xref: /openbmc/linux/arch/mips/include/asm/processor.h (revision 65417d9f)
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 Waldorf GMBH
7  * Copyright (C) 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2003 Ralf Baechle
8  * Copyright (C) 1996 Paul M. Antoine
9  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
10  */
11 #ifndef _ASM_PROCESSOR_H
12 #define _ASM_PROCESSOR_H
13 
14 #include <linux/atomic.h>
15 #include <linux/cpumask.h>
16 #include <linux/threads.h>
17 
18 #include <asm/cachectl.h>
19 #include <asm/cpu.h>
20 #include <asm/cpu-info.h>
21 #include <asm/dsemul.h>
22 #include <asm/mipsregs.h>
23 #include <asm/prefetch.h>
24 
25 /*
26  * Return current * instruction pointer ("program counter").
27  */
28 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
29 
30 /*
31  * System setup and hardware flags..
32  */
33 
34 extern unsigned int vced_count, vcei_count;
35 
36 /*
37  * MIPS does have an arch_pick_mmap_layout()
38  */
39 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
40 
41 #ifdef CONFIG_32BIT
42 #ifdef CONFIG_KVM_GUEST
43 /* User space process size is limited to 1GB in KVM Guest Mode */
44 #define TASK_SIZE	0x3fff8000UL
45 #else
46 /*
47  * User space process size: 2GB. This is hardcoded into a few places,
48  * so don't change it unless you know what you are doing.
49  */
50 #define TASK_SIZE	0x80000000UL
51 #endif
52 
53 #define STACK_TOP_MAX	TASK_SIZE
54 
55 #define TASK_IS_32BIT_ADDR 1
56 
57 #endif
58 
59 #ifdef CONFIG_64BIT
60 /*
61  * User space process size: 1TB. This is hardcoded into a few places,
62  * so don't change it unless you know what you are doing.  TASK_SIZE
63  * is limited to 1TB by the R4000 architecture; R10000 and better can
64  * support 16TB; the architectural reserve for future expansion is
65  * 8192EB ...
66  */
67 #define TASK_SIZE32	0x7fff8000UL
68 #ifdef CONFIG_MIPS_VA_BITS_48
69 #define TASK_SIZE64     (0x1UL << ((cpu_data[0].vmbits>48)?48:cpu_data[0].vmbits))
70 #else
71 #define TASK_SIZE64     0x10000000000UL
72 #endif
73 #define TASK_SIZE (test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
74 #define STACK_TOP_MAX	TASK_SIZE64
75 
76 #define TASK_SIZE_OF(tsk)						\
77 	(test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
78 
79 #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR)
80 
81 #endif
82 
83 /*
84  * One page above the stack is used for branch delay slot "emulation".
85  * See dsemul.c for details.
86  */
87 #define STACK_TOP	((TASK_SIZE & PAGE_MASK) - PAGE_SIZE)
88 
89 /*
90  * This decides where the kernel will search for a free chunk of vm
91  * space during mmap's.
92  */
93 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
94 
95 
96 #define NUM_FPU_REGS	32
97 
98 #ifdef CONFIG_CPU_HAS_MSA
99 # define FPU_REG_WIDTH	128
100 #else
101 # define FPU_REG_WIDTH	64
102 #endif
103 
104 union fpureg {
105 	__u32	val32[FPU_REG_WIDTH / 32];
106 	__u64	val64[FPU_REG_WIDTH / 64];
107 };
108 
109 #ifdef CONFIG_CPU_LITTLE_ENDIAN
110 # define FPR_IDX(width, idx)	(idx)
111 #else
112 # define FPR_IDX(width, idx)	((idx) ^ ((64 / (width)) - 1))
113 #endif
114 
115 #define BUILD_FPR_ACCESS(width) \
116 static inline u##width get_fpr##width(union fpureg *fpr, unsigned idx)	\
117 {									\
118 	return fpr->val##width[FPR_IDX(width, idx)];			\
119 }									\
120 									\
121 static inline void set_fpr##width(union fpureg *fpr, unsigned idx,	\
122 				  u##width val)				\
123 {									\
124 	fpr->val##width[FPR_IDX(width, idx)] = val;			\
125 }
126 
127 BUILD_FPR_ACCESS(32)
128 BUILD_FPR_ACCESS(64)
129 
130 /*
131  * It would be nice to add some more fields for emulator statistics,
132  * the additional information is private to the FPU emulator for now.
133  * See arch/mips/include/asm/fpu_emulator.h.
134  */
135 
136 struct mips_fpu_struct {
137 	union fpureg	fpr[NUM_FPU_REGS];
138 	unsigned int	fcr31;
139 	unsigned int	msacsr;
140 };
141 
142 #define NUM_DSP_REGS   6
143 
144 typedef __u32 dspreg_t;
145 
146 struct mips_dsp_state {
147 	dspreg_t	dspr[NUM_DSP_REGS];
148 	unsigned int	dspcontrol;
149 };
150 
151 #define INIT_CPUMASK { \
152 	{0,} \
153 }
154 
155 struct mips3264_watch_reg_state {
156 	/* The width of watchlo is 32 in a 32 bit kernel and 64 in a
157 	   64 bit kernel.  We use unsigned long as it has the same
158 	   property. */
159 	unsigned long watchlo[NUM_WATCH_REGS];
160 	/* Only the mask and IRW bits from watchhi. */
161 	u16 watchhi[NUM_WATCH_REGS];
162 };
163 
164 union mips_watch_reg_state {
165 	struct mips3264_watch_reg_state mips3264;
166 };
167 
168 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
169 
170 struct octeon_cop2_state {
171 	/* DMFC2 rt, 0x0201 */
172 	unsigned long	cop2_crc_iv;
173 	/* DMFC2 rt, 0x0202 (Set with DMTC2 rt, 0x1202) */
174 	unsigned long	cop2_crc_length;
175 	/* DMFC2 rt, 0x0200 (set with DMTC2 rt, 0x4200) */
176 	unsigned long	cop2_crc_poly;
177 	/* DMFC2 rt, 0x0402; DMFC2 rt, 0x040A */
178 	unsigned long	cop2_llm_dat[2];
179        /* DMFC2 rt, 0x0084 */
180 	unsigned long	cop2_3des_iv;
181 	/* DMFC2 rt, 0x0080; DMFC2 rt, 0x0081; DMFC2 rt, 0x0082 */
182 	unsigned long	cop2_3des_key[3];
183 	/* DMFC2 rt, 0x0088 (Set with DMTC2 rt, 0x0098) */
184 	unsigned long	cop2_3des_result;
185 	/* DMFC2 rt, 0x0111 (FIXME: Read Pass1 Errata) */
186 	unsigned long	cop2_aes_inp0;
187 	/* DMFC2 rt, 0x0102; DMFC2 rt, 0x0103 */
188 	unsigned long	cop2_aes_iv[2];
189 	/* DMFC2 rt, 0x0104; DMFC2 rt, 0x0105; DMFC2 rt, 0x0106; DMFC2
190 	 * rt, 0x0107 */
191 	unsigned long	cop2_aes_key[4];
192 	/* DMFC2 rt, 0x0110 */
193 	unsigned long	cop2_aes_keylen;
194 	/* DMFC2 rt, 0x0100; DMFC2 rt, 0x0101 */
195 	unsigned long	cop2_aes_result[2];
196 	/* DMFC2 rt, 0x0240; DMFC2 rt, 0x0241; DMFC2 rt, 0x0242; DMFC2
197 	 * rt, 0x0243; DMFC2 rt, 0x0244; DMFC2 rt, 0x0245; DMFC2 rt,
198 	 * 0x0246; DMFC2 rt, 0x0247; DMFC2 rt, 0x0248; DMFC2 rt,
199 	 * 0x0249; DMFC2 rt, 0x024A; DMFC2 rt, 0x024B; DMFC2 rt,
200 	 * 0x024C; DMFC2 rt, 0x024D; DMFC2 rt, 0x024E - Pass2 */
201 	unsigned long	cop2_hsh_datw[15];
202 	/* DMFC2 rt, 0x0250; DMFC2 rt, 0x0251; DMFC2 rt, 0x0252; DMFC2
203 	 * rt, 0x0253; DMFC2 rt, 0x0254; DMFC2 rt, 0x0255; DMFC2 rt,
204 	 * 0x0256; DMFC2 rt, 0x0257 - Pass2 */
205 	unsigned long	cop2_hsh_ivw[8];
206 	/* DMFC2 rt, 0x0258; DMFC2 rt, 0x0259 - Pass2 */
207 	unsigned long	cop2_gfm_mult[2];
208 	/* DMFC2 rt, 0x025E - Pass2 */
209 	unsigned long	cop2_gfm_poly;
210 	/* DMFC2 rt, 0x025A; DMFC2 rt, 0x025B - Pass2 */
211 	unsigned long	cop2_gfm_result[2];
212 	/* DMFC2 rt, 0x24F, DMFC2 rt, 0x50, OCTEON III */
213 	unsigned long	cop2_sha3[2];
214 };
215 #define COP2_INIT						\
216 	.cp2			= {0,},
217 
218 struct octeon_cvmseg_state {
219 	unsigned long cvmseg[CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE]
220 			    [cpu_dcache_line_size() / sizeof(unsigned long)];
221 };
222 
223 #elif defined(CONFIG_CPU_XLP)
224 struct nlm_cop2_state {
225 	u64	rx[4];
226 	u64	tx[4];
227 	u32	tx_msg_status;
228 	u32	rx_msg_status;
229 };
230 
231 #define COP2_INIT						\
232 	.cp2			= {{0}, {0}, 0, 0},
233 #else
234 #define COP2_INIT
235 #endif
236 
237 typedef struct {
238 	unsigned long seg;
239 } mm_segment_t;
240 
241 #ifdef CONFIG_CPU_HAS_MSA
242 # define ARCH_MIN_TASKALIGN	16
243 # define FPU_ALIGN		__aligned(16)
244 #else
245 # define ARCH_MIN_TASKALIGN	8
246 # define FPU_ALIGN
247 #endif
248 
249 struct mips_abi;
250 
251 /*
252  * If you change thread_struct remember to change the #defines below too!
253  */
254 struct thread_struct {
255 	/* Saved main processor registers. */
256 	unsigned long reg16;
257 	unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
258 	unsigned long reg29, reg30, reg31;
259 
260 	/* Saved cp0 stuff. */
261 	unsigned long cp0_status;
262 
263 	/* Saved fpu/fpu emulator stuff. */
264 	struct mips_fpu_struct fpu FPU_ALIGN;
265 	/* Assigned branch delay slot 'emulation' frame */
266 	atomic_t bd_emu_frame;
267 	/* PC of the branch from a branch delay slot 'emulation' */
268 	unsigned long bd_emu_branch_pc;
269 	/* PC to continue from following a branch delay slot 'emulation' */
270 	unsigned long bd_emu_cont_pc;
271 #ifdef CONFIG_MIPS_MT_FPAFF
272 	/* Emulated instruction count */
273 	unsigned long emulated_fp;
274 	/* Saved per-thread scheduler affinity mask */
275 	cpumask_t user_cpus_allowed;
276 #endif /* CONFIG_MIPS_MT_FPAFF */
277 
278 	/* Saved state of the DSP ASE, if available. */
279 	struct mips_dsp_state dsp;
280 
281 	/* Saved watch register state, if available. */
282 	union mips_watch_reg_state watch;
283 
284 	/* Other stuff associated with the thread. */
285 	unsigned long cp0_badvaddr;	/* Last user fault */
286 	unsigned long cp0_baduaddr;	/* Last kernel fault accessing USEG */
287 	unsigned long error_code;
288 	unsigned long trap_nr;
289 #ifdef CONFIG_CPU_CAVIUM_OCTEON
290 	struct octeon_cop2_state cp2 __attribute__ ((__aligned__(128)));
291 	struct octeon_cvmseg_state cvmseg __attribute__ ((__aligned__(128)));
292 #endif
293 #ifdef CONFIG_CPU_XLP
294 	struct nlm_cop2_state cp2;
295 #endif
296 	struct mips_abi *abi;
297 };
298 
299 #ifdef CONFIG_MIPS_MT_FPAFF
300 #define FPAFF_INIT						\
301 	.emulated_fp			= 0,			\
302 	.user_cpus_allowed		= INIT_CPUMASK,
303 #else
304 #define FPAFF_INIT
305 #endif /* CONFIG_MIPS_MT_FPAFF */
306 
307 #define INIT_THREAD  {						\
308 	/*							\
309 	 * Saved main processor registers			\
310 	 */							\
311 	.reg16			= 0,				\
312 	.reg17			= 0,				\
313 	.reg18			= 0,				\
314 	.reg19			= 0,				\
315 	.reg20			= 0,				\
316 	.reg21			= 0,				\
317 	.reg22			= 0,				\
318 	.reg23			= 0,				\
319 	.reg29			= 0,				\
320 	.reg30			= 0,				\
321 	.reg31			= 0,				\
322 	/*							\
323 	 * Saved cp0 stuff					\
324 	 */							\
325 	.cp0_status		= 0,				\
326 	/*							\
327 	 * Saved FPU/FPU emulator stuff				\
328 	 */							\
329 	.fpu			= {				\
330 		.fpr		= {{{0,},},},			\
331 		.fcr31		= 0,				\
332 		.msacsr		= 0,				\
333 	},							\
334 	/*							\
335 	 * FPU affinity state (null if not FPAFF)		\
336 	 */							\
337 	FPAFF_INIT						\
338 	/* Delay slot emulation */				\
339 	.bd_emu_frame = ATOMIC_INIT(BD_EMUFRAME_NONE),		\
340 	.bd_emu_branch_pc = 0,					\
341 	.bd_emu_cont_pc = 0,					\
342 	/*							\
343 	 * Saved DSP stuff					\
344 	 */							\
345 	.dsp			= {				\
346 		.dspr		= {0, },			\
347 		.dspcontrol	= 0,				\
348 	},							\
349 	/*							\
350 	 * saved watch register stuff				\
351 	 */							\
352 	.watch = {{{0,},},},					\
353 	/*							\
354 	 * Other stuff associated with the process		\
355 	 */							\
356 	.cp0_badvaddr		= 0,				\
357 	.cp0_baduaddr		= 0,				\
358 	.error_code		= 0,				\
359 	.trap_nr		= 0,				\
360 	/*							\
361 	 * Platform specific cop2 registers(null if no COP2)	\
362 	 */							\
363 	COP2_INIT						\
364 }
365 
366 struct task_struct;
367 
368 /* Free all resources held by a thread. */
369 #define release_thread(thread) do { } while(0)
370 
371 /*
372  * Do necessary setup to start up a newly executed thread.
373  */
374 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
375 
376 static inline void flush_thread(void)
377 {
378 }
379 
380 unsigned long get_wchan(struct task_struct *p);
381 
382 #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
383 			 THREAD_SIZE - 32 - sizeof(struct pt_regs))
384 #define task_pt_regs(tsk) ((struct pt_regs *)__KSTK_TOS(tsk))
385 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->cp0_epc)
386 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[29])
387 #define KSTK_STATUS(tsk) (task_pt_regs(tsk)->cp0_status)
388 
389 #define cpu_relax()	barrier()
390 
391 /*
392  * Return_address is a replacement for __builtin_return_address(count)
393  * which on certain architectures cannot reasonably be implemented in GCC
394  * (MIPS, Alpha) or is unusable with -fomit-frame-pointer (i386).
395  * Note that __builtin_return_address(x>=1) is forbidden because GCC
396  * aborts compilation on some CPUs.  It's simply not possible to unwind
397  * some CPU's stackframes.
398  *
399  * __builtin_return_address works only for non-leaf functions.	We avoid the
400  * overhead of a function call by forcing the compiler to save the return
401  * address register on the stack.
402  */
403 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
404 
405 #ifdef CONFIG_CPU_HAS_PREFETCH
406 
407 #define ARCH_HAS_PREFETCH
408 #define prefetch(x) __builtin_prefetch((x), 0, 1)
409 
410 #define ARCH_HAS_PREFETCHW
411 #define prefetchw(x) __builtin_prefetch((x), 1, 1)
412 
413 #endif
414 
415 /*
416  * Functions & macros implementing the PR_GET_FP_MODE & PR_SET_FP_MODE options
417  * to the prctl syscall.
418  */
419 extern int mips_get_process_fp_mode(struct task_struct *task);
420 extern int mips_set_process_fp_mode(struct task_struct *task,
421 				    unsigned int value);
422 
423 #define GET_FP_MODE(task)		mips_get_process_fp_mode(task)
424 #define SET_FP_MODE(task,value)		mips_set_process_fp_mode(task, value)
425 
426 #endif /* _ASM_PROCESSOR_H */
427