xref: /linux/arch/mips/mm/uasm-micromips.c (revision 597473720f4dc69749542bfcfed4a927a43d935e)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * A small micro-assembler. It is intentionally kept simple, does only
7  * support a subset of instructions, and does not try to hide pipeline
8  * effects like branch delay slots.
9  *
10  * Copyright (C) 2004, 2005, 2006, 2008	 Thiemo Seufer
11  * Copyright (C) 2005, 2007  Maciej W. Rozycki
12  * Copyright (C) 2006  Ralf Baechle (ralf@linux-mips.org)
13  * Copyright (C) 2012, 2013   MIPS Technologies, Inc.  All rights reserved.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/types.h>
18 
19 #include <asm/inst.h>
20 #include <asm/elf.h>
21 #include <asm/bugs.h>
22 #include <asm/uasm.h>
23 
24 #define RS_MASK		0x1f
25 #define RS_SH		16
26 #define RT_MASK		0x1f
27 #define RT_SH		21
28 #define SCIMM_MASK	0x3ff
29 #define SCIMM_SH	16
30 
31 /* This macro sets the non-variable bits of an instruction. */
32 #define M(a, b, c, d, e, f)					\
33 	((a) << OP_SH						\
34 	 | (b) << RT_SH						\
35 	 | (c) << RS_SH						\
36 	 | (d) << RD_SH						\
37 	 | (e) << RE_SH						\
38 	 | (f) << FUNC_SH)
39 
40 #include "uasm.c"
41 
42 static const struct insn insn_table_MM[insn_invalid] = {
43 	[insn_addu]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_addu32_op), RT | RS | RD},
44 	[insn_addiu]	= {M(mm_addiu32_op, 0, 0, 0, 0, 0), RT | RS | SIMM},
45 	[insn_and]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_and_op), RT | RS | RD},
46 	[insn_andi]	= {M(mm_andi32_op, 0, 0, 0, 0, 0), RT | RS | UIMM},
47 	[insn_beq]	= {M(mm_beq32_op, 0, 0, 0, 0, 0), RS | RT | BIMM},
48 	[insn_beql]	= {0, 0},
49 	[insn_bgez]	= {M(mm_pool32i_op, mm_bgez_op, 0, 0, 0, 0), RS | BIMM},
50 	[insn_bgezl]	= {0, 0},
51 	[insn_bltz]	= {M(mm_pool32i_op, mm_bltz_op, 0, 0, 0, 0), RS | BIMM},
52 	[insn_bltzl]	= {0, 0},
53 	[insn_bne]	= {M(mm_bne32_op, 0, 0, 0, 0, 0), RT | RS | BIMM},
54 	[insn_cache]	= {M(mm_pool32b_op, 0, 0, mm_cache_func, 0, 0), RT | RS | SIMM},
55 	[insn_cfc1]	= {M(mm_pool32f_op, 0, 0, 0, mm_cfc1_op, mm_32f_73_op), RT | RS},
56 	[insn_cfcmsa]	= {M(mm_pool32s_op, 0, msa_cfc_op, 0, 0, mm_32s_elm_op), RD | RE},
57 	[insn_ctc1]	= {M(mm_pool32f_op, 0, 0, 0, mm_ctc1_op, mm_32f_73_op), RT | RS},
58 	[insn_ctcmsa]	= {M(mm_pool32s_op, 0, msa_ctc_op, 0, 0, mm_32s_elm_op), RD | RE},
59 	[insn_daddu]	= {0, 0},
60 	[insn_daddiu]	= {0, 0},
61 	[insn_di]	= {M(mm_pool32a_op, 0, 0, 0, mm_di_op, mm_pool32axf_op), RS},
62 	[insn_divu]	= {M(mm_pool32a_op, 0, 0, 0, mm_divu_op, mm_pool32axf_op), RT | RS},
63 	[insn_dmfc0]	= {0, 0},
64 	[insn_dmtc0]	= {0, 0},
65 	[insn_dsll]	= {0, 0},
66 	[insn_dsll32]	= {0, 0},
67 	[insn_dsra]	= {0, 0},
68 	[insn_dsrl]	= {0, 0},
69 	[insn_dsrl32]	= {0, 0},
70 	[insn_drotr]	= {0, 0},
71 	[insn_drotr32]	= {0, 0},
72 	[insn_dsubu]	= {0, 0},
73 	[insn_eret]	= {M(mm_pool32a_op, 0, 0, 0, mm_eret_op, mm_pool32axf_op), 0},
74 	[insn_ins]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_ins_op), RT | RS | RD | RE},
75 	[insn_ext]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_ext_op), RT | RS | RD | RE},
76 	[insn_j]	= {M(mm_j32_op, 0, 0, 0, 0, 0), JIMM},
77 	[insn_jal]	= {M(mm_jal32_op, 0, 0, 0, 0, 0), JIMM},
78 	[insn_jalr]	= {M(mm_pool32a_op, 0, 0, 0, mm_jalr_op, mm_pool32axf_op), RT | RS},
79 	[insn_jr]	= {M(mm_pool32a_op, 0, 0, 0, mm_jalr_op, mm_pool32axf_op), RS},
80 	[insn_lb]	= {M(mm_lb32_op, 0, 0, 0, 0, 0), RT | RS | SIMM},
81 	[insn_ld]	= {0, 0},
82 	[insn_lh]	= {M(mm_lh32_op, 0, 0, 0, 0, 0), RT | RS | SIMM},
83 	[insn_ll]	= {M(mm_pool32c_op, 0, 0, (mm_ll_func << 1), 0, 0), RS | RT | SIMM},
84 	[insn_lld]	= {0, 0},
85 	[insn_lui]	= {M(mm_pool32i_op, mm_lui_op, 0, 0, 0, 0), RS | SIMM},
86 	[insn_lw]	= {M(mm_lw32_op, 0, 0, 0, 0, 0), RT | RS | SIMM},
87 	[insn_mfc0]	= {M(mm_pool32a_op, 0, 0, 0, mm_mfc0_op, mm_pool32axf_op), RT | RS | RD},
88 	[insn_mfhi]	= {M(mm_pool32a_op, 0, 0, 0, mm_mfhi32_op, mm_pool32axf_op), RS},
89 	[insn_mflo]	= {M(mm_pool32a_op, 0, 0, 0, mm_mflo32_op, mm_pool32axf_op), RS},
90 	[insn_mtc0]	= {M(mm_pool32a_op, 0, 0, 0, mm_mtc0_op, mm_pool32axf_op), RT | RS | RD},
91 	[insn_mthi]	= {M(mm_pool32a_op, 0, 0, 0, mm_mthi32_op, mm_pool32axf_op), RS},
92 	[insn_mtlo]	= {M(mm_pool32a_op, 0, 0, 0, mm_mtlo32_op, mm_pool32axf_op), RS},
93 	[insn_mul]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_mul_op), RT | RS | RD},
94 	[insn_or]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_or32_op), RT | RS | RD},
95 	[insn_ori]	= {M(mm_ori32_op, 0, 0, 0, 0, 0), RT | RS | UIMM},
96 	[insn_pref]	= {M(mm_pool32c_op, 0, 0, (mm_pref_func << 1), 0, 0), RT | RS | SIMM},
97 	[insn_rfe]	= {0, 0},
98 	[insn_sc]	= {M(mm_pool32c_op, 0, 0, (mm_sc_func << 1), 0, 0), RT | RS | SIMM},
99 	[insn_scd]	= {0, 0},
100 	[insn_sd]	= {0, 0},
101 	[insn_sll]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_sll32_op), RT | RS | RD},
102 	[insn_sllv]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_sllv32_op), RT | RS | RD},
103 	[insn_slt]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_slt_op), RT | RS | RD},
104 	[insn_sltiu]	= {M(mm_sltiu32_op, 0, 0, 0, 0, 0), RT | RS | SIMM},
105 	[insn_sltu]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_sltu_op), RT | RS | RD},
106 	[insn_sra]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_sra_op), RT | RS | RD},
107 	[insn_srav]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_srav_op), RT | RS | RD},
108 	[insn_srl]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_srl32_op), RT | RS | RD},
109 	[insn_srlv]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_srlv32_op), RT | RS | RD},
110 	[insn_rotr]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_rotr_op), RT | RS | RD},
111 	[insn_subu]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_subu32_op), RT | RS | RD},
112 	[insn_sw]	= {M(mm_sw32_op, 0, 0, 0, 0, 0), RT | RS | SIMM},
113 	[insn_sync]	= {M(mm_pool32a_op, 0, 0, 0, mm_sync_op, mm_pool32axf_op), RS},
114 	[insn_tlbp]	= {M(mm_pool32a_op, 0, 0, 0, mm_tlbp_op, mm_pool32axf_op), 0},
115 	[insn_tlbr]	= {M(mm_pool32a_op, 0, 0, 0, mm_tlbr_op, mm_pool32axf_op), 0},
116 	[insn_tlbwi]	= {M(mm_pool32a_op, 0, 0, 0, mm_tlbwi_op, mm_pool32axf_op), 0},
117 	[insn_tlbwr]	= {M(mm_pool32a_op, 0, 0, 0, mm_tlbwr_op, mm_pool32axf_op), 0},
118 	[insn_wait]	= {M(mm_pool32a_op, 0, 0, 0, mm_wait_op, mm_pool32axf_op), SCIMM},
119 	[insn_wsbh]	= {M(mm_pool32a_op, 0, 0, 0, mm_wsbh_op, mm_pool32axf_op), RT | RS},
120 	[insn_xor]	= {M(mm_pool32a_op, 0, 0, 0, 0, mm_xor32_op), RT | RS | RD},
121 	[insn_xori]	= {M(mm_xori32_op, 0, 0, 0, 0, 0), RT | RS | UIMM},
122 	[insn_dins]	= {0, 0},
123 	[insn_dinsm]	= {0, 0},
124 	[insn_syscall]	= {M(mm_pool32a_op, 0, 0, 0, mm_syscall_op, mm_pool32axf_op), SCIMM},
125 	[insn_bbit0]	= {0, 0},
126 	[insn_bbit1]	= {0, 0},
127 	[insn_lwx]	= {0, 0},
128 	[insn_ldx]	= {0, 0},
129 };
130 
131 #undef M
132 
build_bimm(s32 arg)133 static inline u32 build_bimm(s32 arg)
134 {
135 	WARN(arg > 0xffff || arg < -0x10000,
136 	     KERN_WARNING "Micro-assembler field overflow\n");
137 
138 	WARN(arg & 0x3, KERN_WARNING "Invalid micro-assembler branch target\n");
139 
140 	return ((arg < 0) ? (1 << 15) : 0) | ((arg >> 1) & 0x7fff);
141 }
142 
build_jimm(u32 arg)143 static inline u32 build_jimm(u32 arg)
144 {
145 
146 	WARN(arg & ~((JIMM_MASK << 2) | 1),
147 	     KERN_WARNING "Micro-assembler field overflow\n");
148 
149 	return (arg >> 1) & JIMM_MASK;
150 }
151 
152 /*
153  * The order of opcode arguments is implicitly left to right,
154  * starting with RS and ending with FUNC or IMM.
155  */
build_insn(u32 ** buf,enum opcode opc,...)156 static void build_insn(u32 **buf, enum opcode opc, ...)
157 {
158 	const struct insn *ip;
159 	va_list ap;
160 	u32 op;
161 
162 	if (opc < 0 || opc >= insn_invalid ||
163 	    (opc == insn_daddiu && r4k_daddiu_bug()) ||
164 	    (insn_table_MM[opc].match == 0 && insn_table_MM[opc].fields == 0))
165 		panic("Unsupported Micro-assembler instruction %d", opc);
166 
167 	ip = &insn_table_MM[opc];
168 
169 	op = ip->match;
170 	va_start(ap, opc);
171 	if (ip->fields & RS) {
172 		if (opc == insn_mfc0 || opc == insn_mtc0 ||
173 		    opc == insn_cfc1 || opc == insn_ctc1)
174 			op |= build_rt(va_arg(ap, u32));
175 		else
176 			op |= build_rs(va_arg(ap, u32));
177 	}
178 	if (ip->fields & RT) {
179 		if (opc == insn_mfc0 || opc == insn_mtc0 ||
180 		    opc == insn_cfc1 || opc == insn_ctc1)
181 			op |= build_rs(va_arg(ap, u32));
182 		else
183 			op |= build_rt(va_arg(ap, u32));
184 	}
185 	if (ip->fields & RD)
186 		op |= build_rd(va_arg(ap, u32));
187 	if (ip->fields & RE)
188 		op |= build_re(va_arg(ap, u32));
189 	if (ip->fields & SIMM)
190 		op |= build_simm(va_arg(ap, s32));
191 	if (ip->fields & UIMM)
192 		op |= build_uimm(va_arg(ap, u32));
193 	if (ip->fields & BIMM)
194 		op |= build_bimm(va_arg(ap, s32));
195 	if (ip->fields & JIMM)
196 		op |= build_jimm(va_arg(ap, u32));
197 	if (ip->fields & FUNC)
198 		op |= build_func(va_arg(ap, u32));
199 	if (ip->fields & SET)
200 		op |= build_set(va_arg(ap, u32));
201 	if (ip->fields & SCIMM)
202 		op |= build_scimm(va_arg(ap, u32));
203 	va_end(ap);
204 
205 #ifdef CONFIG_CPU_LITTLE_ENDIAN
206 	**buf = ((op & 0xffff) << 16) | (op >> 16);
207 #else
208 	**buf = op;
209 #endif
210 	(*buf)++;
211 }
212 
213 static inline void
__resolve_relocs(struct uasm_reloc * rel,struct uasm_label * lab)214 __resolve_relocs(struct uasm_reloc *rel, struct uasm_label *lab)
215 {
216 	long laddr = (long)lab->addr;
217 	long raddr = (long)rel->addr;
218 
219 	switch (rel->type) {
220 	case R_MIPS_PC16:
221 #ifdef CONFIG_CPU_LITTLE_ENDIAN
222 		*rel->addr |= (build_bimm(laddr - (raddr + 4)) << 16);
223 #else
224 		*rel->addr |= build_bimm(laddr - (raddr + 4));
225 #endif
226 		break;
227 
228 	default:
229 		panic("Unsupported Micro-assembler relocation %d",
230 		      rel->type);
231 	}
232 }
233