Zhigang Lu | 65a792e | 2015-09-30 10:11:45 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 Tilera Corporation. All Rights Reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation, version 2. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but |
| 9 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| 11 | * NON INFRINGEMENT. See the GNU General Public License for |
| 12 | * more details. |
| 13 | * |
| 14 | * jump label TILE-Gx support |
| 15 | */ |
| 16 | |
| 17 | #include <linux/jump_label.h> |
| 18 | #include <linux/memory.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/mutex.h> |
| 21 | #include <linux/cpu.h> |
| 22 | |
| 23 | #include <asm/cacheflush.h> |
| 24 | #include <asm/insn.h> |
| 25 | |
| 26 | #ifdef HAVE_JUMP_LABEL |
| 27 | |
| 28 | static void __jump_label_transform(struct jump_entry *e, |
| 29 | enum jump_label_type type) |
| 30 | { |
| 31 | tilegx_bundle_bits opcode; |
| 32 | /* Operate on writable kernel text mapping. */ |
| 33 | unsigned long pc_wr = ktext_writable_addr(e->code); |
| 34 | |
| 35 | if (type == JUMP_LABEL_JMP) |
| 36 | opcode = tilegx_gen_branch(e->code, e->target, false); |
| 37 | else |
| 38 | opcode = NOP(); |
| 39 | |
| 40 | *(tilegx_bundle_bits *)pc_wr = opcode; |
| 41 | /* Make sure that above mem writes were issued towards the memory. */ |
| 42 | smp_wmb(); |
| 43 | } |
| 44 | |
| 45 | void arch_jump_label_transform(struct jump_entry *e, |
| 46 | enum jump_label_type type) |
| 47 | { |
| 48 | get_online_cpus(); |
| 49 | mutex_lock(&text_mutex); |
| 50 | |
| 51 | __jump_label_transform(e, type); |
| 52 | flush_icache_range(e->code, e->code + sizeof(tilegx_bundle_bits)); |
| 53 | |
| 54 | mutex_unlock(&text_mutex); |
| 55 | put_online_cpus(); |
| 56 | } |
| 57 | |
| 58 | __init_or_module void arch_jump_label_transform_static(struct jump_entry *e, |
| 59 | enum jump_label_type type) |
| 60 | { |
| 61 | __jump_label_transform(e, type); |
| 62 | } |
| 63 | |
| 64 | #endif /* HAVE_JUMP_LABEL */ |