xref: /openbmc/qemu/linux-user/hppa/vdso.S (revision 259ebed4)
1/*
2 * hppa linux kernel vdso replacement.
3 *
4 * Copyright 2023 Linaro, Ltd.
5 *
6 * SPDX-License-Identifier: GPL-2.0-or-later
7 */
8
9#include <asm/unistd.h>
10#include "vdso-asmoffset.h"
11
12	.text
13
14
15/*
16 * arch/parisc/kernel/vdso32/sigtramp.S:
17 * Gdb expects the trampoline is on the stack and the pc is offset from
18 * a 64-byte boundary by 0, 4 or 5 instructions. Since the vdso trampoline
19 * is not on the stack, we need a new variant with different offsets and
20 * data to tell gdb where to find the signal context on the stack.
21 *
22 * Here we put the offset to the context data at the start of the trampoline
23 * region and offset the first trampoline by 2 instructions. Please do
24 * not change the trampoline as the code in gdb depends on the following
25 * instruction sequence exactly.
26 */
27
28/* arch/parisc/kernel/asm-offsets.c */
29#define SIGFRAME_CONTEXT_REGS32 \
30    (offsetof_sigcontext - PARISC_RT_SIGFRAME_SIZE32)
31
32        .align	64
33        .word	SIGFRAME_CONTEXT_REGS32
34
35/*
36 * All that said, we can provide a proper unwind record, which means that
37 * GDB should not actually need the offset magic.
38 *
39 * The return address that arrived here, from the inner frame, is
40 * not marked as a signal frame and so the unwinder still tries to
41 * subtract 1 to examine the presumed call insn.  Thus we must
42 * extend the unwind info to a nop before the start.
43 */
44
45	.cfi_startproc simple
46	.cfi_signal_frame
47
48	/* Compare pa32_fallback_frame_state from libgcc. */
49
50	/*
51	 * Place the CFA at the start of sigcontext for convenience.
52	 * The previous CFA will be restored from the saved stack pointer.
53	 */
54	.cfi_def_cfa	30, -PARISC_RT_SIGFRAME_SIZE32 + offsetof_sigcontext
55
56	/* Record save offset of general registers. */
57	.cfi_offset	1, offsetof_sigcontext_gr + 1 * 4
58	.cfi_offset	2, offsetof_sigcontext_gr + 2 * 4
59	.cfi_offset	3, offsetof_sigcontext_gr + 3 * 4
60	.cfi_offset	4, offsetof_sigcontext_gr + 4 * 4
61	.cfi_offset	5, offsetof_sigcontext_gr + 5 * 4
62	.cfi_offset	6, offsetof_sigcontext_gr + 6 * 4
63	.cfi_offset	7, offsetof_sigcontext_gr + 7 * 4
64	.cfi_offset	8, offsetof_sigcontext_gr + 8 * 4
65	.cfi_offset	9, offsetof_sigcontext_gr + 9 * 4
66	.cfi_offset	10, offsetof_sigcontext_gr + 10 * 4
67	.cfi_offset	11, offsetof_sigcontext_gr + 11 * 4
68	.cfi_offset	12, offsetof_sigcontext_gr + 12 * 4
69	.cfi_offset	13, offsetof_sigcontext_gr + 13 * 4
70	.cfi_offset	14, offsetof_sigcontext_gr + 14 * 4
71	.cfi_offset	15, offsetof_sigcontext_gr + 15 * 4
72	.cfi_offset	16, offsetof_sigcontext_gr + 16 * 4
73	.cfi_offset	17, offsetof_sigcontext_gr + 17 * 4
74	.cfi_offset	18, offsetof_sigcontext_gr + 18 * 4
75	.cfi_offset	19, offsetof_sigcontext_gr + 19 * 4
76	.cfi_offset	20, offsetof_sigcontext_gr + 20 * 4
77	.cfi_offset	21, offsetof_sigcontext_gr + 21 * 4
78	.cfi_offset	22, offsetof_sigcontext_gr + 22 * 4
79	.cfi_offset	23, offsetof_sigcontext_gr + 23 * 4
80	.cfi_offset	24, offsetof_sigcontext_gr + 24 * 4
81	.cfi_offset	25, offsetof_sigcontext_gr + 25 * 4
82	.cfi_offset	26, offsetof_sigcontext_gr + 26 * 4
83	.cfi_offset	27, offsetof_sigcontext_gr + 27 * 4
84	.cfi_offset	28, offsetof_sigcontext_gr + 28 * 4
85	.cfi_offset	29, offsetof_sigcontext_gr + 29 * 4
86	.cfi_offset	30, offsetof_sigcontext_gr + 30 * 4
87	.cfi_offset	31, offsetof_sigcontext_gr + 31 * 4
88
89	/* Record save offset of fp registers, left and right halves. */
90	.cfi_offset	32, offsetof_sigcontext_fr + 4 * 8
91	.cfi_offset	33, offsetof_sigcontext_fr + 4 * 8 + 4
92	.cfi_offset	34, offsetof_sigcontext_fr + 5 * 8
93	.cfi_offset	35, offsetof_sigcontext_fr + 5 * 8 + 4
94	.cfi_offset	36, offsetof_sigcontext_fr + 6 * 8
95	.cfi_offset	37, offsetof_sigcontext_fr + 6 * 8 + 4
96	.cfi_offset	38, offsetof_sigcontext_fr + 7 * 8
97	.cfi_offset	39, offsetof_sigcontext_fr + 7 * 8 + 4
98	.cfi_offset	40, offsetof_sigcontext_fr + 8 * 8
99	.cfi_offset	41, offsetof_sigcontext_fr + 8 * 8 + 4
100	.cfi_offset	42, offsetof_sigcontext_fr + 9 * 8
101	.cfi_offset	43, offsetof_sigcontext_fr + 9 * 8 + 4
102	.cfi_offset	44, offsetof_sigcontext_fr + 10 * 8
103	.cfi_offset	45, offsetof_sigcontext_fr + 10 * 8 + 4
104	.cfi_offset	46, offsetof_sigcontext_fr + 11 * 8
105	.cfi_offset	47, offsetof_sigcontext_fr + 11 * 8 + 4
106	.cfi_offset	48, offsetof_sigcontext_fr + 12 * 8
107	.cfi_offset	49, offsetof_sigcontext_fr + 12 * 8 + 4
108	.cfi_offset	50, offsetof_sigcontext_fr + 13 * 8
109	.cfi_offset	51, offsetof_sigcontext_fr + 13 * 8 + 4
110	.cfi_offset	52, offsetof_sigcontext_fr + 14 * 8
111	.cfi_offset	53, offsetof_sigcontext_fr + 14 * 8 + 4
112	.cfi_offset	54, offsetof_sigcontext_fr + 15 * 8
113	.cfi_offset	55, offsetof_sigcontext_fr + 15 * 8 + 4
114	.cfi_offset	56, offsetof_sigcontext_fr + 16 * 8
115	.cfi_offset	57, offsetof_sigcontext_fr + 16 * 8 + 4
116	.cfi_offset	58, offsetof_sigcontext_fr + 17 * 8
117	.cfi_offset	59, offsetof_sigcontext_fr + 17 * 8 + 4
118	.cfi_offset	60, offsetof_sigcontext_fr + 18 * 8
119	.cfi_offset	61, offsetof_sigcontext_fr + 18 * 8 + 4
120	.cfi_offset	62, offsetof_sigcontext_fr + 19 * 8
121	.cfi_offset	63, offsetof_sigcontext_fr + 19 * 8 + 4
122	.cfi_offset	64, offsetof_sigcontext_fr + 20 * 8
123	.cfi_offset	65, offsetof_sigcontext_fr + 20 * 8 + 4
124	.cfi_offset	66, offsetof_sigcontext_fr + 21 * 8
125	.cfi_offset	67, offsetof_sigcontext_fr + 21 * 8 + 4
126	.cfi_offset	68, offsetof_sigcontext_fr + 22 * 8
127	.cfi_offset	69, offsetof_sigcontext_fr + 22 * 8 + 4
128	.cfi_offset	70, offsetof_sigcontext_fr + 23 * 8
129	.cfi_offset	71, offsetof_sigcontext_fr + 23 * 8 + 4
130	.cfi_offset	72, offsetof_sigcontext_fr + 24 * 8
131	.cfi_offset	73, offsetof_sigcontext_fr + 24 * 8 + 4
132	.cfi_offset	74, offsetof_sigcontext_fr + 25 * 8
133	.cfi_offset	75, offsetof_sigcontext_fr + 25 * 8 + 4
134	.cfi_offset	76, offsetof_sigcontext_fr + 26 * 8
135	.cfi_offset	77, offsetof_sigcontext_fr + 26 * 8 + 4
136	.cfi_offset	78, offsetof_sigcontext_fr + 27 * 8
137	.cfi_offset	79, offsetof_sigcontext_fr + 27 * 8 + 4
138	.cfi_offset	80, offsetof_sigcontext_fr + 28 * 8
139	.cfi_offset	81, offsetof_sigcontext_fr + 28 * 8 + 4
140	.cfi_offset	82, offsetof_sigcontext_fr + 29 * 8
141	.cfi_offset	83, offsetof_sigcontext_fr + 29 * 8 + 4
142	.cfi_offset	84, offsetof_sigcontext_fr + 30 * 8
143	.cfi_offset	85, offsetof_sigcontext_fr + 30 * 8 + 4
144	.cfi_offset	86, offsetof_sigcontext_fr + 31 * 8
145	.cfi_offset	87, offsetof_sigcontext_fr + 31 * 8 + 4
146
147	/* Record save offset of %sar */
148	.cfi_offset	88, offsetof_sigcontext_sar
149
150	/* Record save offset of return address, iaoq[0]. */
151	.cfi_return_column 89
152	.cfi_offset	89, offsetof_sigcontext_iaoq
153
154	nop
155
156__kernel_sigtramp_rt:
157	ldi	0, %r25
158	ldi	__NR_rt_sigreturn, %r20
159	be,l	0x100(%sr2, %r0), %sr0, %r31
160	nop
161
162	.cfi_endproc
163	.size	__kernel_sigtramp_rt, . - __kernel_sigtramp_rt
164	.type	__kernel_sigtramp_rt, @function
165	.globl	__kernel_sigtramp_rt
166