diff options
Diffstat (limited to 'arch/arm/vfp/vfpmodule.c')
-rw-r--r-- | arch/arm/vfp/vfpmodule.c | 77 |
1 files changed, 43 insertions, 34 deletions
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index f60a540..315a540 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -197,10 +197,13 @@ static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_ } /* - * Update the FPSCR with the additional exception flags. + * If any of the status flags are set, update the FPSCR. * Comparison instructions always return at least one of * these flags set. */ + if (exceptions & (FPSCR_N|FPSCR_Z|FPSCR_C|FPSCR_V)) + fpscr &= ~(FPSCR_N|FPSCR_Z|FPSCR_C|FPSCR_V); + fpscr |= exceptions; fmxr(FPSCR, fpscr); @@ -425,54 +428,60 @@ static void vfp_pm_init(void) static inline void vfp_pm_init(void) { } #endif /* CONFIG_PM */ -/* - * Synchronise the hardware VFP state of a thread other than current with the - * saved one. This function is used by the ptrace mechanism. - */ -#ifdef CONFIG_SMP -void vfp_sync_state(struct thread_info *thread) +void vfp_sync_hwstate(struct thread_info *thread) { + unsigned int cpu = get_cpu(); + /* - * On SMP systems, the VFP state is automatically saved at every - * context switch. We mark the thread VFP state as belonging to a - * non-existent CPU so that the saved one will be reloaded when - * needed. + * If the thread we're interested in is the current owner of the + * hardware VFP state, then we need to save its state. */ - thread->vfpstate.hard.cpu = NR_CPUS; + if (last_VFP_context[cpu] == &thread->vfpstate) { + u32 fpexc = fmrx(FPEXC); + + /* + * Save the last VFP state on this CPU. + */ + fmxr(FPEXC, fpexc | FPEXC_EN); + vfp_save_state(&thread->vfpstate, fpexc | FPEXC_EN); + fmxr(FPEXC, fpexc); + } + + put_cpu(); } -#else -void vfp_sync_state(struct thread_info *thread) + +void vfp_flush_hwstate(struct thread_info *thread) { unsigned int cpu = get_cpu(); - u32 fpexc = fmrx(FPEXC); /* - * If VFP is enabled, the previous state was already saved and - * last_VFP_context updated. + * If the thread we're interested in is the current owner of the + * hardware VFP state, then we need to save its state. */ - if (fpexc & FPEXC_EN) - goto out; + if (last_VFP_context[cpu] == &thread->vfpstate) { + u32 fpexc = fmrx(FPEXC); - if (!last_VFP_context[cpu]) - goto out; + fmxr(FPEXC, fpexc & ~FPEXC_EN); - /* - * Save the last VFP state on this CPU. - */ - fmxr(FPEXC, fpexc | FPEXC_EN); - vfp_save_state(last_VFP_context[cpu], fpexc); - fmxr(FPEXC, fpexc); + /* + * Set the context to NULL to force a reload the next time + * the thread uses the VFP. + */ + last_VFP_context[cpu] = NULL; + } +#ifdef CONFIG_SMP /* - * Set the context to NULL to force a reload the next time the thread - * uses the VFP. + * For SMP we still have to take care of the case where the thread + * migrates to another CPU and then back to the original CPU on which + * the last VFP user is still the same thread. Mark the thread VFP + * state as belonging to a non-existent CPU so that the saved one will + * be reloaded in the above case. */ - last_VFP_context[cpu] = NULL; - -out: + thread->vfpstate.hard.cpu = NR_CPUS; +#endif put_cpu(); } -#endif #include <linux/smp.h> @@ -525,7 +534,7 @@ static int __init vfp_init(void) */ elf_hwcap |= HWCAP_VFP; #ifdef CONFIG_VFPv3 - if (VFP_arch >= 3) { + if (VFP_arch >= 2) { elf_hwcap |= HWCAP_VFPv3; /* |