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