1 /* 2 * Just-In-Time compiler for BPF filters on MIPS 3 * 4 * Copyright (c) 2014 Imagination Technologies Ltd. 5 * Author: Markos Chandras <markos.chandras@imgtec.com> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the 9 * Free Software Foundation; version 2 of the License. 10 */ 11 12 #ifndef BPF_JIT_MIPS_OP_H 13 #define BPF_JIT_MIPS_OP_H 14 15 /* Registers used by JIT */ 16 #define MIPS_R_ZERO 0 17 #define MIPS_R_V0 2 18 #define MIPS_R_A0 4 19 #define MIPS_R_A1 5 20 #define MIPS_R_T4 12 21 #define MIPS_R_T5 13 22 #define MIPS_R_T6 14 23 #define MIPS_R_T7 15 24 #define MIPS_R_S0 16 25 #define MIPS_R_S1 17 26 #define MIPS_R_S2 18 27 #define MIPS_R_S3 19 28 #define MIPS_R_S4 20 29 #define MIPS_R_S5 21 30 #define MIPS_R_S6 22 31 #define MIPS_R_S7 23 32 #define MIPS_R_SP 29 33 #define MIPS_R_RA 31 34 35 /* Conditional codes */ 36 #define MIPS_COND_EQ 0x1 37 #define MIPS_COND_GE (0x1 << 1) 38 #define MIPS_COND_GT (0x1 << 2) 39 #define MIPS_COND_NE (0x1 << 3) 40 #define MIPS_COND_ALL (0x1 << 4) 41 /* Conditionals on X register or K immediate */ 42 #define MIPS_COND_X (0x1 << 5) 43 #define MIPS_COND_K (0x1 << 6) 44 45 #define r_ret MIPS_R_V0 46 47 /* 48 * Use 2 scratch registers to avoid pipeline interlocks. 49 * There is no overhead during epilogue and prologue since 50 * any of the $s0-$s6 registers will only be preserved if 51 * they are going to actually be used. 52 */ 53 #define r_skb_hl MIPS_R_S0 /* skb header length */ 54 #define r_skb_data MIPS_R_S1 /* skb actual data */ 55 #define r_off MIPS_R_S2 56 #define r_A MIPS_R_S3 57 #define r_X MIPS_R_S4 58 #define r_skb MIPS_R_S5 59 #define r_M MIPS_R_S6 60 #define r_skb_len MIPS_R_S7 61 #define r_s0 MIPS_R_T4 /* scratch reg 1 */ 62 #define r_s1 MIPS_R_T5 /* scratch reg 2 */ 63 #define r_tmp_imm MIPS_R_T6 /* No need to preserve this */ 64 #define r_tmp MIPS_R_T7 /* No need to preserve this */ 65 #define r_zero MIPS_R_ZERO 66 #define r_sp MIPS_R_SP 67 #define r_ra MIPS_R_RA 68 69 #ifndef __ASSEMBLY__ 70 71 /* Declare ASM helpers */ 72 73 #define DECLARE_LOAD_FUNC(func) \ 74 extern u8 func(unsigned long *skb, int offset); \ 75 extern u8 func##_negative(unsigned long *skb, int offset); \ 76 extern u8 func##_positive(unsigned long *skb, int offset) 77 78 DECLARE_LOAD_FUNC(sk_load_word); 79 DECLARE_LOAD_FUNC(sk_load_half); 80 DECLARE_LOAD_FUNC(sk_load_byte); 81 82 #endif 83 84 #endif /* BPF_JIT_MIPS_OP_H */ 85