xref: /openbmc/linux/arch/powerpc/mm/nohash/tlb_low.S (revision 35267cea)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * This file contains low-level functions for performing various
4 * types of TLB invalidations on various processors with no hash
5 * table.
6 *
7 * This file implements the following functions for all no-hash
8 * processors. Some aren't implemented for some variants. Some
9 * are inline in tlbflush.h
10 *
11 *	- tlbil_va
12 *	- tlbil_pid
13 *	- tlbil_all
14 *	- tlbivax_bcast
15 *
16 * Code mostly moved over from misc_32.S
17 *
18 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
19 *
20 * Partially rewritten by Cort Dougan (cort@cs.nmt.edu)
21 * Paul Mackerras, Kumar Gala and Benjamin Herrenschmidt.
22 */
23
24#include <asm/reg.h>
25#include <asm/page.h>
26#include <asm/cputable.h>
27#include <asm/mmu.h>
28#include <asm/ppc_asm.h>
29#include <asm/asm-offsets.h>
30#include <asm/processor.h>
31#include <asm/bug.h>
32#include <asm/asm-compat.h>
33#include <asm/feature-fixups.h>
34
35#if defined(CONFIG_40x)
36
37/*
38 * 40x implementation needs only tlbil_va
39 */
40_GLOBAL(__tlbil_va)
41	/* We run the search with interrupts disabled because we have to change
42	 * the PID and I don't want to preempt when that happens.
43	 */
44	mfmsr	r5
45	mfspr	r6,SPRN_PID
46	wrteei	0
47	mtspr	SPRN_PID,r4
48	tlbsx.	r3, 0, r3
49	mtspr	SPRN_PID,r6
50	wrtee	r5
51	bne	1f
52	sync
53	/* There are only 64 TLB entries, so r3 < 64, which means bit 25 is
54	 * clear. Since 25 is the V bit in the TLB_TAG, loading this value
55	 * will invalidate the TLB entry. */
56	tlbwe	r3, r3, TLB_TAG
57	isync
581:	blr
59
60#elif defined(CONFIG_PPC_8xx)
61
62/*
63 * Nothing to do for 8xx, everything is inline
64 */
65
66#elif defined(CONFIG_44x) /* Includes 47x */
67
68/*
69 * 440 implementation uses tlbsx/we for tlbil_va and a full sweep
70 * of the TLB for everything else.
71 */
72_GLOBAL(__tlbil_va)
73	mfspr	r5,SPRN_MMUCR
74	mfmsr   r10
75
76	/*
77	 * We write 16 bits of STID since 47x supports that much, we
78	 * will never be passed out of bounds values on 440 (hopefully)
79	 */
80	rlwimi  r5,r4,0,16,31
81
82	/* We have to run the search with interrupts disabled, otherwise
83	 * an interrupt which causes a TLB miss can clobber the MMUCR
84	 * between the mtspr and the tlbsx.
85	 *
86	 * Critical and Machine Check interrupts take care of saving
87	 * and restoring MMUCR, so only normal interrupts have to be
88	 * taken care of.
89	 */
90	wrteei	0
91	mtspr	SPRN_MMUCR,r5
92	tlbsx.	r6,0,r3
93	bne	10f
94	sync
95#ifndef CONFIG_PPC_47x
96	/* On 440 There are only 64 TLB entries, so r3 < 64, which means bit
97	 * 22, is clear.  Since 22 is the V bit in the TLB_PAGEID, loading this
98	 * value will invalidate the TLB entry.
99	 */
100	tlbwe	r6,r6,PPC44x_TLB_PAGEID
101#else
102	oris	r7,r6,0x8000	/* specify way explicitly */
103	clrrwi	r4,r3,12	/* get an EPN for the hashing with V = 0 */
104	ori	r4,r4,PPC47x_TLBE_SIZE
105	tlbwe   r4,r7,0		/* write it */
106#endif /* !CONFIG_PPC_47x */
107	isync
10810:	wrtee	r10
109	blr
110
111_GLOBAL(_tlbil_all)
112_GLOBAL(_tlbil_pid)
113#ifndef CONFIG_PPC_47x
114	li	r3,0
115	sync
116
117	/* Load high watermark */
118	lis	r4,tlb_44x_hwater@ha
119	lwz	r5,tlb_44x_hwater@l(r4)
120
1211:	tlbwe	r3,r3,PPC44x_TLB_PAGEID
122	addi	r3,r3,1
123	cmpw	0,r3,r5
124	ble	1b
125
126	isync
127	blr
128#else
129	/* 476 variant. There's not simple way to do this, hopefully we'll
130	 * try to limit the amount of such full invalidates
131	 */
132	mfmsr	r11		/* Interrupts off */
133	wrteei	0
134	li	r3,-1		/* Current set */
135	lis	r10,tlb_47x_boltmap@h
136	ori	r10,r10,tlb_47x_boltmap@l
137	lis	r7,0x8000	/* Specify way explicitly */
138
139	b	9f		/* For each set */
140
1411:	li	r9,4		/* Number of ways */
142	li	r4,0		/* Current way */
143	li	r6,0		/* Default entry value 0 */
144	andi.	r0,r8,1		/* Check if way 0 is bolted */
145	mtctr	r9		/* Load way counter */
146	bne-	3f		/* Bolted, skip loading it */
147
1482:	/* For each way */
149	or	r5,r3,r4	/* Make way|index for tlbre */
150	rlwimi	r5,r5,16,8,15	/* Copy index into position */
151	tlbre	r6,r5,0		/* Read entry */
1523:	addis	r4,r4,0x2000	/* Next way */
153	andi.	r0,r6,PPC47x_TLB0_VALID /* Valid entry ? */
154	beq	4f		/* Nope, skip it */
155	rlwimi	r7,r5,0,1,2	/* Insert way number */
156	rlwinm	r6,r6,0,21,19	/* Clear V */
157	tlbwe   r6,r7,0		/* Write it */
1584:	bdnz	2b		/* Loop for each way */
159	srwi	r8,r8,1		/* Next boltmap bit */
1609:	cmpwi	cr1,r3,255	/* Last set done ? */
161	addi	r3,r3,1		/* Next set */
162	beq	cr1,1f		/* End of loop */
163	andi.	r0,r3,0x1f	/* Need to load a new boltmap word ? */
164	bne	1b		/* No, loop */
165	lwz	r8,0(r10)	/* Load boltmap entry */
166	addi	r10,r10,4	/* Next word */
167	b	1b		/* Then loop */
1681:	isync			/* Sync shadows */
169	wrtee	r11
170	blr
171#endif /* !CONFIG_PPC_47x */
172
173#ifdef CONFIG_PPC_47x
174
175/*
176 * _tlbivax_bcast is only on 47x. We don't bother doing a runtime
177 * check though, it will blow up soon enough if we mistakenly try
178 * to use it on a 440.
179 */
180_GLOBAL(_tlbivax_bcast)
181	mfspr	r5,SPRN_MMUCR
182	mfmsr	r10
183	rlwimi	r5,r4,0,16,31
184	wrteei	0
185	mtspr	SPRN_MMUCR,r5
186	isync
187	PPC_TLBIVAX(0, R3)
188	isync
189	eieio
190	tlbsync
191BEGIN_FTR_SECTION
192	b	1f
193END_FTR_SECTION_IFSET(CPU_FTR_476_DD2)
194	sync
195	wrtee	r10
196	blr
197/*
198 * DD2 HW could hang if in instruction fetch happens before msync completes.
199 * Touch enough instruction cache lines to ensure cache hits
200 */
2011:	mflr	r9
202	bl	2f
2032:	mflr	r6
204	li	r7,32
205	PPC_ICBT(0,R6,R7)		/* touch next cache line */
206	add	r6,r6,r7
207	PPC_ICBT(0,R6,R7)		/* touch next cache line */
208	add	r6,r6,r7
209	PPC_ICBT(0,R6,R7)		/* touch next cache line */
210	sync
211	nop
212	nop
213	nop
214	nop
215	nop
216	nop
217	nop
218	nop
219	mtlr	r9
220	wrtee	r10
221	blr
222#endif /* CONFIG_PPC_47x */
223
224#elif defined(CONFIG_FSL_BOOKE)
225/*
226 * FSL BookE implementations.
227 *
228 * Since feature sections are using _SECTION_ELSE we need
229 * to have the larger code path before the _SECTION_ELSE
230 */
231
232/*
233 * Flush MMU TLB on the local processor
234 */
235_GLOBAL(_tlbil_all)
236BEGIN_MMU_FTR_SECTION
237	li	r3,(MMUCSR0_TLBFI)@l
238	mtspr	SPRN_MMUCSR0, r3
2391:
240	mfspr	r3,SPRN_MMUCSR0
241	andi.	r3,r3,MMUCSR0_TLBFI@l
242	bne	1b
243MMU_FTR_SECTION_ELSE
244	PPC_TLBILX_ALL(0,R0)
245ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_TLBILX)
246	msync
247	isync
248	blr
249
250_GLOBAL(_tlbil_pid)
251BEGIN_MMU_FTR_SECTION
252	slwi	r3,r3,16
253	mfmsr	r10
254	wrteei	0
255	mfspr	r4,SPRN_MAS6	/* save MAS6 */
256	mtspr	SPRN_MAS6,r3
257	PPC_TLBILX_PID(0,R0)
258	mtspr	SPRN_MAS6,r4	/* restore MAS6 */
259	wrtee	r10
260MMU_FTR_SECTION_ELSE
261	li	r3,(MMUCSR0_TLBFI)@l
262	mtspr	SPRN_MMUCSR0, r3
2631:
264	mfspr	r3,SPRN_MMUCSR0
265	andi.	r3,r3,MMUCSR0_TLBFI@l
266	bne	1b
267ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBILX)
268	msync
269	isync
270	blr
271
272/*
273 * Flush MMU TLB for a particular address, but only on the local processor
274 * (no broadcast)
275 */
276_GLOBAL(__tlbil_va)
277	mfmsr	r10
278	wrteei	0
279	slwi	r4,r4,16
280	ori	r4,r4,(MAS6_ISIZE(BOOK3E_PAGESZ_4K))@l
281	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
282BEGIN_MMU_FTR_SECTION
283	tlbsx	0,r3
284	mfspr	r4,SPRN_MAS1		/* check valid */
285	andis.	r3,r4,MAS1_VALID@h
286	beq	1f
287	rlwinm	r4,r4,0,1,31
288	mtspr	SPRN_MAS1,r4
289	tlbwe
290MMU_FTR_SECTION_ELSE
291	PPC_TLBILX_VA(0,R3)
292ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_TLBILX)
293	msync
294	isync
2951:	wrtee	r10
296	blr
297#elif defined(CONFIG_PPC_BOOK3E)
298/*
299 * New Book3E (>= 2.06) implementation
300 *
301 * Note: We may be able to get away without the interrupt masking stuff
302 * if we save/restore MAS6 on exceptions that might modify it
303 */
304_GLOBAL(_tlbil_pid)
305	slwi	r4,r3,MAS6_SPID_SHIFT
306	mfmsr	r10
307	wrteei	0
308	mtspr	SPRN_MAS6,r4
309	PPC_TLBILX_PID(0,R0)
310	wrtee	r10
311	msync
312	isync
313	blr
314
315_GLOBAL(_tlbil_pid_noind)
316	slwi	r4,r3,MAS6_SPID_SHIFT
317	mfmsr	r10
318	ori	r4,r4,MAS6_SIND
319	wrteei	0
320	mtspr	SPRN_MAS6,r4
321	PPC_TLBILX_PID(0,R0)
322	wrtee	r10
323	msync
324	isync
325	blr
326
327_GLOBAL(_tlbil_all)
328	PPC_TLBILX_ALL(0,R0)
329	msync
330	isync
331	blr
332
333_GLOBAL(_tlbil_va)
334	mfmsr	r10
335	wrteei	0
336	cmpwi	cr0,r6,0
337	slwi	r4,r4,MAS6_SPID_SHIFT
338	rlwimi	r4,r5,MAS6_ISIZE_SHIFT,MAS6_ISIZE_MASK
339	beq	1f
340	rlwimi	r4,r6,MAS6_SIND_SHIFT,MAS6_SIND
3411:	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
342	PPC_TLBILX_VA(0,R3)
343	msync
344	isync
345	wrtee	r10
346	blr
347
348_GLOBAL(_tlbivax_bcast)
349	mfmsr	r10
350	wrteei	0
351	cmpwi	cr0,r6,0
352	slwi	r4,r4,MAS6_SPID_SHIFT
353	rlwimi	r4,r5,MAS6_ISIZE_SHIFT,MAS6_ISIZE_MASK
354	beq	1f
355	rlwimi	r4,r6,MAS6_SIND_SHIFT,MAS6_SIND
3561:	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
357	PPC_TLBIVAX(0,R3)
358	eieio
359	tlbsync
360	sync
361	wrtee	r10
362	blr
363#else
364#error Unsupported processor type !
365#endif
366
367#if defined(CONFIG_PPC_FSL_BOOK3E)
368/*
369 * extern void loadcam_entry(unsigned int index)
370 *
371 * Load TLBCAM[index] entry in to the L2 CAM MMU
372 * Must preserve r7, r8, r9, r10 and r11
373 */
374_GLOBAL(loadcam_entry)
375	mflr	r5
376	LOAD_REG_ADDR_PIC(r4, TLBCAM)
377	mtlr	r5
378	mulli	r5,r3,TLBCAM_SIZE
379	add	r3,r5,r4
380	lwz	r4,TLBCAM_MAS0(r3)
381	mtspr	SPRN_MAS0,r4
382	lwz	r4,TLBCAM_MAS1(r3)
383	mtspr	SPRN_MAS1,r4
384	PPC_LL	r4,TLBCAM_MAS2(r3)
385	mtspr	SPRN_MAS2,r4
386	lwz	r4,TLBCAM_MAS3(r3)
387	mtspr	SPRN_MAS3,r4
388BEGIN_MMU_FTR_SECTION
389	lwz	r4,TLBCAM_MAS7(r3)
390	mtspr	SPRN_MAS7,r4
391END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
392	isync
393	tlbwe
394	isync
395	blr
396
397/*
398 * Load multiple TLB entries at once, using an alternate-space
399 * trampoline so that we don't have to care about whether the same
400 * TLB entry maps us before and after.
401 *
402 * r3 = first entry to write
403 * r4 = number of entries to write
404 * r5 = temporary tlb entry
405 */
406_GLOBAL(loadcam_multi)
407	mflr	r8
408	/* Don't switch to AS=1 if already there */
409	mfmsr	r11
410	andi.	r11,r11,MSR_IS
411	bne	10f
412
413	/*
414	 * Set up temporary TLB entry that is the same as what we're
415	 * running from, but in AS=1.
416	 */
417	bl	1f
4181:	mflr	r6
419	tlbsx	0,r8
420	mfspr	r6,SPRN_MAS1
421	ori	r6,r6,MAS1_TS
422	mtspr	SPRN_MAS1,r6
423	mfspr	r6,SPRN_MAS0
424	rlwimi	r6,r5,MAS0_ESEL_SHIFT,MAS0_ESEL_MASK
425	mr	r7,r5
426	mtspr	SPRN_MAS0,r6
427	isync
428	tlbwe
429	isync
430
431	/* Switch to AS=1 */
432	mfmsr	r6
433	ori	r6,r6,MSR_IS|MSR_DS
434	mtmsr	r6
435	isync
436
43710:
438	mr	r9,r3
439	add	r10,r3,r4
4402:	bl	loadcam_entry
441	addi	r9,r9,1
442	cmpw	r9,r10
443	mr	r3,r9
444	blt	2b
445
446	/* Don't return to AS=0 if we were in AS=1 at function start */
447	andi.	r11,r11,MSR_IS
448	bne	3f
449
450	/* Return to AS=0 and clear the temporary entry */
451	mfmsr	r6
452	rlwinm.	r6,r6,0,~(MSR_IS|MSR_DS)
453	mtmsr	r6
454	isync
455
456	li	r6,0
457	mtspr	SPRN_MAS1,r6
458	rlwinm	r6,r7,MAS0_ESEL_SHIFT,MAS0_ESEL_MASK
459	oris	r6,r6,MAS0_TLBSEL(1)@h
460	mtspr	SPRN_MAS0,r6
461	isync
462	tlbwe
463	isync
464
4653:
466	mtlr	r8
467	blr
468#endif
469