1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _SPARC64_TSB_H
3#define _SPARC64_TSB_H
4
5/* The sparc64 TSB is similar to the powerpc hashtables.  It's a
6 * power-of-2 sized table of TAG/PTE pairs.  The cpu precomputes
7 * pointers into this table for 8K and 64K page sizes, and also a
8 * comparison TAG based upon the virtual address and context which
9 * faults.
10 *
11 * TLB miss trap handler software does the actual lookup via something
12 * of the form:
13 *
14 * 	ldxa		[%g0] ASI_{D,I}MMU_TSB_8KB_PTR, %g1
15 * 	ldxa		[%g0] ASI_{D,I}MMU, %g6
16 *	sllx		%g6, 22, %g6
17 *	srlx		%g6, 22, %g6
18 * 	ldda		[%g1] ASI_NUCLEUS_QUAD_LDD, %g4
19 * 	cmp		%g4, %g6
20 * 	bne,pn	%xcc, tsb_miss_{d,i}tlb
21 * 	 mov		FAULT_CODE_{D,I}TLB, %g3
22 * 	stxa		%g5, [%g0] ASI_{D,I}TLB_DATA_IN
23 * 	retry
24 *
25 *
26 * Each 16-byte slot of the TSB is the 8-byte tag and then the 8-byte
27 * PTE.  The TAG is of the same layout as the TLB TAG TARGET mmu
28 * register which is:
29 *
30 * -------------------------------------------------
31 * |  -  |  CONTEXT |  -  |    VADDR bits 63:22    |
32 * -------------------------------------------------
33 *  63 61 60      48 47 42 41                     0
34 *
35 * But actually, since we use per-mm TSB's, we zero out the CONTEXT
36 * field.
37 *
38 * Like the powerpc hashtables we need to use locking in order to
39 * synchronize while we update the entries.  PTE updates need locking
40 * as well.
41 *
42 * We need to carefully choose a lock bits for the TSB entry.  We
43 * choose to use bit 47 in the tag.  Also, since we never map anything
44 * at page zero in context zero, we use zero as an invalid tag entry.
45 * When the lock bit is set, this forces a tag comparison failure.
46 */
47
48#define TSB_TAG_LOCK_BIT	47
49#define TSB_TAG_LOCK_HIGH	(1 << (TSB_TAG_LOCK_BIT - 32))
50
51#define TSB_TAG_INVALID_BIT	46
52#define TSB_TAG_INVALID_HIGH	(1 << (TSB_TAG_INVALID_BIT - 32))
53
54/* Some cpus support physical address quad loads.  We want to use
55 * those if possible so we don't need to hard-lock the TSB mapping
56 * into the TLB.  We encode some instruction patching in order to
57 * support this.
58 *
59 * The kernel TSB is locked into the TLB by virtue of being in the
60 * kernel image, so we don't play these games for swapper_tsb access.
61 */
62#ifndef __ASSEMBLY__
63struct tsb_ldquad_phys_patch_entry {
64	unsigned int	addr;
65	unsigned int	sun4u_insn;
66	unsigned int	sun4v_insn;
67};
68extern struct tsb_ldquad_phys_patch_entry __tsb_ldquad_phys_patch,
69	__tsb_ldquad_phys_patch_end;
70
71struct tsb_phys_patch_entry {
72	unsigned int	addr;
73	unsigned int	insn;
74};
75extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end;
76#endif
77#define TSB_LOAD_QUAD(TSB, REG)	\
78661:	ldda		[TSB] ASI_NUCLEUS_QUAD_LDD, REG; \
79	.section	.tsb_ldquad_phys_patch, "ax"; \
80	.word		661b; \
81	ldda		[TSB] ASI_QUAD_LDD_PHYS, REG; \
82	ldda		[TSB] ASI_QUAD_LDD_PHYS_4V, REG; \
83	.previous
84
85#define TSB_LOAD_TAG_HIGH(TSB, REG) \
86661:	lduwa		[TSB] ASI_N, REG; \
87	.section	.tsb_phys_patch, "ax"; \
88	.word		661b; \
89	lduwa		[TSB] ASI_PHYS_USE_EC, REG; \
90	.previous
91
92#define TSB_LOAD_TAG(TSB, REG) \
93661:	ldxa		[TSB] ASI_N, REG; \
94	.section	.tsb_phys_patch, "ax"; \
95	.word		661b; \
96	ldxa		[TSB] ASI_PHYS_USE_EC, REG; \
97	.previous
98
99#define TSB_CAS_TAG_HIGH(TSB, REG1, REG2) \
100661:	casa		[TSB] ASI_N, REG1, REG2; \
101	.section	.tsb_phys_patch, "ax"; \
102	.word		661b; \
103	casa		[TSB] ASI_PHYS_USE_EC, REG1, REG2; \
104	.previous
105
106#define TSB_CAS_TAG(TSB, REG1, REG2) \
107661:	casxa		[TSB] ASI_N, REG1, REG2; \
108	.section	.tsb_phys_patch, "ax"; \
109	.word		661b; \
110	casxa		[TSB] ASI_PHYS_USE_EC, REG1, REG2; \
111	.previous
112
113#define TSB_STORE(ADDR, VAL) \
114661:	stxa		VAL, [ADDR] ASI_N; \
115	.section	.tsb_phys_patch, "ax"; \
116	.word		661b; \
117	stxa		VAL, [ADDR] ASI_PHYS_USE_EC; \
118	.previous
119
120#define TSB_LOCK_TAG(TSB, REG1, REG2)	\
12199:	TSB_LOAD_TAG_HIGH(TSB, REG1);	\
122	sethi	%hi(TSB_TAG_LOCK_HIGH), REG2;\
123	andcc	REG1, REG2, %g0;	\
124	bne,pn	%icc, 99b;		\
125	 nop;				\
126	TSB_CAS_TAG_HIGH(TSB, REG1, REG2);	\
127	cmp	REG1, REG2;		\
128	bne,pn	%icc, 99b;		\
129	 nop;				\
130
131#define TSB_WRITE(TSB, TTE, TAG) \
132	add	TSB, 0x8, TSB;   \
133	TSB_STORE(TSB, TTE);     \
134	sub	TSB, 0x8, TSB;   \
135	TSB_STORE(TSB, TAG);
136
137	/* Do a kernel page table walk.  Leaves valid PTE value in
138	 * REG1.  Jumps to FAIL_LABEL on early page table walk
139	 * termination.  VADDR will not be clobbered, but REG2 will.
140	 *
141	 * There are two masks we must apply to propagate bits from
142	 * the virtual address into the PTE physical address field
143	 * when dealing with huge pages.  This is because the page
144	 * table boundaries do not match the huge page size(s) the
145	 * hardware supports.
146	 *
147	 * In these cases we propagate the bits that are below the
148	 * page table level where we saw the huge page mapping, but
149	 * are still within the relevant physical bits for the huge
150	 * page size in question.  So for PMD mappings (which fall on
151	 * bit 23, for 8MB per PMD) we must propagate bit 22 for a
152	 * 4MB huge page.  For huge PUDs (which fall on bit 33, for
153	 * 8GB per PUD), we have to accommodate 256MB and 2GB huge
154	 * pages.  So for those we propagate bits 32 to 28.
155	 */
156#define KERN_PGTABLE_WALK(VADDR, REG1, REG2, FAIL_LABEL)	\
157	sethi		%hi(swapper_pg_dir), REG1; \
158	or		REG1, %lo(swapper_pg_dir), REG1; \
159	sllx		VADDR, 64 - (PGDIR_SHIFT + PGDIR_BITS), REG2; \
160	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
161	andn		REG2, 0x7, REG2; \
162	ldx		[REG1 + REG2], REG1; \
163	brz,pn		REG1, FAIL_LABEL; \
164	 sllx		VADDR, 64 - (PUD_SHIFT + PUD_BITS), REG2; \
165	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
166	andn		REG2, 0x7, REG2; \
167	ldxa		[REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
168	brz,pn		REG1, FAIL_LABEL; \
169	sethi		%uhi(_PAGE_PUD_HUGE), REG2; \
170	brz,pn		REG1, FAIL_LABEL; \
171	 sllx		REG2, 32, REG2; \
172	andcc		REG1, REG2, %g0; \
173	sethi		%hi(0xf8000000), REG2; \
174	bne,pt		%xcc, 697f; \
175	 sllx		REG2, 1, REG2; \
176	sllx		VADDR, 64 - (PMD_SHIFT + PMD_BITS), REG2; \
177	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
178	andn		REG2, 0x7, REG2; \
179	ldxa		[REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
180	sethi		%uhi(_PAGE_PMD_HUGE), REG2; \
181	brz,pn		REG1, FAIL_LABEL; \
182	 sllx		REG2, 32, REG2; \
183	andcc		REG1, REG2, %g0; \
184	be,pn		%xcc, 698f; \
185	 sethi		%hi(0x400000), REG2; \
186697:	brgez,pn	REG1, FAIL_LABEL; \
187	 andn		REG1, REG2, REG1; \
188	and		VADDR, REG2, REG2; \
189	ba,pt		%xcc, 699f; \
190	 or		REG1, REG2, REG1; \
191698:	sllx		VADDR, 64 - PMD_SHIFT, REG2; \
192	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
193	andn		REG2, 0x7, REG2; \
194	ldxa		[REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
195	brgez,pn	REG1, FAIL_LABEL; \
196	 nop; \
197699:
198
199	/* PUD has been loaded into REG1, interpret the value, seeing
200	 * if it is a HUGE PUD or a normal one.  If it is not valid
201	 * then jump to FAIL_LABEL.  If it is a HUGE PUD, and it
202	 * translates to a valid PTE, branch to PTE_LABEL.
203	 *
204	 * We have to propagate bits [32:22] from the virtual address
205	 * to resolve at 4M granularity.
206	 */
207#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
208#define USER_PGTABLE_CHECK_PUD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, PTE_LABEL) \
209700:	ba 700f;					\
210	 nop;						\
211	.section	.pud_huge_patch, "ax";		\
212	.word		700b;				\
213	nop;						\
214	.previous;					\
215	brz,pn		REG1, FAIL_LABEL;		\
216	 sethi		%uhi(_PAGE_PUD_HUGE), REG2;	\
217	sllx		REG2, 32, REG2;			\
218	andcc		REG1, REG2, %g0;		\
219	be,pt		%xcc, 700f;			\
220	 sethi		%hi(0xffe00000), REG2;		\
221	sllx		REG2, 1, REG2;			\
222	brgez,pn	REG1, FAIL_LABEL;		\
223	 andn		REG1, REG2, REG1;		\
224	and		VADDR, REG2, REG2;		\
225	brlz,pt		REG1, PTE_LABEL;		\
226	 or		REG1, REG2, REG1;		\
227700:
228#else
229#define USER_PGTABLE_CHECK_PUD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, PTE_LABEL) \
230	brz,pn		REG1, FAIL_LABEL; \
231	 nop;
232#endif
233
234	/* PMD has been loaded into REG1, interpret the value, seeing
235	 * if it is a HUGE PMD or a normal one.  If it is not valid
236	 * then jump to FAIL_LABEL.  If it is a HUGE PMD, and it
237	 * translates to a valid PTE, branch to PTE_LABEL.
238	 *
239	 * We have to propagate the 4MB bit of the virtual address
240	 * because we are fabricating 8MB pages using 4MB hw pages.
241	 */
242#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
243#define USER_PGTABLE_CHECK_PMD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, PTE_LABEL) \
244	brz,pn		REG1, FAIL_LABEL;		\
245	 sethi		%uhi(_PAGE_PMD_HUGE), REG2;	\
246	sllx		REG2, 32, REG2;			\
247	andcc		REG1, REG2, %g0;		\
248	be,pt		%xcc, 700f;			\
249	 sethi		%hi(4 * 1024 * 1024), REG2;	\
250	brgez,pn	REG1, FAIL_LABEL;		\
251	 andn		REG1, REG2, REG1;		\
252	and		VADDR, REG2, REG2;		\
253	brlz,pt		REG1, PTE_LABEL;		\
254	 or		REG1, REG2, REG1;		\
255700:
256#else
257#define USER_PGTABLE_CHECK_PMD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, PTE_LABEL) \
258	brz,pn		REG1, FAIL_LABEL; \
259	 nop;
260#endif
261
262	/* Do a user page table walk in MMU globals.  Leaves final,
263	 * valid, PTE value in REG1.  Jumps to FAIL_LABEL on early
264	 * page table walk termination or if the PTE is not valid.
265	 *
266	 * Physical base of page tables is in PHYS_PGD which will not
267	 * be modified.
268	 *
269	 * VADDR will not be clobbered, but REG1 and REG2 will.
270	 */
271#define USER_PGTABLE_WALK_TL1(VADDR, PHYS_PGD, REG1, REG2, FAIL_LABEL)	\
272	sllx		VADDR, 64 - (PGDIR_SHIFT + PGDIR_BITS), REG2; \
273	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
274	andn		REG2, 0x7, REG2; \
275	ldxa		[PHYS_PGD + REG2] ASI_PHYS_USE_EC, REG1; \
276	brz,pn		REG1, FAIL_LABEL; \
277	 sllx		VADDR, 64 - (PUD_SHIFT + PUD_BITS), REG2; \
278	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
279	andn		REG2, 0x7, REG2; \
280	ldxa		[REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
281	USER_PGTABLE_CHECK_PUD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, 800f) \
282	brz,pn		REG1, FAIL_LABEL; \
283	 sllx		VADDR, 64 - (PMD_SHIFT + PMD_BITS), REG2; \
284	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
285	andn		REG2, 0x7, REG2; \
286	ldxa		[REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
287	USER_PGTABLE_CHECK_PMD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, 800f) \
288	sllx		VADDR, 64 - PMD_SHIFT, REG2; \
289	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
290	andn		REG2, 0x7, REG2; \
291	add		REG1, REG2, REG1; \
292	ldxa		[REG1] ASI_PHYS_USE_EC, REG1; \
293	brgez,pn	REG1, FAIL_LABEL; \
294	 nop; \
295800:
296
297/* Lookup a OBP mapping on VADDR in the prom_trans[] table at TL>0.
298 * If no entry is found, FAIL_LABEL will be branched to.  On success
299 * the resulting PTE value will be left in REG1.  VADDR is preserved
300 * by this routine.
301 */
302#define OBP_TRANS_LOOKUP(VADDR, REG1, REG2, REG3, FAIL_LABEL) \
303	sethi		%hi(prom_trans), REG1; \
304	or		REG1, %lo(prom_trans), REG1; \
30597:	ldx		[REG1 + 0x00], REG2; \
306	brz,pn		REG2, FAIL_LABEL; \
307	 nop; \
308	ldx		[REG1 + 0x08], REG3; \
309	add		REG2, REG3, REG3; \
310	cmp		REG2, VADDR; \
311	bgu,pt		%xcc, 98f; \
312	 cmp		VADDR, REG3; \
313	bgeu,pt		%xcc, 98f; \
314	 ldx		[REG1 + 0x10], REG3; \
315	sub		VADDR, REG2, REG2; \
316	ba,pt		%xcc, 99f; \
317	 add		REG3, REG2, REG1; \
31898:	ba,pt		%xcc, 97b; \
319	 add		REG1, (3 * 8), REG1; \
32099:
321
322	/* We use a 32K TSB for the whole kernel, this allows to
323	 * handle about 16MB of modules and vmalloc mappings without
324	 * incurring many hash conflicts.
325	 */
326#define KERNEL_TSB_SIZE_BYTES	(32 * 1024)
327#define KERNEL_TSB_NENTRIES	\
328	(KERNEL_TSB_SIZE_BYTES / 16)
329#define KERNEL_TSB4M_NENTRIES	4096
330
331	/* Do a kernel TSB lookup at tl>0 on VADDR+TAG, branch to OK_LABEL
332	 * on TSB hit.  REG1, REG2, REG3, and REG4 are used as temporaries
333	 * and the found TTE will be left in REG1.  REG3 and REG4 must
334	 * be an even/odd pair of registers.
335	 *
336	 * VADDR and TAG will be preserved and not clobbered by this macro.
337	 */
338#define KERN_TSB_LOOKUP_TL1(VADDR, TAG, REG1, REG2, REG3, REG4, OK_LABEL) \
339661:	sethi		%uhi(swapper_tsb), REG1; \
340	sethi		%hi(swapper_tsb), REG2; \
341	or		REG1, %ulo(swapper_tsb), REG1; \
342	or		REG2, %lo(swapper_tsb), REG2; \
343	.section	.swapper_tsb_phys_patch, "ax"; \
344	.word		661b; \
345	.previous; \
346	sllx		REG1, 32, REG1; \
347	or		REG1, REG2, REG1; \
348	srlx		VADDR, PAGE_SHIFT, REG2; \
349	and		REG2, (KERNEL_TSB_NENTRIES - 1), REG2; \
350	sllx		REG2, 4, REG2; \
351	add		REG1, REG2, REG2; \
352	TSB_LOAD_QUAD(REG2, REG3); \
353	cmp		REG3, TAG; \
354	be,a,pt		%xcc, OK_LABEL; \
355	 mov		REG4, REG1;
356
357#ifndef CONFIG_DEBUG_PAGEALLOC
358	/* This version uses a trick, the TAG is already (VADDR >> 22) so
359	 * we can make use of that for the index computation.
360	 */
361#define KERN_TSB4M_LOOKUP_TL1(TAG, REG1, REG2, REG3, REG4, OK_LABEL) \
362661:	sethi		%uhi(swapper_4m_tsb), REG1; \
363	sethi		%hi(swapper_4m_tsb), REG2; \
364	or		REG1, %ulo(swapper_4m_tsb), REG1; \
365	or		REG2, %lo(swapper_4m_tsb), REG2; \
366	.section	.swapper_4m_tsb_phys_patch, "ax"; \
367	.word		661b; \
368	.previous; \
369	sllx		REG1, 32, REG1; \
370	or		REG1, REG2, REG1; \
371	and		TAG, (KERNEL_TSB4M_NENTRIES - 1), REG2; \
372	sllx		REG2, 4, REG2; \
373	add		REG1, REG2, REG2; \
374	TSB_LOAD_QUAD(REG2, REG3); \
375	cmp		REG3, TAG; \
376	be,a,pt		%xcc, OK_LABEL; \
377	 mov		REG4, REG1;
378#endif
379
380#endif /* !(_SPARC64_TSB_H) */
381