xref: /openbmc/linux/arch/mips/include/asm/stackframe.h (revision 4f3db074)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994, 95, 96, 99, 2001 Ralf Baechle
7  * Copyright (C) 1994, 1995, 1996 Paul M. Antoine.
8  * Copyright (C) 1999 Silicon Graphics, Inc.
9  * Copyright (C) 2007  Maciej W. Rozycki
10  */
11 #ifndef _ASM_STACKFRAME_H
12 #define _ASM_STACKFRAME_H
13 
14 #include <linux/threads.h>
15 
16 #include <asm/asm.h>
17 #include <asm/asmmacro.h>
18 #include <asm/mipsregs.h>
19 #include <asm/asm-offsets.h>
20 #include <asm/thread_info.h>
21 
22 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
23 #define STATMASK 0x3f
24 #else
25 #define STATMASK 0x1f
26 #endif
27 
28 		.macro	SAVE_AT
29 		.set	push
30 		.set	noat
31 		LONG_S	$1, PT_R1(sp)
32 		.set	pop
33 		.endm
34 
35 		.macro	SAVE_TEMP
36 #ifdef CONFIG_CPU_HAS_SMARTMIPS
37 		mflhxu	v1
38 		LONG_S	v1, PT_LO(sp)
39 		mflhxu	v1
40 		LONG_S	v1, PT_HI(sp)
41 		mflhxu	v1
42 		LONG_S	v1, PT_ACX(sp)
43 #elif !defined(CONFIG_CPU_MIPSR6)
44 		mfhi	v1
45 #endif
46 #ifdef CONFIG_32BIT
47 		LONG_S	$8, PT_R8(sp)
48 		LONG_S	$9, PT_R9(sp)
49 #endif
50 		LONG_S	$10, PT_R10(sp)
51 		LONG_S	$11, PT_R11(sp)
52 		LONG_S	$12, PT_R12(sp)
53 #if !defined(CONFIG_CPU_HAS_SMARTMIPS) && !defined(CONFIG_CPU_MIPSR6)
54 		LONG_S	v1, PT_HI(sp)
55 		mflo	v1
56 #endif
57 		LONG_S	$13, PT_R13(sp)
58 		LONG_S	$14, PT_R14(sp)
59 		LONG_S	$15, PT_R15(sp)
60 		LONG_S	$24, PT_R24(sp)
61 #if !defined(CONFIG_CPU_HAS_SMARTMIPS) && !defined(CONFIG_CPU_MIPSR6)
62 		LONG_S	v1, PT_LO(sp)
63 #endif
64 #ifdef CONFIG_CPU_CAVIUM_OCTEON
65 		/*
66 		 * The Octeon multiplier state is affected by general
67 		 * multiply instructions. It must be saved before and
68 		 * kernel code might corrupt it
69 		 */
70 		jal     octeon_mult_save
71 #endif
72 		.endm
73 
74 		.macro	SAVE_STATIC
75 		LONG_S	$16, PT_R16(sp)
76 		LONG_S	$17, PT_R17(sp)
77 		LONG_S	$18, PT_R18(sp)
78 		LONG_S	$19, PT_R19(sp)
79 		LONG_S	$20, PT_R20(sp)
80 		LONG_S	$21, PT_R21(sp)
81 		LONG_S	$22, PT_R22(sp)
82 		LONG_S	$23, PT_R23(sp)
83 		LONG_S	$30, PT_R30(sp)
84 		.endm
85 
86 #ifdef CONFIG_SMP
87 		.macro	get_saved_sp	/* SMP variation */
88 		ASM_CPUID_MFC0	k0, ASM_SMP_CPUID_REG
89 #if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
90 		lui	k1, %hi(kernelsp)
91 #else
92 		lui	k1, %highest(kernelsp)
93 		daddiu	k1, %higher(kernelsp)
94 		dsll	k1, 16
95 		daddiu	k1, %hi(kernelsp)
96 		dsll	k1, 16
97 #endif
98 		LONG_SRL	k0, SMP_CPUID_PTRSHIFT
99 		LONG_ADDU	k1, k0
100 		LONG_L	k1, %lo(kernelsp)(k1)
101 		.endm
102 
103 		.macro	set_saved_sp stackp temp temp2
104 		ASM_CPUID_MFC0	\temp, ASM_SMP_CPUID_REG
105 		LONG_SRL	\temp, SMP_CPUID_PTRSHIFT
106 		LONG_S	\stackp, kernelsp(\temp)
107 		.endm
108 #else /* !CONFIG_SMP */
109 		.macro	get_saved_sp	/* Uniprocessor variation */
110 #ifdef CONFIG_CPU_JUMP_WORKAROUNDS
111 		/*
112 		 * Clear BTB (branch target buffer), forbid RAS (return address
113 		 * stack) to workaround the Out-of-order Issue in Loongson2F
114 		 * via its diagnostic register.
115 		 */
116 		move	k0, ra
117 		jal	1f
118 		 nop
119 1:		jal	1f
120 		 nop
121 1:		jal	1f
122 		 nop
123 1:		jal	1f
124 		 nop
125 1:		move	ra, k0
126 		li	k0, 3
127 		mtc0	k0, $22
128 #endif /* CONFIG_CPU_JUMP_WORKAROUNDS */
129 #if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
130 		lui	k1, %hi(kernelsp)
131 #else
132 		lui	k1, %highest(kernelsp)
133 		daddiu	k1, %higher(kernelsp)
134 		dsll	k1, k1, 16
135 		daddiu	k1, %hi(kernelsp)
136 		dsll	k1, k1, 16
137 #endif
138 		LONG_L	k1, %lo(kernelsp)(k1)
139 		.endm
140 
141 		.macro	set_saved_sp stackp temp temp2
142 		LONG_S	\stackp, kernelsp
143 		.endm
144 #endif
145 
146 		.macro	SAVE_SOME
147 		.set	push
148 		.set	noat
149 		.set	reorder
150 		mfc0	k0, CP0_STATUS
151 		sll	k0, 3		/* extract cu0 bit */
152 		.set	noreorder
153 		bltz	k0, 8f
154 		 move	k1, sp
155 		.set	reorder
156 		/* Called from user mode, new stack. */
157 		get_saved_sp
158 #ifndef CONFIG_CPU_DADDI_WORKAROUNDS
159 8:		move	k0, sp
160 		PTR_SUBU sp, k1, PT_SIZE
161 #else
162 		.set	at=k0
163 8:		PTR_SUBU k1, PT_SIZE
164 		.set	noat
165 		move	k0, sp
166 		move	sp, k1
167 #endif
168 		LONG_S	k0, PT_R29(sp)
169 		LONG_S	$3, PT_R3(sp)
170 		/*
171 		 * You might think that you don't need to save $0,
172 		 * but the FPU emulator and gdb remote debug stub
173 		 * need it to operate correctly
174 		 */
175 		LONG_S	$0, PT_R0(sp)
176 		mfc0	v1, CP0_STATUS
177 		LONG_S	$2, PT_R2(sp)
178 		LONG_S	v1, PT_STATUS(sp)
179 		LONG_S	$4, PT_R4(sp)
180 		mfc0	v1, CP0_CAUSE
181 		LONG_S	$5, PT_R5(sp)
182 		LONG_S	v1, PT_CAUSE(sp)
183 		LONG_S	$6, PT_R6(sp)
184 		MFC0	v1, CP0_EPC
185 		LONG_S	$7, PT_R7(sp)
186 #ifdef CONFIG_64BIT
187 		LONG_S	$8, PT_R8(sp)
188 		LONG_S	$9, PT_R9(sp)
189 #endif
190 		LONG_S	v1, PT_EPC(sp)
191 		LONG_S	$25, PT_R25(sp)
192 		LONG_S	$28, PT_R28(sp)
193 		LONG_S	$31, PT_R31(sp)
194 		ori	$28, sp, _THREAD_MASK
195 		xori	$28, _THREAD_MASK
196 #ifdef CONFIG_CPU_CAVIUM_OCTEON
197 		.set    mips64
198 		pref    0, 0($28)       /* Prefetch the current pointer */
199 #endif
200 		.set	pop
201 		.endm
202 
203 		.macro	SAVE_ALL
204 		SAVE_SOME
205 		SAVE_AT
206 		SAVE_TEMP
207 		SAVE_STATIC
208 		.endm
209 
210 		.macro	RESTORE_AT
211 		.set	push
212 		.set	noat
213 		LONG_L	$1,  PT_R1(sp)
214 		.set	pop
215 		.endm
216 
217 		.macro	RESTORE_TEMP
218 #ifdef CONFIG_CPU_CAVIUM_OCTEON
219 		/* Restore the Octeon multiplier state */
220 		jal	octeon_mult_restore
221 #endif
222 #ifdef CONFIG_CPU_HAS_SMARTMIPS
223 		LONG_L	$24, PT_ACX(sp)
224 		mtlhx	$24
225 		LONG_L	$24, PT_HI(sp)
226 		mtlhx	$24
227 		LONG_L	$24, PT_LO(sp)
228 		mtlhx	$24
229 #elif !defined(CONFIG_CPU_MIPSR6)
230 		LONG_L	$24, PT_LO(sp)
231 		mtlo	$24
232 		LONG_L	$24, PT_HI(sp)
233 		mthi	$24
234 #endif
235 #ifdef CONFIG_32BIT
236 		LONG_L	$8, PT_R8(sp)
237 		LONG_L	$9, PT_R9(sp)
238 #endif
239 		LONG_L	$10, PT_R10(sp)
240 		LONG_L	$11, PT_R11(sp)
241 		LONG_L	$12, PT_R12(sp)
242 		LONG_L	$13, PT_R13(sp)
243 		LONG_L	$14, PT_R14(sp)
244 		LONG_L	$15, PT_R15(sp)
245 		LONG_L	$24, PT_R24(sp)
246 		.endm
247 
248 		.macro	RESTORE_STATIC
249 		LONG_L	$16, PT_R16(sp)
250 		LONG_L	$17, PT_R17(sp)
251 		LONG_L	$18, PT_R18(sp)
252 		LONG_L	$19, PT_R19(sp)
253 		LONG_L	$20, PT_R20(sp)
254 		LONG_L	$21, PT_R21(sp)
255 		LONG_L	$22, PT_R22(sp)
256 		LONG_L	$23, PT_R23(sp)
257 		LONG_L	$30, PT_R30(sp)
258 		.endm
259 
260 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
261 
262 		.macro	RESTORE_SOME
263 		.set	push
264 		.set	reorder
265 		.set	noat
266 		mfc0	a0, CP0_STATUS
267 		li	v1, 0xff00
268 		ori	a0, STATMASK
269 		xori	a0, STATMASK
270 		mtc0	a0, CP0_STATUS
271 		and	a0, v1
272 		LONG_L	v0, PT_STATUS(sp)
273 		nor	v1, $0, v1
274 		and	v0, v1
275 		or	v0, a0
276 		mtc0	v0, CP0_STATUS
277 		LONG_L	$31, PT_R31(sp)
278 		LONG_L	$28, PT_R28(sp)
279 		LONG_L	$25, PT_R25(sp)
280 		LONG_L	$7,  PT_R7(sp)
281 		LONG_L	$6,  PT_R6(sp)
282 		LONG_L	$5,  PT_R5(sp)
283 		LONG_L	$4,  PT_R4(sp)
284 		LONG_L	$3,  PT_R3(sp)
285 		LONG_L	$2,  PT_R2(sp)
286 		.set	pop
287 		.endm
288 
289 		.macro	RESTORE_SP_AND_RET
290 		.set	push
291 		.set	noreorder
292 		LONG_L	k0, PT_EPC(sp)
293 		LONG_L	sp, PT_R29(sp)
294 		jr	k0
295 		 rfe
296 		.set	pop
297 		.endm
298 
299 #else
300 		.macro	RESTORE_SOME
301 		.set	push
302 		.set	reorder
303 		.set	noat
304 		mfc0	a0, CP0_STATUS
305 		ori	a0, STATMASK
306 		xori	a0, STATMASK
307 		mtc0	a0, CP0_STATUS
308 		li	v1, 0xff00
309 		and	a0, v1
310 		LONG_L	v0, PT_STATUS(sp)
311 		nor	v1, $0, v1
312 		and	v0, v1
313 		or	v0, a0
314 		mtc0	v0, CP0_STATUS
315 		LONG_L	v1, PT_EPC(sp)
316 		MTC0	v1, CP0_EPC
317 		LONG_L	$31, PT_R31(sp)
318 		LONG_L	$28, PT_R28(sp)
319 		LONG_L	$25, PT_R25(sp)
320 #ifdef CONFIG_64BIT
321 		LONG_L	$8, PT_R8(sp)
322 		LONG_L	$9, PT_R9(sp)
323 #endif
324 		LONG_L	$7,  PT_R7(sp)
325 		LONG_L	$6,  PT_R6(sp)
326 		LONG_L	$5,  PT_R5(sp)
327 		LONG_L	$4,  PT_R4(sp)
328 		LONG_L	$3,  PT_R3(sp)
329 		LONG_L	$2,  PT_R2(sp)
330 		.set	pop
331 		.endm
332 
333 		.macro	RESTORE_SP_AND_RET
334 		LONG_L	sp, PT_R29(sp)
335 		.set	arch=r4000
336 		eret
337 		.set	mips0
338 		.endm
339 
340 #endif
341 
342 		.macro	RESTORE_SP
343 		LONG_L	sp, PT_R29(sp)
344 		.endm
345 
346 		.macro	RESTORE_ALL
347 		RESTORE_TEMP
348 		RESTORE_STATIC
349 		RESTORE_AT
350 		RESTORE_SOME
351 		RESTORE_SP
352 		.endm
353 
354 		.macro	RESTORE_ALL_AND_RET
355 		RESTORE_TEMP
356 		RESTORE_STATIC
357 		RESTORE_AT
358 		RESTORE_SOME
359 		RESTORE_SP_AND_RET
360 		.endm
361 
362 /*
363  * Move to kernel mode and disable interrupts.
364  * Set cp0 enable bit as sign that we're running on the kernel stack
365  */
366 		.macro	CLI
367 		mfc0	t0, CP0_STATUS
368 		li	t1, ST0_CU0 | STATMASK
369 		or	t0, t1
370 		xori	t0, STATMASK
371 		mtc0	t0, CP0_STATUS
372 		irq_disable_hazard
373 		.endm
374 
375 /*
376  * Move to kernel mode and enable interrupts.
377  * Set cp0 enable bit as sign that we're running on the kernel stack
378  */
379 		.macro	STI
380 		mfc0	t0, CP0_STATUS
381 		li	t1, ST0_CU0 | STATMASK
382 		or	t0, t1
383 		xori	t0, STATMASK & ~1
384 		mtc0	t0, CP0_STATUS
385 		irq_enable_hazard
386 		.endm
387 
388 /*
389  * Just move to kernel mode and leave interrupts as they are.  Note
390  * for the R3000 this means copying the previous enable from IEp.
391  * Set cp0 enable bit as sign that we're running on the kernel stack
392  */
393 		.macro	KMODE
394 		mfc0	t0, CP0_STATUS
395 		li	t1, ST0_CU0 | (STATMASK & ~1)
396 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
397 		andi	t2, t0, ST0_IEP
398 		srl	t2, 2
399 		or	t0, t2
400 #endif
401 		or	t0, t1
402 		xori	t0, STATMASK & ~1
403 		mtc0	t0, CP0_STATUS
404 		irq_disable_hazard
405 		.endm
406 
407 #endif /* _ASM_STACKFRAME_H */
408