| /* |
| * Copyright (C) 2015 Imagination Technologies |
| * Author: Alex Smith <alex.smith@imgtec.com> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the |
| * Free Software Foundation; either version 2 of the License, or (at your |
| * option) any later version. |
| */ |
| |
| #include <asm/sgidefs.h> |
| |
| #if _MIPS_SIM != _MIPS_SIM_ABI64 && defined(CONFIG_64BIT) |
| |
| /* Building 32-bit VDSO for the 64-bit kernel. Fake a 32-bit Kconfig. */ |
| #undef CONFIG_64BIT |
| #define CONFIG_32BIT 1 |
| #ifndef __ASSEMBLY__ |
| #include <asm-generic/atomic64.h> |
| #endif |
| #endif |
| |
| #ifndef __ASSEMBLY__ |
| |
| #include <asm/asm.h> |
| #include <asm/page.h> |
| #include <asm/vdso.h> |
| |
| static inline unsigned long get_vdso_base(void) |
| { |
| unsigned long addr; |
| |
| /* |
| * We can't use cpu_has_mips_r6 since it needs the cpu_data[] |
| * kernel symbol. |
| */ |
| #ifdef CONFIG_CPU_MIPSR6 |
| /* |
| * lapc <symbol> is an alias to addiupc reg, <symbol> - . |
| * |
| * We can't use addiupc because there is no label-label |
| * support for the addiupc reloc |
| */ |
| __asm__("lapc %0, _start \n" |
| : "=r" (addr) : :); |
| #else |
| /* |
| * Get the base load address of the VDSO. We have to avoid generating |
| * relocations and references to the GOT because ld.so does not peform |
| * relocations on the VDSO. We use the current offset from the VDSO base |
| * and perform a PC-relative branch which gives the absolute address in |
| * ra, and take the difference. The assembler chokes on |
| * "li %0, _start - .", so embed the offset as a word and branch over |
| * it. |
| * |
| */ |
| |
| __asm__( |
| " .set push \n" |
| " .set noreorder \n" |
| " bal 1f \n" |
| " nop \n" |
| " .word _start - . \n" |
| "1: lw %0, 0($31) \n" |
| " " STR(PTR_ADDU) " %0, $31, %0 \n" |
| " .set pop \n" |
| : "=r" (addr) |
| : |
| : "$31"); |
| #endif /* CONFIG_CPU_MIPSR6 */ |
| |
| return addr; |
| } |
| |
| static inline const union mips_vdso_data *get_vdso_data(void) |
| { |
| return (const union mips_vdso_data *)(get_vdso_base() - PAGE_SIZE); |
| } |
| |
| #ifdef CONFIG_CLKSRC_MIPS_GIC |
| |
| static inline void __iomem *get_gic(const union mips_vdso_data *data) |
| { |
| return (void __iomem *)data - PAGE_SIZE; |
| } |
| |
| #endif /* CONFIG_CLKSRC_MIPS_GIC */ |
| |
| #endif /* __ASSEMBLY__ */ |