xref: /openbmc/linux/arch/mips/include/asm/processor.h (revision ac8b6f14)
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 /*
33  * MIPS does have an arch_pick_mmap_layout()
34  */
35 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
36 
37 #ifdef CONFIG_32BIT
38 #ifdef CONFIG_KVM_GUEST
39 /* User space process size is limited to 1GB in KVM Guest Mode */
40 #define TASK_SIZE	0x3fff8000UL
41 #else
42 /*
43  * User space process size: 2GB. This is hardcoded into a few places,
44  * so don't change it unless you know what you are doing.
45  */
46 #define TASK_SIZE	0x80000000UL
47 #endif
48 
49 #define STACK_TOP_MAX	TASK_SIZE
50 
51 #define TASK_IS_32BIT_ADDR 1
52 
53 #endif
54 
55 #ifdef CONFIG_64BIT
56 /*
57  * User space process size: 1TB. This is hardcoded into a few places,
58  * so don't change it unless you know what you are doing.  TASK_SIZE
59  * is limited to 1TB by the R4000 architecture; R10000 and better can
60  * support 16TB; the architectural reserve for future expansion is
61  * 8192EB ...
62  */
63 #define TASK_SIZE32	0x7fff8000UL
64 #ifdef CONFIG_MIPS_VA_BITS_48
65 #define TASK_SIZE64     (0x1UL << ((cpu_data[0].vmbits>48)?48:cpu_data[0].vmbits))
66 #else
67 #define TASK_SIZE64     0x10000000000UL
68 #endif
69 #define TASK_SIZE (test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
70 #define STACK_TOP_MAX	TASK_SIZE64
71 
72 #define TASK_SIZE_OF(tsk)						\
73 	(test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
74 
75 #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR)
76 
77 #endif
78 
79 #define VDSO_RANDOMIZE_SIZE	(TASK_IS_32BIT_ADDR ? SZ_1M : SZ_64M)
80 
81 extern unsigned long mips_stack_top(void);
82 #define STACK_TOP		mips_stack_top()
83 
84 /*
85  * This decides where the kernel will search for a free chunk of vm
86  * space during mmap's.
87  */
88 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
89 
90 
91 #define NUM_FPU_REGS	32
92 
93 #ifdef CONFIG_CPU_HAS_MSA
94 # define FPU_REG_WIDTH	128
95 #else
96 # define FPU_REG_WIDTH	64
97 #endif
98 
99 union fpureg {
100 	__u32	val32[FPU_REG_WIDTH / 32];
101 	__u64	val64[FPU_REG_WIDTH / 64];
102 };
103 
104 #ifdef CONFIG_CPU_LITTLE_ENDIAN
105 # define FPR_IDX(width, idx)	(idx)
106 #else
107 # define FPR_IDX(width, idx)	((idx) ^ ((64 / (width)) - 1))
108 #endif
109 
110 #define BUILD_FPR_ACCESS(width) \
111 static inline u##width get_fpr##width(union fpureg *fpr, unsigned idx)	\
112 {									\
113 	return fpr->val##width[FPR_IDX(width, idx)];			\
114 }									\
115 									\
116 static inline void set_fpr##width(union fpureg *fpr, unsigned idx,	\
117 				  u##width val)				\
118 {									\
119 	fpr->val##width[FPR_IDX(width, idx)] = val;			\
120 }
121 
122 BUILD_FPR_ACCESS(32)
123 BUILD_FPR_ACCESS(64)
124 
125 /*
126  * It would be nice to add some more fields for emulator statistics,
127  * the additional information is private to the FPU emulator for now.
128  * See arch/mips/include/asm/fpu_emulator.h.
129  */
130 
131 struct mips_fpu_struct {
132 	union fpureg	fpr[NUM_FPU_REGS];
133 	unsigned int	fcr31;
134 	unsigned int	msacsr;
135 };
136 
137 #define NUM_DSP_REGS   6
138 
139 typedef unsigned long dspreg_t;
140 
141 struct mips_dsp_state {
142 	dspreg_t	dspr[NUM_DSP_REGS];
143 	unsigned int	dspcontrol;
144 };
145 
146 #define INIT_CPUMASK { \
147 	{0,} \
148 }
149 
150 struct mips3264_watch_reg_state {
151 	/* The width of watchlo is 32 in a 32 bit kernel and 64 in a
152 	   64 bit kernel.  We use unsigned long as it has the same
153 	   property. */
154 	unsigned long watchlo[NUM_WATCH_REGS];
155 	/* Only the mask and IRW bits from watchhi. */
156 	u16 watchhi[NUM_WATCH_REGS];
157 };
158 
159 union mips_watch_reg_state {
160 	struct mips3264_watch_reg_state mips3264;
161 };
162 
163 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
164 
165 struct octeon_cop2_state {
166 	/* DMFC2 rt, 0x0201 */
167 	unsigned long	cop2_crc_iv;
168 	/* DMFC2 rt, 0x0202 (Set with DMTC2 rt, 0x1202) */
169 	unsigned long	cop2_crc_length;
170 	/* DMFC2 rt, 0x0200 (set with DMTC2 rt, 0x4200) */
171 	unsigned long	cop2_crc_poly;
172 	/* DMFC2 rt, 0x0402; DMFC2 rt, 0x040A */
173 	unsigned long	cop2_llm_dat[2];
174        /* DMFC2 rt, 0x0084 */
175 	unsigned long	cop2_3des_iv;
176 	/* DMFC2 rt, 0x0080; DMFC2 rt, 0x0081; DMFC2 rt, 0x0082 */
177 	unsigned long	cop2_3des_key[3];
178 	/* DMFC2 rt, 0x0088 (Set with DMTC2 rt, 0x0098) */
179 	unsigned long	cop2_3des_result;
180 	/* DMFC2 rt, 0x0111 (FIXME: Read Pass1 Errata) */
181 	unsigned long	cop2_aes_inp0;
182 	/* DMFC2 rt, 0x0102; DMFC2 rt, 0x0103 */
183 	unsigned long	cop2_aes_iv[2];
184 	/* DMFC2 rt, 0x0104; DMFC2 rt, 0x0105; DMFC2 rt, 0x0106; DMFC2
185 	 * rt, 0x0107 */
186 	unsigned long	cop2_aes_key[4];
187 	/* DMFC2 rt, 0x0110 */
188 	unsigned long	cop2_aes_keylen;
189 	/* DMFC2 rt, 0x0100; DMFC2 rt, 0x0101 */
190 	unsigned long	cop2_aes_result[2];
191 	/* DMFC2 rt, 0x0240; DMFC2 rt, 0x0241; DMFC2 rt, 0x0242; DMFC2
192 	 * rt, 0x0243; DMFC2 rt, 0x0244; DMFC2 rt, 0x0245; DMFC2 rt,
193 	 * 0x0246; DMFC2 rt, 0x0247; DMFC2 rt, 0x0248; DMFC2 rt,
194 	 * 0x0249; DMFC2 rt, 0x024A; DMFC2 rt, 0x024B; DMFC2 rt,
195 	 * 0x024C; DMFC2 rt, 0x024D; DMFC2 rt, 0x024E - Pass2 */
196 	unsigned long	cop2_hsh_datw[15];
197 	/* DMFC2 rt, 0x0250; DMFC2 rt, 0x0251; DMFC2 rt, 0x0252; DMFC2
198 	 * rt, 0x0253; DMFC2 rt, 0x0254; DMFC2 rt, 0x0255; DMFC2 rt,
199 	 * 0x0256; DMFC2 rt, 0x0257 - Pass2 */
200 	unsigned long	cop2_hsh_ivw[8];
201 	/* DMFC2 rt, 0x0258; DMFC2 rt, 0x0259 - Pass2 */
202 	unsigned long	cop2_gfm_mult[2];
203 	/* DMFC2 rt, 0x025E - Pass2 */
204 	unsigned long	cop2_gfm_poly;
205 	/* DMFC2 rt, 0x025A; DMFC2 rt, 0x025B - Pass2 */
206 	unsigned long	cop2_gfm_result[2];
207 	/* DMFC2 rt, 0x24F, DMFC2 rt, 0x50, OCTEON III */
208 	unsigned long	cop2_sha3[2];
209 };
210 #define COP2_INIT						\
211 	.cp2			= {0,},
212 
213 struct octeon_cvmseg_state {
214 	unsigned long cvmseg[CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE]
215 			    [cpu_dcache_line_size() / sizeof(unsigned long)];
216 };
217 
218 #elif defined(CONFIG_CPU_XLP)
219 struct nlm_cop2_state {
220 	u64	rx[4];
221 	u64	tx[4];
222 	u32	tx_msg_status;
223 	u32	rx_msg_status;
224 };
225 
226 #define COP2_INIT						\
227 	.cp2			= {{0}, {0}, 0, 0},
228 #else
229 #define COP2_INIT
230 #endif
231 
232 typedef struct {
233 	unsigned long seg;
234 } mm_segment_t;
235 
236 #ifdef CONFIG_CPU_HAS_MSA
237 # define ARCH_MIN_TASKALIGN	16
238 # define FPU_ALIGN		__aligned(16)
239 #else
240 # define ARCH_MIN_TASKALIGN	8
241 # define FPU_ALIGN
242 #endif
243 
244 struct mips_abi;
245 
246 /*
247  * If you change thread_struct remember to change the #defines below too!
248  */
249 struct thread_struct {
250 	/* Saved main processor registers. */
251 	unsigned long reg16;
252 	unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
253 	unsigned long reg29, reg30, reg31;
254 
255 	/* Saved cp0 stuff. */
256 	unsigned long cp0_status;
257 
258 	/* Saved fpu/fpu emulator stuff. */
259 	struct mips_fpu_struct fpu FPU_ALIGN;
260 	/* Assigned branch delay slot 'emulation' frame */
261 	atomic_t bd_emu_frame;
262 	/* PC of the branch from a branch delay slot 'emulation' */
263 	unsigned long bd_emu_branch_pc;
264 	/* PC to continue from following a branch delay slot 'emulation' */
265 	unsigned long bd_emu_cont_pc;
266 #ifdef CONFIG_MIPS_MT_FPAFF
267 	/* Emulated instruction count */
268 	unsigned long emulated_fp;
269 	/* Saved per-thread scheduler affinity mask */
270 	cpumask_t user_cpus_allowed;
271 #endif /* CONFIG_MIPS_MT_FPAFF */
272 
273 	/* Saved state of the DSP ASE, if available. */
274 	struct mips_dsp_state dsp;
275 
276 	/* Saved watch register state, if available. */
277 	union mips_watch_reg_state watch;
278 
279 	/* Other stuff associated with the thread. */
280 	unsigned long cp0_badvaddr;	/* Last user fault */
281 	unsigned long cp0_baduaddr;	/* Last kernel fault accessing USEG */
282 	unsigned long error_code;
283 	unsigned long trap_nr;
284 #ifdef CONFIG_CPU_CAVIUM_OCTEON
285 	struct octeon_cop2_state cp2 __attribute__ ((__aligned__(128)));
286 	struct octeon_cvmseg_state cvmseg __attribute__ ((__aligned__(128)));
287 #endif
288 #ifdef CONFIG_CPU_XLP
289 	struct nlm_cop2_state cp2;
290 #endif
291 	struct mips_abi *abi;
292 };
293 
294 #ifdef CONFIG_MIPS_MT_FPAFF
295 #define FPAFF_INIT						\
296 	.emulated_fp			= 0,			\
297 	.user_cpus_allowed		= INIT_CPUMASK,
298 #else
299 #define FPAFF_INIT
300 #endif /* CONFIG_MIPS_MT_FPAFF */
301 
302 #define INIT_THREAD  {						\
303 	/*							\
304 	 * Saved main processor registers			\
305 	 */							\
306 	.reg16			= 0,				\
307 	.reg17			= 0,				\
308 	.reg18			= 0,				\
309 	.reg19			= 0,				\
310 	.reg20			= 0,				\
311 	.reg21			= 0,				\
312 	.reg22			= 0,				\
313 	.reg23			= 0,				\
314 	.reg29			= 0,				\
315 	.reg30			= 0,				\
316 	.reg31			= 0,				\
317 	/*							\
318 	 * Saved cp0 stuff					\
319 	 */							\
320 	.cp0_status		= 0,				\
321 	/*							\
322 	 * Saved FPU/FPU emulator stuff				\
323 	 */							\
324 	.fpu			= {				\
325 		.fpr		= {{{0,},},},			\
326 		.fcr31		= 0,				\
327 		.msacsr		= 0,				\
328 	},							\
329 	/*							\
330 	 * FPU affinity state (null if not FPAFF)		\
331 	 */							\
332 	FPAFF_INIT						\
333 	/* Delay slot emulation */				\
334 	.bd_emu_frame = ATOMIC_INIT(BD_EMUFRAME_NONE),		\
335 	.bd_emu_branch_pc = 0,					\
336 	.bd_emu_cont_pc = 0,					\
337 	/*							\
338 	 * Saved DSP stuff					\
339 	 */							\
340 	.dsp			= {				\
341 		.dspr		= {0, },			\
342 		.dspcontrol	= 0,				\
343 	},							\
344 	/*							\
345 	 * saved watch register stuff				\
346 	 */							\
347 	.watch = {{{0,},},},					\
348 	/*							\
349 	 * Other stuff associated with the process		\
350 	 */							\
351 	.cp0_badvaddr		= 0,				\
352 	.cp0_baduaddr		= 0,				\
353 	.error_code		= 0,				\
354 	.trap_nr		= 0,				\
355 	/*							\
356 	 * Platform specific cop2 registers(null if no COP2)	\
357 	 */							\
358 	COP2_INIT						\
359 }
360 
361 struct task_struct;
362 
363 /* Free all resources held by a thread. */
364 #define release_thread(thread) do { } while(0)
365 
366 /*
367  * Do necessary setup to start up a newly executed thread.
368  */
369 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
370 
371 static inline void flush_thread(void)
372 {
373 }
374 
375 unsigned long get_wchan(struct task_struct *p);
376 
377 #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
378 			 THREAD_SIZE - 32 - sizeof(struct pt_regs))
379 #define task_pt_regs(tsk) ((struct pt_regs *)__KSTK_TOS(tsk))
380 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->cp0_epc)
381 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[29])
382 #define KSTK_STATUS(tsk) (task_pt_regs(tsk)->cp0_status)
383 
384 #ifdef CONFIG_CPU_LOONGSON3
385 /*
386  * Loongson-3's SFB (Store-Fill-Buffer) may buffer writes indefinitely when a
387  * tight read loop is executed, because reads take priority over writes & the
388  * hardware (incorrectly) doesn't ensure that writes will eventually occur.
389  *
390  * Since spin loops of any kind should have a cpu_relax() in them, force an SFB
391  * flush from cpu_relax() such that any pending writes will become visible as
392  * expected.
393  */
394 #define cpu_relax()	smp_mb()
395 #else
396 #define cpu_relax()	barrier()
397 #endif
398 
399 /*
400  * Return_address is a replacement for __builtin_return_address(count)
401  * which on certain architectures cannot reasonably be implemented in GCC
402  * (MIPS, Alpha) or is unusable with -fomit-frame-pointer (i386).
403  * Note that __builtin_return_address(x>=1) is forbidden because GCC
404  * aborts compilation on some CPUs.  It's simply not possible to unwind
405  * some CPU's stackframes.
406  *
407  * __builtin_return_address works only for non-leaf functions.	We avoid the
408  * overhead of a function call by forcing the compiler to save the return
409  * address register on the stack.
410  */
411 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
412 
413 #ifdef CONFIG_CPU_HAS_PREFETCH
414 
415 #define ARCH_HAS_PREFETCH
416 #define prefetch(x) __builtin_prefetch((x), 0, 1)
417 
418 #define ARCH_HAS_PREFETCHW
419 #define prefetchw(x) __builtin_prefetch((x), 1, 1)
420 
421 #endif
422 
423 /*
424  * Functions & macros implementing the PR_GET_FP_MODE & PR_SET_FP_MODE options
425  * to the prctl syscall.
426  */
427 extern int mips_get_process_fp_mode(struct task_struct *task);
428 extern int mips_set_process_fp_mode(struct task_struct *task,
429 				    unsigned int value);
430 
431 #define GET_FP_MODE(task)		mips_get_process_fp_mode(task)
432 #define SET_FP_MODE(task,value)		mips_set_process_fp_mode(task, value)
433 
434 #endif /* _ASM_PROCESSOR_H */
435