbie)
590 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
591 }
592 
593 void __init hpte_init_lpar(void)
594 {
595 	ppc_md.hpte_invalidate	= pSeries_lpar_hpte_invalidate;
596 	ppc_md.hpte_updatepp	= pSeries_lpar_hpte_updatepp;
597 	ppc_md.hpte_updateboltedpp = pSeries_lpar_hpte_updateboltedpp;
598 	ppc_md.hpte_insert	= pSeries_lpar_hpte_insert;
599 	ppc_md.hpte_remove	= pSeries_lpar_hpte_remove;
600 	ppc_md.flush_hash_range	= pSeries_lpar_flush_hash_range;
601 	ppc_md.hpte_clear_all   = pSeries_lpar_hptab_clear;
602 }
603