1/*
  2 * Copyright 2012 Tilera Corporation. All Rights Reserved.
  3 *
  4 *   This program is free software; you can redistribute it and/or
  5 *   modify it under the terms of the GNU General Public License
  6 *   as published by the Free Software Foundation, version 2.
  7 *
  8 *   This program is distributed in the hope that it will be useful, but
  9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 11 *   NON INFRINGEMENT.  See the GNU General Public License for
 12 *   more details.
 13 *
 14 * TILE-Gx specific __mcount support
 15 */
 16
 17#include <linux/linkage.h>
 18#include <asm/ftrace.h>
 19
 20#define REGSIZE 8
 21
 22	.text
 23	.global __mcount
 24
 25	.macro	MCOUNT_SAVE_REGS
 26	addli	sp, sp, -REGSIZE
 27	{
 28	 st     sp, lr
 29	 addli	r29, sp, - (12 * REGSIZE)
 30	}
 31	{
 32	 addli	sp, sp, - (13 * REGSIZE)
 33	 st     r29, sp
 34	}
 35	addli	r29, r29, REGSIZE
 36	{ st	r29, r0; addli	r29, r29, REGSIZE }
 37	{ st	r29, r1; addli	r29, r29, REGSIZE }
 38	{ st	r29, r2; addli	r29, r29, REGSIZE }
 39	{ st	r29, r3; addli	r29, r29, REGSIZE }
 40	{ st	r29, r4; addli	r29, r29, REGSIZE }
 41	{ st	r29, r5; addli	r29, r29, REGSIZE }
 42	{ st	r29, r6; addli	r29, r29, REGSIZE }
 43	{ st	r29, r7; addli	r29, r29, REGSIZE }
 44	{ st	r29, r8; addli	r29, r29, REGSIZE }
 45	{ st	r29, r9; addli	r29, r29, REGSIZE }
 46	{ st	r29, r10; addli	r29, r29, REGSIZE }
 47	.endm
 48
 49	.macro	MCOUNT_RESTORE_REGS
 50	addli	r29, sp, (2 * REGSIZE)
 51	{ ld	r0, r29; addli	r29, r29, REGSIZE }
 52	{ ld	r1, r29; addli	r29, r29, REGSIZE }
 53	{ ld	r2, r29; addli	r29, r29, REGSIZE }
 54	{ ld	r3, r29; addli	r29, r29, REGSIZE }
 55	{ ld	r4, r29; addli	r29, r29, REGSIZE }
 56	{ ld	r5, r29; addli	r29, r29, REGSIZE }
 57	{ ld	r6, r29; addli	r29, r29, REGSIZE }
 58	{ ld	r7, r29; addli	r29, r29, REGSIZE }
 59	{ ld	r8, r29; addli	r29, r29, REGSIZE }
 60	{ ld	r9, r29; addli	r29, r29, REGSIZE }
 61	{ ld	r10, r29; addli	lr, sp, (13 * REGSIZE) }
 62	{ ld	lr, lr;  addli	sp, sp, (14 * REGSIZE) }
 63	.endm
 64
 65	.macro  RETURN_BACK
 66	{ move	r12, lr; move	lr, r10 }
 67	jrp	r12
 68	.endm
 69
 70#ifdef CONFIG_DYNAMIC_FTRACE
 71
 72	.align	64
 73STD_ENTRY(__mcount)
 74__mcount:
 75	j	ftrace_stub
 76STD_ENDPROC(__mcount)
 77
 78	.align	64
 79STD_ENTRY(ftrace_caller)
 80	MCOUNT_SAVE_REGS
 81
 82	/* arg1: self return address */
 83	/* arg2: parent's return address */
 84	/* arg3: ftrace_ops */
 85	/* arg4: regs (but make it NULL) */
 86	{ move	r0, lr;  moveli        r2, hw2_last(function_trace_op) }
 87	{ move	r1, r10; shl16insli    r2, r2, hw1(function_trace_op) }
 88	{ movei	r3, 0;   shl16insli    r2, r2, hw0(function_trace_op) }
 89	ld	r2,r2
 90
 91	.global	ftrace_call
 92ftrace_call:
 93	/*
 94	 * a placeholder for the call to a real tracing function, i.e.
 95	 * ftrace_trace_function()
 96	 */
 97	nop
 98
 99#ifdef CONFIG_FUNCTION_GRAPH_TRACER
100	.global	ftrace_graph_call
101ftrace_graph_call:
102	/*
103	 * a placeholder for the call to a real tracing function, i.e.
104	 * ftrace_graph_caller()
105	 */
106	nop
107#endif
108	MCOUNT_RESTORE_REGS
109	.global	ftrace_stub
110ftrace_stub:
111	RETURN_BACK
112STD_ENDPROC(ftrace_caller)
113
114#else /* ! CONFIG_DYNAMIC_FTRACE */
115
116	.align	64
117STD_ENTRY(__mcount)
118	{
119	 moveli	r11, hw2_last(ftrace_trace_function)
120	 moveli	r13, hw2_last(ftrace_stub)
121	}
122	{
123	 shl16insli	r11, r11, hw1(ftrace_trace_function)
124	 shl16insli	r13, r13, hw1(ftrace_stub)
125	}
126	{
127	 shl16insli	r11, r11, hw0(ftrace_trace_function)
128	 shl16insli	r13, r13, hw0(ftrace_stub)
129	}
130
131	ld	r11, r11
132	sub	r14, r13, r11
133	bnez	r14, static_trace
134
135#ifdef	CONFIG_FUNCTION_GRAPH_TRACER
136	moveli	r15, hw2_last(ftrace_graph_return)
137	shl16insli	r15, r15, hw1(ftrace_graph_return)
138	shl16insli	r15, r15, hw0(ftrace_graph_return)
139	ld	r15, r15
140	sub	r15, r15, r13
141	bnez	r15, ftrace_graph_caller
142
143	{
144	 moveli	r16, hw2_last(ftrace_graph_entry)
145	 moveli	r17, hw2_last(ftrace_graph_entry_stub)
146	}
147	{
148	 shl16insli	r16, r16, hw1(ftrace_graph_entry)
149	 shl16insli	r17, r17, hw1(ftrace_graph_entry_stub)
150	}
151	{
152	 shl16insli	r16, r16, hw0(ftrace_graph_entry)
153	 shl16insli	r17, r17, hw0(ftrace_graph_entry_stub)
154	}
155	ld	r16, r16
156	sub	r17, r16, r17
157	bnez	r17, ftrace_graph_caller
158
159#endif
160	RETURN_BACK
161
162static_trace:
163	MCOUNT_SAVE_REGS
164
165	/* arg1: self return address */
166	/* arg2: parent's return address */
167	{ move	r0, lr; move	r1, r10 }
168
169	/* call ftrace_trace_function() */
170	jalr	r11
171
172	MCOUNT_RESTORE_REGS
173
174	.global ftrace_stub
175ftrace_stub:
176	RETURN_BACK
177STD_ENDPROC(__mcount)
178
179#endif	/* ! CONFIG_DYNAMIC_FTRACE */
180
181#ifdef CONFIG_FUNCTION_GRAPH_TRACER
182
183STD_ENTRY(ftrace_graph_caller)
184ftrace_graph_caller:
185#ifndef CONFIG_DYNAMIC_FTRACE
186	MCOUNT_SAVE_REGS
187#endif
188
189	/* arg1: Get the location of the parent's return address */
190	addi	r0, sp, 12 * REGSIZE
191	/* arg2: Get self return address */
192	move	r1, lr
193
194	jal prepare_ftrace_return
195
196	MCOUNT_RESTORE_REGS
197	RETURN_BACK
198STD_ENDPROC(ftrace_graph_caller)
199
200	.global return_to_handler
201return_to_handler:
202	MCOUNT_SAVE_REGS
203
204	jal	ftrace_return_to_handler
205	/* restore the real parent address */
206	move	r11, r0
207
208	MCOUNT_RESTORE_REGS
209	jr	r11
210
211#endif /* CONFIG_FUNCTION_GRAPH_TRACER */