xref: /openbmc/linux/arch/mips/include/asm/processor.h (revision 6f69e2a3)
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/sizes.h>
17 #include <linux/threads.h>
18 
19 #include <asm/cachectl.h>
20 #include <asm/cpu.h>
21 #include <asm/cpu-info.h>
22 #include <asm/dsemul.h>
23 #include <asm/mipsregs.h>
24 #include <asm/prefetch.h>
25 
26 /*
27  * System setup and hardware flags..
28  */
29 
30 extern unsigned int vced_count, vcei_count;
31 
32 #ifdef CONFIG_32BIT
33 #ifdef CONFIG_KVM_GUEST
34 /* User space process size is limited to 1GB in KVM Guest Mode */
35 #define TASK_SIZE	0x3fff8000UL
36 #else
37 /*
38  * User space process size: 2GB. This is hardcoded into a few places,
39  * so don't change it unless you know what you are doing.
40  */
41 #define TASK_SIZE	0x80000000UL
42 #endif
43 
44 #define STACK_TOP_MAX	TASK_SIZE
45 
46 #define TASK_IS_32BIT_ADDR 1
47 
48 #endif
49 
50 #ifdef CONFIG_64BIT
51 /*
52  * User space process size: 1TB. This is hardcoded into a few places,
53  * so don't change it unless you know what you are doing.  TASK_SIZE
54  * is limited to 1TB by the R4000 architecture; R10000 and better can
55  * support 16TB; the architectural reserve for future expansion is
56  * 8192EB ...
57  */
58 #define TASK_SIZE32	0x7fff8000UL
59 #ifdef CONFIG_MIPS_VA_BITS_48
60 #define TASK_SIZE64     (0x1UL << ((cpu_data[0].vmbits>48)?48:cpu_data[0].vmbits))
61 #else
62 #define TASK_SIZE64     0x10000000000UL
63 #endif
64 #define TASK_SIZE (test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
65 #define STACK_TOP_MAX	TASK_SIZE64
66 
67 #define TASK_SIZE_OF(tsk)						\
68 	(test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
69 
70 #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR)
71 
72 #endif
73 
74 #define VDSO_RANDOMIZE_SIZE	(TASK_IS_32BIT_ADDR ? SZ_1M : SZ_64M)
75 
76 extern unsigned long mips_stack_top(void);
77 #define STACK_TOP		mips_stack_top()
78 
79 /*
80  * This decides where the kernel will search for a free chunk of vm
81  * space during mmap's.
82  */
83 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
84 
85 
86 #define NUM_FPU_REGS	32
87 
88 #ifdef CONFIG_CPU_HAS_MSA
89 # define FPU_REG_WIDTH	128
90 #else
91 # define FPU_REG_WIDTH	64
92 #endif
93 
94 union fpureg {
95 	__u32	val32[FPU_REG_WIDTH / 32];
96 	__u64	val64[FPU_REG_WIDTH / 64];
97 };
98 
99 #ifdef CONFIG_CPU_LITTLE_ENDIAN
100 # define FPR_IDX(width, idx)	(idx)
101 #else
102 # define FPR_IDX(width, idx)	((idx) ^ ((64 / (width)) - 1))
103 #endif
104 
105 #define BUILD_FPR_ACCESS(width) \
106 static inline u##width get_fpr##width(union fpureg *fpr, unsigned idx)	\
107 {									\
108 	return fpr->val##width[FPR_IDX(width, idx)];			\
109 }									\
110 									\
111 static inline void set_fpr##width(union fpureg *fpr, unsigned idx,	\
112 				  u##width val)				\
113 {									\
114 	fpr->val##width[FPR_IDX(width, idx)] = val;			\
115 }
116 
117 BUILD_FPR_ACCESS(32)
118 BUILD_FPR_ACCESS(64)
119 
120 /*
121  * It would be nice to add some more fields for emulator statistics,
122  * the additional information is private to the FPU emulator for now.
123  * See arch/mips/include/asm/fpu_emulator.h.
124  */
125 
126 struct mips_fpu_struct {
127 	union fpureg	fpr[NUM_FPU_REGS];
128 	unsigned int	fcr31;
129 	unsigned int	msacsr;
130 };
131 
132 #define NUM_DSP_REGS   6
133 
134 typedef unsigned long dspreg_t;
135 
136 struct mips_dsp_state {
137 	dspreg_t	dspr[NUM_DSP_REGS];
138 	unsigned int	dspcontrol;
139 };
140 
141 #define INIT_CPUMASK { \
142 	{0,} \
143 }
144 
145 struct mips3264_watch_reg_state {
146 	/* The width of watchlo is 32 in a 32 bit kernel and 64 in a
147 	   64 bit kernel.  We use unsigned long as it has the same
148 	   property. */
149 	unsigned long watchlo[NUM_WATCH_REGS];
150 	/* Only the mask and IRW bits from watchhi. */
151 	u16 watchhi[NUM_WATCH_REGS];
152 };
153 
154 union mips_watch_reg_state {
155 	struct mips3264_watch_reg_state mips3264;
156 };
157 
158 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
159 
160 struct octeon_cop2_state {
161 	/* DMFC2 rt, 0x0201 */
162 	unsigned long	cop2_crc_iv;
163 	/* DMFC2 rt, 0x0202 (Set with DMTC2 rt, 0x1202) */
164 	unsigned long	cop2_crc_length;
165 	/* DMFC2 rt, 0x0200 (set with DMTC2 rt, 0x4200) */
166 	unsigned long	cop2_crc_poly;
167 	/* DMFC2 rt, 0x0402; DMFC2 rt, 0x040A */
168 	unsigned long	cop2_llm_dat[2];
169        /* DMFC2 rt, 0x0084 */
170 	unsigned long	cop2_3des_iv;
171 	/* DMFC2 rt, 0x0080; DMFC2 rt, 0x0081; DMFC2 rt, 0x0082 */
172 	unsigned long	cop2_3des_key[3];
173 	/* DMFC2 rt, 0x0088 (Set with DMTC2 rt, 0x0098) */
174 	unsigned long	cop2_3des_result;
175 	/* DMFC2 rt, 0x0111 (FIXME: Read Pass1 Errata) */
176 	unsigned long	cop2_aes_inp0;
177 	/* DMFC2 rt, 0x0102; DMFC2 rt, 0x0103 */
178 	unsigned long	cop2_aes_iv[2];
179 	/* DMFC2 rt, 0x0104; DMFC2 rt, 0x0105; DMFC2 rt, 0x0106; DMFC2
180 	 * rt, 0x0107 */
181 	unsigned long	cop2_aes_key[4];
182 	/* DMFC2 rt, 0x0110 */
183 	unsigned long	cop2_aes_keylen;
184 	/* DMFC2 rt, 0x0100; DMFC2 rt, 0x0101 */
185 	unsigned long	cop2_aes_result[2];
186 	/* DMFC2 rt, 0x0240; DMFC2 rt, 0x0241; DMFC2 rt, 0x0242; DMFC2
187 	 * rt, 0x0243; DMFC2 rt, 0x0244; DMFC2 rt, 0x0245; DMFC2 rt,
188 	 * 0x0246; DMFC2 rt, 0x0247; DMFC2 rt, 0x0248; DMFC2 rt,
189 	 * 0x0249; DMFC2 rt, 0x024A; DMFC2 rt, 0x024B; DMFC2 rt,
190 	 * 0x024C; DMFC2 rt, 0x024D; DMFC2 rt, 0x024E - Pass2 */
191 	unsigned long	cop2_hsh_datw[15];
192 	/* DMFC2 rt, 0x0250; DMFC2 rt, 0x0251; DMFC2 rt, 0x0252; DMFC2
193 	 * rt, 0x0253; DMFC2 rt, 0x0254; DMFC2 rt, 0x0255; DMFC2 rt,
194 	 * 0x0256; DMFC2 rt, 0x0257 - Pass2 */
195 	unsigned long	cop2_hsh_ivw[8];
196 	/* DMFC2 rt, 0x0258; DMFC2 rt, 0x0259 - Pass2 */
197 	unsigned long	cop2_gfm_mult[2];
198 	/* DMFC2 rt, 0x025E - Pass2 */
199 	unsigned long	cop2_gfm_poly;
200 	/* DMFC2 rt, 0x025A; DMFC2 rt, 0x025B - Pass2 */
201 	unsigned long	cop2_gfm_result[2];
202 	/* DMFC2 rt, 0x24F, DMFC2 rt, 0x50, OCTEON III */
203 	unsigned long	cop2_sha3[2];
204 };
205 #define COP2_INIT						\
206 	.cp2			= {0,},
207 
208 struct octeon_cvmseg_state {
209 	unsigned long cvmseg[CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE]
210 			    [cpu_dcache_line_size() / sizeof(unsigned long)];
211 };
212 
213 #elif defined(CONFIG_CPU_XLP)
214 struct nlm_cop2_state {
215 	u64	rx[4];
216 	u64	tx[4];
217 	u32	tx_msg_status;
218 	u32	rx_msg_status;
219 };
220 
221 #define COP2_INIT						\
222 	.cp2			= {{0}, {0}, 0, 0},
223 #else
224 #define COP2_INIT
225 #endif
226 
227 typedef struct {
228 	unsigned long seg;
229 } mm_segment_t;
230 
231 #ifdef CONFIG_CPU_HAS_MSA
232 # define ARCH_MIN_TASKALIGN	16
233 # define FPU_ALIGN		__aligned(16)
234 #else
235 # define ARCH_MIN_TASKALIGN	8
236 # define FPU_ALIGN
237 #endif
238 
239 struct mips_abi;
240 
241 /*
242  * If you change thread_struct remember to change the #defines below too!
243  */
244 struct thread_struct {
245 	/* Saved main processor registers. */
246 	unsigned long reg16;
247 	unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
248 	unsigned long reg29, reg30, reg31;
249 
250 	/* Saved cp0 stuff. */
251 	unsigned long cp0_status;
252 
253 #ifdef CONFIG_MIPS_FP_SUPPORT
254 	/* Saved fpu/fpu emulator stuff. */
255 	struct mips_fpu_struct fpu FPU_ALIGN;
256 #endif
257 	/* Assigned branch delay slot 'emulation' frame */
258 	atomic_t bd_emu_frame;
259 	/* PC of the branch from a branch delay slot 'emulation' */
260 	unsigned long bd_emu_branch_pc;
261 	/* PC to continue from following a branch delay slot 'emulation' */
262 	unsigned long bd_emu_cont_pc;
263 #ifdef CONFIG_MIPS_MT_FPAFF
264 	/* Emulated instruction count */
265 	unsigned long emulated_fp;
266 	/* Saved per-thread scheduler affinity mask */
267 	cpumask_t user_cpus_allowed;
268 #endif /* CONFIG_MIPS_MT_FPAFF */
269 
270 	/* Saved state of the DSP ASE, if available. */
271 	struct mips_dsp_state dsp;
272 
273 	/* Saved watch register state, if available. */
274 	union mips_watch_reg_state watch;
275 
276 	/* Other stuff associated with the thread. */
277 	unsigned long cp0_badvaddr;	/* Last user fault */
278 	unsigned long cp0_baduaddr;	/* Last kernel fault accessing USEG */
279 	unsigned long error_code;
280 	unsigned long trap_nr;
281 #ifdef CONFIG_CPU_CAVIUM_OCTEON
282 	struct octeon_cop2_state cp2 __attribute__ ((__aligned__(128)));
283 	struct octeon_cvmseg_state cvmseg __attribute__ ((__aligned__(128)));
284 #endif
285 #ifdef CONFIG_CPU_XLP
286 	struct nlm_cop2_state cp2;
287 #endif
288 	struct mips_abi *abi;
289 };
290 
291 #ifdef CONFIG_MIPS_MT_FPAFF
292 #define FPAFF_INIT						\
293 	.emulated_fp			= 0,			\
294 	.user_cpus_allowed		= INIT_CPUMASK,
295 #else
296 #define FPAFF_INIT
297 #endif /* CONFIG_MIPS_MT_FPAFF */
298 
299 #ifdef CONFIG_MIPS_FP_SUPPORT
300 # define FPU_INIT						\
301 	.fpu			= {				\
302 		.fpr		= {{{0,},},},			\
303 		.fcr31		= 0,				\
304 		.msacsr		= 0,				\
305 	},
306 #else
307 # define FPU_INIT
308 #endif
309 
310 #define INIT_THREAD  {						\
311 	/*							\
312 	 * Saved main processor registers			\
313 	 */							\
314 	.reg16			= 0,				\
315 	.reg17			= 0,				\
316 	.reg18			= 0,				\
317 	.reg19			= 0,				\
318 	.reg20			= 0,				\
319 	.reg21			= 0,				\
320 	.reg22			= 0,				\
321 	.reg23			= 0,				\
322 	.reg29			= 0,				\
323 	.reg30			= 0,				\
324 	.reg31			= 0,				\
325 	/*							\
326 	 * Saved cp0 stuff					\
327 	 */							\
328 	.cp0_status		= 0,				\
329 	/*							\
330 	 * Saved FPU/FPU emulator stuff				\
331 	 */							\
332 	FPU_INIT						\
333 	/*							\
334 	 * FPU affinity state (null if not FPAFF)		\
335 	 */							\
336 	FPAFF_INIT						\
337 	/* Delay slot emulation */				\
338 	.bd_emu_frame = ATOMIC_INIT(BD_EMUFRAME_NONE),		\
339 	.bd_emu_branch_pc = 0,					\
340 	.bd_emu_cont_pc = 0,					\
341 	/*							\
342 	 * Saved DSP stuff					\
343 	 */							\
344 	.dsp			= {				\
345 		.dspr		= {0, },			\
346 		.dspcontrol	= 0,				\
347 	},							\
348 	/*							\
349 	 * saved watch register stuff				\
350 	 */							\
351 	.watch = {{{0,},},},					\
352 	/*							\
353 	 * Other stuff associated with the process		\
354 	 */							\
355 	.cp0_badvaddr		= 0,				\
356 	.cp0_baduaddr		= 0,				\
357 	.error_code		= 0,				\
358 	.trap_nr		= 0,				\
359 	/*							\
360 	 * Platform specific cop2 registers(null if no COP2)	\
361 	 */							\
362 	COP2_INIT						\
363 }
364 
365 struct task_struct;
366 
367 /* Free all resources held by a thread. */
368 #define release_thread(thread) do { } while(0)
369 
370 /*
371  * Do necessary setup to start up a newly executed thread.
372  */
373 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
374 
375 static inline void flush_thread(void)
376 {
377 }
378 
379 unsigned long get_wchan(struct task_struct *p);
380 
381 #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
382 			 THREAD_SIZE - 32 - sizeof(struct pt_regs))
383 #define task_pt_regs(tsk) ((struct pt_regs *)__KSTK_TOS(tsk))
384 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->cp0_epc)
385 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[29])
386 #define KSTK_STATUS(tsk) (task_pt_regs(tsk)->cp0_status)
387 
388 #ifdef CONFIG_CPU_LOONGSON64
389 /*
390  * Loongson-3's SFB (Store-Fill-Buffer) may buffer writes indefinitely when a
391  * tight read loop is executed, because reads take priority over writes & the
392  * hardware (incorrectly) doesn't ensure that writes will eventually occur.
393  *
394  * Since spin loops of any kind should have a cpu_relax() in them, force an SFB
395  * flush from cpu_relax() such that any pending writes will become visible as
396  * expected.
397  */
398 #define cpu_relax()	smp_mb()
399 #else
400 #define cpu_relax()	barrier()
401 #endif
402 
403 /*
404  * Return_address is a replacement for __builtin_return_address(count)
405  * which on certain architectures cannot reasonably be implemented in GCC
406  * (MIPS, Alpha) or is unusable with -fomit-frame-pointer (i386).
407  * Note that __builtin_return_address(x>=1) is forbidden because GCC
408  * aborts compilation on some CPUs.  It's simply not possible to unwind
409  * some CPU's stackframes.
410  *
411  * __builtin_return_address works only for non-leaf functions.	We avoid the
412  * overhead of a function call by forcing the compiler to save the return
413  * address register on the stack.
414  */
415 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
416 
417 #ifdef CONFIG_CPU_HAS_PREFETCH
418 
419 #define ARCH_HAS_PREFETCH
420 #define prefetch(x) __builtin_prefetch((x), 0, 1)
421 
422 #define ARCH_HAS_PREFETCHW
423 #define prefetchw(x) __builtin_prefetch((x), 1, 1)
424 
425 #endif
426 
427 /*
428  * Functions & macros implementing the PR_GET_FP_MODE & PR_SET_FP_MODE options
429  * to the prctl syscall.
430  */
431 extern int mips_get_process_fp_mode(struct task_struct *task);
432 extern int mips_set_process_fp_mode(struct task_struct *task,
433 				    unsigned int value);
434 
435 #define GET_FP_MODE(task)		mips_get_process_fp_mode(task)
436 #define SET_FP_MODE(task,value)		mips_set_process_fp_mode(task, value)
437 
438 #endif /* _ASM_PROCESSOR_H */
439