ftrace_64_pg_entry.S

  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * Split from ftrace_64.S
  4 */
  5
  6#include <linux/export.h>
  7#include <linux/magic.h>
  8#include <asm/ppc_asm.h>
  9#include <asm/asm-offsets.h>
 10#include <asm/ftrace.h>
 11#include <asm/ppc-opcode.h>
 12
 13_GLOBAL_TOC(ftrace_caller)
 14	lbz	r3, PACA_FTRACE_ENABLED(r13)
 15	cmpdi	r3, 0
 16	beqlr
 17
 18	/* Taken from output of objdump from lib64/glibc */
 19	mflr	r3
 20	ld	r11, 0(r1)
 21	stdu	r1, -112(r1)
 22	std	r3, 128(r1)
 23	ld	r4, 16(r11)
 24	subi	r3, r3, MCOUNT_INSN_SIZE
 25.globl ftrace_call
 26ftrace_call:
 27	bl	ftrace_stub
 28	nop
 29#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 30.globl ftrace_graph_call
 31ftrace_graph_call:
 32	b	ftrace_graph_stub
 33_GLOBAL(ftrace_graph_stub)
 34#endif
 35	ld	r0, 128(r1)
 36	mtlr	r0
 37	addi	r1, r1, 112
 38
 39_GLOBAL(ftrace_stub)
 40	blr
 41
 42#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 43_GLOBAL(ftrace_graph_caller)
 44	addi	r5, r1, 112
 45	/* load r4 with local address */
 46	ld	r4, 128(r1)
 47	subi	r4, r4, MCOUNT_INSN_SIZE
 48
 49	/* Grab the LR out of the caller stack frame */
 50	ld	r11, 112(r1)
 51	ld	r3, 16(r11)
 52
 53	bl	prepare_ftrace_return
 54	nop
 55
 56	/*
 57	 * prepare_ftrace_return gives us the address we divert to.
 58	 * Change the LR in the callers stack frame to this.
 59	 */
 60	ld	r11, 112(r1)
 61	std	r3, 16(r11)
 62
 63	ld	r0, 128(r1)
 64	mtlr	r0
 65	addi	r1, r1, 112
 66	blr
 67#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 68
 69.pushsection ".tramp.ftrace.text","aw",@progbits;
 70.globl ftrace_tramp_text
 71ftrace_tramp_text:
 72	.space 32
 73.popsection
 74
 75.pushsection ".tramp.ftrace.init","aw",@progbits;
 76.globl ftrace_tramp_init
 77ftrace_tramp_init:
 78	.space 32
 79.popsection
 80
 81_GLOBAL(mcount)
 82_GLOBAL(_mcount)
 83EXPORT_SYMBOL(_mcount)
 84	mflr	r12
 85	mtctr	r12
 86	mtlr	r0
 87	bctr
 88
 89#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 90_GLOBAL(return_to_handler)
 91	/* need to save return values */
 92#ifdef CONFIG_PPC64
 93	std	r4,  -32(r1)
 94	std	r3,  -24(r1)
 95	/* save TOC */
 96	std	r2,  -16(r1)
 97	std	r31, -8(r1)
 98	mr	r31, r1
 99	stdu	r1, -112(r1)
100
101	/*
102	 * We might be called from a module.
103	 * Switch to our TOC to run inside the core kernel.
104	 */
105	LOAD_PACA_TOC()
106#else
107	stwu	r1, -16(r1)
108	stw	r3, 8(r1)
109	stw	r4, 12(r1)
110#endif
111
112	bl	ftrace_return_to_handler
113	nop
114
115	/* return value has real return address */
116	mtlr	r3
117
118#ifdef CONFIG_PPC64
119	ld	r1, 0(r1)
120	ld	r4,  -32(r1)
121	ld	r3,  -24(r1)
122	ld	r2,  -16(r1)
123	ld	r31, -8(r1)
124#else
125	lwz	r3, 8(r1)
126	lwz	r4, 12(r1)
127	addi	r1, r1, 16
128#endif
129
130	/* Jump back to real return address */
131	blr
132#endif /* CONFIG_FUNCTION_GRAPH_TRACER */