1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5 #ifndef __ASM_FP_H
6 #define __ASM_FP_H
7
8 #include <asm/errno.h>
9 #include <asm/percpu.h>
10 #include <asm/ptrace.h>
11 #include <asm/processor.h>
12 #include <asm/sigcontext.h>
13 #include <asm/sysreg.h>
14
15 #ifndef __ASSEMBLY__
16
17 #include <linux/bitmap.h>
18 #include <linux/build_bug.h>
19 #include <linux/bug.h>
20 #include <linux/cache.h>
21 #include <linux/init.h>
22 #include <linux/stddef.h>
23 #include <linux/types.h>
24
25 /* Masks for extracting the FPSR and FPCR from the FPSCR */
26 #define VFP_FPSCR_STAT_MASK 0xf800009f
27 #define VFP_FPSCR_CTRL_MASK 0x07f79f00
28 /*
29 * The VFP state has 32x64-bit registers and a single 32-bit
30 * control/status register.
31 */
32 #define VFP_STATE_SIZE ((32 * 8) + 4)
33
cpacr_save_enable_kernel_sve(void)34 static inline unsigned long cpacr_save_enable_kernel_sve(void)
35 {
36 unsigned long old = read_sysreg(cpacr_el1);
37 unsigned long set = CPACR_EL1_FPEN_EL1EN | CPACR_EL1_ZEN_EL1EN;
38
39 write_sysreg(old | set, cpacr_el1);
40 isb();
41 return old;
42 }
43
cpacr_save_enable_kernel_sme(void)44 static inline unsigned long cpacr_save_enable_kernel_sme(void)
45 {
46 unsigned long old = read_sysreg(cpacr_el1);
47 unsigned long set = CPACR_EL1_FPEN_EL1EN | CPACR_EL1_SMEN_EL1EN;
48
49 write_sysreg(old | set, cpacr_el1);
50 isb();
51 return old;
52 }
53
cpacr_restore(unsigned long cpacr)54 static inline void cpacr_restore(unsigned long cpacr)
55 {
56 write_sysreg(cpacr, cpacr_el1);
57 isb();
58 }
59
60 /*
61 * When we defined the maximum SVE vector length we defined the ABI so
62 * that the maximum vector length included all the reserved for future
63 * expansion bits in ZCR rather than those just currently defined by
64 * the architecture. Using this length to allocate worst size buffers
65 * results in excessively large allocations, and this effect is even
66 * more pronounced for SME due to ZA. Define more suitable VLs for
67 * these situations.
68 */
69 #define ARCH_SVE_VQ_MAX ((ZCR_ELx_LEN_MASK >> ZCR_ELx_LEN_SHIFT) + 1)
70 #define SME_VQ_MAX ((SMCR_ELx_LEN_MASK >> SMCR_ELx_LEN_SHIFT) + 1)
71
72 struct task_struct;
73
74 extern void fpsimd_save_state(struct user_fpsimd_state *state);
75 extern void fpsimd_load_state(struct user_fpsimd_state *state);
76
77 extern void fpsimd_thread_switch(struct task_struct *next);
78 extern void fpsimd_flush_thread(void);
79
80 extern void fpsimd_preserve_current_state(void);
81 extern void fpsimd_restore_current_state(void);
82 extern void fpsimd_update_current_state(struct user_fpsimd_state const *state);
83
84 struct cpu_fp_state {
85 struct user_fpsimd_state *st;
86 void *sve_state;
87 void *sme_state;
88 u64 *svcr;
89 u64 *fpmr;
90 unsigned int sve_vl;
91 unsigned int sme_vl;
92 enum fp_type *fp_type;
93 enum fp_type to_save;
94 };
95
96 DECLARE_PER_CPU(struct cpu_fp_state, fpsimd_last_state);
97
98 extern void fpsimd_bind_state_to_cpu(struct cpu_fp_state *fp_state);
99
100 extern void fpsimd_flush_task_state(struct task_struct *target);
101 extern void fpsimd_save_and_flush_current_state(void);
102 extern void fpsimd_save_and_flush_cpu_state(void);
103
thread_sm_enabled(struct thread_struct * thread)104 static inline bool thread_sm_enabled(struct thread_struct *thread)
105 {
106 return system_supports_sme() && (thread->svcr & SVCR_SM_MASK);
107 }
108
thread_za_enabled(struct thread_struct * thread)109 static inline bool thread_za_enabled(struct thread_struct *thread)
110 {
111 return system_supports_sme() && (thread->svcr & SVCR_ZA_MASK);
112 }
113
114 extern void task_smstop_sm(struct task_struct *task);
115
116 /* Maximum VL that SVE/SME VL-agnostic software can transparently support */
117 #define VL_ARCH_MAX 0x100
118
119 /* Offset of FFR in the SVE register dump */
sve_ffr_offset(int vl)120 static inline size_t sve_ffr_offset(int vl)
121 {
122 return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET;
123 }
124
sve_pffr(struct thread_struct * thread)125 static inline void *sve_pffr(struct thread_struct *thread)
126 {
127 unsigned int vl;
128
129 if (system_supports_sme() && thread_sm_enabled(thread))
130 vl = thread_get_sme_vl(thread);
131 else
132 vl = thread_get_sve_vl(thread);
133
134 return (char *)thread->sve_state + sve_ffr_offset(vl);
135 }
136
thread_zt_state(struct thread_struct * thread)137 static inline void *thread_zt_state(struct thread_struct *thread)
138 {
139 /* The ZT register state is stored immediately after the ZA state */
140 unsigned int sme_vq = sve_vq_from_vl(thread_get_sme_vl(thread));
141 return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq);
142 }
143
144 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr);
145 extern void sve_load_state(void const *state, u32 const *pfpsr,
146 int restore_ffr);
147 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1);
148 extern unsigned int sve_get_vl(void);
149 extern void sve_set_vq(unsigned long vq_minus_1);
150 extern void sme_set_vq(unsigned long vq_minus_1);
151 extern void sme_save_state(void *state, int zt);
152 extern void sme_load_state(void const *state, int zt);
153
154 struct arm64_cpu_capabilities;
155 extern void cpu_enable_fpsimd(const struct arm64_cpu_capabilities *__unused);
156 extern void cpu_enable_sve(const struct arm64_cpu_capabilities *__unused);
157 extern void cpu_enable_sme(const struct arm64_cpu_capabilities *__unused);
158 extern void cpu_enable_sme2(const struct arm64_cpu_capabilities *__unused);
159 extern void cpu_enable_fa64(const struct arm64_cpu_capabilities *__unused);
160 extern void cpu_enable_fpmr(const struct arm64_cpu_capabilities *__unused);
161
162 /*
163 * Helpers to translate bit indices in sve_vq_map to VQ values (and
164 * vice versa). This allows find_next_bit() to be used to find the
165 * _maximum_ VQ not exceeding a certain value.
166 */
__vq_to_bit(unsigned int vq)167 static inline unsigned int __vq_to_bit(unsigned int vq)
168 {
169 return SVE_VQ_MAX - vq;
170 }
171
__bit_to_vq(unsigned int bit)172 static inline unsigned int __bit_to_vq(unsigned int bit)
173 {
174 return SVE_VQ_MAX - bit;
175 }
176
177
178 struct vl_info {
179 enum vec_type type;
180 const char *name; /* For display purposes */
181
182 /* Minimum supported vector length across all CPUs */
183 int min_vl;
184
185 /* Maximum supported vector length across all CPUs */
186 int max_vl;
187 int max_virtualisable_vl;
188
189 /*
190 * Set of available vector lengths,
191 * where length vq encoded as bit __vq_to_bit(vq):
192 */
193 DECLARE_BITMAP(vq_map, SVE_VQ_MAX);
194
195 /* Set of vector lengths present on at least one cpu: */
196 DECLARE_BITMAP(vq_partial_map, SVE_VQ_MAX);
197 };
198
199 #ifdef CONFIG_ARM64_SVE
200
201 extern void sve_alloc(struct task_struct *task, bool flush);
202 extern void fpsimd_release_task(struct task_struct *task);
203 extern void fpsimd_sync_from_effective_state(struct task_struct *task);
204 extern void fpsimd_sync_to_effective_state_zeropad(struct task_struct *task);
205
206 extern int vec_set_vector_length(struct task_struct *task, enum vec_type type,
207 unsigned long vl, unsigned long flags);
208
209 extern int sve_set_current_vl(unsigned long arg);
210 extern int sve_get_current_vl(void);
211
sve_user_disable(void)212 static inline void sve_user_disable(void)
213 {
214 sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
215 }
216
sve_user_enable(void)217 static inline void sve_user_enable(void)
218 {
219 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
220 }
221
222 #define sve_cond_update_zcr_vq(val, reg) \
223 do { \
224 u64 __zcr = read_sysreg_s((reg)); \
225 u64 __new = __zcr & ~ZCR_ELx_LEN_MASK; \
226 __new |= (val) & ZCR_ELx_LEN_MASK; \
227 if (__zcr != __new) \
228 write_sysreg_s(__new, (reg)); \
229 } while (0)
230
231 /*
232 * Probing and setup functions.
233 * Calls to these functions must be serialised with one another.
234 */
235 enum vec_type;
236
237 extern void __init vec_init_vq_map(enum vec_type type);
238 extern void vec_update_vq_map(enum vec_type type);
239 extern int vec_verify_vq_map(enum vec_type type);
240 extern void __init sve_setup(void);
241
242 extern __ro_after_init struct vl_info vl_info[ARM64_VEC_MAX];
243
write_vl(enum vec_type type,u64 val)244 static inline void write_vl(enum vec_type type, u64 val)
245 {
246 u64 tmp;
247
248 switch (type) {
249 #ifdef CONFIG_ARM64_SVE
250 case ARM64_VEC_SVE:
251 tmp = read_sysreg_s(SYS_ZCR_EL1) & ~ZCR_ELx_LEN_MASK;
252 write_sysreg_s(tmp | val, SYS_ZCR_EL1);
253 break;
254 #endif
255 #ifdef CONFIG_ARM64_SME
256 case ARM64_VEC_SME:
257 tmp = read_sysreg_s(SYS_SMCR_EL1) & ~SMCR_ELx_LEN_MASK;
258 write_sysreg_s(tmp | val, SYS_SMCR_EL1);
259 break;
260 #endif
261 default:
262 WARN_ON_ONCE(1);
263 break;
264 }
265 }
266
vec_max_vl(enum vec_type type)267 static inline int vec_max_vl(enum vec_type type)
268 {
269 return vl_info[type].max_vl;
270 }
271
vec_max_virtualisable_vl(enum vec_type type)272 static inline int vec_max_virtualisable_vl(enum vec_type type)
273 {
274 return vl_info[type].max_virtualisable_vl;
275 }
276
sve_max_vl(void)277 static inline int sve_max_vl(void)
278 {
279 return vec_max_vl(ARM64_VEC_SVE);
280 }
281
sve_max_virtualisable_vl(void)282 static inline int sve_max_virtualisable_vl(void)
283 {
284 return vec_max_virtualisable_vl(ARM64_VEC_SVE);
285 }
286
287 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
vq_available(enum vec_type type,unsigned int vq)288 static inline bool vq_available(enum vec_type type, unsigned int vq)
289 {
290 return test_bit(__vq_to_bit(vq), vl_info[type].vq_map);
291 }
292
sve_vq_available(unsigned int vq)293 static inline bool sve_vq_available(unsigned int vq)
294 {
295 return vq_available(ARM64_VEC_SVE, vq);
296 }
297
__sve_state_size(unsigned int sve_vl,unsigned int sme_vl)298 static inline size_t __sve_state_size(unsigned int sve_vl, unsigned int sme_vl)
299 {
300 unsigned int vl = max(sve_vl, sme_vl);
301 return SVE_SIG_REGS_SIZE(sve_vq_from_vl(vl));
302 }
303
304 /*
305 * Return how many bytes of memory are required to store the full SVE
306 * state for task, given task's currently configured vector length.
307 */
sve_state_size(struct task_struct const * task)308 static inline size_t sve_state_size(struct task_struct const *task)
309 {
310 unsigned int sve_vl = task_get_sve_vl(task);
311 unsigned int sme_vl = task_get_sme_vl(task);
312 return __sve_state_size(sve_vl, sme_vl);
313 }
314
315 #else /* ! CONFIG_ARM64_SVE */
316
sve_alloc(struct task_struct * task,bool flush)317 static inline void sve_alloc(struct task_struct *task, bool flush) { }
fpsimd_release_task(struct task_struct * task)318 static inline void fpsimd_release_task(struct task_struct *task) { }
fpsimd_sync_from_effective_state(struct task_struct * task)319 static inline void fpsimd_sync_from_effective_state(struct task_struct *task) { }
fpsimd_sync_to_effective_state_zeropad(struct task_struct * task)320 static inline void fpsimd_sync_to_effective_state_zeropad(struct task_struct *task) { }
321
sve_max_virtualisable_vl(void)322 static inline int sve_max_virtualisable_vl(void)
323 {
324 return 0;
325 }
326
sve_set_current_vl(unsigned long arg)327 static inline int sve_set_current_vl(unsigned long arg)
328 {
329 return -EINVAL;
330 }
331
sve_get_current_vl(void)332 static inline int sve_get_current_vl(void)
333 {
334 return -EINVAL;
335 }
336
sve_max_vl(void)337 static inline int sve_max_vl(void)
338 {
339 return -EINVAL;
340 }
341
sve_vq_available(unsigned int vq)342 static inline bool sve_vq_available(unsigned int vq) { return false; }
343
sve_user_disable(void)344 static inline void sve_user_disable(void) { BUILD_BUG(); }
sve_user_enable(void)345 static inline void sve_user_enable(void) { BUILD_BUG(); }
346
347 #define sve_cond_update_zcr_vq(val, reg) do { } while (0)
348
vec_init_vq_map(enum vec_type t)349 static inline void vec_init_vq_map(enum vec_type t) { }
vec_update_vq_map(enum vec_type t)350 static inline void vec_update_vq_map(enum vec_type t) { }
vec_verify_vq_map(enum vec_type t)351 static inline int vec_verify_vq_map(enum vec_type t) { return 0; }
sve_setup(void)352 static inline void sve_setup(void) { }
353
__sve_state_size(unsigned int sve_vl,unsigned int sme_vl)354 static inline size_t __sve_state_size(unsigned int sve_vl, unsigned int sme_vl)
355 {
356 return 0;
357 }
358
sve_state_size(struct task_struct const * task)359 static inline size_t sve_state_size(struct task_struct const *task)
360 {
361 return 0;
362 }
363
364 #endif /* ! CONFIG_ARM64_SVE */
365
366 #ifdef CONFIG_ARM64_SME
367
sme_user_disable(void)368 static inline void sme_user_disable(void)
369 {
370 sysreg_clear_set(cpacr_el1, CPACR_EL1_SMEN_EL0EN, 0);
371 }
372
sme_user_enable(void)373 static inline void sme_user_enable(void)
374 {
375 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_SMEN_EL0EN);
376 }
377
sme_smstart_sm(void)378 static inline void sme_smstart_sm(void)
379 {
380 asm volatile(__msr_s(SYS_SVCR_SMSTART_SM_EL0, "xzr"));
381 }
382
sme_smstop_sm(void)383 static inline void sme_smstop_sm(void)
384 {
385 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SM_EL0, "xzr"));
386 }
387
sme_smstop(void)388 static inline void sme_smstop(void)
389 {
390 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SMZA_EL0, "xzr"));
391 }
392
393 extern void __init sme_setup(void);
394
sme_max_vl(void)395 static inline int sme_max_vl(void)
396 {
397 return vec_max_vl(ARM64_VEC_SME);
398 }
399
sme_max_virtualisable_vl(void)400 static inline int sme_max_virtualisable_vl(void)
401 {
402 return vec_max_virtualisable_vl(ARM64_VEC_SME);
403 }
404
405 extern void sme_alloc(struct task_struct *task, bool flush);
406 extern unsigned int sme_get_vl(void);
407 extern int sme_set_current_vl(unsigned long arg);
408 extern int sme_get_current_vl(void);
409 extern void sme_suspend_exit(void);
410
__sme_state_size(unsigned int sme_vl)411 static inline size_t __sme_state_size(unsigned int sme_vl)
412 {
413 size_t size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(sme_vl));
414
415 if (system_supports_sme2())
416 size += ZT_SIG_REG_SIZE;
417
418 return size;
419 }
420
421 /*
422 * Return how many bytes of memory are required to store the full SME
423 * specific state for task, given task's currently configured vector
424 * length.
425 */
sme_state_size(struct task_struct const * task)426 static inline size_t sme_state_size(struct task_struct const *task)
427 {
428 return __sme_state_size(task_get_sme_vl(task));
429 }
430
431 #else
432
sme_user_disable(void)433 static inline void sme_user_disable(void) { BUILD_BUG(); }
sme_user_enable(void)434 static inline void sme_user_enable(void) { BUILD_BUG(); }
435
sme_smstart_sm(void)436 static inline void sme_smstart_sm(void) { }
sme_smstop_sm(void)437 static inline void sme_smstop_sm(void) { }
sme_smstop(void)438 static inline void sme_smstop(void) { }
439
sme_alloc(struct task_struct * task,bool flush)440 static inline void sme_alloc(struct task_struct *task, bool flush) { }
sme_setup(void)441 static inline void sme_setup(void) { }
sme_get_vl(void)442 static inline unsigned int sme_get_vl(void) { return 0; }
sme_max_vl(void)443 static inline int sme_max_vl(void) { return 0; }
sme_max_virtualisable_vl(void)444 static inline int sme_max_virtualisable_vl(void) { return 0; }
sme_set_current_vl(unsigned long arg)445 static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; }
sme_get_current_vl(void)446 static inline int sme_get_current_vl(void) { return -EINVAL; }
sme_suspend_exit(void)447 static inline void sme_suspend_exit(void) { }
448
__sme_state_size(unsigned int sme_vl)449 static inline size_t __sme_state_size(unsigned int sme_vl)
450 {
451 return 0;
452 }
453
sme_state_size(struct task_struct const * task)454 static inline size_t sme_state_size(struct task_struct const *task)
455 {
456 return 0;
457 }
458
459 #endif /* ! CONFIG_ARM64_SME */
460
461 /* For use by EFI runtime services calls only */
462 extern void __efi_fpsimd_begin(void);
463 extern void __efi_fpsimd_end(void);
464
465 #endif
466
467 #endif
468