Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/vfp/vfpmodule.c |
| 3 | * |
| 4 | * Copyright (C) 2004 ARM Limited. |
| 5 | * Written by Deep Blue Solutions Limited. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/types.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/signal.h> |
| 15 | #include <linux/sched.h> |
| 16 | #include <linux/init.h> |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 17 | |
| 18 | #include <asm/thread_notify.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <asm/vfp.h> |
| 20 | |
| 21 | #include "vfpinstr.h" |
| 22 | #include "vfp.h" |
| 23 | |
| 24 | /* |
| 25 | * Our undef handlers (in entry.S) |
| 26 | */ |
| 27 | void vfp_testing_entry(void); |
| 28 | void vfp_support_entry(void); |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 29 | void vfp_null_entry(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 31 | void (*vfp_vector)(void) = vfp_null_entry; |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 32 | union vfp_state *last_VFP_context[NR_CPUS]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | |
| 34 | /* |
| 35 | * Dual-use variable. |
| 36 | * Used in startup: set to non-zero if VFP checks fail |
| 37 | * After startup, holds VFP architecture |
| 38 | */ |
| 39 | unsigned int VFP_arch; |
| 40 | |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 41 | static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | { |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 43 | struct thread_info *thread = v; |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 44 | union vfp_state *vfp; |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 45 | __u32 cpu = thread->cpu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 47 | if (likely(cmd == THREAD_NOTIFY_SWITCH)) { |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 48 | u32 fpexc = fmrx(FPEXC); |
| 49 | |
| 50 | #ifdef CONFIG_SMP |
| 51 | /* |
| 52 | * On SMP, if VFP is enabled, save the old state in |
| 53 | * case the thread migrates to a different CPU. The |
| 54 | * restoring is done lazily. |
| 55 | */ |
Russell King | 228adef | 2007-07-18 09:37:10 +0100 | [diff] [blame] | 56 | if ((fpexc & FPEXC_EN) && last_VFP_context[cpu]) { |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 57 | vfp_save_state(last_VFP_context[cpu], fpexc); |
| 58 | last_VFP_context[cpu]->hard.cpu = cpu; |
| 59 | } |
| 60 | /* |
| 61 | * Thread migration, just force the reloading of the |
| 62 | * state on the new CPU in case the VFP registers |
| 63 | * contain stale data. |
| 64 | */ |
| 65 | if (thread->vfpstate.hard.cpu != cpu) |
| 66 | last_VFP_context[cpu] = NULL; |
| 67 | #endif |
| 68 | |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 69 | /* |
| 70 | * Always disable VFP so we can lazily save/restore the |
| 71 | * old state. |
| 72 | */ |
Russell King | 228adef | 2007-07-18 09:37:10 +0100 | [diff] [blame] | 73 | fmxr(FPEXC, fpexc & ~FPEXC_EN); |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 74 | return NOTIFY_DONE; |
| 75 | } |
| 76 | |
| 77 | vfp = &thread->vfpstate; |
| 78 | if (cmd == THREAD_NOTIFY_FLUSH) { |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 79 | /* |
| 80 | * Per-thread VFP initialisation. |
| 81 | */ |
| 82 | memset(vfp, 0, sizeof(union vfp_state)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | |
Russell King | 228adef | 2007-07-18 09:37:10 +0100 | [diff] [blame] | 84 | vfp->hard.fpexc = FPEXC_EN; |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 85 | vfp->hard.fpscr = FPSCR_ROUND_NEAREST; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 87 | /* |
| 88 | * Disable VFP to ensure we initialise it first. |
| 89 | */ |
Russell King | 228adef | 2007-07-18 09:37:10 +0100 | [diff] [blame] | 90 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 91 | } |
| 92 | |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 93 | /* flush and release case: Per-thread VFP cleanup. */ |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 94 | if (last_VFP_context[cpu] == vfp) |
| 95 | last_VFP_context[cpu] = NULL; |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 96 | |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 97 | return NOTIFY_DONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | } |
| 99 | |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 100 | static struct notifier_block vfp_notifier_block = { |
| 101 | .notifier_call = vfp_notifier, |
| 102 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | |
| 104 | /* |
| 105 | * Raise a SIGFPE for the current process. |
| 106 | * sicode describes the signal being raised. |
| 107 | */ |
| 108 | void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs) |
| 109 | { |
| 110 | siginfo_t info; |
| 111 | |
| 112 | memset(&info, 0, sizeof(info)); |
| 113 | |
| 114 | info.si_signo = SIGFPE; |
| 115 | info.si_code = sicode; |
Al Viro | 35d59fc | 2006-10-11 17:22:44 +0100 | [diff] [blame] | 116 | info.si_addr = (void __user *)(instruction_pointer(regs) - 4); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | |
| 118 | /* |
| 119 | * This is the same as NWFPE, because it's not clear what |
| 120 | * this is used for |
| 121 | */ |
| 122 | current->thread.error_code = 0; |
| 123 | current->thread.trap_no = 6; |
| 124 | |
Russell King | da41119 | 2005-06-29 23:02:02 +0100 | [diff] [blame] | 125 | send_sig_info(SIGFPE, &info, current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | } |
| 127 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 128 | static void vfp_panic(char *reason, u32 inst) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | { |
| 130 | int i; |
| 131 | |
| 132 | printk(KERN_ERR "VFP: Error: %s\n", reason); |
| 133 | printk(KERN_ERR "VFP: EXC 0x%08x SCR 0x%08x INST 0x%08x\n", |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 134 | fmrx(FPEXC), fmrx(FPSCR), inst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | for (i = 0; i < 32; i += 2) |
| 136 | printk(KERN_ERR "VFP: s%2u: 0x%08x s%2u: 0x%08x\n", |
| 137 | i, vfp_get_float(i), i+1, vfp_get_float(i+1)); |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * Process bitmask of exception conditions. |
| 142 | */ |
| 143 | static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_regs *regs) |
| 144 | { |
| 145 | int si_code = 0; |
| 146 | |
| 147 | pr_debug("VFP: raising exceptions %08x\n", exceptions); |
| 148 | |
Daniel Jacobowitz | 7c6f251 | 2006-08-27 12:42:08 +0100 | [diff] [blame] | 149 | if (exceptions == VFP_EXCEPTION_ERROR) { |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 150 | vfp_panic("unhandled bounce", inst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | vfp_raise_sigfpe(0, regs); |
| 152 | return; |
| 153 | } |
| 154 | |
| 155 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 156 | * Update the FPSCR with the additional exception flags. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | * Comparison instructions always return at least one of |
| 158 | * these flags set. |
| 159 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | fpscr |= exceptions; |
| 161 | |
| 162 | fmxr(FPSCR, fpscr); |
| 163 | |
| 164 | #define RAISE(stat,en,sig) \ |
| 165 | if (exceptions & stat && fpscr & en) \ |
| 166 | si_code = sig; |
| 167 | |
| 168 | /* |
| 169 | * These are arranged in priority order, least to highest. |
| 170 | */ |
Takashi Ohmasa | e0f205d | 2006-10-23 11:19:40 +0100 | [diff] [blame] | 171 | RAISE(FPSCR_DZC, FPSCR_DZE, FPE_FLTDIV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | RAISE(FPSCR_IXC, FPSCR_IXE, FPE_FLTRES); |
| 173 | RAISE(FPSCR_UFC, FPSCR_UFE, FPE_FLTUND); |
| 174 | RAISE(FPSCR_OFC, FPSCR_OFE, FPE_FLTOVF); |
| 175 | RAISE(FPSCR_IOC, FPSCR_IOE, FPE_FLTINV); |
| 176 | |
| 177 | if (si_code) |
| 178 | vfp_raise_sigfpe(si_code, regs); |
| 179 | } |
| 180 | |
| 181 | /* |
| 182 | * Emulate a VFP instruction. |
| 183 | */ |
| 184 | static u32 vfp_emulate_instruction(u32 inst, u32 fpscr, struct pt_regs *regs) |
| 185 | { |
Daniel Jacobowitz | 7c6f251 | 2006-08-27 12:42:08 +0100 | [diff] [blame] | 186 | u32 exceptions = VFP_EXCEPTION_ERROR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | |
| 188 | pr_debug("VFP: emulate: INST=0x%08x SCR=0x%08x\n", inst, fpscr); |
| 189 | |
| 190 | if (INST_CPRTDO(inst)) { |
| 191 | if (!INST_CPRT(inst)) { |
| 192 | /* |
| 193 | * CPDO |
| 194 | */ |
| 195 | if (vfp_single(inst)) { |
| 196 | exceptions = vfp_single_cpdo(inst, fpscr); |
| 197 | } else { |
| 198 | exceptions = vfp_double_cpdo(inst, fpscr); |
| 199 | } |
| 200 | } else { |
| 201 | /* |
| 202 | * A CPRT instruction can not appear in FPINST2, nor |
| 203 | * can it cause an exception. Therefore, we do not |
| 204 | * have to emulate it. |
| 205 | */ |
| 206 | } |
| 207 | } else { |
| 208 | /* |
| 209 | * A CPDT instruction can not appear in FPINST2, nor can |
| 210 | * it cause an exception. Therefore, we do not have to |
| 211 | * emulate it. |
| 212 | */ |
| 213 | } |
Russell King | 928bd1b | 2006-04-25 20:41:27 +0100 | [diff] [blame] | 214 | return exceptions & ~VFP_NAN_FLAG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | } |
| 216 | |
| 217 | /* |
| 218 | * Package up a bounce condition. |
| 219 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 220 | void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | { |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 222 | u32 fpscr, orig_fpscr, fpsid, exceptions; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | |
| 224 | pr_debug("VFP: bounce: trigger %08x fpexc %08x\n", trigger, fpexc); |
| 225 | |
| 226 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 227 | * At this point, FPEXC can have the following configuration: |
| 228 | * |
| 229 | * EX DEX IXE |
| 230 | * 0 1 x - synchronous exception |
| 231 | * 1 x 0 - asynchronous exception |
| 232 | * 1 x 1 - sychronous on VFP subarch 1 and asynchronous on later |
| 233 | * 0 0 1 - synchronous on VFP9 (non-standard subarch 1 |
| 234 | * implementation), undefined otherwise |
| 235 | * |
| 236 | * Clear various bits and enable access to the VFP so we can |
| 237 | * handle the bounce. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 239 | fmxr(FPEXC, fpexc & ~(FPEXC_EX|FPEXC_DEX|FPEXC_FP2V|FPEXC_VV|FPEXC_TRAP_MASK)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 241 | fpsid = fmrx(FPSID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | orig_fpscr = fpscr = fmrx(FPSCR); |
| 243 | |
| 244 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 245 | * Check for the special VFP subarch 1 and FPSCR.IXE bit case |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 247 | if ((fpsid & FPSID_ARCH_MASK) == (1 << FPSID_ARCH_BIT) |
| 248 | && (fpscr & FPSCR_IXE)) { |
| 249 | /* |
| 250 | * Synchronous exception, emulate the trigger instruction |
| 251 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | goto emulate; |
| 253 | } |
| 254 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 255 | if (fpexc & FPEXC_EX) { |
| 256 | /* |
| 257 | * Asynchronous exception. The instruction is read from FPINST |
| 258 | * and the interrupted instruction has to be restarted. |
| 259 | */ |
| 260 | trigger = fmrx(FPINST); |
| 261 | regs->ARM_pc -= 4; |
| 262 | } else if (!(fpexc & FPEXC_DEX)) { |
| 263 | /* |
| 264 | * Illegal combination of bits. It can be caused by an |
| 265 | * unallocated VFP instruction but with FPSCR.IXE set and not |
| 266 | * on VFP subarch 1. |
| 267 | */ |
| 268 | vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr, regs); |
| 269 | return; |
| 270 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | |
| 272 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 273 | * Modify fpscr to indicate the number of iterations remaining. |
| 274 | * If FPEXC.EX is 0, FPEXC.DEX is 1 and the FPEXC.VV bit indicates |
| 275 | * whether FPEXC.VECITR or FPSCR.LEN is used. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 277 | if (fpexc & (FPEXC_EX | FPEXC_VV)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | u32 len; |
| 279 | |
| 280 | len = fpexc + (1 << FPEXC_LENGTH_BIT); |
| 281 | |
| 282 | fpscr &= ~FPSCR_LENGTH_MASK; |
| 283 | fpscr |= (len & FPEXC_LENGTH_MASK) << (FPSCR_LENGTH_BIT - FPEXC_LENGTH_BIT); |
| 284 | } |
| 285 | |
| 286 | /* |
| 287 | * Handle the first FP instruction. We used to take note of the |
| 288 | * FPEXC bounce reason, but this appears to be unreliable. |
| 289 | * Emulate the bounced instruction instead. |
| 290 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 291 | exceptions = vfp_emulate_instruction(trigger, fpscr, regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | if (exceptions) |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 293 | vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | |
| 295 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 296 | * If there isn't a second FP instruction, exit now. Note that |
| 297 | * the FPEXC.FP2V bit is valid only if FPEXC.EX is 1. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 299 | if (fpexc ^ (FPEXC_EX | FPEXC_FP2V)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | return; |
| 301 | |
| 302 | /* |
| 303 | * The barrier() here prevents fpinst2 being read |
| 304 | * before the condition above. |
| 305 | */ |
| 306 | barrier(); |
| 307 | trigger = fmrx(FPINST2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 308 | |
| 309 | emulate: |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 310 | exceptions = vfp_emulate_instruction(trigger, orig_fpscr, regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | if (exceptions) |
| 312 | vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs); |
| 313 | } |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 314 | |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 315 | static void vfp_enable(void *unused) |
| 316 | { |
| 317 | u32 access = get_copro_access(); |
| 318 | |
| 319 | /* |
| 320 | * Enable full access to VFP (cp10 and cp11) |
| 321 | */ |
| 322 | set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11)); |
| 323 | } |
| 324 | |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 325 | #ifdef CONFIG_PM |
| 326 | #include <linux/sysdev.h> |
| 327 | |
| 328 | static int vfp_pm_suspend(struct sys_device *dev, pm_message_t state) |
| 329 | { |
| 330 | struct thread_info *ti = current_thread_info(); |
| 331 | u32 fpexc = fmrx(FPEXC); |
| 332 | |
| 333 | /* if vfp is on, then save state for resumption */ |
| 334 | if (fpexc & FPEXC_EN) { |
| 335 | printk(KERN_DEBUG "%s: saving vfp state\n", __func__); |
| 336 | vfp_save_state(&ti->vfpstate, fpexc); |
| 337 | |
| 338 | /* disable, just in case */ |
| 339 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
| 340 | } |
| 341 | |
| 342 | /* clear any information we had about last context state */ |
| 343 | memset(last_VFP_context, 0, sizeof(last_VFP_context)); |
| 344 | |
| 345 | return 0; |
| 346 | } |
| 347 | |
| 348 | static int vfp_pm_resume(struct sys_device *dev) |
| 349 | { |
| 350 | /* ensure we have access to the vfp */ |
| 351 | vfp_enable(NULL); |
| 352 | |
| 353 | /* and disable it to ensure the next usage restores the state */ |
| 354 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
| 355 | |
| 356 | return 0; |
| 357 | } |
| 358 | |
| 359 | static struct sysdev_class vfp_pm_sysclass = { |
| 360 | .name = "vfp", |
| 361 | .suspend = vfp_pm_suspend, |
| 362 | .resume = vfp_pm_resume, |
| 363 | }; |
| 364 | |
| 365 | static struct sys_device vfp_pm_sysdev = { |
| 366 | .cls = &vfp_pm_sysclass, |
| 367 | }; |
| 368 | |
| 369 | static void vfp_pm_init(void) |
| 370 | { |
| 371 | sysdev_class_register(&vfp_pm_sysclass); |
| 372 | sysdev_register(&vfp_pm_sysdev); |
| 373 | } |
| 374 | |
| 375 | |
| 376 | #else |
| 377 | static inline void vfp_pm_init(void) { } |
| 378 | #endif /* CONFIG_PM */ |
| 379 | |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame^] | 380 | /* |
| 381 | * Synchronise the hardware VFP state of a thread other than current with the |
| 382 | * saved one. This function is used by the ptrace mechanism. |
| 383 | */ |
| 384 | #ifdef CONFIG_SMP |
| 385 | void vfp_sync_state(struct thread_info *thread) |
| 386 | { |
| 387 | /* |
| 388 | * On SMP systems, the VFP state is automatically saved at every |
| 389 | * context switch. We mark the thread VFP state as belonging to a |
| 390 | * non-existent CPU so that the saved one will be reloaded when |
| 391 | * needed. |
| 392 | */ |
| 393 | thread->vfpstate.hard.cpu = NR_CPUS; |
| 394 | } |
| 395 | #else |
| 396 | void vfp_sync_state(struct thread_info *thread) |
| 397 | { |
| 398 | unsigned int cpu = get_cpu(); |
| 399 | u32 fpexc = fmrx(FPEXC); |
| 400 | |
| 401 | /* |
| 402 | * If VFP is enabled, the previous state was already saved and |
| 403 | * last_VFP_context updated. |
| 404 | */ |
| 405 | if (fpexc & FPEXC_EN) |
| 406 | goto out; |
| 407 | |
| 408 | if (!last_VFP_context[cpu]) |
| 409 | goto out; |
| 410 | |
| 411 | /* |
| 412 | * Save the last VFP state on this CPU. |
| 413 | */ |
| 414 | fmxr(FPEXC, fpexc | FPEXC_EN); |
| 415 | vfp_save_state(last_VFP_context[cpu], fpexc); |
| 416 | fmxr(FPEXC, fpexc); |
| 417 | |
| 418 | /* |
| 419 | * Set the context to NULL to force a reload the next time the thread |
| 420 | * uses the VFP. |
| 421 | */ |
| 422 | last_VFP_context[cpu] = NULL; |
| 423 | |
| 424 | out: |
| 425 | put_cpu(); |
| 426 | } |
| 427 | #endif |
| 428 | |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 429 | #include <linux/smp.h> |
| 430 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | /* |
| 432 | * VFP support code initialisation. |
| 433 | */ |
| 434 | static int __init vfp_init(void) |
| 435 | { |
| 436 | unsigned int vfpsid; |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 437 | unsigned int cpu_arch = cpu_architecture(); |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 438 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 439 | if (cpu_arch >= CPU_ARCH_ARMv6) |
| 440 | vfp_enable(NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | |
| 442 | /* |
| 443 | * First check that there is a VFP that we can use. |
| 444 | * The handler is already setup to just log calls, so |
| 445 | * we just need to read the VFPSID register. |
| 446 | */ |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 447 | vfp_vector = vfp_testing_entry; |
Tzachi Perelstein | b9338a7 | 2007-09-09 14:24:59 +0100 | [diff] [blame] | 448 | barrier(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | vfpsid = fmrx(FPSID); |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 450 | barrier(); |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 451 | vfp_vector = vfp_null_entry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | |
| 453 | printk(KERN_INFO "VFP support v0.3: "); |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 454 | if (VFP_arch) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | printk("not present\n"); |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 456 | else if (vfpsid & FPSID_NODOUBLE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | printk("no double precision support\n"); |
| 458 | } else { |
Jens Axboe | 8691e5a | 2008-06-06 11:18:06 +0200 | [diff] [blame] | 459 | smp_call_function(vfp_enable, NULL, 1); |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 460 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | VFP_arch = (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT; /* Extract the architecture version */ |
| 462 | printk("implementor %02x architecture %d part %02x variant %x rev %x\n", |
| 463 | (vfpsid & FPSID_IMPLEMENTER_MASK) >> FPSID_IMPLEMENTER_BIT, |
| 464 | (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT, |
| 465 | (vfpsid & FPSID_PART_MASK) >> FPSID_PART_BIT, |
| 466 | (vfpsid & FPSID_VARIANT_MASK) >> FPSID_VARIANT_BIT, |
| 467 | (vfpsid & FPSID_REV_MASK) >> FPSID_REV_BIT); |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 468 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | vfp_vector = vfp_support_entry; |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 470 | |
| 471 | thread_register_notifier(&vfp_notifier_block); |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 472 | vfp_pm_init(); |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 473 | |
| 474 | /* |
| 475 | * We detected VFP, and the support code is |
| 476 | * in place; report VFP support to userspace. |
| 477 | */ |
| 478 | elf_hwcap |= HWCAP_VFP; |
Catalin Marinas | 2bedbdf | 2008-11-06 13:23:07 +0000 | [diff] [blame] | 479 | #ifdef CONFIG_NEON |
| 480 | /* |
| 481 | * Check for the presence of the Advanced SIMD |
| 482 | * load/store instructions, integer and single |
| 483 | * precision floating point operations. |
| 484 | */ |
| 485 | if ((fmrx(MVFR1) & 0x000fff00) == 0x00011100) |
| 486 | elf_hwcap |= HWCAP_NEON; |
| 487 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 488 | } |
| 489 | return 0; |
| 490 | } |
| 491 | |
| 492 | late_initcall(vfp_init); |