xref: /aosp_15_r20/external/arm-trusted-firmware/include/common/asm_macros_common.S (revision 54fd6939e177f8ff529b10183254802c76df6d08)
1*54fd6939SJiyong Park/*
2*54fd6939SJiyong Park * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
3*54fd6939SJiyong Park *
4*54fd6939SJiyong Park * SPDX-License-Identifier: BSD-3-Clause
5*54fd6939SJiyong Park */
6*54fd6939SJiyong Park#ifndef ASM_MACROS_COMMON_S
7*54fd6939SJiyong Park#define ASM_MACROS_COMMON_S
8*54fd6939SJiyong Park
9*54fd6939SJiyong Park	/*
10*54fd6939SJiyong Park	 * This macro is used to create a function label and place the
11*54fd6939SJiyong Park	 * code into a separate text section based on the function name
12*54fd6939SJiyong Park	 * to enable elimination of unused code during linking. It also adds
13*54fd6939SJiyong Park	 * basic debug information to enable call stack printing most of the
14*54fd6939SJiyong Park	 * time. The optional _align parameter can be used to force a
15*54fd6939SJiyong Park	 * non-standard alignment (indicated in powers of 2). The default is
16*54fd6939SJiyong Park	 * _align=2 because both Aarch32 and Aarch64 instructions must be
17*54fd6939SJiyong Park	 * word aligned. Do *not* try to use a raw .align directive. Since func
18*54fd6939SJiyong Park	 * switches to a new section, this would not have the desired effect.
19*54fd6939SJiyong Park	 */
20*54fd6939SJiyong Park	.macro func _name, _align=2
21*54fd6939SJiyong Park	/*
22*54fd6939SJiyong Park	 * Add Call Frame Information entry in the .debug_frame section for
23*54fd6939SJiyong Park	 * debugger consumption. This enables callstack printing in debuggers.
24*54fd6939SJiyong Park	 * This does not use any space in the final loaded binary, only in the
25*54fd6939SJiyong Park	 * ELF file.
26*54fd6939SJiyong Park	 * Note that a function manipulating the CFA pointer location (i.e. the
27*54fd6939SJiyong Park	 * x29 frame pointer on AArch64) should declare it using the
28*54fd6939SJiyong Park	 * appropriate .cfi* directives, or be prepared to have a degraded
29*54fd6939SJiyong Park	 * debugging experience.
30*54fd6939SJiyong Park	 */
31*54fd6939SJiyong Park	.cfi_sections .debug_frame
32*54fd6939SJiyong Park	.section .text.asm.\_name, "ax"
33*54fd6939SJiyong Park	.type \_name, %function
34*54fd6939SJiyong Park	/*
35*54fd6939SJiyong Park	 * .cfi_startproc and .cfi_endproc are needed to output entries in
36*54fd6939SJiyong Park	 * .debug_frame
37*54fd6939SJiyong Park	 */
38*54fd6939SJiyong Park	.cfi_startproc
39*54fd6939SJiyong Park	.align \_align
40*54fd6939SJiyong Park	\_name:
41*54fd6939SJiyong Park#if ENABLE_BTI
42*54fd6939SJiyong Park	/* When Branch Target Identification is enabled, insert "bti jc"
43*54fd6939SJiyong Park	 * instruction to enable indirect calls and branches
44*54fd6939SJiyong Park	 */
45*54fd6939SJiyong Park	 bti	jc
46*54fd6939SJiyong Park#endif
47*54fd6939SJiyong Park	.endm
48*54fd6939SJiyong Park
49*54fd6939SJiyong Park	/*
50*54fd6939SJiyong Park	 * This macro is used to mark the end of a function.
51*54fd6939SJiyong Park	 */
52*54fd6939SJiyong Park	.macro endfunc _name
53*54fd6939SJiyong Park	.cfi_endproc
54*54fd6939SJiyong Park	.size \_name, . - \_name
55*54fd6939SJiyong Park	.endm
56*54fd6939SJiyong Park
57*54fd6939SJiyong Park	/*
58*54fd6939SJiyong Park	 * Theses macros are used to create function labels for deprecated
59*54fd6939SJiyong Park	 * APIs. If ERROR_DEPRECATED is non zero, the callers of these APIs
60*54fd6939SJiyong Park	 * will fail to link and cause build failure.
61*54fd6939SJiyong Park	 */
62*54fd6939SJiyong Park#if ERROR_DEPRECATED
63*54fd6939SJiyong Park	.macro func_deprecated _name
64*54fd6939SJiyong Park	func deprecated\_name
65*54fd6939SJiyong Park	.endm
66*54fd6939SJiyong Park
67*54fd6939SJiyong Park	.macro endfunc_deprecated _name
68*54fd6939SJiyong Park	endfunc deprecated\_name
69*54fd6939SJiyong Park	.endm
70*54fd6939SJiyong Park#else
71*54fd6939SJiyong Park	.macro func_deprecated _name
72*54fd6939SJiyong Park	func \_name
73*54fd6939SJiyong Park	.endm
74*54fd6939SJiyong Park
75*54fd6939SJiyong Park	.macro endfunc_deprecated _name
76*54fd6939SJiyong Park	endfunc \_name
77*54fd6939SJiyong Park	.endm
78*54fd6939SJiyong Park#endif
79*54fd6939SJiyong Park
80*54fd6939SJiyong Park	/*
81*54fd6939SJiyong Park	 * Helper assembler macro to count trailing zeros. The output is
82*54fd6939SJiyong Park	 * populated in the `TZ_COUNT` symbol.
83*54fd6939SJiyong Park	 */
84*54fd6939SJiyong Park	.macro count_tz _value, _tz_count
85*54fd6939SJiyong Park	.if \_value
86*54fd6939SJiyong Park	  count_tz "(\_value >> 1)", "(\_tz_count + 1)"
87*54fd6939SJiyong Park	.else
88*54fd6939SJiyong Park	  .equ TZ_COUNT, (\_tz_count - 1)
89*54fd6939SJiyong Park	.endif
90*54fd6939SJiyong Park	.endm
91*54fd6939SJiyong Park
92*54fd6939SJiyong Park	/*
93*54fd6939SJiyong Park	 * This macro declares an array of 1 or more stacks, properly
94*54fd6939SJiyong Park	 * aligned and in the requested section
95*54fd6939SJiyong Park	 */
96*54fd6939SJiyong Park#define DEFAULT_STACK_ALIGN	(1 << 6)   /* In case the caller doesnt provide alignment */
97*54fd6939SJiyong Park
98*54fd6939SJiyong Park	.macro declare_stack _name, _section, _size, _count, _align=DEFAULT_STACK_ALIGN
99*54fd6939SJiyong Park	count_tz \_align, 0
100*54fd6939SJiyong Park	.if (\_align - (1 << TZ_COUNT))
101*54fd6939SJiyong Park	  .error "Incorrect stack alignment specified (Must be a power of 2)."
102*54fd6939SJiyong Park	.endif
103*54fd6939SJiyong Park	.if ((\_size & ((1 << TZ_COUNT) - 1)) <> 0)
104*54fd6939SJiyong Park	  .error "Stack size not correctly aligned"
105*54fd6939SJiyong Park	.endif
106*54fd6939SJiyong Park	.section    \_section, "aw", %nobits
107*54fd6939SJiyong Park	.align TZ_COUNT
108*54fd6939SJiyong Park	\_name:
109*54fd6939SJiyong Park	.space ((\_count) * (\_size)), 0
110*54fd6939SJiyong Park	.endm
111*54fd6939SJiyong Park
112*54fd6939SJiyong Park
113*54fd6939SJiyong Park#endif /* ASM_MACROS_COMMON_S */
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