summaryrefslogtreecommitdiffstats
path: root/arch/xtensa/kernel/process.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/xtensa/kernel/process.c')
-rw-r--r--arch/xtensa/kernel/process.c261
1 files changed, 102 insertions, 159 deletions
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index 026138d..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],
&regs->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
@@ -191,9 +265,20 @@ 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)
{
+ unsigned long wb, ws, wm;
+ int live, last;
+
+ wb = regs->windowbase;
+ ws = regs->windowstart;
+ wm = regs->wmask;
+ ws = ((ws >> wb) | (ws << (WSBITS - wb))) & ((1 << WSBITS) - 1);
+
+ /* 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.
*/
@@ -204,159 +289,18 @@ void do_copy_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs,
elfregs->lend = regs->lend;
elfregs->lcount = regs->lcount;
elfregs->sar = regs->sar;
+ elfregs->windowstart = ws;
- memcpy (elfregs->a, regs->areg, sizeof(elfregs->a));
-}
-
-void xtensa_elf_core_copy_regs (xtensa_gregset_t *elfregs, struct pt_regs *regs)
-{
- 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)
-{
- const unsigned long ps_mask = PS_CALLINC_MASK | PS_OWB_MASK;
- unsigned long ps;
-
- /* Note: PS.EXCM is not set while user task is running; it
- * needs to be set in regs->ps is for exception handling convenience.
- */
-
- ps = (regs->ps & ~ps_mask) | (elfregs->ps & ps_mask) | (1<<PS_EXCM_BIT);
- regs->ps = ps;
- regs->pc = elfregs->pc;
- regs->lbeg = elfregs->lbeg;
- regs->lend = elfregs->lend;
- regs->lcount = elfregs->lcount;
- regs->sar = elfregs->sar;
-
- memcpy (regs->areg, elfregs->a, sizeof(regs->areg));
-}
-
-/*
- * 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
+ 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);
}
-/*
- * 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)
+int dump_fpu(void)
{
-#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,
@@ -370,8 +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,
@@ -386,7 +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);
OpenPOWER on IntegriCloud