xref: /openbmc/linux/arch/mips/include/asm/processor.h (revision afb46f79)
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/cpumask.h>
15 #include <linux/threads.h>
16 
17 #include <asm/cachectl.h>
18 #include <asm/cpu.h>
19 #include <asm/cpu-info.h>
20 #include <asm/mipsregs.h>
21 #include <asm/prefetch.h>
22 
23 /*
24  * Return current * instruction pointer ("program counter").
25  */
26 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
27 
28 /*
29  * System setup and hardware flags..
30  */
31 
32 extern unsigned int vced_count, vcei_count;
33 
34 /*
35  * MIPS does have an arch_pick_mmap_layout()
36  */
37 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
38 
39 /*
40  * A special page (the vdso) is mapped into all processes at the very
41  * top of the virtual memory space.
42  */
43 #define SPECIAL_PAGES_SIZE PAGE_SIZE
44 
45 #ifdef CONFIG_32BIT
46 #ifdef CONFIG_KVM_GUEST
47 /* User space process size is limited to 1GB in KVM Guest Mode */
48 #define TASK_SIZE	0x3fff8000UL
49 #else
50 /*
51  * User space process size: 2GB. This is hardcoded into a few places,
52  * so don't change it unless you know what you are doing.
53  */
54 #define TASK_SIZE	0x7fff8000UL
55 #endif
56 
57 #ifdef __KERNEL__
58 #define STACK_TOP_MAX	TASK_SIZE
59 #endif
60 
61 #define TASK_IS_32BIT_ADDR 1
62 
63 #endif
64 
65 #ifdef CONFIG_64BIT
66 /*
67  * User space process size: 1TB. This is hardcoded into a few places,
68  * so don't change it unless you know what you are doing.  TASK_SIZE
69  * is limited to 1TB by the R4000 architecture; R10000 and better can
70  * support 16TB; the architectural reserve for future expansion is
71  * 8192EB ...
72  */
73 #define TASK_SIZE32	0x7fff8000UL
74 #define TASK_SIZE64	0x10000000000UL
75 #define TASK_SIZE (test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
76 
77 #ifdef __KERNEL__
78 #define STACK_TOP_MAX	TASK_SIZE64
79 #endif
80 
81 
82 #define TASK_SIZE_OF(tsk)						\
83 	(test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
84 
85 #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR)
86 
87 #endif
88 
89 #define STACK_TOP	((TASK_SIZE & PAGE_MASK) - SPECIAL_PAGES_SIZE)
90 
91 /*
92  * This decides where the kernel will search for a free chunk of vm
93  * space during mmap's.
94  */
95 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
96 
97 
98 #define NUM_FPU_REGS	32
99 
100 #ifdef CONFIG_CPU_HAS_MSA
101 # define FPU_REG_WIDTH	128
102 #else
103 # define FPU_REG_WIDTH	64
104 #endif
105 
106 union fpureg {
107 	__u32	val32[FPU_REG_WIDTH / 32];
108 	__u64	val64[FPU_REG_WIDTH / 64];
109 };
110 
111 #ifdef CONFIG_CPU_LITTLE_ENDIAN
112 # define FPR_IDX(width, idx)	(idx)
113 #else
114 # define FPR_IDX(width, idx)	((FPU_REG_WIDTH / (width)) - 1 - (idx))
115 #endif
116 
117 #define BUILD_FPR_ACCESS(width) \
118 static inline u##width get_fpr##width(union fpureg *fpr, unsigned idx)	\
119 {									\
120 	return fpr->val##width[FPR_IDX(width, idx)];			\
121 }									\
122 									\
123 static inline void set_fpr##width(union fpureg *fpr, unsigned idx,	\
124 				  u##width val)				\
125 {									\
126 	fpr->val##width[FPR_IDX(width, idx)] = val;			\
127 }
128 
129 BUILD_FPR_ACCESS(32)
130 BUILD_FPR_ACCESS(64)
131 
132 /*
133  * It would be nice to add some more fields for emulator statistics,
134  * the additional information is private to the FPU emulator for now.
135  * See arch/mips/include/asm/fpu_emulator.h.
136  */
137 
138 struct mips_fpu_struct {
139 	union fpureg	fpr[NUM_FPU_REGS];
140 	unsigned int	fcr31;
141 	unsigned int	msacsr;
142 };
143 
144 #define NUM_DSP_REGS   6
145 
146 typedef __u32 dspreg_t;
147 
148 struct mips_dsp_state {
149 	dspreg_t	dspr[NUM_DSP_REGS];
150 	unsigned int	dspcontrol;
151 };
152 
153 #define INIT_CPUMASK { \
154 	{0,} \
155 }
156 
157 struct mips3264_watch_reg_state {
158 	/* The width of watchlo is 32 in a 32 bit kernel and 64 in a
159 	   64 bit kernel.  We use unsigned long as it has the same
160 	   property. */
161 	unsigned long watchlo[NUM_WATCH_REGS];
162 	/* Only the mask and IRW bits from watchhi. */
163 	u16 watchhi[NUM_WATCH_REGS];
164 };
165 
166 union mips_watch_reg_state {
167 	struct mips3264_watch_reg_state mips3264;
168 };
169 
170 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
171 
172 struct octeon_cop2_state {
173 	/* DMFC2 rt, 0x0201 */
174 	unsigned long	cop2_crc_iv;
175 	/* DMFC2 rt, 0x0202 (Set with DMTC2 rt, 0x1202) */
176 	unsigned long	cop2_crc_length;
177 	/* DMFC2 rt, 0x0200 (set with DMTC2 rt, 0x4200) */
178 	unsigned long	cop2_crc_poly;
179 	/* DMFC2 rt, 0x0402; DMFC2 rt, 0x040A */
180 	unsigned long	cop2_llm_dat[2];
181        /* DMFC2 rt, 0x0084 */
182 	unsigned long	cop2_3des_iv;
183 	/* DMFC2 rt, 0x0080; DMFC2 rt, 0x0081; DMFC2 rt, 0x0082 */
184 	unsigned long	cop2_3des_key[3];
185 	/* DMFC2 rt, 0x0088 (Set with DMTC2 rt, 0x0098) */
186 	unsigned long	cop2_3des_result;
187 	/* DMFC2 rt, 0x0111 (FIXME: Read Pass1 Errata) */
188 	unsigned long	cop2_aes_inp0;
189 	/* DMFC2 rt, 0x0102; DMFC2 rt, 0x0103 */
190 	unsigned long	cop2_aes_iv[2];
191 	/* DMFC2 rt, 0x0104; DMFC2 rt, 0x0105; DMFC2 rt, 0x0106; DMFC2
192 	 * rt, 0x0107 */
193 	unsigned long	cop2_aes_key[4];
194 	/* DMFC2 rt, 0x0110 */
195 	unsigned long	cop2_aes_keylen;
196 	/* DMFC2 rt, 0x0100; DMFC2 rt, 0x0101 */
197 	unsigned long	cop2_aes_result[2];
198 	/* DMFC2 rt, 0x0240; DMFC2 rt, 0x0241; DMFC2 rt, 0x0242; DMFC2
199 	 * rt, 0x0243; DMFC2 rt, 0x0244; DMFC2 rt, 0x0245; DMFC2 rt,
200 	 * 0x0246; DMFC2 rt, 0x0247; DMFC2 rt, 0x0248; DMFC2 rt,
201 	 * 0x0249; DMFC2 rt, 0x024A; DMFC2 rt, 0x024B; DMFC2 rt,
202 	 * 0x024C; DMFC2 rt, 0x024D; DMFC2 rt, 0x024E - Pass2 */
203 	unsigned long	cop2_hsh_datw[15];
204 	/* DMFC2 rt, 0x0250; DMFC2 rt, 0x0251; DMFC2 rt, 0x0252; DMFC2
205 	 * rt, 0x0253; DMFC2 rt, 0x0254; DMFC2 rt, 0x0255; DMFC2 rt,
206 	 * 0x0256; DMFC2 rt, 0x0257 - Pass2 */
207 	unsigned long	cop2_hsh_ivw[8];
208 	/* DMFC2 rt, 0x0258; DMFC2 rt, 0x0259 - Pass2 */
209 	unsigned long	cop2_gfm_mult[2];
210 	/* DMFC2 rt, 0x025E - Pass2 */
211 	unsigned long	cop2_gfm_poly;
212 	/* DMFC2 rt, 0x025A; DMFC2 rt, 0x025B - Pass2 */
213 	unsigned long	cop2_gfm_result[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 #define ARCH_MIN_TASKALIGN	8
242 
243 struct mips_abi;
244 
245 /*
246  * If you change thread_struct remember to change the #defines below too!
247  */
248 struct thread_struct {
249 	/* Saved main processor registers. */
250 	unsigned long reg16;
251 	unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
252 	unsigned long reg29, reg30, reg31;
253 
254 	/* Saved cp0 stuff. */
255 	unsigned long cp0_status;
256 
257 	/* Saved fpu/fpu emulator stuff. */
258 	struct mips_fpu_struct fpu;
259 #ifdef CONFIG_MIPS_MT_FPAFF
260 	/* Emulated instruction count */
261 	unsigned long emulated_fp;
262 	/* Saved per-thread scheduler affinity mask */
263 	cpumask_t user_cpus_allowed;
264 #endif /* CONFIG_MIPS_MT_FPAFF */
265 
266 	/* Saved state of the DSP ASE, if available. */
267 	struct mips_dsp_state dsp;
268 
269 	/* Saved watch register state, if available. */
270 	union mips_watch_reg_state watch;
271 
272 	/* Other stuff associated with the thread. */
273 	unsigned long cp0_badvaddr;	/* Last user fault */
274 	unsigned long cp0_baduaddr;	/* Last kernel fault accessing USEG */
275 	unsigned long error_code;
276 #ifdef CONFIG_CPU_CAVIUM_OCTEON
277 	struct octeon_cop2_state cp2 __attribute__ ((__aligned__(128)));
278 	struct octeon_cvmseg_state cvmseg __attribute__ ((__aligned__(128)));
279 #endif
280 #ifdef CONFIG_CPU_XLP
281 	struct nlm_cop2_state cp2;
282 #endif
283 	struct mips_abi *abi;
284 };
285 
286 #ifdef CONFIG_MIPS_MT_FPAFF
287 #define FPAFF_INIT						\
288 	.emulated_fp			= 0,			\
289 	.user_cpus_allowed		= INIT_CPUMASK,
290 #else
291 #define FPAFF_INIT
292 #endif /* CONFIG_MIPS_MT_FPAFF */
293 
294 #define INIT_THREAD  {						\
295 	/*							\
296 	 * Saved main processor registers			\
297 	 */							\
298 	.reg16			= 0,				\
299 	.reg17			= 0,				\
300 	.reg18			= 0,				\
301 	.reg19			= 0,				\
302 	.reg20			= 0,				\
303 	.reg21			= 0,				\
304 	.reg22			= 0,				\
305 	.reg23			= 0,				\
306 	.reg29			= 0,				\
307 	.reg30			= 0,				\
308 	.reg31			= 0,				\
309 	/*							\
310 	 * Saved cp0 stuff					\
311 	 */							\
312 	.cp0_status		= 0,				\
313 	/*							\
314 	 * Saved FPU/FPU emulator stuff				\
315 	 */							\
316 	.fpu			= {				\
317 		.fpr		= {{{0,},},},			\
318 		.fcr31		= 0,				\
319 		.msacsr		= 0,				\
320 	},							\
321 	/*							\
322 	 * FPU affinity state (null if not FPAFF)		\
323 	 */							\
324 	FPAFF_INIT						\
325 	/*							\
326 	 * Saved DSP stuff					\
327 	 */							\
328 	.dsp			= {				\
329 		.dspr		= {0, },			\
330 		.dspcontrol	= 0,				\
331 	},							\
332 	/*							\
333 	 * saved watch register stuff				\
334 	 */							\
335 	.watch = {{{0,},},},					\
336 	/*							\
337 	 * Other stuff associated with the process		\
338 	 */							\
339 	.cp0_badvaddr		= 0,				\
340 	.cp0_baduaddr		= 0,				\
341 	.error_code		= 0,				\
342 	/*							\
343 	 * Platform specific cop2 registers(null if no COP2)	\
344 	 */							\
345 	COP2_INIT						\
346 }
347 
348 struct task_struct;
349 
350 /* Free all resources held by a thread. */
351 #define release_thread(thread) do { } while(0)
352 
353 extern unsigned long thread_saved_pc(struct task_struct *tsk);
354 
355 /*
356  * Do necessary setup to start up a newly executed thread.
357  */
358 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
359 
360 unsigned long get_wchan(struct task_struct *p);
361 
362 #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
363 			 THREAD_SIZE - 32 - sizeof(struct pt_regs))
364 #define task_pt_regs(tsk) ((struct pt_regs *)__KSTK_TOS(tsk))
365 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->cp0_epc)
366 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[29])
367 #define KSTK_STATUS(tsk) (task_pt_regs(tsk)->cp0_status)
368 
369 #define cpu_relax()	barrier()
370 
371 /*
372  * Return_address is a replacement for __builtin_return_address(count)
373  * which on certain architectures cannot reasonably be implemented in GCC
374  * (MIPS, Alpha) or is unusable with -fomit-frame-pointer (i386).
375  * Note that __builtin_return_address(x>=1) is forbidden because GCC
376  * aborts compilation on some CPUs.  It's simply not possible to unwind
377  * some CPU's stackframes.
378  *
379  * __builtin_return_address works only for non-leaf functions.	We avoid the
380  * overhead of a function call by forcing the compiler to save the return
381  * address register on the stack.
382  */
383 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
384 
385 #ifdef CONFIG_CPU_HAS_PREFETCH
386 
387 #define ARCH_HAS_PREFETCH
388 #define prefetch(x) __builtin_prefetch((x), 0, 1)
389 
390 #define ARCH_HAS_PREFETCHW
391 #define prefetchw(x) __builtin_prefetch((x), 1, 1)
392 
393 /*
394  * See Documentation/scheduler/sched-arch.txt; prevents deadlock on SMP
395  * systems.
396  */
397 #define __ARCH_WANT_UNLOCKED_CTXSW
398 
399 #endif
400 
401 #endif /* _ASM_PROCESSOR_H */
402