@ from the exception stack
#if __LINUX_ARM_ARCH__ < 6 && !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG)
+#ifndef CONFIG_MMU
+#warning "NPTL on non MMU needs fixing"
+#else
@ make sure our user space atomic helper is aborted
cmp r2, #TASK_SIZE
bichs r3, r3, #PSR_Z_BIT
+#endif
#endif
@
movcss r7, r5, lsr #(TIF_USING_IWMMXT + 1)
bcs iwmmxt_task_enable
#endif
- enable_irq
add pc, pc, r8, lsr #6
mov r0, r0
mov pc, lr @ CP#15 (Control)
do_fpe:
+ enable_irq
ldr r4, .LCfp
add r10, r10, #TI_FPSTATE @ r10 = workspace
ldr pc, [r4] @ Call FP module USR entry point
ldr r6, [r2, #TI_CPU_DOMAIN]!
#endif
#if __LINUX_ARM_ARCH__ >= 6
-#ifdef CONFIG_CPU_MPCORE
+#ifdef CONFIG_CPU_32v6K
clrex
#else
strex r5, r4, [ip] @ Clear exclusive monitor
* The C flag is also set if *ptr was changed to allow for assembly
* optimization in the calling code.
*
- * Note: this routine already includes memory barriers as needed.
+ * Notes:
+ *
+ * - This routine already includes memory barriers as needed.
+ *
+ * - A failure might be transient, i.e. it is possible, although unlikely,
+ * that "failure" be returned even if *ptr == oldval.
*
* For example, a user space atomic_add implementation could look like this:
*
* The kernel itself must perform the operation.
* A special ghost syscall is used for that (see traps.c).
*/
+ stmfd sp!, {r7, lr}
+ mov r7, #0xff00 @ 0xfff0 into r7 for EABI
+ orr r7, r7, #0xf0
swi #0x9ffff0
- mov pc, lr
+ ldmfd sp!, {r7, pc}
#elif __LINUX_ARM_ARCH__ < 6
* exception happening just after the str instruction which would
* clear the Z flag although the exchange was done.
*/
+#ifdef CONFIG_MMU
teq ip, ip @ set Z flag
ldr ip, [r2] @ load current val
add r3, r2, #1 @ prepare store ptr
teqeq ip, r0 @ compare with oldval if still allowed
streq r1, [r3, #-1]! @ store newval if still allowed
subs r0, r2, r3 @ if r2 == r3 the str occured
+#else
+#warning "NPTL on non MMU needs fixing"
+ mov r0, #-1
+ adds r0, r0, #0
+#endif
mov pc, lr
#else