diff options
Diffstat (limited to 'arch/xtensa/kernel/process.c')
| -rw-r--r-- | arch/xtensa/kernel/process.c | 306 |
1 files changed, 99 insertions, 207 deletions
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c index f53d7bd..9185597 100644 --- a/arch/xtensa/kernel/process.c +++ b/arch/xtensa/kernel/process.c @@ -52,6 +52,55 @@ void (*pm_power_off)(void) = NULL; EXPORT_SYMBOL(pm_power_off); +#if XTENSA_HAVE_COPROCESSORS + +void coprocessor_release_all(struct thread_info *ti) +{ + unsigned long cpenable; + int i; + + /* Make sure we don't switch tasks during this operation. */ + + preempt_disable(); + + /* Walk through all cp owners and release it for the requested one. */ + + cpenable = ti->cpenable; + + for (i = 0; i < XCHAL_CP_MAX; i++) { + if (coprocessor_owner[i] == ti) { + coprocessor_owner[i] = 0; + cpenable &= ~(1 << i); + } + } + + ti->cpenable = cpenable; + coprocessor_clear_cpenable(); + + preempt_enable(); +} + +void coprocessor_flush_all(struct thread_info *ti) +{ + unsigned long cpenable; + int i; + + preempt_disable(); + + cpenable = ti->cpenable; + + for (i = 0; i < XCHAL_CP_MAX; i++) { + if ((cpenable & 1) != 0 && coprocessor_owner[i] == ti) + coprocessor_flush(ti, i); + cpenable >>= 1; + } + + preempt_enable(); +} + +#endif + + /* * Powermanagement idle function, if any is provided by the platform. */ @@ -71,15 +120,36 @@ void cpu_idle(void) } /* - * Free current thread data structures etc.. + * This is called when the thread calls exit(). */ - void exit_thread(void) { +#if XTENSA_HAVE_COPROCESSORS + coprocessor_release_all(current_thread_info()); +#endif } +/* + * Flush thread state. This is called when a thread does an execve() + * Note that we flush coprocessor registers for the case execve fails. + */ void flush_thread(void) { +#if XTENSA_HAVE_COPROCESSORS + struct thread_info *ti = current_thread_info(); + coprocessor_flush_all(ti); + coprocessor_release_all(ti); +#endif +} + +/* + * This is called before the thread is copied. + */ +void prepare_to_copy(struct task_struct *tsk) +{ +#if XTENSA_HAVE_COPROCESSORS + coprocessor_flush_all(task_thread_info(tsk)); +#endif } /* @@ -107,6 +177,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, struct task_struct * p, struct pt_regs * regs) { struct pt_regs *childregs; + struct thread_info *ti; unsigned long tos; int user_mode = user_mode(regs); @@ -128,13 +199,14 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, p->set_child_tid = p->clear_child_tid = NULL; p->thread.ra = MAKE_RA_FOR_CALL((unsigned long)ret_from_fork, 0x1); p->thread.sp = (unsigned long)childregs; + if (user_mode(regs)) { int len = childregs->wmask & ~0xf; childregs->areg[1] = usp; memcpy(&childregs->areg[XCHAL_NUM_AREGS - len/4], ®s->areg[XCHAL_NUM_AREGS - len/4], len); - +// FIXME: we need to set THREADPTR in thread_info... if (clone_flags & CLONE_SETTLS) childregs->areg[2] = childregs->areg[6]; @@ -142,6 +214,12 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, /* In kernel space, we start a new thread with a new stack. */ childregs->wmask = 1; } + +#if (XTENSA_HAVE_COPROCESSORS || XTENSA_HAVE_IO_PORTS) + ti = task_thread_info(p); + ti->cpenable = 0; +#endif + return 0; } @@ -179,10 +257,6 @@ unsigned long get_wchan(struct task_struct *p) } /* - * do_copy_regs() gathers information from 'struct pt_regs' and - * 'current->thread.areg[]' to fill in the xtensa_gregset_t - * structure. - * * xtensa_gregset_t and 'struct pt_regs' are vastly different formats * of processor registers. Besides different ordering, * xtensa_gregset_t contains non-live register information that @@ -191,18 +265,19 @@ unsigned long get_wchan(struct task_struct *p) * */ -void do_copy_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs, - struct task_struct *tsk) +void xtensa_elf_core_copy_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs) { - int i, n, wb_offset; + unsigned long wb, ws, wm; + int live, last; - elfregs->xchal_config_id0 = XCHAL_HW_CONFIGID0; - elfregs->xchal_config_id1 = XCHAL_HW_CONFIGID1; + wb = regs->windowbase; + ws = regs->windowstart; + wm = regs->wmask; + ws = ((ws >> wb) | (ws << (WSBITS - wb))) & ((1 << WSBITS) - 1); - __asm__ __volatile__ ("rsr %0, 176\n" : "=a" (i)); - elfregs->cpux = i; - __asm__ __volatile__ ("rsr %0, 208\n" : "=a" (i)); - elfregs->cpuy = i; + /* Don't leak any random bits. */ + + memset(elfregs, 0, sizeof (elfregs)); /* Note: PS.EXCM is not set while user task is running; its * being set in regs->ps is for exception handling convenience. @@ -210,204 +285,22 @@ void do_copy_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs, elfregs->pc = regs->pc; elfregs->ps = (regs->ps & ~(1 << PS_EXCM_BIT)); - elfregs->exccause = regs->exccause; - elfregs->excvaddr = regs->excvaddr; - elfregs->windowbase = regs->windowbase; - elfregs->windowstart = regs->windowstart; elfregs->lbeg = regs->lbeg; elfregs->lend = regs->lend; elfregs->lcount = regs->lcount; elfregs->sar = regs->sar; - elfregs->syscall = regs->syscall; - - /* Copy register file. - * The layout looks like this: - * - * | a0 ... a15 | Z ... Z | arX ... arY | - * current window unused saved frames - */ - - memset (elfregs->ar, 0, sizeof(elfregs->ar)); + elfregs->windowstart = ws; - wb_offset = regs->windowbase * 4; - n = (regs->wmask&1)? 4 : (regs->wmask&2)? 8 : (regs->wmask&4)? 12 : 16; - - for (i = 0; i < n; i++) - elfregs->ar[(wb_offset + i) % XCHAL_NUM_AREGS] = regs->areg[i]; - - n = (regs->wmask >> 4) * 4; - - for (i = XCHAL_NUM_AREGS - n; n > 0; i++, n--) - elfregs->ar[(wb_offset + i) % XCHAL_NUM_AREGS] = regs->areg[i]; + live = (wm & 2) ? 4 : (wm & 4) ? 8 : (wm & 8) ? 12 : 16; + last = XCHAL_NUM_AREGS - (wm >> 4) * 4; + memcpy(elfregs->a, regs->areg, live * 4); + memcpy(elfregs->a + last, regs->areg + last, (wm >> 4) * 16); } -void xtensa_elf_core_copy_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs) +int dump_fpu(void) { - do_copy_regs ((xtensa_gregset_t *)elfregs, regs, current); -} - - -/* The inverse of do_copy_regs(). No error or sanity checking. */ - -void do_restore_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs, - struct task_struct *tsk) -{ - int i, n, wb_offset; - - /* Note: PS.EXCM is not set while user task is running; it - * needs to be set in regs->ps is for exception handling convenience. - */ - - regs->pc = elfregs->pc; - regs->ps = (elfregs->ps | (1 << PS_EXCM_BIT)); - regs->exccause = elfregs->exccause; - regs->excvaddr = elfregs->excvaddr; - regs->windowbase = elfregs->windowbase; - regs->windowstart = elfregs->windowstart; - regs->lbeg = elfregs->lbeg; - regs->lend = elfregs->lend; - regs->lcount = elfregs->lcount; - regs->sar = elfregs->sar; - regs->syscall = elfregs->syscall; - - /* Clear everything. */ - - memset (regs->areg, 0, sizeof(regs->areg)); - - /* Copy regs from live window frame. */ - - wb_offset = regs->windowbase * 4; - n = (regs->wmask&1)? 4 : (regs->wmask&2)? 8 : (regs->wmask&4)? 12 : 16; - - for (i = 0; i < n; i++) - regs->areg[(wb_offset+i) % XCHAL_NUM_AREGS] = elfregs->ar[i]; - - n = (regs->wmask >> 4) * 4; - - for (i = XCHAL_NUM_AREGS - n; n > 0; i++, n--) - regs->areg[(wb_offset+i) % XCHAL_NUM_AREGS] = elfregs->ar[i]; -} - -/* - * do_save_fpregs() gathers information from 'struct pt_regs' and - * 'current->thread' to fill in the elf_fpregset_t structure. - * - * Core files and ptrace use elf_fpregset_t. - */ - -void do_save_fpregs (elf_fpregset_t *fpregs, struct pt_regs *regs, - struct task_struct *tsk) -{ -#if XCHAL_HAVE_CP - - extern unsigned char _xtensa_reginfo_tables[]; - extern unsigned _xtensa_reginfo_table_size; - int i; - unsigned long flags; - - /* Before dumping coprocessor state from memory, - * ensure any live coprocessor contents for this - * task are first saved to memory: - */ - local_irq_save(flags); - - for (i = 0; i < XCHAL_CP_MAX; i++) { - if (tsk == coprocessor_info[i].owner) { - enable_coprocessor(i); - save_coprocessor_registers( - tsk->thread.cp_save+coprocessor_info[i].offset,i); - disable_coprocessor(i); - } - } - - local_irq_restore(flags); - - /* Now dump coprocessor & extra state: */ - memcpy((unsigned char*)fpregs, - _xtensa_reginfo_tables, _xtensa_reginfo_table_size); - memcpy((unsigned char*)fpregs + _xtensa_reginfo_table_size, - tsk->thread.cp_save, XTENSA_CP_EXTRA_SIZE); -#endif -} - -/* - * The inverse of do_save_fpregs(). - * Copies coprocessor and extra state from fpregs into regs and tsk->thread. - * Returns 0 on success, non-zero if layout doesn't match. - */ - -int do_restore_fpregs (elf_fpregset_t *fpregs, struct pt_regs *regs, - struct task_struct *tsk) -{ -#if XCHAL_HAVE_CP - - extern unsigned char _xtensa_reginfo_tables[]; - extern unsigned _xtensa_reginfo_table_size; - int i; - unsigned long flags; - - /* Make sure save area layouts match. - * FIXME: in the future we could allow restoring from - * a different layout of the same registers, by comparing - * fpregs' table with _xtensa_reginfo_tables and matching - * entries and copying registers one at a time. - * Not too sure yet whether that's very useful. - */ - - if( memcmp((unsigned char*)fpregs, - _xtensa_reginfo_tables, _xtensa_reginfo_table_size) ) { - return -1; - } - - /* Before restoring coprocessor state from memory, - * ensure any live coprocessor contents for this - * task are first invalidated. - */ - - local_irq_save(flags); - - for (i = 0; i < XCHAL_CP_MAX; i++) { - if (tsk == coprocessor_info[i].owner) { - enable_coprocessor(i); - save_coprocessor_registers( - tsk->thread.cp_save+coprocessor_info[i].offset,i); - coprocessor_info[i].owner = 0; - disable_coprocessor(i); - } - } - - local_irq_restore(flags); - - /* Now restore coprocessor & extra state: */ - - memcpy(tsk->thread.cp_save, - (unsigned char*)fpregs + _xtensa_reginfo_table_size, - XTENSA_CP_EXTRA_SIZE); -#endif return 0; } -/* - * Fill in the CP structure for a core dump for a particular task. - */ - -int -dump_task_fpu(struct pt_regs *regs, struct task_struct *task, elf_fpregset_t *r) -{ - return 0; /* no coprocessors active on this processor */ -} - -/* - * Fill in the CP structure for a core dump. - * This includes any FPU coprocessor. - * Here, we dump all coprocessors, and other ("extra") custom state. - * - * This function is called by elf_core_dump() in fs/binfmt_elf.c - * (in which case 'regs' comes from calls to do_coredump, see signals.c). - */ -int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r) -{ - return dump_task_fpu(regs, current, r); -} asmlinkage long xtensa_clone(unsigned long clone_flags, unsigned long newsp, @@ -421,8 +314,8 @@ long xtensa_clone(unsigned long clone_flags, unsigned long newsp, } /* - * * xtensa_execve() executes a new program. - * */ + * xtensa_execve() executes a new program. + */ asmlinkage long xtensa_execve(char __user *name, char __user * __user *argv, @@ -437,7 +330,6 @@ long xtensa_execve(char __user *name, char __user * __user *argv, error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; - // FIXME: release coprocessor?? error = do_execve(filename, argv, envp, regs); if (error == 0) { task_lock(current); |
