--- zzzz-none-000/linux-3.10.107/arch/arm/kernel/iwmmxt.S	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arm/kernel/iwmmxt.S	2021-02-04 17:41:59.000000000 +0000
@@ -18,13 +18,18 @@
 #include <asm/ptrace.h>
 #include <asm/thread_info.h>
 #include <asm/asm-offsets.h>
+#include <asm/assembler.h>
 
-#if defined(CONFIG_CPU_PJ4)
+#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B)
 #define PJ4(code...)		code
 #define XSC(code...)
-#else
+#elif defined(CONFIG_CPU_MOHAWK) || \
+	defined(CONFIG_CPU_XSC3) || \
+	defined(CONFIG_CPU_XSCALE)
 #define PJ4(code...)
 #define XSC(code...)		code
+#else
+#error "Unsupported iWMMXt architecture"
 #endif
 
 #define MMX_WR0		 	(0x00)
@@ -53,6 +58,7 @@
 #define MMX_SIZE		(0x98)
 
 	.text
+	.arm
 
 /*
  * Lazy switching of Concan coprocessor context
@@ -61,17 +67,18 @@
  * r9  = ret_from_exception
  * lr  = undefined instr exit
  *
- * called from prefetch exception handler with interrupts disabled
+ * called from prefetch exception handler with interrupts enabled
  */
 
 ENTRY(iwmmxt_task_enable)
+	inc_preempt_count r10, r3
 
 	XSC(mrc	p15, 0, r2, c15, c1, 0)
 	PJ4(mrc p15, 0, r2, c1, c0, 2)
 	@ CP0 and CP1 accessible?
 	XSC(tst	r2, #0x3)
 	PJ4(tst	r2, #0xf)
-	movne	pc, lr				@ if so no business here
+	bne	4f				@ if so no business here
 	@ enable access to CP0 and CP1
 	XSC(orr	r2, r2, #0x3)
 	XSC(mcr	p15, 0, r2, c15, c1, 0)
@@ -88,13 +95,19 @@
 
 	mrc	p15, 0, r2, c2, c0, 0
 	mov	r2, r2				@ cpwait
+	bl	concan_save
 
-	teq	r1, #0				@ test for last ownership
-	mov	lr, r9				@ normal exit from exception
-	beq	concan_load			@ no owner, skip save
+#ifdef CONFIG_PREEMPT_COUNT
+	get_thread_info r10
+#endif
+4:	dec_preempt_count r10, r3
+	ret	r9				@ normal exit from exception
 
 concan_save:
 
+	teq	r1, #0				@ test for last ownership
+	beq	concan_load			@ no owner, skip save
+
 	tmrc	r2, wCon
 
 	@ CUP? wCx
@@ -132,7 +145,7 @@
 	wstrd	wR15, [r1, #MMX_WR15]
 
 2:	teq	r0, #0				@ anything to load?
-	moveq	pc, lr
+	reteq	lr				@ if not, return
 
 concan_load:
 
@@ -165,9 +178,12 @@
 	@ clear CUP/MUP (only if r1 != 0)
 	teq	r1, #0
 	mov 	r2, #0
-	moveq	pc, lr
+	reteq	lr
+
 	tmcr	wCon, r2
-	mov	pc, lr
+	ret	lr
+
+ENDPROC(iwmmxt_task_enable)
 
 /*
  * Back up Concan regs to save area and disable access to them
@@ -219,6 +235,8 @@
 1:	msr	cpsr_c, ip			@ restore interrupt mode
 	ldmfd	sp!, {r4, pc}
 
+ENDPROC(iwmmxt_task_disable)
+
 /*
  * Copy Concan state to given memory address
  *
@@ -253,7 +271,9 @@
 	mov	r3, lr				@ preserve return address
 	bl	concan_dump
 	msr	cpsr_c, ip			@ restore interrupt mode
-	mov	pc, r3
+	ret	r3
+
+ENDPROC(iwmmxt_task_copy)
 
 /*
  * Restore Concan state from given memory address
@@ -289,7 +309,9 @@
 	mov	r3, lr				@ preserve return address
 	bl	concan_load
 	msr	cpsr_c, ip			@ restore interrupt mode
-	mov	pc, r3
+	ret	r3
+
+ENDPROC(iwmmxt_task_restore)
 
 /*
  * Concan handling on task switch
@@ -311,7 +333,7 @@
 	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
+	retne	lr				@ no: leave Concan disabled
 
 1:	@ flip Concan access
 	XSC(eor	r1, r1, #0x3)
@@ -322,6 +344,8 @@
 	mrc	p15, 0, r1, c2, c0, 0
 	sub	pc, lr, r1, lsr #32		@ cpwait and return
 
+ENDPROC(iwmmxt_task_switch)
+
 /*
  * Remove Concan ownership of given task
  *
@@ -338,7 +362,9 @@
 	eors	r0, r0, r1			@ if equal...
 	streq	r0, [r3]			@ then clear ownership
 	msr	cpsr_c, r2			@ restore interrupts
-	mov	pc, lr
+	ret	lr
+
+ENDPROC(iwmmxt_task_release)
 
 	.data
 concan_owner: