xref: /openbmc/linux/arch/arm64/include/asm/fpsimd.h (revision b40c559b)
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 #ifdef CONFIG_COMPAT
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 #endif
34 
35 struct task_struct;
36 
37 extern void fpsimd_save_state(struct user_fpsimd_state *state);
38 extern void fpsimd_load_state(struct user_fpsimd_state *state);
39 
40 extern void fpsimd_thread_switch(struct task_struct *next);
41 extern void fpsimd_flush_thread(void);
42 
43 extern void fpsimd_signal_preserve_current_state(void);
44 extern void fpsimd_preserve_current_state(void);
45 extern void fpsimd_restore_current_state(void);
46 extern void fpsimd_update_current_state(struct user_fpsimd_state const *state);
47 
48 extern void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *state,
49 				     void *sve_state, unsigned int sve_vl,
50 				     u64 *svcr);
51 
52 extern void fpsimd_flush_task_state(struct task_struct *target);
53 extern void fpsimd_save_and_flush_cpu_state(void);
54 
55 /* Maximum VL that SVE/SME VL-agnostic software can transparently support */
56 #define VL_ARCH_MAX 0x100
57 
58 /* Offset of FFR in the SVE register dump */
59 static inline size_t sve_ffr_offset(int vl)
60 {
61 	return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET;
62 }
63 
64 static inline void *sve_pffr(struct thread_struct *thread)
65 {
66 	return (char *)thread->sve_state + sve_ffr_offset(thread_get_sve_vl(thread));
67 }
68 
69 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr);
70 extern void sve_load_state(void const *state, u32 const *pfpsr,
71 			   int restore_ffr);
72 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1);
73 extern unsigned int sve_get_vl(void);
74 extern void sve_set_vq(unsigned long vq_minus_1);
75 
76 struct arm64_cpu_capabilities;
77 extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused);
78 extern void sme_kernel_enable(const struct arm64_cpu_capabilities *__unused);
79 extern void fa64_kernel_enable(const struct arm64_cpu_capabilities *__unused);
80 
81 extern u64 read_zcr_features(void);
82 extern u64 read_smcr_features(void);
83 
84 /*
85  * Helpers to translate bit indices in sve_vq_map to VQ values (and
86  * vice versa).  This allows find_next_bit() to be used to find the
87  * _maximum_ VQ not exceeding a certain value.
88  */
89 static inline unsigned int __vq_to_bit(unsigned int vq)
90 {
91 	return SVE_VQ_MAX - vq;
92 }
93 
94 static inline unsigned int __bit_to_vq(unsigned int bit)
95 {
96 	return SVE_VQ_MAX - bit;
97 }
98 
99 
100 struct vl_info {
101 	enum vec_type type;
102 	const char *name;		/* For display purposes */
103 
104 	/* Minimum supported vector length across all CPUs */
105 	int min_vl;
106 
107 	/* Maximum supported vector length across all CPUs */
108 	int max_vl;
109 	int max_virtualisable_vl;
110 
111 	/*
112 	 * Set of available vector lengths,
113 	 * where length vq encoded as bit __vq_to_bit(vq):
114 	 */
115 	DECLARE_BITMAP(vq_map, SVE_VQ_MAX);
116 
117 	/* Set of vector lengths present on at least one cpu: */
118 	DECLARE_BITMAP(vq_partial_map, SVE_VQ_MAX);
119 };
120 
121 #ifdef CONFIG_ARM64_SVE
122 
123 extern void sve_alloc(struct task_struct *task);
124 extern void fpsimd_release_task(struct task_struct *task);
125 extern void fpsimd_sync_to_sve(struct task_struct *task);
126 extern void sve_sync_to_fpsimd(struct task_struct *task);
127 extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task);
128 
129 extern int vec_set_vector_length(struct task_struct *task, enum vec_type type,
130 				 unsigned long vl, unsigned long flags);
131 
132 extern int sve_set_current_vl(unsigned long arg);
133 extern int sve_get_current_vl(void);
134 
135 static inline void sve_user_disable(void)
136 {
137 	sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
138 }
139 
140 static inline void sve_user_enable(void)
141 {
142 	sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
143 }
144 
145 #define sve_cond_update_zcr_vq(val, reg)		\
146 	do {						\
147 		u64 __zcr = read_sysreg_s((reg));	\
148 		u64 __new = __zcr & ~ZCR_ELx_LEN_MASK;	\
149 		__new |= (val) & ZCR_ELx_LEN_MASK;	\
150 		if (__zcr != __new)			\
151 			write_sysreg_s(__new, (reg));	\
152 	} while (0)
153 
154 /*
155  * Probing and setup functions.
156  * Calls to these functions must be serialised with one another.
157  */
158 enum vec_type;
159 
160 extern void __init vec_init_vq_map(enum vec_type type);
161 extern void vec_update_vq_map(enum vec_type type);
162 extern int vec_verify_vq_map(enum vec_type type);
163 extern void __init sve_setup(void);
164 
165 extern __ro_after_init struct vl_info vl_info[ARM64_VEC_MAX];
166 
167 static inline void write_vl(enum vec_type type, u64 val)
168 {
169 	u64 tmp;
170 
171 	switch (type) {
172 #ifdef CONFIG_ARM64_SVE
173 	case ARM64_VEC_SVE:
174 		tmp = read_sysreg_s(SYS_ZCR_EL1) & ~ZCR_ELx_LEN_MASK;
175 		write_sysreg_s(tmp | val, SYS_ZCR_EL1);
176 		break;
177 #endif
178 #ifdef CONFIG_ARM64_SME
179 	case ARM64_VEC_SME:
180 		tmp = read_sysreg_s(SYS_SMCR_EL1) & ~SMCR_ELx_LEN_MASK;
181 		write_sysreg_s(tmp | val, SYS_SMCR_EL1);
182 		break;
183 #endif
184 	default:
185 		WARN_ON_ONCE(1);
186 		break;
187 	}
188 }
189 
190 static inline int vec_max_vl(enum vec_type type)
191 {
192 	return vl_info[type].max_vl;
193 }
194 
195 static inline int vec_max_virtualisable_vl(enum vec_type type)
196 {
197 	return vl_info[type].max_virtualisable_vl;
198 }
199 
200 static inline int sve_max_vl(void)
201 {
202 	return vec_max_vl(ARM64_VEC_SVE);
203 }
204 
205 static inline int sve_max_virtualisable_vl(void)
206 {
207 	return vec_max_virtualisable_vl(ARM64_VEC_SVE);
208 }
209 
210 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
211 static inline bool vq_available(enum vec_type type, unsigned int vq)
212 {
213 	return test_bit(__vq_to_bit(vq), vl_info[type].vq_map);
214 }
215 
216 static inline bool sve_vq_available(unsigned int vq)
217 {
218 	return vq_available(ARM64_VEC_SVE, vq);
219 }
220 
221 #else /* ! CONFIG_ARM64_SVE */
222 
223 static inline void sve_alloc(struct task_struct *task) { }
224 static inline void fpsimd_release_task(struct task_struct *task) { }
225 static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
226 static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
227 
228 static inline int sve_max_virtualisable_vl(void)
229 {
230 	return 0;
231 }
232 
233 static inline int sve_set_current_vl(unsigned long arg)
234 {
235 	return -EINVAL;
236 }
237 
238 static inline int sve_get_current_vl(void)
239 {
240 	return -EINVAL;
241 }
242 
243 static inline int sve_max_vl(void)
244 {
245 	return -EINVAL;
246 }
247 
248 static inline bool sve_vq_available(unsigned int vq) { return false; }
249 
250 static inline void sve_user_disable(void) { BUILD_BUG(); }
251 static inline void sve_user_enable(void) { BUILD_BUG(); }
252 
253 #define sve_cond_update_zcr_vq(val, reg) do { } while (0)
254 
255 static inline void vec_init_vq_map(enum vec_type t) { }
256 static inline void vec_update_vq_map(enum vec_type t) { }
257 static inline int vec_verify_vq_map(enum vec_type t) { return 0; }
258 static inline void sve_setup(void) { }
259 
260 #endif /* ! CONFIG_ARM64_SVE */
261 
262 #ifdef CONFIG_ARM64_SME
263 
264 static inline void sme_smstart_sm(void)
265 {
266 	asm volatile(__msr_s(SYS_SVCR_SMSTART_SM_EL0, "xzr"));
267 }
268 
269 static inline void sme_smstop_sm(void)
270 {
271 	asm volatile(__msr_s(SYS_SVCR_SMSTOP_SM_EL0, "xzr"));
272 }
273 
274 static inline void sme_smstop(void)
275 {
276 	asm volatile(__msr_s(SYS_SVCR_SMSTOP_SMZA_EL0, "xzr"));
277 }
278 
279 extern void __init sme_setup(void);
280 
281 static inline int sme_max_vl(void)
282 {
283 	return vec_max_vl(ARM64_VEC_SME);
284 }
285 
286 static inline int sme_max_virtualisable_vl(void)
287 {
288 	return vec_max_virtualisable_vl(ARM64_VEC_SME);
289 }
290 
291 extern unsigned int sme_get_vl(void);
292 extern int sme_set_current_vl(unsigned long arg);
293 extern int sme_get_current_vl(void);
294 
295 #else
296 
297 static inline void sme_smstart_sm(void) { }
298 static inline void sme_smstop_sm(void) { }
299 static inline void sme_smstop(void) { }
300 
301 static inline void sme_setup(void) { }
302 static inline unsigned int sme_get_vl(void) { return 0; }
303 static inline int sme_max_vl(void) { return 0; }
304 static inline int sme_max_virtualisable_vl(void) { return 0; }
305 static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; }
306 static inline int sme_get_current_vl(void) { return -EINVAL; }
307 
308 #endif /* ! CONFIG_ARM64_SME */
309 
310 /* For use by EFI runtime services calls only */
311 extern void __efi_fpsimd_begin(void);
312 extern void __efi_fpsimd_end(void);
313 
314 #endif
315 
316 #endif
317