Merge tag 'xtensa-20170507' of git://github.com/jcmvbkbc/linux-xtensa

Pull Xtensa updates from Max Filippov:

 - clearly mark references to spilled register locations with SPILL_SLOT
   macros

 - clean up xtensa ptrace: use generic tracehooks, move internal kernel
   definitions from uapi/asm to asm, make locally-used functions static,
   fix code style and alignment

 - use command line parameters passed to ISS as kernel command line.

* tag 'xtensa-20170507' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: clean up access to spilled registers locations
  xtensa: use generic tracehooks
  xtensa: move internal ptrace definitions from uapi/asm to asm
  xtensa: clean up xtensa/kernel/ptrace.c
  xtensa: drop unused fast_io_protect function
  xtensa: use ITLB_HIT_BIT instead of hardcoded number
  xtensa: ISS: update kernel command line in platform_setup
  xtensa: ISS: add argc/argv simcall definitions
  xtensa: ISS: cleanup setup.c

arch/xtensa/include/asm/processor.h

@@ -113,6 +113,21 @@
  */
 #define MAKE_PC_FROM_RA(ra,sp)    (((ra) & 0x3fffffff) | ((sp) & 0xc0000000))
 
+/* Spill slot location for the register reg in the spill area under the stack
+ * pointer sp. reg must be in the range [0..4).
+ */
+#define SPILL_SLOT(sp, reg) (*(((unsigned long *)(sp)) - 4 + (reg)))
+
+/* Spill slot location for the register reg in the spill area under the stack
+ * pointer sp for the call8. reg must be in the range [4..8).
+ */
+#define SPILL_SLOT_CALL8(sp, reg) (*(((unsigned long *)(sp)) - 12 + (reg)))
+
+/* Spill slot location for the register reg in the spill area under the stack
+ * pointer sp for the call12. reg must be in the range [4..12).
+ */
+#define SPILL_SLOT_CALL12(sp, reg) (*(((unsigned long *)(sp)) - 16 + (reg)))
+
 typedef struct {
 	unsigned long seg;
 } mm_segment_t;

arch/xtensa/include/asm/ptrace.h

@@ -12,6 +12,45 @@
 
 #include <uapi/asm/ptrace.h>
 
+/*
+ * Kernel stack
+ *
+ *		+-----------------------+  -------- STACK_SIZE
+ *		|     register file     |  |
+ *		+-----------------------+  |
+ *		|    struct pt_regs     |  |
+ *		+-----------------------+  | ------ PT_REGS_OFFSET
+ * double	:  16 bytes spill area  :  |  ^
+ * excetion	:- - - - - - - - - - - -:  |  |
+ * frame	:    struct pt_regs     :  |  |
+ *		:- - - - - - - - - - - -:  |  |
+ *		|                       |  |  |
+ *		|     memory stack      |  |  |
+ *		|                       |  |  |
+ *		~                       ~  ~  ~
+ *		~                       ~  ~  ~
+ *		|                       |  |  |
+ *		|                       |  |  |
+ *		+-----------------------+  |  | --- STACK_BIAS
+ *		|  struct task_struct   |  |  |  ^
+ *  current --> +-----------------------+  |  |  |
+ *		|  struct thread_info   |  |  |  |
+ *		+-----------------------+ --------
+ */
+
+#define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
+
+/*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */
+
+#define EXC_TABLE_KSTK		0x004	/* Kernel Stack */
+#define EXC_TABLE_DOUBLE_SAVE	0x008	/* Double exception save area for a0 */
+#define EXC_TABLE_FIXUP		0x00c	/* Fixup handler */
+#define EXC_TABLE_PARAM		0x010	/* For passing a parameter to fixup */
+#define EXC_TABLE_SYSCALL_SAVE	0x014	/* For fast syscall handler */
+#define EXC_TABLE_FAST_USER	0x100	/* Fast user exception handler */
+#define EXC_TABLE_FAST_KERNEL	0x200	/* Fast kernel exception handler */
+#define EXC_TABLE_DEFAULT	0x300	/* Default C-Handler */
+#define EXC_TABLE_SIZE		0x400
 
 #ifndef __ASSEMBLY__
 

arch/xtensa/include/uapi/asm/ptrace.h

@@ -11,46 +11,6 @@
 #ifndef _UAPI_XTENSA_PTRACE_H
 #define _UAPI_XTENSA_PTRACE_H
 
-/*
- * Kernel stack
- *
- * 		+-----------------------+  -------- STACK_SIZE
- * 		|     register file     |  |
- * 		+-----------------------+  |
- * 		|    struct pt_regs     |  |
- * 		+-----------------------+  | ------ PT_REGS_OFFSET
- * double 	:  16 bytes spill area  :  |  ^
- * excetion 	:- - - - - - - - - - - -:  |  |
- * frame	:    struct pt_regs     :  |  |
- * 		:- - - - - - - - - - - -:  |  |
- * 		|                       |  |  |
- * 		|     memory stack      |  |  |
- * 		|                       |  |  |
- * 		~                       ~  ~  ~
- * 		~                       ~  ~  ~
- * 		|                       |  |  |
- * 		|                       |  |  |
- * 		+-----------------------+  |  | --- STACK_BIAS
- * 		|  struct task_struct   |  |  |  ^
- *  current --> +-----------------------+  |  |  |
- * 		|  struct thread_info   |  |  |  |
- *		+-----------------------+ --------
- */
-
-#define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
-
-/*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */
-
-#define EXC_TABLE_KSTK		0x004	/* Kernel Stack */
-#define EXC_TABLE_DOUBLE_SAVE	0x008	/* Double exception save area for a0 */
-#define EXC_TABLE_FIXUP		0x00c	/* Fixup handler */
-#define EXC_TABLE_PARAM		0x010	/* For passing a parameter to fixup */
-#define EXC_TABLE_SYSCALL_SAVE	0x014	/* For fast syscall handler */
-#define EXC_TABLE_FAST_USER	0x100	/* Fast user exception handler */
-#define EXC_TABLE_FAST_KERNEL	0x200	/* Fast kernel exception handler */
-#define EXC_TABLE_DEFAULT	0x300	/* Default C-Handler */
-#define EXC_TABLE_SIZE		0x400
-
 /* Registers used by strace */
 
 #define REG_A_BASE	0x0000

arch/xtensa/kernel/coprocessor.S

@@ -26,30 +26,6 @@
 #include <asm/signal.h>
 #include <asm/tlbflush.h>
 
-/*
- * Entry condition:
- *
- *   a0:	trashed, original value saved on stack (PT_AREG0)
- *   a1:	a1
- *   a2:	new stack pointer, original in DEPC
- *   a3:	a3
- *   depc:	a2, original value saved on stack (PT_DEPC)
- *   excsave_1:	dispatch table
- *
- *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
- *	     <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
- */
-
-/* IO protection is currently unsupported. */
-
-ENTRY(fast_io_protect)
-
-	wsr	a0, excsave1
-	movi	a0, unrecoverable_exception
-	callx0	a0
-
-ENDPROC(fast_io_protect)
-
 #if XTENSA_HAVE_COPROCESSORS
 
 /*

arch/xtensa/kernel/entry.S

@@ -1899,10 +1899,11 @@ ENTRY(system_call)
 	movi	a4, do_syscall_trace_enter
 	s32i	a3, a2, PT_SYSCALL
 	callx4	a4
+	mov	a3, a6
 
 	/* syscall = sys_call_table[syscall_nr] */
 
-	movi	a4, sys_call_table;
+	movi	a4, sys_call_table
 	movi	a5, __NR_syscall_count
 	movi	a6, -ENOSYS
 	bgeu	a3, a5, 1f

arch/xtensa/kernel/process.c

@@ -204,8 +204,8 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
 #endif
 
 	/* Create a call4 dummy-frame: a0 = 0, a1 = childregs. */
-	*((int*)childregs - 3) = (unsigned long)childregs;
-	*((int*)childregs - 4) = 0;
+	SPILL_SLOT(childregs, 1) = (unsigned long)childregs;
+	SPILL_SLOT(childregs, 0) = 0;
 
 	p->thread.sp = (unsigned long)childregs;
 
@@ -266,8 +266,8 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
 		/* pass parameters to ret_from_kernel_thread:
 		 * a2 = thread_fn, a3 = thread_fn arg
 		 */
-		*((int *)childregs - 1) = thread_fn_arg;
-		*((int *)childregs - 2) = usp_thread_fn;
+		SPILL_SLOT(childregs, 3) = thread_fn_arg;
+		SPILL_SLOT(childregs, 2) = usp_thread_fn;
 
 		/* Childregs are only used when we're going to userspace
 		 * in which case start_thread will set them up.