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1/*
2 *  linux/arch/m32r/mm/mmu.S
3 *
4 *  Copyright (C) 2001 by Hiroyuki Kondo
5 */
6
7#include <linux/linkage.h>
8#include <asm/assembler.h>
9#include <asm/smp.h>
10
11	.text
12#ifdef CONFIG_MMU
13
14#include <asm/mmu_context.h>
15#include <asm/page.h>
16#include <asm/pgtable.h>
17#include <asm/m32r.h>
18
19/*
20 * TLB Miss Exception handler
21 */
22	.balign	16
23ENTRY(tme_handler)
24	.global	tlb_entry_i_dat
25	.global	tlb_entry_d_dat
26
27	SWITCH_TO_KERNEL_STACK
28
29#if defined(CONFIG_ISA_M32R2)
30	st	r0, @-sp
31	st	r1, @-sp
32	st	r2, @-sp
33	st	r3, @-sp
34
35	seth	r3, #high(MMU_REG_BASE)
36	ld	r1, @(MESTS_offset, r3)	; r1: status     (MESTS reg.)
37	ld	r0, @(MDEVP_offset, r3)	; r0: PFN + ASID (MDEVP reg.)
38	st	r1, @(MESTS_offset, r3)	; clear status   (MESTS reg.)
39	and3	r1, r1, #(MESTS_IT)
40	bnez	r1, 1f			; instruction TLB miss?
41
42;; data TLB miss
43;;  input
44;;   r0: PFN + ASID (MDEVP reg.)
45;;   r1 - r3: free
46;;  output
47;;   r0: PFN + ASID
48;;   r1: TLB entry base address
49;;   r2: &tlb_entry_{i|d}_dat
50;;   r3: free
51
52#ifndef CONFIG_SMP
53	seth	r2, #high(tlb_entry_d_dat)
54	or3	r2, r2, #low(tlb_entry_d_dat)
55#else	/* CONFIG_SMP */
56	ldi	r1, #-8192
57	seth	r2, #high(tlb_entry_d_dat)
58	or3	r2, r2, #low(tlb_entry_d_dat)
59	and	r1, sp
60	ld	r1, @(16, r1)		; current_thread_info->cpu
61	slli	r1, #2
62	add	r2, r1
63#endif	/* !CONFIG_SMP */
64	seth	r1, #high(DTLB_BASE)
65	or3	r1, r1, #low(DTLB_BASE)
66	bra	2f
67
68	.balign	16
69	.fillinsn
701:
71;; instrucntion TLB miss
72;;  input
73;;   r0: MDEVP reg. (included ASID)
74;;   r1 - r3: free
75;;  output
76;;   r0: PFN + ASID
77;;   r1: TLB entry base address
78;;   r2: &tlb_entry_{i|d}_dat
79;;   r3: free
80	ldi	r3, #-4096
81	and3	r0, r0, #(MMU_CONTEXT_ASID_MASK)
82	mvfc	r1, bpc
83	and	r1, r3
84	or	r0, r1			; r0: PFN + ASID
85#ifndef CONFIG_SMP
86	seth	r2, #high(tlb_entry_i_dat)
87	or3	r2, r2, #low(tlb_entry_i_dat)
88#else	/* CONFIG_SMP */
89	ldi	r1, #-8192
90	seth	r2, #high(tlb_entry_i_dat)
91	or3	r2, r2, #low(tlb_entry_i_dat)
92	and	r1, sp
93	ld	r1, @(16, r1)		; current_thread_info->cpu
94	slli	r1, #2
95	add	r2, r1
96#endif	/* !CONFIG_SMP */
97	seth	r1, #high(ITLB_BASE)
98	or3	r1, r1, #low(ITLB_BASE)
99
100	.fillinsn
1012:
102;; select TLB entry
103;;  input
104;;   r0: PFN + ASID
105;;   r1: TLB entry base address
106;;   r2: &tlb_entry_{i|d}_dat
107;;   r3: free
108;;  output
109;;   r0: PFN + ASID
110;;   r1: TLB entry address
111;;   r2, r3: free
112#ifdef CONFIG_ISA_DUAL_ISSUE
113	ld	r3, @r2		||	srli	r1, #3
114#else
115	ld	r3, @r2
116	srli	r1, #3
117#endif
118	add	r1, r3
119	; tlb_entry_{d|i}_dat++;
120	addi	r3, #1
121	and3	r3, r3, #(NR_TLB_ENTRIES - 1)
122#ifdef CONFIG_ISA_DUAL_ISSUE
123	st	r3, @r2		||	slli	r1, #3
124#else
125	st	r3, @r2
126	slli	r1, #3
127#endif
128
129;; load pte
130;;  input
131;;   r0: PFN + ASID
132;;   r1: TLB entry address
133;;   r2, r3: free
134;;  output
135;;   r0: PFN + ASID
136;;   r1: TLB entry address
137;;   r2: pte_data
138;;   r3: free
139	; pgd = *(unsigned long *)MPTB;
140	ld24	r2, #(-MPTB - 1)
141	srl3	r3, r0, #22
142#ifdef CONFIG_ISA_DUAL_ISSUE
143	not	r2, r2		    ||	slli	r3, #2	; r3: pgd offset
144#else
145	not	r2, r2
146	slli	r3, #2
147#endif
148	ld	r2, @r2			; r2: pgd base addr (MPTB reg.)
149	or	r3, r2			; r3: pmd addr
150
151	; pmd = pmd_offset(pgd, address);
152	ld	r3, @r3			; r3: pmd data
153	ldi	r2, #-4096
154	beqz	r3, 3f			; pmd_none(*pmd) ?
155
156	; pte = pte_offset(pmd, address);
157	and	r2, r3			; r2: pte base addr
158	srl3	r3, r0, #10
159	and3	r3, r3, #0xffc		; r3: pte offset
160	or	r3, r2
161	seth	r2, #0x8000
162	or	r3, r2			; r3: pte addr
163
164	; pte_data = (unsigned long)pte_val(*pte);
165	ld	r2, @r3			; r2: pte data
166	and3	r3, r2, #2		; _PAGE_PRESENT(=2) check
167	beqz	r3, 3f
168
169	.fillinsn
1705:
171;; set tlb
172;;  input
173;;   r0: PFN + ASID
174;;   r1: TLB entry address
175;;   r2: pte_data
176;;   r3: free
177	st	r0, @r1			; set_tlb_tag(entry++, address);
178	st	r2, @+r1		; set_tlb_data(entry, pte_data);
179
180	.fillinsn
1816:
182	ld	r3, @sp+
183	ld	r2, @sp+
184	ld	r1, @sp+
185	ld	r0, @sp+
186	rte
187
188	.fillinsn
1893:
190;; error
191;;  input
192;;   r0: PFN + ASID
193;;   r1: TLB entry address
194;;   r2, r3: free
195;;  output
196;;   r0: PFN + ASID
197;;   r1: TLB entry address
198;;   r2: pte_data
199;;   r3: free
200#ifdef CONFIG_ISA_DUAL_ISSUE
201	bra	5b		    ||	ldi	r2, #2
202#else
203	ldi	r2, #2		; r2: pte_data = 0 | _PAGE_PRESENT(=2)
204	bra	5b
205#endif
206
207#elif defined (CONFIG_ISA_M32R)
208
209	st	sp, @-sp
210	st	r0, @-sp
211	st	r1, @-sp
212	st	r2, @-sp
213	st	r3, @-sp
214	st	r4, @-sp
215
216	seth	r3, #high(MMU_REG_BASE)
217	ld	r0, @(MDEVA_offset,r3)	; r0: address  (MDEVA reg.)
218	mvfc	r2, bpc			; r2: bpc
219	ld	r1, @(MESTS_offset,r3)	; r1: status   (MESTS reg.)
220	st	r1, @(MESTS_offset,r3)	; clear status (MESTS reg.)
221	and3	r1, r1, #(MESTS_IT)
222	beqz	r1, 1f			; data TLB miss?
223
224;; instrucntion TLB miss
225	mv	r0, r2			; address = bpc;
226	; entry = (unsigned long *)ITLB_BASE+tlb_entry_i*2;
227	seth	r3, #shigh(tlb_entry_i_dat)
228	ld	r4, @(low(tlb_entry_i_dat),r3)
229	sll3	r2, r4, #3
230	seth	r1, #high(ITLB_BASE)
231	or3	r1, r1, #low(ITLB_BASE)
232	add	r2, r1			; r2: entry
233	addi	r4, #1			; tlb_entry_i++;
234	and3	r4, r4, #(NR_TLB_ENTRIES-1)
235	st	r4, @(low(tlb_entry_i_dat),r3)
236	bra	2f
237	.fillinsn
2381:
239;; data TLB miss
240	; entry = (unsigned long *)DTLB_BASE+tlb_entry_d*2;
241	seth	r3, #shigh(tlb_entry_d_dat)
242	ld	r4, @(low(tlb_entry_d_dat),r3)
243	sll3	r2, r4, #3
244	seth	r1, #high(DTLB_BASE)
245	or3	r1, r1, #low(DTLB_BASE)
246	add	r2, r1			; r2: entry
247	addi	r4, #1			; tlb_entry_d++;
248	and3	r4, r4, #(NR_TLB_ENTRIES-1)
249	st	r4, @(low(tlb_entry_d_dat),r3)
250	.fillinsn
2512:
252;; load pte
253; r0: address, r2: entry
254; r1,r3,r4: (free)
255	; pgd = *(unsigned long *)MPTB;
256	ld24	r1, #(-MPTB-1)
257	not	r1, r1
258	ld	r1, @r1
259	srl3	r4, r0, #22
260	sll3	r3, r4, #2
261	add	r3, r1			; r3: pgd
262	; pmd = pmd_offset(pgd, address);
263	ld	r1, @r3			; r1: pmd
264	beqz	r1, 3f			; pmd_none(*pmd) ?
265;
266	and3	r1, r1, #0xeff
267	ldi	r4, #611		; _KERNPG_TABLE(=611)
268	bne	r1, r4, 3f		; !pmd_bad(*pmd) ?
269
270	.fillinsn
2714:
272	; pte = pte_offset(pmd, address);
273	ld	r4, @r3			; r4: pte
274	ldi	r3, #-4096
275	and	r4, r3
276	srl3	r3, r0, #10
277	and3	r3, r3, #0xffc
278	add	r4, r3
279	seth	r3, #0x8000
280	add	r4, r3			; r4: pte
281	; pte_data = (unsigned long)pte_val(*pte);
282	ld	r1, @r4			; r1: pte_data
283	and3	r3, r1, #2		; _PAGE_PRESENT(=2) check
284	beqz	r3, 3f
285
286	.fillinsn
287;; set tlb
288; r0: address, r1: pte_data, r2: entry
289; r3,r4: (free)
2905:
291	ldi	r3, #-4096		; set_tlb_tag(entry++, address);
292	and	r3, r0
293	seth	r4, #shigh(MASID)
294	ld	r4, @(low(MASID),r4)	; r4: MASID
295	and3	r4, r4, #(MMU_CONTEXT_ASID_MASK)
296	or	r3, r4
297	st	r3, @r2
298	st	r1, @(4,r2)		; set_tlb_data(entry, pte_data);
299
300	ld	r4, @sp+
301	ld	r3, @sp+
302	ld	r2, @sp+
303	ld	r1, @sp+
304	ld	r0, @sp+
305	ld	sp, @sp+
306	rte
307
308	.fillinsn
3093:
310	ldi	r1, #2			; r1: pte_data = 0 | _PAGE_PRESENT(=2)
311	bra	5b
312
313#else
314#error unknown isa configuration
315#endif
316
317ENTRY(init_tlb)
318;; Set MMU Register
319	seth	r0, #high(MMU_REG_BASE)	 ; Set MMU_REG_BASE higher
320	or3	r0, r0, #low(MMU_REG_BASE)  ; Set MMU_REG_BASE lower
321	ldi	r1, #0
322	st	r1, @(MPSZ_offset,r0)	; Set MPSZ Reg(Page size 4KB:0 16KB:1 64KB:2)
323	ldi	r1, #0
324	st	r1, @(MASID_offset,r0)	; Set ASID Zero
325
326;; Set TLB
327	seth	r0, #high(ITLB_BASE)	; Set ITLB_BASE higher
328	or3	r0, r0, #low(ITLB_BASE)	; Set ITLB_BASE lower
329	seth	r1, #high(DTLB_BASE)	; Set DTLB_BASE higher
330	or3	r1, r1, #low(DTLB_BASE)	; Set DTLB_BASE lower
331	ldi	r2, #0
332	ldi	r3, #NR_TLB_ENTRIES
333	addi	r0, #-4
334	addi	r1, #-4
335clear_tlb:
336	st	r2, @+r0		; VPA <- 0
337	st	r2, @+r0		; PPA <- 0
338	st	r2, @+r1		; VPA <- 0
339	st	r2, @+r1		; PPA <- 0
340	addi	r3, #-1
341	bnez	r3, clear_tlb
342;;
343	jmp	r14
344
345ENTRY(m32r_itlb_entrys)
346ENTRY(m32r_otlb_entrys)
347
348#endif  /* CONFIG_MMU */
349
350	.end
351