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
42static 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
133static 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
143static 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 */
156static 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
213static inline void
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