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 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/types.h> |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 12 | #include <linux/cpu.h> |
Colin Cross | 746a9d1 | 2011-02-10 02:08:32 -0800 | [diff] [blame] | 13 | #include <linux/cpu_pm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/kernel.h> |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 15 | #include <linux/notifier.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/signal.h> |
| 17 | #include <linux/sched.h> |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 18 | #include <linux/smp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <linux/init.h> |
Will Deacon | 2498814 | 2012-04-23 15:38:28 +0100 | [diff] [blame] | 20 | #include <linux/uaccess.h> |
| 21 | #include <linux/user.h> |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 22 | |
Russell King | 15d07dc | 2012-03-28 18:30:01 +0100 | [diff] [blame] | 23 | #include <asm/cp15.h> |
Tony Lindgren | 5aaf254 | 2010-07-01 13:41:05 +0100 | [diff] [blame] | 24 | #include <asm/cputype.h> |
David Howells | 9f97da7 | 2012-03-28 18:30:01 +0100 | [diff] [blame] | 25 | #include <asm/system_info.h> |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 26 | #include <asm/thread_notify.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <asm/vfp.h> |
| 28 | |
| 29 | #include "vfpinstr.h" |
| 30 | #include "vfp.h" |
| 31 | |
| 32 | /* |
| 33 | * Our undef handlers (in entry.S) |
| 34 | */ |
| 35 | void vfp_testing_entry(void); |
| 36 | void vfp_support_entry(void); |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 37 | void vfp_null_entry(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 39 | void (*vfp_vector)(void) = vfp_null_entry; |
Russell King | af61bdf | 2011-07-09 13:44:04 +0100 | [diff] [blame] | 40 | |
| 41 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | * Dual-use variable. |
| 43 | * Used in startup: set to non-zero if VFP checks fail |
| 44 | * After startup, holds VFP architecture |
| 45 | */ |
| 46 | unsigned int VFP_arch; |
| 47 | |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 48 | /* |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 49 | * The pointer to the vfpstate structure of the thread which currently |
| 50 | * owns the context held in the VFP hardware, or NULL if the hardware |
| 51 | * context is invalid. |
| 52 | * |
| 53 | * For UP, this is sufficient to tell which thread owns the VFP context. |
| 54 | * However, for SMP, we also need to check the CPU number stored in the |
| 55 | * saved state too to catch migrations. |
| 56 | */ |
| 57 | union vfp_state *vfp_current_hw_state[NR_CPUS]; |
| 58 | |
| 59 | /* |
| 60 | * Is 'thread's most up to date state stored in this CPUs hardware? |
| 61 | * Must be called from non-preemptible context. |
| 62 | */ |
| 63 | static bool vfp_state_in_hw(unsigned int cpu, struct thread_info *thread) |
| 64 | { |
| 65 | #ifdef CONFIG_SMP |
| 66 | if (thread->vfpstate.hard.cpu != cpu) |
| 67 | return false; |
| 68 | #endif |
| 69 | return vfp_current_hw_state[cpu] == &thread->vfpstate; |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * Force a reload of the VFP context from the thread structure. We do |
| 74 | * this by ensuring that access to the VFP hardware is disabled, and |
Santosh Shilimkar | 48af9fe | 2011-09-02 21:12:36 +0530 | [diff] [blame] | 75 | * clear vfp_current_hw_state. Must be called from non-preemptible context. |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 76 | */ |
| 77 | static void vfp_force_reload(unsigned int cpu, struct thread_info *thread) |
| 78 | { |
| 79 | if (vfp_state_in_hw(cpu, thread)) { |
| 80 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
| 81 | vfp_current_hw_state[cpu] = NULL; |
| 82 | } |
| 83 | #ifdef CONFIG_SMP |
| 84 | thread->vfpstate.hard.cpu = NR_CPUS; |
| 85 | #endif |
| 86 | } |
| 87 | |
| 88 | /* |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 89 | * Per-thread VFP initialization. |
| 90 | */ |
| 91 | static void vfp_thread_flush(struct thread_info *thread) |
| 92 | { |
| 93 | union vfp_state *vfp = &thread->vfpstate; |
| 94 | unsigned int cpu; |
| 95 | |
Russell King | 19dad35 | 2011-07-09 17:41:33 +0100 | [diff] [blame] | 96 | /* |
| 97 | * Disable VFP to ensure we initialize it first. We must ensure |
| 98 | * that the modification of vfp_current_hw_state[] and hardware |
| 99 | * disable are done for the same CPU and without preemption. |
| 100 | * |
| 101 | * Do this first to ensure that preemption won't overwrite our |
| 102 | * state saving should access to the VFP be enabled at this point. |
| 103 | */ |
| 104 | cpu = get_cpu(); |
| 105 | if (vfp_current_hw_state[cpu] == vfp) |
| 106 | vfp_current_hw_state[cpu] = NULL; |
| 107 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
| 108 | put_cpu(); |
| 109 | |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 110 | memset(vfp, 0, sizeof(union vfp_state)); |
| 111 | |
| 112 | vfp->hard.fpexc = FPEXC_EN; |
| 113 | vfp->hard.fpscr = FPSCR_ROUND_NEAREST; |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 114 | #ifdef CONFIG_SMP |
| 115 | vfp->hard.cpu = NR_CPUS; |
| 116 | #endif |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 117 | } |
| 118 | |
Russell King | 797245f | 2009-12-18 14:34:43 +0000 | [diff] [blame] | 119 | static void vfp_thread_exit(struct thread_info *thread) |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 120 | { |
| 121 | /* release case: Per-thread VFP cleanup. */ |
| 122 | union vfp_state *vfp = &thread->vfpstate; |
Russell King | 797245f | 2009-12-18 14:34:43 +0000 | [diff] [blame] | 123 | unsigned int cpu = get_cpu(); |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 124 | |
Russell King | af61bdf | 2011-07-09 13:44:04 +0100 | [diff] [blame] | 125 | if (vfp_current_hw_state[cpu] == vfp) |
| 126 | vfp_current_hw_state[cpu] = NULL; |
Russell King | 797245f | 2009-12-18 14:34:43 +0000 | [diff] [blame] | 127 | put_cpu(); |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 128 | } |
| 129 | |
Catalin Marinas | c98c097 | 2011-04-06 16:17:17 +0100 | [diff] [blame] | 130 | static void vfp_thread_copy(struct thread_info *thread) |
| 131 | { |
| 132 | struct thread_info *parent = current_thread_info(); |
| 133 | |
| 134 | vfp_sync_hwstate(parent); |
| 135 | thread->vfpstate = parent->vfpstate; |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 136 | #ifdef CONFIG_SMP |
| 137 | thread->vfpstate.hard.cpu = NR_CPUS; |
| 138 | #endif |
Catalin Marinas | c98c097 | 2011-04-06 16:17:17 +0100 | [diff] [blame] | 139 | } |
| 140 | |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 141 | /* |
| 142 | * When this function is called with the following 'cmd's, the following |
| 143 | * is true while this function is being run: |
| 144 | * THREAD_NOFTIFY_SWTICH: |
| 145 | * - the previously running thread will not be scheduled onto another CPU. |
| 146 | * - the next thread to be run (v) will not be running on another CPU. |
| 147 | * - thread->cpu is the local CPU number |
| 148 | * - not preemptible as we're called in the middle of a thread switch |
| 149 | * THREAD_NOTIFY_FLUSH: |
| 150 | * - the thread (v) will be running on the local CPU, so |
| 151 | * v === current_thread_info() |
| 152 | * - thread->cpu is the local CPU number at the time it is accessed, |
| 153 | * but may change at any time. |
| 154 | * - we could be preempted if tree preempt rcu is enabled, so |
| 155 | * it is unsafe to use thread->cpu. |
Russell King | 797245f | 2009-12-18 14:34:43 +0000 | [diff] [blame] | 156 | * THREAD_NOTIFY_EXIT |
| 157 | * - the thread (v) will be running on the local CPU, so |
| 158 | * v === current_thread_info() |
| 159 | * - thread->cpu is the local CPU number at the time it is accessed, |
| 160 | * but may change at any time. |
| 161 | * - we could be preempted if tree preempt rcu is enabled, so |
| 162 | * it is unsafe to use thread->cpu. |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 163 | */ |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 164 | 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] | 165 | { |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 166 | struct thread_info *thread = v; |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 167 | u32 fpexc; |
| 168 | #ifdef CONFIG_SMP |
| 169 | unsigned int cpu; |
| 170 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 172 | switch (cmd) { |
| 173 | case THREAD_NOTIFY_SWITCH: |
| 174 | fpexc = fmrx(FPEXC); |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 175 | |
| 176 | #ifdef CONFIG_SMP |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 177 | cpu = thread->cpu; |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 178 | |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 179 | /* |
| 180 | * On SMP, if VFP is enabled, save the old state in |
| 181 | * case the thread migrates to a different CPU. The |
| 182 | * restoring is done lazily. |
| 183 | */ |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 184 | if ((fpexc & FPEXC_EN) && vfp_current_hw_state[cpu]) |
Russell King | af61bdf | 2011-07-09 13:44:04 +0100 | [diff] [blame] | 185 | vfp_save_state(vfp_current_hw_state[cpu], fpexc); |
Catalin Marinas | c642846 | 2007-01-24 18:47:08 +0100 | [diff] [blame] | 186 | #endif |
| 187 | |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 188 | /* |
| 189 | * Always disable VFP so we can lazily save/restore the |
| 190 | * old state. |
| 191 | */ |
Russell King | 228adef | 2007-07-18 09:37:10 +0100 | [diff] [blame] | 192 | fmxr(FPEXC, fpexc & ~FPEXC_EN); |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 193 | break; |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 194 | |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 195 | case THREAD_NOTIFY_FLUSH: |
Russell King | 0d782dc | 2009-12-12 14:47:40 +0000 | [diff] [blame] | 196 | vfp_thread_flush(thread); |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 197 | break; |
| 198 | |
| 199 | case THREAD_NOTIFY_EXIT: |
Russell King | 797245f | 2009-12-18 14:34:43 +0000 | [diff] [blame] | 200 | vfp_thread_exit(thread); |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 201 | break; |
Catalin Marinas | c98c097 | 2011-04-06 16:17:17 +0100 | [diff] [blame] | 202 | |
| 203 | case THREAD_NOTIFY_COPY: |
| 204 | vfp_thread_copy(thread); |
| 205 | break; |
Catalin Marinas | 2e82669a | 2011-04-06 16:16:29 +0100 | [diff] [blame] | 206 | } |
Russell King | 681a499 | 2006-08-27 12:38:34 +0100 | [diff] [blame] | 207 | |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 208 | return NOTIFY_DONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | } |
| 210 | |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 211 | static struct notifier_block vfp_notifier_block = { |
| 212 | .notifier_call = vfp_notifier, |
| 213 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | |
| 215 | /* |
| 216 | * Raise a SIGFPE for the current process. |
| 217 | * sicode describes the signal being raised. |
| 218 | */ |
Russell King | 2bbd7e9 | 2011-01-08 12:05:09 +0000 | [diff] [blame] | 219 | static void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | { |
| 221 | siginfo_t info; |
| 222 | |
| 223 | memset(&info, 0, sizeof(info)); |
| 224 | |
| 225 | info.si_signo = SIGFPE; |
| 226 | info.si_code = sicode; |
Al Viro | 35d59fc | 2006-10-11 17:22:44 +0100 | [diff] [blame] | 227 | info.si_addr = (void __user *)(instruction_pointer(regs) - 4); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | |
| 229 | /* |
| 230 | * This is the same as NWFPE, because it's not clear what |
| 231 | * this is used for |
| 232 | */ |
| 233 | current->thread.error_code = 0; |
| 234 | current->thread.trap_no = 6; |
| 235 | |
Russell King | da41119 | 2005-06-29 23:02:02 +0100 | [diff] [blame] | 236 | send_sig_info(SIGFPE, &info, current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | } |
| 238 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 239 | static void vfp_panic(char *reason, u32 inst) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | { |
| 241 | int i; |
| 242 | |
| 243 | printk(KERN_ERR "VFP: Error: %s\n", reason); |
| 244 | 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] | 245 | fmrx(FPEXC), fmrx(FPSCR), inst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | for (i = 0; i < 32; i += 2) |
| 247 | printk(KERN_ERR "VFP: s%2u: 0x%08x s%2u: 0x%08x\n", |
| 248 | i, vfp_get_float(i), i+1, vfp_get_float(i+1)); |
| 249 | } |
| 250 | |
| 251 | /* |
| 252 | * Process bitmask of exception conditions. |
| 253 | */ |
| 254 | static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_regs *regs) |
| 255 | { |
| 256 | int si_code = 0; |
| 257 | |
| 258 | pr_debug("VFP: raising exceptions %08x\n", exceptions); |
| 259 | |
Daniel Jacobowitz | 7c6f251 | 2006-08-27 12:42:08 +0100 | [diff] [blame] | 260 | if (exceptions == VFP_EXCEPTION_ERROR) { |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 261 | vfp_panic("unhandled bounce", inst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 262 | vfp_raise_sigfpe(0, regs); |
| 263 | return; |
| 264 | } |
| 265 | |
| 266 | /* |
Catalin Marinas | dbead40 | 2010-02-01 18:50:40 +0100 | [diff] [blame] | 267 | * If any of the status flags are set, update the FPSCR. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | * Comparison instructions always return at least one of |
| 269 | * these flags set. |
| 270 | */ |
Catalin Marinas | dbead40 | 2010-02-01 18:50:40 +0100 | [diff] [blame] | 271 | if (exceptions & (FPSCR_N|FPSCR_Z|FPSCR_C|FPSCR_V)) |
| 272 | fpscr &= ~(FPSCR_N|FPSCR_Z|FPSCR_C|FPSCR_V); |
| 273 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | fpscr |= exceptions; |
| 275 | |
| 276 | fmxr(FPSCR, fpscr); |
| 277 | |
| 278 | #define RAISE(stat,en,sig) \ |
| 279 | if (exceptions & stat && fpscr & en) \ |
| 280 | si_code = sig; |
| 281 | |
| 282 | /* |
| 283 | * These are arranged in priority order, least to highest. |
| 284 | */ |
Takashi Ohmasa | e0f205d | 2006-10-23 11:19:40 +0100 | [diff] [blame] | 285 | RAISE(FPSCR_DZC, FPSCR_DZE, FPE_FLTDIV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | RAISE(FPSCR_IXC, FPSCR_IXE, FPE_FLTRES); |
| 287 | RAISE(FPSCR_UFC, FPSCR_UFE, FPE_FLTUND); |
| 288 | RAISE(FPSCR_OFC, FPSCR_OFE, FPE_FLTOVF); |
| 289 | RAISE(FPSCR_IOC, FPSCR_IOE, FPE_FLTINV); |
| 290 | |
| 291 | if (si_code) |
| 292 | vfp_raise_sigfpe(si_code, regs); |
| 293 | } |
| 294 | |
| 295 | /* |
| 296 | * Emulate a VFP instruction. |
| 297 | */ |
| 298 | static u32 vfp_emulate_instruction(u32 inst, u32 fpscr, struct pt_regs *regs) |
| 299 | { |
Daniel Jacobowitz | 7c6f251 | 2006-08-27 12:42:08 +0100 | [diff] [blame] | 300 | u32 exceptions = VFP_EXCEPTION_ERROR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | |
| 302 | pr_debug("VFP: emulate: INST=0x%08x SCR=0x%08x\n", inst, fpscr); |
| 303 | |
| 304 | if (INST_CPRTDO(inst)) { |
| 305 | if (!INST_CPRT(inst)) { |
| 306 | /* |
| 307 | * CPDO |
| 308 | */ |
| 309 | if (vfp_single(inst)) { |
| 310 | exceptions = vfp_single_cpdo(inst, fpscr); |
| 311 | } else { |
| 312 | exceptions = vfp_double_cpdo(inst, fpscr); |
| 313 | } |
| 314 | } else { |
| 315 | /* |
| 316 | * A CPRT instruction can not appear in FPINST2, nor |
| 317 | * can it cause an exception. Therefore, we do not |
| 318 | * have to emulate it. |
| 319 | */ |
| 320 | } |
| 321 | } else { |
| 322 | /* |
| 323 | * A CPDT instruction can not appear in FPINST2, nor can |
| 324 | * it cause an exception. Therefore, we do not have to |
| 325 | * emulate it. |
| 326 | */ |
| 327 | } |
Russell King | 928bd1b | 2006-04-25 20:41:27 +0100 | [diff] [blame] | 328 | return exceptions & ~VFP_NAN_FLAG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | } |
| 330 | |
| 331 | /* |
| 332 | * Package up a bounce condition. |
| 333 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 334 | void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | { |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 336 | u32 fpscr, orig_fpscr, fpsid, exceptions; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | |
| 338 | pr_debug("VFP: bounce: trigger %08x fpexc %08x\n", trigger, fpexc); |
| 339 | |
| 340 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 341 | * At this point, FPEXC can have the following configuration: |
| 342 | * |
| 343 | * EX DEX IXE |
| 344 | * 0 1 x - synchronous exception |
| 345 | * 1 x 0 - asynchronous exception |
| 346 | * 1 x 1 - sychronous on VFP subarch 1 and asynchronous on later |
| 347 | * 0 0 1 - synchronous on VFP9 (non-standard subarch 1 |
| 348 | * implementation), undefined otherwise |
| 349 | * |
| 350 | * Clear various bits and enable access to the VFP so we can |
| 351 | * handle the bounce. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 353 | 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] | 354 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 355 | fpsid = fmrx(FPSID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | orig_fpscr = fpscr = fmrx(FPSCR); |
| 357 | |
| 358 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 359 | * Check for the special VFP subarch 1 and FPSCR.IXE bit case |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 361 | if ((fpsid & FPSID_ARCH_MASK) == (1 << FPSID_ARCH_BIT) |
| 362 | && (fpscr & FPSCR_IXE)) { |
| 363 | /* |
| 364 | * Synchronous exception, emulate the trigger instruction |
| 365 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | goto emulate; |
| 367 | } |
| 368 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 369 | if (fpexc & FPEXC_EX) { |
Catalin Marinas | 85d6943 | 2009-05-30 14:00:18 +0100 | [diff] [blame] | 370 | #ifndef CONFIG_CPU_FEROCEON |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 371 | /* |
| 372 | * Asynchronous exception. The instruction is read from FPINST |
| 373 | * and the interrupted instruction has to be restarted. |
| 374 | */ |
| 375 | trigger = fmrx(FPINST); |
| 376 | regs->ARM_pc -= 4; |
Catalin Marinas | 85d6943 | 2009-05-30 14:00:18 +0100 | [diff] [blame] | 377 | #endif |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 378 | } else if (!(fpexc & FPEXC_DEX)) { |
| 379 | /* |
| 380 | * Illegal combination of bits. It can be caused by an |
| 381 | * unallocated VFP instruction but with FPSCR.IXE set and not |
| 382 | * on VFP subarch 1. |
| 383 | */ |
| 384 | vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr, regs); |
George G. Davis | f2255be | 2009-04-01 20:27:18 +0100 | [diff] [blame] | 385 | goto exit; |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 386 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | |
| 388 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 389 | * Modify fpscr to indicate the number of iterations remaining. |
| 390 | * If FPEXC.EX is 0, FPEXC.DEX is 1 and the FPEXC.VV bit indicates |
| 391 | * whether FPEXC.VECITR or FPSCR.LEN is used. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 393 | if (fpexc & (FPEXC_EX | FPEXC_VV)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | u32 len; |
| 395 | |
| 396 | len = fpexc + (1 << FPEXC_LENGTH_BIT); |
| 397 | |
| 398 | fpscr &= ~FPSCR_LENGTH_MASK; |
| 399 | fpscr |= (len & FPEXC_LENGTH_MASK) << (FPSCR_LENGTH_BIT - FPEXC_LENGTH_BIT); |
| 400 | } |
| 401 | |
| 402 | /* |
| 403 | * Handle the first FP instruction. We used to take note of the |
| 404 | * FPEXC bounce reason, but this appears to be unreliable. |
| 405 | * Emulate the bounced instruction instead. |
| 406 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 407 | exceptions = vfp_emulate_instruction(trigger, fpscr, regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | if (exceptions) |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 409 | vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | |
| 411 | /* |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 412 | * If there isn't a second FP instruction, exit now. Note that |
| 413 | * the FPEXC.FP2V bit is valid only if FPEXC.EX is 1. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 414 | */ |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 415 | if (fpexc ^ (FPEXC_EX | FPEXC_FP2V)) |
George G. Davis | f2255be | 2009-04-01 20:27:18 +0100 | [diff] [blame] | 416 | goto exit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | |
| 418 | /* |
| 419 | * The barrier() here prevents fpinst2 being read |
| 420 | * before the condition above. |
| 421 | */ |
| 422 | barrier(); |
| 423 | trigger = fmrx(FPINST2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | |
| 425 | emulate: |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 426 | exceptions = vfp_emulate_instruction(trigger, orig_fpscr, regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | if (exceptions) |
| 428 | vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs); |
George G. Davis | f2255be | 2009-04-01 20:27:18 +0100 | [diff] [blame] | 429 | exit: |
| 430 | preempt_enable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | } |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 432 | |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 433 | static void vfp_enable(void *unused) |
| 434 | { |
| 435 | u32 access = get_copro_access(); |
| 436 | |
| 437 | /* |
| 438 | * Enable full access to VFP (cp10 and cp11) |
| 439 | */ |
| 440 | set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11)); |
| 441 | } |
| 442 | |
Colin Cross | 746a9d1 | 2011-02-10 02:08:32 -0800 | [diff] [blame] | 443 | #ifdef CONFIG_CPU_PM |
Rafael J. Wysocki | 328f5cc | 2011-04-22 22:02:33 +0200 | [diff] [blame] | 444 | static int vfp_pm_suspend(void) |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 445 | { |
| 446 | struct thread_info *ti = current_thread_info(); |
| 447 | u32 fpexc = fmrx(FPEXC); |
| 448 | |
| 449 | /* if vfp is on, then save state for resumption */ |
| 450 | if (fpexc & FPEXC_EN) { |
| 451 | printk(KERN_DEBUG "%s: saving vfp state\n", __func__); |
| 452 | vfp_save_state(&ti->vfpstate, fpexc); |
| 453 | |
| 454 | /* disable, just in case */ |
| 455 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
| 456 | } |
| 457 | |
| 458 | /* clear any information we had about last context state */ |
Russell King | af61bdf | 2011-07-09 13:44:04 +0100 | [diff] [blame] | 459 | memset(vfp_current_hw_state, 0, sizeof(vfp_current_hw_state)); |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 460 | |
| 461 | return 0; |
| 462 | } |
| 463 | |
Rafael J. Wysocki | 328f5cc | 2011-04-22 22:02:33 +0200 | [diff] [blame] | 464 | static void vfp_pm_resume(void) |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 465 | { |
| 466 | /* ensure we have access to the vfp */ |
| 467 | vfp_enable(NULL); |
| 468 | |
| 469 | /* and disable it to ensure the next usage restores the state */ |
| 470 | fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 471 | } |
| 472 | |
Colin Cross | 746a9d1 | 2011-02-10 02:08:32 -0800 | [diff] [blame] | 473 | static int vfp_cpu_pm_notifier(struct notifier_block *self, unsigned long cmd, |
| 474 | void *v) |
| 475 | { |
| 476 | switch (cmd) { |
| 477 | case CPU_PM_ENTER: |
| 478 | vfp_pm_suspend(); |
| 479 | break; |
| 480 | case CPU_PM_ENTER_FAILED: |
| 481 | case CPU_PM_EXIT: |
| 482 | vfp_pm_resume(); |
| 483 | break; |
| 484 | } |
| 485 | return NOTIFY_OK; |
| 486 | } |
| 487 | |
| 488 | static struct notifier_block vfp_cpu_pm_notifier_block = { |
| 489 | .notifier_call = vfp_cpu_pm_notifier, |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 490 | }; |
| 491 | |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 492 | static void vfp_pm_init(void) |
| 493 | { |
Colin Cross | 746a9d1 | 2011-02-10 02:08:32 -0800 | [diff] [blame] | 494 | cpu_pm_register_notifier(&vfp_cpu_pm_notifier_block); |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 495 | } |
| 496 | |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 497 | #else |
| 498 | static inline void vfp_pm_init(void) { } |
Colin Cross | 746a9d1 | 2011-02-10 02:08:32 -0800 | [diff] [blame] | 499 | #endif /* CONFIG_CPU_PM */ |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 500 | |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 501 | /* |
| 502 | * Ensure that the VFP state stored in 'thread->vfpstate' is up to date |
| 503 | * with the hardware state. |
| 504 | */ |
Russell King | ad187f9 | 2010-02-06 11:36:23 +0000 | [diff] [blame] | 505 | void vfp_sync_hwstate(struct thread_info *thread) |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 506 | { |
| 507 | unsigned int cpu = get_cpu(); |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 508 | |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 509 | if (vfp_state_in_hw(cpu, thread)) { |
Russell King | 54cb3db | 2010-02-06 11:27:45 +0000 | [diff] [blame] | 510 | u32 fpexc = fmrx(FPEXC); |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 511 | |
Russell King | 54cb3db | 2010-02-06 11:27:45 +0000 | [diff] [blame] | 512 | /* |
| 513 | * Save the last VFP state on this CPU. |
| 514 | */ |
| 515 | fmxr(FPEXC, fpexc | FPEXC_EN); |
| 516 | vfp_save_state(&thread->vfpstate, fpexc | FPEXC_EN); |
Russell King | ad187f9 | 2010-02-06 11:36:23 +0000 | [diff] [blame] | 517 | fmxr(FPEXC, fpexc); |
| 518 | } |
| 519 | |
| 520 | put_cpu(); |
| 521 | } |
| 522 | |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 523 | /* Ensure that the thread reloads the hardware VFP state on the next use. */ |
Russell King | ad187f9 | 2010-02-06 11:36:23 +0000 | [diff] [blame] | 524 | void vfp_flush_hwstate(struct thread_info *thread) |
| 525 | { |
| 526 | unsigned int cpu = get_cpu(); |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 527 | |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 528 | vfp_force_reload(cpu, thread); |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 529 | |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 530 | put_cpu(); |
| 531 | } |
Catalin Marinas | 3d1228e | 2009-02-11 13:12:56 +0100 | [diff] [blame] | 532 | |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 533 | /* |
Will Deacon | 2498814 | 2012-04-23 15:38:28 +0100 | [diff] [blame] | 534 | * Save the current VFP state into the provided structures and prepare |
| 535 | * for entry into a new function (signal handler). |
| 536 | */ |
| 537 | int vfp_preserve_user_clear_hwstate(struct user_vfp __user *ufp, |
| 538 | struct user_vfp_exc __user *ufp_exc) |
| 539 | { |
| 540 | struct thread_info *thread = current_thread_info(); |
| 541 | struct vfp_hard_struct *hwstate = &thread->vfpstate.hard; |
| 542 | int err = 0; |
| 543 | |
| 544 | /* Ensure that the saved hwstate is up-to-date. */ |
| 545 | vfp_sync_hwstate(thread); |
| 546 | |
| 547 | /* |
| 548 | * Copy the floating point registers. There can be unused |
| 549 | * registers see asm/hwcap.h for details. |
| 550 | */ |
| 551 | err |= __copy_to_user(&ufp->fpregs, &hwstate->fpregs, |
| 552 | sizeof(hwstate->fpregs)); |
| 553 | /* |
| 554 | * Copy the status and control register. |
| 555 | */ |
| 556 | __put_user_error(hwstate->fpscr, &ufp->fpscr, err); |
| 557 | |
| 558 | /* |
| 559 | * Copy the exception registers. |
| 560 | */ |
| 561 | __put_user_error(hwstate->fpexc, &ufp_exc->fpexc, err); |
| 562 | __put_user_error(hwstate->fpinst, &ufp_exc->fpinst, err); |
| 563 | __put_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err); |
| 564 | |
| 565 | if (err) |
| 566 | return -EFAULT; |
Will Deacon | ff9a184 | 2012-04-23 15:42:16 +0100 | [diff] [blame] | 567 | |
| 568 | /* Ensure that VFP is disabled. */ |
| 569 | vfp_flush_hwstate(thread); |
| 570 | |
| 571 | /* |
| 572 | * As per the PCS, clear the length and stride bits for function |
| 573 | * entry. |
| 574 | */ |
| 575 | hwstate->fpscr &= ~(FPSCR_LENGTH_MASK | FPSCR_STRIDE_MASK); |
| 576 | |
| 577 | /* |
| 578 | * Disable VFP in the hwstate so that we can detect if it gets |
| 579 | * used. |
| 580 | */ |
| 581 | hwstate->fpexc &= ~FPEXC_EN; |
Will Deacon | 2498814 | 2012-04-23 15:38:28 +0100 | [diff] [blame] | 582 | return 0; |
| 583 | } |
| 584 | |
| 585 | /* Sanitise and restore the current VFP state from the provided structures. */ |
| 586 | int vfp_restore_user_hwstate(struct user_vfp __user *ufp, |
| 587 | struct user_vfp_exc __user *ufp_exc) |
| 588 | { |
| 589 | struct thread_info *thread = current_thread_info(); |
| 590 | struct vfp_hard_struct *hwstate = &thread->vfpstate.hard; |
| 591 | unsigned long fpexc; |
| 592 | int err = 0; |
| 593 | |
Will Deacon | ff9a184 | 2012-04-23 15:42:16 +0100 | [diff] [blame] | 594 | /* |
| 595 | * If VFP has been used, then disable it to avoid corrupting |
| 596 | * the new thread state. |
| 597 | */ |
| 598 | if (hwstate->fpexc & FPEXC_EN) |
| 599 | vfp_flush_hwstate(thread); |
Will Deacon | 2498814 | 2012-04-23 15:38:28 +0100 | [diff] [blame] | 600 | |
| 601 | /* |
| 602 | * Copy the floating point registers. There can be unused |
| 603 | * registers see asm/hwcap.h for details. |
| 604 | */ |
| 605 | err |= __copy_from_user(&hwstate->fpregs, &ufp->fpregs, |
| 606 | sizeof(hwstate->fpregs)); |
| 607 | /* |
| 608 | * Copy the status and control register. |
| 609 | */ |
| 610 | __get_user_error(hwstate->fpscr, &ufp->fpscr, err); |
| 611 | |
| 612 | /* |
| 613 | * Sanitise and restore the exception registers. |
| 614 | */ |
| 615 | __get_user_error(fpexc, &ufp_exc->fpexc, err); |
| 616 | |
| 617 | /* Ensure the VFP is enabled. */ |
| 618 | fpexc |= FPEXC_EN; |
| 619 | |
| 620 | /* Ensure FPINST2 is invalid and the exception flag is cleared. */ |
| 621 | fpexc &= ~(FPEXC_EX | FPEXC_FP2V); |
| 622 | hwstate->fpexc = fpexc; |
| 623 | |
| 624 | __get_user_error(hwstate->fpinst, &ufp_exc->fpinst, err); |
| 625 | __get_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err); |
| 626 | |
| 627 | return err ? -EFAULT : 0; |
| 628 | } |
| 629 | |
| 630 | /* |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 631 | * VFP hardware can lose all context when a CPU goes offline. |
Russell King | 74c25be | 2011-01-31 14:43:25 +0000 | [diff] [blame] | 632 | * As we will be running in SMP mode with CPU hotplug, we will save the |
| 633 | * hardware state at every thread switch. We clear our held state when |
| 634 | * a CPU has been killed, indicating that the VFP hardware doesn't contain |
| 635 | * a threads VFP state. When a CPU starts up, we re-enable access to the |
| 636 | * VFP hardware. |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 637 | * |
| 638 | * Both CPU_DYING and CPU_STARTING are called on the CPU which |
| 639 | * is being offlined/onlined. |
| 640 | */ |
| 641 | static int vfp_hotplug(struct notifier_block *b, unsigned long action, |
| 642 | void *hcpu) |
| 643 | { |
| 644 | if (action == CPU_DYING || action == CPU_DYING_FROZEN) { |
Russell King | f8f2a85 | 2011-07-09 16:09:43 +0100 | [diff] [blame] | 645 | vfp_force_reload((long)hcpu, current_thread_info()); |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 646 | } else if (action == CPU_STARTING || action == CPU_STARTING_FROZEN) |
| 647 | vfp_enable(NULL); |
| 648 | return NOTIFY_OK; |
| 649 | } |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 650 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 651 | /* |
| 652 | * VFP support code initialisation. |
| 653 | */ |
| 654 | static int __init vfp_init(void) |
| 655 | { |
| 656 | unsigned int vfpsid; |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 657 | unsigned int cpu_arch = cpu_architecture(); |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 658 | |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 659 | if (cpu_arch >= CPU_ARCH_ARMv6) |
| 660 | vfp_enable(NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | |
| 662 | /* |
| 663 | * First check that there is a VFP that we can use. |
| 664 | * The handler is already setup to just log calls, so |
| 665 | * we just need to read the VFPSID register. |
| 666 | */ |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 667 | vfp_vector = vfp_testing_entry; |
Tzachi Perelstein | b9338a7 | 2007-09-09 14:24:59 +0100 | [diff] [blame] | 668 | barrier(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | vfpsid = fmrx(FPSID); |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 670 | barrier(); |
Russell King | 5d4cae5 | 2007-06-10 12:22:20 +0100 | [diff] [blame] | 671 | vfp_vector = vfp_null_entry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 672 | |
| 673 | printk(KERN_INFO "VFP support v0.3: "); |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 674 | if (VFP_arch) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | printk("not present\n"); |
Catalin Marinas | c98929c | 2007-11-22 18:32:01 +0100 | [diff] [blame] | 676 | else if (vfpsid & FPSID_NODOUBLE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | printk("no double precision support\n"); |
| 678 | } else { |
Russell King | 90b4419 | 2010-12-18 10:59:49 +0000 | [diff] [blame] | 679 | hotcpu_notifier(vfp_hotplug, 0); |
| 680 | |
Jens Axboe | 8691e5a | 2008-06-06 11:18:06 +0200 | [diff] [blame] | 681 | smp_call_function(vfp_enable, NULL, 1); |
Russell King | 8e14036 | 2007-01-02 23:40:30 +0000 | [diff] [blame] | 682 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | VFP_arch = (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT; /* Extract the architecture version */ |
| 684 | printk("implementor %02x architecture %d part %02x variant %x rev %x\n", |
| 685 | (vfpsid & FPSID_IMPLEMENTER_MASK) >> FPSID_IMPLEMENTER_BIT, |
| 686 | (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT, |
| 687 | (vfpsid & FPSID_PART_MASK) >> FPSID_PART_BIT, |
| 688 | (vfpsid & FPSID_VARIANT_MASK) >> FPSID_VARIANT_BIT, |
| 689 | (vfpsid & FPSID_REV_MASK) >> FPSID_REV_BIT); |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 690 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | vfp_vector = vfp_support_entry; |
Russell King | d6551e8 | 2006-06-21 13:31:52 +0100 | [diff] [blame] | 692 | |
| 693 | thread_register_notifier(&vfp_notifier_block); |
Ben Dooks | fc0b7a2 | 2008-12-18 12:26:54 +0100 | [diff] [blame] | 694 | vfp_pm_init(); |
Russell King | efe90d2 | 2006-12-08 15:22:20 +0000 | [diff] [blame] | 695 | |
| 696 | /* |
| 697 | * We detected VFP, and the support code is |
| 698 | * in place; report VFP support to userspace. |
| 699 | */ |
| 700 | elf_hwcap |= HWCAP_VFP; |
Catalin Marinas | 7279dc3 | 2009-02-11 13:13:56 +0100 | [diff] [blame] | 701 | #ifdef CONFIG_VFPv3 |
Catalin Marinas | 325ffc3 | 2010-03-26 15:44:57 +0100 | [diff] [blame] | 702 | if (VFP_arch >= 2) { |
Catalin Marinas | 7279dc3 | 2009-02-11 13:13:56 +0100 | [diff] [blame] | 703 | elf_hwcap |= HWCAP_VFPv3; |
| 704 | |
| 705 | /* |
| 706 | * Check for VFPv3 D16. CPUs in this configuration |
| 707 | * only have 16 x 64bit registers. |
| 708 | */ |
| 709 | if (((fmrx(MVFR0) & MVFR0_A_SIMD_MASK)) == 1) |
| 710 | elf_hwcap |= HWCAP_VFPv3D16; |
| 711 | } |
| 712 | #endif |
Catalin Marinas | 2bedbdf | 2008-11-06 13:23:07 +0000 | [diff] [blame] | 713 | /* |
| 714 | * Check for the presence of the Advanced SIMD |
| 715 | * load/store instructions, integer and single |
Tony Lindgren | 5aaf254 | 2010-07-01 13:41:05 +0100 | [diff] [blame] | 716 | * precision floating point operations. Only check |
| 717 | * for NEON if the hardware has the MVFR registers. |
Catalin Marinas | 2bedbdf | 2008-11-06 13:23:07 +0000 | [diff] [blame] | 718 | */ |
Tony Lindgren | 5aaf254 | 2010-07-01 13:41:05 +0100 | [diff] [blame] | 719 | if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) { |
Will Deacon | 18b9dc1 | 2011-06-08 11:42:43 +0100 | [diff] [blame] | 720 | #ifdef CONFIG_NEON |
Tony Lindgren | 5aaf254 | 2010-07-01 13:41:05 +0100 | [diff] [blame] | 721 | if ((fmrx(MVFR1) & 0x000fff00) == 0x00011100) |
| 722 | elf_hwcap |= HWCAP_NEON; |
Catalin Marinas | 2bedbdf | 2008-11-06 13:23:07 +0000 | [diff] [blame] | 723 | #endif |
Will Deacon | 18b9dc1 | 2011-06-08 11:42:43 +0100 | [diff] [blame] | 724 | if ((fmrx(MVFR1) & 0xf0000000) == 0x10000000) |
| 725 | elf_hwcap |= HWCAP_VFPv4; |
| 726 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | } |
| 728 | return 0; |
| 729 | } |
| 730 | |
| 731 | late_initcall(vfp_init); |