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-rw-r--r--arch/arm/kernel/Makefile2
-rw-r--r--arch/arm/kernel/entry-armv.S4
-rw-r--r--arch/arm/kernel/iwmmxt-notifier.c64
-rw-r--r--arch/arm/kernel/iwmmxt.S27
-rw-r--r--arch/arm/kernel/process.c6
-rw-r--r--include/asm-arm/thread_info.h1
6 files changed, 79 insertions, 25 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 7cffbaef064..f0c0cdb1c18 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -25,7 +25,7 @@ obj-$(CONFIG_OABI_COMPAT) += sys_oabi-compat.o
obj-$(CONFIG_CRUNCH) += crunch.o crunch-bits.o
AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312
-obj-$(CONFIG_IWMMXT) += iwmmxt.o
+obj-$(CONFIG_IWMMXT) += iwmmxt.o iwmmxt-notifier.o
AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt
ifneq ($(CONFIG_ARCH_EBSA110),y)
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 6423a38839b..0e8aeaf9ff1 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -590,9 +590,7 @@ ENTRY(__switch_to)
#ifdef CONFIG_MMU
mcr p15, 0, r6, c3, c0, 0 @ Set domain register
#endif
-#if defined(CONFIG_IWMMXT)
- bl iwmmxt_task_switch
-#elif defined(CONFIG_CPU_XSCALE)
+#if defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_IWMMXT)
add r4, r2, #TI_CPU_DOMAIN + 40 @ cpu_context_save->extra
ldmib r4, {r4, r5}
mar acc0, r4, r5
diff --git a/arch/arm/kernel/iwmmxt-notifier.c b/arch/arm/kernel/iwmmxt-notifier.c
new file mode 100644
index 00000000000..44a86c33796
--- /dev/null
+++ b/arch/arm/kernel/iwmmxt-notifier.c
@@ -0,0 +1,64 @@
+/*
+ * linux/arch/arm/kernel/iwmmxt-notifier.c
+ *
+ * XScale iWMMXt (Concan) context switching and handling
+ *
+ * Initial code:
+ * Copyright (c) 2003, Intel Corporation
+ *
+ * Full lazy switching support, optimizations and more, by Nicolas Pitre
+ * Copyright (c) 2003-2004, MontaVista Software, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <asm/thread_notify.h>
+#include <asm/io.h>
+
+static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t)
+{
+ struct thread_info *thread = t;
+
+ switch (cmd) {
+ case THREAD_NOTIFY_FLUSH:
+ /*
+ * flush_thread() zeroes thread->fpstate, so no need
+ * to do anything here.
+ *
+ * FALLTHROUGH: Ensure we don't try to overwrite our newly
+ * initialised state information on the first fault.
+ */
+
+ case THREAD_NOTIFY_RELEASE:
+ iwmmxt_task_release(thread);
+ break;
+
+ case THREAD_NOTIFY_SWITCH:
+ iwmmxt_task_switch(thread);
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block iwmmxt_notifier_block = {
+ .notifier_call = iwmmxt_do,
+};
+
+static int __init iwmmxt_init(void)
+{
+ thread_register_notifier(&iwmmxt_notifier_block);
+
+ return 0;
+}
+
+late_initcall(iwmmxt_init);
diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S
index a3bae95e536..b63b528f22a 100644
--- a/arch/arm/kernel/iwmmxt.S
+++ b/arch/arm/kernel/iwmmxt.S
@@ -271,30 +271,27 @@ ENTRY(iwmmxt_task_restore)
/*
* Concan handling on task switch
*
- * r0 = previous task_struct pointer (must be preserved)
- * r1 = previous thread_info pointer
- * r2 = next thread_info pointer (must be preserved)
+ * r0 = next thread_info pointer
*
- * Called only from __switch_to with task preemption disabled.
- * No need to care about preserving r4 and above.
+ * Called only from the iwmmxt notifier with task preemption disabled.
*/
ENTRY(iwmmxt_task_switch)
- mrc p15, 0, r4, c15, c1, 0
- tst r4, #0x3 @ CP0 and CP1 accessible?
+ mrc p15, 0, r1, c15, c1, 0
+ tst r1, #0x3 @ CP0 and CP1 accessible?
bne 1f @ yes: block them for next task
- ldr r5, =concan_owner
- add r6, r2, #TI_IWMMXT_STATE @ get next task Concan save area
- ldr r5, [r5] @ get current Concan owner
- teq r5, r6 @ next task owns it?
+ ldr r2, =concan_owner
+ add r3, r0, #TI_IWMMXT_STATE @ get next task Concan save area
+ ldr r2, [r2] @ get current Concan owner
+ teq r2, r3 @ next task owns it?
movne pc, lr @ no: leave Concan disabled
-1: eor r4, r4, #3 @ flip Concan access
- mcr p15, 0, r4, c15, c1, 0
+1: eor r1, r1, #3 @ flip Concan access
+ mcr p15, 0, r1, c15, c1, 0
- mrc p15, 0, r4, c2, c0, 0
- sub pc, lr, r4, lsr #32 @ cpwait and return
+ mrc p15, 0, r1, c2, c0, 0
+ sub pc, lr, r1, lsr #32 @ cpwait and return
/*
* Remove Concan ownership of given task
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index e1c77ee885a..b5773a2549e 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -353,9 +353,6 @@ void flush_thread(void)
memset(&thread->fpstate, 0, sizeof(union fp_state));
thread_notify(THREAD_NOTIFY_FLUSH, thread);
-#if defined(CONFIG_IWMMXT)
- iwmmxt_task_release(thread);
-#endif
}
void release_thread(struct task_struct *dead_task)
@@ -363,9 +360,6 @@ void release_thread(struct task_struct *dead_task)
struct thread_info *thread = task_thread_info(dead_task);
thread_notify(THREAD_NOTIFY_RELEASE, thread);
-#if defined(CONFIG_IWMMXT)
- iwmmxt_task_release(thread);
-#endif
}
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
diff --git a/include/asm-arm/thread_info.h b/include/asm-arm/thread_info.h
index c46b5c84275..c52e0bf7535 100644
--- a/include/asm-arm/thread_info.h
+++ b/include/asm-arm/thread_info.h
@@ -111,6 +111,7 @@ extern void iwmmxt_task_disable(struct thread_info *);
extern void iwmmxt_task_copy(struct thread_info *, void *);
extern void iwmmxt_task_restore(struct thread_info *, void *);
extern void iwmmxt_task_release(struct thread_info *);
+extern void iwmmxt_task_switch(struct thread_info *);
#endif