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 extern void fpsimd_kvm_prepare(void);
84
85 struct cpu_fp_state {
86 struct user_fpsimd_state *st;
87 void *sve_state;
88 void *sme_state;
89 u64 *svcr;
90 u64 *fpmr;
91 unsigned int sve_vl;
92 unsigned int sme_vl;
93 enum fp_type *fp_type;
94 enum fp_type to_save;
95 };
96
97 DECLARE_PER_CPU(struct cpu_fp_state, fpsimd_last_state);
98
99 extern void fpsimd_bind_state_to_cpu(struct cpu_fp_state *fp_state);
100
101 extern void fpsimd_flush_task_state(struct task_struct *target);
102 extern void fpsimd_save_and_flush_current_state(void);
103 extern void fpsimd_save_and_flush_cpu_state(void);
104
thread_sm_enabled(struct thread_struct * thread)105 static inline bool thread_sm_enabled(struct thread_struct *thread)
106 {
107 return system_supports_sme() && (thread->svcr & SVCR_SM_MASK);
108 }
109
thread_za_enabled(struct thread_struct * thread)110 static inline bool thread_za_enabled(struct thread_struct *thread)
111 {
112 return system_supports_sme() && (thread->svcr & SVCR_ZA_MASK);
113 }
114
115 extern void task_smstop_sm(struct task_struct *task);
116
117 /* Maximum VL that SVE/SME VL-agnostic software can transparently support */
118 #define VL_ARCH_MAX 0x100
119
120 /* Offset of FFR in the SVE register dump */
sve_ffr_offset(int vl)121 static inline size_t sve_ffr_offset(int vl)
122 {
123 return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET;
124 }
125
sve_pffr(struct thread_struct * thread)126 static inline void *sve_pffr(struct thread_struct *thread)
127 {
128 unsigned int vl;
129
130 if (system_supports_sme() && thread_sm_enabled(thread))
131 vl = thread_get_sme_vl(thread);
132 else
133 vl = thread_get_sve_vl(thread);
134
135 return (char *)thread->sve_state + sve_ffr_offset(vl);
136 }
137
thread_zt_state(struct thread_struct * thread)138 static inline void *thread_zt_state(struct thread_struct *thread)
139 {
140 /* The ZT register state is stored immediately after the ZA state */
141 unsigned int sme_vq = sve_vq_from_vl(thread_get_sme_vl(thread));
142 return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq);
143 }
144
145 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr);
146 extern void sve_load_state(void const *state, u32 const *pfpsr,
147 int restore_ffr);
148 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1);
149 extern unsigned int sve_get_vl(void);
150 extern void sve_set_vq(unsigned long vq_minus_1);
151 extern void sme_set_vq(unsigned long vq_minus_1);
152 extern void sme_save_state(void *state, int zt);
153 extern void sme_load_state(void const *state, int zt);
154
155 struct arm64_cpu_capabilities;
156 extern void cpu_enable_fpsimd(const struct arm64_cpu_capabilities *__unused);
157 extern void cpu_enable_sve(const struct arm64_cpu_capabilities *__unused);
158 extern void cpu_enable_sme(const struct arm64_cpu_capabilities *__unused);
159 extern void cpu_enable_sme2(const struct arm64_cpu_capabilities *__unused);
160 extern void cpu_enable_fa64(const struct arm64_cpu_capabilities *__unused);
161 extern void cpu_enable_fpmr(const struct arm64_cpu_capabilities *__unused);
162
163 /*
164 * Helpers to translate bit indices in sve_vq_map to VQ values (and
165 * vice versa). This allows find_next_bit() to be used to find the
166 * _maximum_ VQ not exceeding a certain value.
167 */
__vq_to_bit(unsigned int vq)168 static inline unsigned int __vq_to_bit(unsigned int vq)
169 {
170 return SVE_VQ_MAX - vq;
171 }
172
__bit_to_vq(unsigned int bit)173 static inline unsigned int __bit_to_vq(unsigned int bit)
174 {
175 return SVE_VQ_MAX - bit;
176 }
177
178
179 struct vl_info {
180 enum vec_type type;
181 const char *name; /* For display purposes */
182
183 /* Minimum supported vector length across all CPUs */
184 int min_vl;
185
186 /* Maximum supported vector length across all CPUs */
187 int max_vl;
188 int max_virtualisable_vl;
189
190 /*
191 * Set of available vector lengths,
192 * where length vq encoded as bit __vq_to_bit(vq):
193 */
194 DECLARE_BITMAP(vq_map, SVE_VQ_MAX);
195
196 /* Set of vector lengths present on at least one cpu: */
197 DECLARE_BITMAP(vq_partial_map, SVE_VQ_MAX);
198 };
199
200 #ifdef CONFIG_ARM64_SVE
201
202 extern void sve_alloc(struct task_struct *task, bool flush);
203 extern void fpsimd_release_task(struct task_struct *task);
204 extern void fpsimd_sync_from_effective_state(struct task_struct *task);
205 extern void fpsimd_sync_to_effective_state_zeropad(struct task_struct *task);
206
207 extern int vec_set_vector_length(struct task_struct *task, enum vec_type type,
208 unsigned long vl, unsigned long flags);
209
210 extern int sve_set_current_vl(unsigned long arg);
211 extern int sve_get_current_vl(void);
212
sve_user_disable(void)213 static inline void sve_user_disable(void)
214 {
215 sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
216 }
217
sve_user_enable(void)218 static inline void sve_user_enable(void)
219 {
220 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
221 }
222
223 #define sve_cond_update_zcr_vq(val, reg) \
224 do { \
225 u64 __zcr = read_sysreg_s((reg)); \
226 u64 __new = __zcr & ~ZCR_ELx_LEN_MASK; \
227 __new |= (val) & ZCR_ELx_LEN_MASK; \
228 if (__zcr != __new) \
229 write_sysreg_s(__new, (reg)); \
230 } while (0)
231
232 /*
233 * Probing and setup functions.
234 * Calls to these functions must be serialised with one another.
235 */
236 enum vec_type;
237
238 extern void __init vec_init_vq_map(enum vec_type type);
239 extern void vec_update_vq_map(enum vec_type type);
240 extern int vec_verify_vq_map(enum vec_type type);
241 extern void __init sve_setup(void);
242
243 extern __ro_after_init struct vl_info vl_info[ARM64_VEC_MAX];
244
write_vl(enum vec_type type,u64 val)245 static inline void write_vl(enum vec_type type, u64 val)
246 {
247 u64 tmp;
248
249 switch (type) {
250 #ifdef CONFIG_ARM64_SVE
251 case ARM64_VEC_SVE:
252 tmp = read_sysreg_s(SYS_ZCR_EL1) & ~ZCR_ELx_LEN_MASK;
253 write_sysreg_s(tmp | val, SYS_ZCR_EL1);
254 break;
255 #endif
256 #ifdef CONFIG_ARM64_SME
257 case ARM64_VEC_SME:
258 tmp = read_sysreg_s(SYS_SMCR_EL1) & ~SMCR_ELx_LEN_MASK;
259 write_sysreg_s(tmp | val, SYS_SMCR_EL1);
260 break;
261 #endif
262 default:
263 WARN_ON_ONCE(1);
264 break;
265 }
266 }
267
vec_max_vl(enum vec_type type)268 static inline int vec_max_vl(enum vec_type type)
269 {
270 return vl_info[type].max_vl;
271 }
272
vec_max_virtualisable_vl(enum vec_type type)273 static inline int vec_max_virtualisable_vl(enum vec_type type)
274 {
275 return vl_info[type].max_virtualisable_vl;
276 }
277
sve_max_vl(void)278 static inline int sve_max_vl(void)
279 {
280 return vec_max_vl(ARM64_VEC_SVE);
281 }
282
sve_max_virtualisable_vl(void)283 static inline int sve_max_virtualisable_vl(void)
284 {
285 return vec_max_virtualisable_vl(ARM64_VEC_SVE);
286 }
287
288 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
vq_available(enum vec_type type,unsigned int vq)289 static inline bool vq_available(enum vec_type type, unsigned int vq)
290 {
291 return test_bit(__vq_to_bit(vq), vl_info[type].vq_map);
292 }
293
sve_vq_available(unsigned int vq)294 static inline bool sve_vq_available(unsigned int vq)
295 {
296 return vq_available(ARM64_VEC_SVE, vq);
297 }
298
__sve_state_size(unsigned int sve_vl,unsigned int sme_vl)299 static inline size_t __sve_state_size(unsigned int sve_vl, unsigned int sme_vl)
300 {
301 unsigned int vl = max(sve_vl, sme_vl);
302 return SVE_SIG_REGS_SIZE(sve_vq_from_vl(vl));
303 }
304
305 /*
306 * Return how many bytes of memory are required to store the full SVE
307 * state for task, given task's currently configured vector length.
308 */
sve_state_size(struct task_struct const * task)309 static inline size_t sve_state_size(struct task_struct const *task)
310 {
311 unsigned int sve_vl = task_get_sve_vl(task);
312 unsigned int sme_vl = task_get_sme_vl(task);
313 return __sve_state_size(sve_vl, sme_vl);
314 }
315
316 #else /* ! CONFIG_ARM64_SVE */
317
sve_alloc(struct task_struct * task,bool flush)318 static inline void sve_alloc(struct task_struct *task, bool flush) { }
fpsimd_release_task(struct task_struct * task)319 static inline void fpsimd_release_task(struct task_struct *task) { }
fpsimd_sync_from_effective_state(struct task_struct * task)320 static inline void fpsimd_sync_from_effective_state(struct task_struct *task) { }
fpsimd_sync_to_effective_state_zeropad(struct task_struct * task)321 static inline void fpsimd_sync_to_effective_state_zeropad(struct task_struct *task) { }
322
sve_max_virtualisable_vl(void)323 static inline int sve_max_virtualisable_vl(void)
324 {
325 return 0;
326 }
327
sve_set_current_vl(unsigned long arg)328 static inline int sve_set_current_vl(unsigned long arg)
329 {
330 return -EINVAL;
331 }
332
sve_get_current_vl(void)333 static inline int sve_get_current_vl(void)
334 {
335 return -EINVAL;
336 }
337
sve_max_vl(void)338 static inline int sve_max_vl(void)
339 {
340 return -EINVAL;
341 }
342
sve_vq_available(unsigned int vq)343 static inline bool sve_vq_available(unsigned int vq) { return false; }
344
sve_user_disable(void)345 static inline void sve_user_disable(void) { BUILD_BUG(); }
sve_user_enable(void)346 static inline void sve_user_enable(void) { BUILD_BUG(); }
347
348 #define sve_cond_update_zcr_vq(val, reg) do { } while (0)
349
vec_init_vq_map(enum vec_type t)350 static inline void vec_init_vq_map(enum vec_type t) { }
vec_update_vq_map(enum vec_type t)351 static inline void vec_update_vq_map(enum vec_type t) { }
vec_verify_vq_map(enum vec_type t)352 static inline int vec_verify_vq_map(enum vec_type t) { return 0; }
sve_setup(void)353 static inline void sve_setup(void) { }
354
__sve_state_size(unsigned int sve_vl,unsigned int sme_vl)355 static inline size_t __sve_state_size(unsigned int sve_vl, unsigned int sme_vl)
356 {
357 return 0;
358 }
359
sve_state_size(struct task_struct const * task)360 static inline size_t sve_state_size(struct task_struct const *task)
361 {
362 return 0;
363 }
364
365 #endif /* ! CONFIG_ARM64_SVE */
366
367 #ifdef CONFIG_ARM64_SME
368
sme_user_disable(void)369 static inline void sme_user_disable(void)
370 {
371 sysreg_clear_set(cpacr_el1, CPACR_EL1_SMEN_EL0EN, 0);
372 }
373
sme_user_enable(void)374 static inline void sme_user_enable(void)
375 {
376 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_SMEN_EL0EN);
377 }
378
sme_smstart_sm(void)379 static inline void sme_smstart_sm(void)
380 {
381 asm volatile(__msr_s(SYS_SVCR_SMSTART_SM_EL0, "xzr"));
382 }
383
sme_smstop_sm(void)384 static inline void sme_smstop_sm(void)
385 {
386 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SM_EL0, "xzr"));
387 }
388
sme_smstop(void)389 static inline void sme_smstop(void)
390 {
391 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SMZA_EL0, "xzr"));
392 }
393
394 extern void __init sme_setup(void);
395
sme_max_vl(void)396 static inline int sme_max_vl(void)
397 {
398 return vec_max_vl(ARM64_VEC_SME);
399 }
400
sme_max_virtualisable_vl(void)401 static inline int sme_max_virtualisable_vl(void)
402 {
403 return vec_max_virtualisable_vl(ARM64_VEC_SME);
404 }
405
406 extern void sme_alloc(struct task_struct *task, bool flush);
407 extern unsigned int sme_get_vl(void);
408 extern int sme_set_current_vl(unsigned long arg);
409 extern int sme_get_current_vl(void);
410 extern void sme_suspend_exit(void);
411
__sme_state_size(unsigned int sme_vl)412 static inline size_t __sme_state_size(unsigned int sme_vl)
413 {
414 size_t size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(sme_vl));
415
416 if (system_supports_sme2())
417 size += ZT_SIG_REG_SIZE;
418
419 return size;
420 }
421
422 /*
423 * Return how many bytes of memory are required to store the full SME
424 * specific state for task, given task's currently configured vector
425 * length.
426 */
sme_state_size(struct task_struct const * task)427 static inline size_t sme_state_size(struct task_struct const *task)
428 {
429 return __sme_state_size(task_get_sme_vl(task));
430 }
431
432 #else
433
sme_user_disable(void)434 static inline void sme_user_disable(void) { BUILD_BUG(); }
sme_user_enable(void)435 static inline void sme_user_enable(void) { BUILD_BUG(); }
436
sme_smstart_sm(void)437 static inline void sme_smstart_sm(void) { }
sme_smstop_sm(void)438 static inline void sme_smstop_sm(void) { }
sme_smstop(void)439 static inline void sme_smstop(void) { }
440
sme_alloc(struct task_struct * task,bool flush)441 static inline void sme_alloc(struct task_struct *task, bool flush) { }
sme_setup(void)442 static inline void sme_setup(void) { }
sme_get_vl(void)443 static inline unsigned int sme_get_vl(void) { return 0; }
sme_max_vl(void)444 static inline int sme_max_vl(void) { return 0; }
sme_max_virtualisable_vl(void)445 static inline int sme_max_virtualisable_vl(void) { return 0; }
sme_set_current_vl(unsigned long arg)446 static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; }
sme_get_current_vl(void)447 static inline int sme_get_current_vl(void) { return -EINVAL; }
sme_suspend_exit(void)448 static inline void sme_suspend_exit(void) { }
449
__sme_state_size(unsigned int sme_vl)450 static inline size_t __sme_state_size(unsigned int sme_vl)
451 {
452 return 0;
453 }
454
sme_state_size(struct task_struct const * task)455 static inline size_t sme_state_size(struct task_struct const *task)
456 {
457 return 0;
458 }
459
460 #endif /* ! CONFIG_ARM64_SME */
461
462 /* For use by EFI runtime services calls only */
463 extern void __efi_fpsimd_begin(void);
464 extern void __efi_fpsimd_end(void);
465
466 #endif
467
468 #endif
469