drm/panthor: Don't add write fences to the shared BOs
[drm/drm-misc.git] / arch / mips / include / asm / vdso / vdso.h
blob6cd88191fefa9ce6d8323dd70d45aa9a198ac9d0
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Copyright (C) 2015 Imagination Technologies
4 * Author: Alex Smith <alex.smith@imgtec.com>
5 */
7 #include <asm/sgidefs.h>
9 #ifndef __ASSEMBLY__
11 #include <asm/asm.h>
12 #include <asm/page.h>
13 #include <asm/vdso.h>
15 static inline unsigned long get_vdso_base(void)
17 unsigned long addr;
20 * We can't use cpu_has_mips_r6 since it needs the cpu_data[]
21 * kernel symbol.
23 #ifdef CONFIG_CPU_MIPSR6
25 * lapc <symbol> is an alias to addiupc reg, <symbol> - .
27 * We can't use addiupc because there is no label-label
28 * support for the addiupc reloc
30 __asm__("lapc %0, _start \n"
31 : "=r" (addr) : :);
32 #else
34 * Get the base load address of the VDSO. We have to avoid generating
35 * relocations and references to the GOT because ld.so does not perform
36 * relocations on the VDSO. We use the current offset from the VDSO base
37 * and perform a PC-relative branch which gives the absolute address in
38 * ra, and take the difference. The assembler chokes on
39 * "li %0, _start - .", so embed the offset as a word and branch over
40 * it.
44 __asm__(
45 " .set push \n"
46 " .set noreorder \n"
47 " bal 1f \n"
48 " nop \n"
49 " .word _start - . \n"
50 "1: lw %0, 0($31) \n"
51 " " STR(PTR_ADDU) " %0, $31, %0 \n"
52 " .set pop \n"
53 : "=r" (addr)
55 : "$31");
56 #endif /* CONFIG_CPU_MIPSR6 */
58 return addr;
61 static inline const struct vdso_data *get_vdso_data(void)
63 return (const struct vdso_data *)(get_vdso_base() - PAGE_SIZE);
66 #ifdef CONFIG_CLKSRC_MIPS_GIC
68 static inline void __iomem *get_gic(const struct vdso_data *data)
70 return (void __iomem *)((unsigned long)data & PAGE_MASK) - PAGE_SIZE;
73 #endif /* CONFIG_CLKSRC_MIPS_GIC */
75 #endif /* __ASSEMBLY__ */