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#define UASM_ISA	_UASM_ISA_CLASSIC
23#include <asm/uasm.h>
24
25#define RS_MASK		0x1f
26#define RS_SH		21
27#define RT_MASK		0x1f
28#define RT_SH		16
29#define SCIMM_MASK	0xfffff
30#define SCIMM_SH	6
31
32/* This macro sets the non-variable bits of an instruction. */
33#define M(a, b, c, d, e, f)					\
34	((a) << OP_SH						\
35	 | (b) << RS_SH						\
36	 | (c) << RT_SH						\
37	 | (d) << RD_SH						\
38	 | (e) << RE_SH						\
39	 | (f) << FUNC_SH)
40
41/* This macro sets the non-variable bits of an R6 instruction. */
42#define M6(a, b, c, d, e)					\
43	((a) << OP_SH						\
44	 | (b) << RS_SH						\
45	 | (c) << RT_SH						\
46	 | (d) << SIMM9_SH					\
47	 | (e) << FUNC_SH)
48
49#include "uasm.c"
50
51static struct insn insn_table[] = {
52	{ insn_addiu, M(addiu_op, 0, 0, 0, 0, 0), RS | RT | SIMM },
53	{ insn_addu, M(spec_op, 0, 0, 0, 0, addu_op), RS | RT | RD },
54	{ insn_andi, M(andi_op, 0, 0, 0, 0, 0), RS | RT | UIMM },
55	{ insn_and, M(spec_op, 0, 0, 0, 0, and_op), RS | RT | RD },
56	{ insn_bbit0, M(lwc2_op, 0, 0, 0, 0, 0), RS | RT | BIMM },
57	{ insn_bbit1, M(swc2_op, 0, 0, 0, 0, 0), RS | RT | BIMM },
58	{ insn_beql, M(beql_op, 0, 0, 0, 0, 0), RS | RT | BIMM },
59	{ insn_beq, M(beq_op, 0, 0, 0, 0, 0), RS | RT | BIMM },
60	{ insn_bgezl, M(bcond_op, 0, bgezl_op, 0, 0, 0), RS | BIMM },
61	{ insn_bgez, M(bcond_op, 0, bgez_op, 0, 0, 0), RS | BIMM },
62	{ insn_bltzl, M(bcond_op, 0, bltzl_op, 0, 0, 0), RS | BIMM },
63	{ insn_bltz, M(bcond_op, 0, bltz_op, 0, 0, 0), RS | BIMM },
64	{ insn_bne, M(bne_op, 0, 0, 0, 0, 0), RS | RT | BIMM },
65#ifndef CONFIG_CPU_MIPSR6
66	{ insn_cache,  M(cache_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
67#else
68	{ insn_cache,  M6(cache_op, 0, 0, 0, cache6_op),  RS | RT | SIMM9 },
69#endif
70	{ insn_daddiu, M(daddiu_op, 0, 0, 0, 0, 0), RS | RT | SIMM },
71	{ insn_daddu, M(spec_op, 0, 0, 0, 0, daddu_op), RS | RT | RD },
72	{ insn_dinsm, M(spec3_op, 0, 0, 0, 0, dinsm_op), RS | RT | RD | RE },
73	{ insn_dins, M(spec3_op, 0, 0, 0, 0, dins_op), RS | RT | RD | RE },
74	{ insn_divu, M(spec_op, 0, 0, 0, 0, divu_op), RS | RT },
75	{ insn_dmfc0, M(cop0_op, dmfc_op, 0, 0, 0, 0), RT | RD | SET},
76	{ insn_dmtc0, M(cop0_op, dmtc_op, 0, 0, 0, 0), RT | RD | SET},
77	{ insn_drotr32, M(spec_op, 1, 0, 0, 0, dsrl32_op), RT | RD | RE },
78	{ insn_drotr, M(spec_op, 1, 0, 0, 0, dsrl_op), RT | RD | RE },
79	{ insn_dsll32, M(spec_op, 0, 0, 0, 0, dsll32_op), RT | RD | RE },
80	{ insn_dsll, M(spec_op, 0, 0, 0, 0, dsll_op), RT | RD | RE },
81	{ insn_dsra, M(spec_op, 0, 0, 0, 0, dsra_op), RT | RD | RE },
82	{ insn_dsrl32, M(spec_op, 0, 0, 0, 0, dsrl32_op), RT | RD | RE },
83	{ insn_dsrl, M(spec_op, 0, 0, 0, 0, dsrl_op), RT | RD | RE },
84	{ insn_dsubu, M(spec_op, 0, 0, 0, 0, dsubu_op), RS | RT | RD },
85	{ insn_eret,  M(cop0_op, cop_op, 0, 0, 0, eret_op),  0 },
86	{ insn_ext, M(spec3_op, 0, 0, 0, 0, ext_op), RS | RT | RD | RE },
87	{ insn_ins, M(spec3_op, 0, 0, 0, 0, ins_op), RS | RT | RD | RE },
88	{ insn_j,  M(j_op, 0, 0, 0, 0, 0),  JIMM },
89	{ insn_jal,  M(jal_op, 0, 0, 0, 0, 0),	JIMM },
90	{ insn_jalr,  M(spec_op, 0, 0, 0, 0, jalr_op), RS | RD },
91	{ insn_j,  M(j_op, 0, 0, 0, 0, 0),  JIMM },
92#ifndef CONFIG_CPU_MIPSR6
93	{ insn_jr,  M(spec_op, 0, 0, 0, 0, jr_op),  RS },
94#else
95	{ insn_jr,  M(spec_op, 0, 0, 0, 0, jalr_op),  RS },
96#endif
97	{ insn_lb, M(lb_op, 0, 0, 0, 0, 0), RS | RT | SIMM },
98	{ insn_ld,  M(ld_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
99	{ insn_ldx, M(spec3_op, 0, 0, 0, ldx_op, lx_op), RS | RT | RD },
100	{ insn_lh,  M(lh_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
101#ifndef CONFIG_CPU_MIPSR6
102	{ insn_lld,  M(lld_op, 0, 0, 0, 0, 0),	RS | RT | SIMM },
103	{ insn_ll,  M(ll_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
104#else
105	{ insn_lld,  M6(spec3_op, 0, 0, 0, lld6_op),  RS | RT | SIMM9 },
106	{ insn_ll,  M6(spec3_op, 0, 0, 0, ll6_op),  RS | RT | SIMM9 },
107#endif
108	{ insn_lui,  M(lui_op, 0, 0, 0, 0, 0),	RT | SIMM },
109	{ insn_lw,  M(lw_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
110	{ insn_lwx, M(spec3_op, 0, 0, 0, lwx_op, lx_op), RS | RT | RD },
111	{ insn_mfc0,  M(cop0_op, mfc_op, 0, 0, 0, 0),  RT | RD | SET},
112	{ insn_mfhc0,  M(cop0_op, mfhc0_op, 0, 0, 0, 0),  RT | RD | SET},
113	{ insn_mfhi,  M(spec_op, 0, 0, 0, 0, mfhi_op), RD },
114	{ insn_mflo,  M(spec_op, 0, 0, 0, 0, mflo_op), RD },
115	{ insn_mtc0,  M(cop0_op, mtc_op, 0, 0, 0, 0),  RT | RD | SET},
116	{ insn_mthc0,  M(cop0_op, mthc0_op, 0, 0, 0, 0),  RT | RD | SET},
117	{ insn_mul, M(spec2_op, 0, 0, 0, 0, mul_op), RS | RT | RD},
118	{ insn_ori,  M(ori_op, 0, 0, 0, 0, 0),	RS | RT | UIMM },
119	{ insn_or,  M(spec_op, 0, 0, 0, 0, or_op),  RS | RT | RD },
120#ifndef CONFIG_CPU_MIPSR6
121	{ insn_pref,  M(pref_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
122#else
123	{ insn_pref,  M6(spec3_op, 0, 0, 0, pref6_op),  RS | RT | SIMM9 },
124#endif
125	{ insn_rfe,  M(cop0_op, cop_op, 0, 0, 0, rfe_op),  0 },
126	{ insn_rotr,  M(spec_op, 1, 0, 0, 0, srl_op),  RT | RD | RE },
127#ifndef CONFIG_CPU_MIPSR6
128	{ insn_scd,  M(scd_op, 0, 0, 0, 0, 0),	RS | RT | SIMM },
129	{ insn_sc,  M(sc_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
130#else
131	{ insn_scd,  M6(spec3_op, 0, 0, 0, scd6_op),  RS | RT | SIMM9 },
132	{ insn_sc,  M6(spec3_op, 0, 0, 0, sc6_op),  RS | RT | SIMM9 },
133#endif
134	{ insn_sd,  M(sd_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
135	{ insn_sll,  M(spec_op, 0, 0, 0, 0, sll_op),  RT | RD | RE },
136	{ insn_sllv,  M(spec_op, 0, 0, 0, 0, sllv_op),  RS | RT | RD },
137	{ insn_slt,  M(spec_op, 0, 0, 0, 0, slt_op),  RS | RT | RD },
138	{ insn_sltiu, M(sltiu_op, 0, 0, 0, 0, 0), RS | RT | SIMM },
139	{ insn_sltu, M(spec_op, 0, 0, 0, 0, sltu_op), RS | RT | RD },
140	{ insn_sra,  M(spec_op, 0, 0, 0, 0, sra_op),  RT | RD | RE },
141	{ insn_srl,  M(spec_op, 0, 0, 0, 0, srl_op),  RT | RD | RE },
142	{ insn_srlv,  M(spec_op, 0, 0, 0, 0, srlv_op),  RS | RT | RD },
143	{ insn_subu,  M(spec_op, 0, 0, 0, 0, subu_op),	RS | RT | RD },
144	{ insn_sw,  M(sw_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
145	{ insn_sync, M(spec_op, 0, 0, 0, 0, sync_op), RE },
146	{ insn_syscall, M(spec_op, 0, 0, 0, 0, syscall_op), SCIMM},
147	{ insn_tlbp,  M(cop0_op, cop_op, 0, 0, 0, tlbp_op),  0 },
148	{ insn_tlbr,  M(cop0_op, cop_op, 0, 0, 0, tlbr_op),  0 },
149	{ insn_tlbwi,  M(cop0_op, cop_op, 0, 0, 0, tlbwi_op),  0 },
150	{ insn_tlbwr,  M(cop0_op, cop_op, 0, 0, 0, tlbwr_op),  0 },
151	{ insn_wait, M(cop0_op, cop_op, 0, 0, 0, wait_op), SCIMM },
152	{ insn_wsbh, M(spec3_op, 0, 0, 0, wsbh_op, bshfl_op), RT | RD },
153	{ insn_xori,  M(xori_op, 0, 0, 0, 0, 0),  RS | RT | UIMM },
154	{ insn_xor,  M(spec_op, 0, 0, 0, 0, xor_op),  RS | RT | RD },
155	{ insn_yield, M(spec3_op, 0, 0, 0, 0, yield_op), RS | RD },
156	{ insn_invalid, 0, 0 }
157};
158
159#undef M
160
161static inline u32 build_bimm(s32 arg)
162{
163	WARN(arg > 0x1ffff || arg < -0x20000,
164	     KERN_WARNING "Micro-assembler field overflow\n");
165
166	WARN(arg & 0x3, KERN_WARNING "Invalid micro-assembler branch target\n");
167
168	return ((arg < 0) ? (1 << 15) : 0) | ((arg >> 2) & 0x7fff);
169}
170
171static inline u32 build_jimm(u32 arg)
172{
173	WARN(arg & ~(JIMM_MASK << 2),
174	     KERN_WARNING "Micro-assembler field overflow\n");
175
176	return (arg >> 2) & JIMM_MASK;
177}
178
179/*
180 * The order of opcode arguments is implicitly left to right,
181 * starting with RS and ending with FUNC or IMM.
182 */
183static void build_insn(u32 **buf, enum opcode opc, ...)
184{
185	struct insn *ip = NULL;
186	unsigned int i;
187	va_list ap;
188	u32 op;
189
190	for (i = 0; insn_table[i].opcode != insn_invalid; i++)
191		if (insn_table[i].opcode == opc) {
192			ip = &insn_table[i];
193			break;
194		}
195
196	if (!ip || (opc == insn_daddiu && r4k_daddiu_bug()))
197		panic("Unsupported Micro-assembler instruction %d", opc);
198
199	op = ip->match;
200	va_start(ap, opc);
201	if (ip->fields & RS)
202		op |= build_rs(va_arg(ap, u32));
203	if (ip->fields & RT)
204		op |= build_rt(va_arg(ap, u32));
205	if (ip->fields & RD)
206		op |= build_rd(va_arg(ap, u32));
207	if (ip->fields & RE)
208		op |= build_re(va_arg(ap, u32));
209	if (ip->fields & SIMM)
210		op |= build_simm(va_arg(ap, s32));
211	if (ip->fields & UIMM)
212		op |= build_uimm(va_arg(ap, u32));
213	if (ip->fields & BIMM)
214		op |= build_bimm(va_arg(ap, s32));
215	if (ip->fields & JIMM)
216		op |= build_jimm(va_arg(ap, u32));
217	if (ip->fields & FUNC)
218		op |= build_func(va_arg(ap, u32));
219	if (ip->fields & SET)
220		op |= build_set(va_arg(ap, u32));
221	if (ip->fields & SCIMM)
222		op |= build_scimm(va_arg(ap, u32));
223	if (ip->fields & SIMM9)
224		op |= build_scimm9(va_arg(ap, u32));
225	va_end(ap);
226
227	**buf = op;
228	(*buf)++;
229}
230
231static inline void
232__resolve_relocs(struct uasm_reloc *rel, struct uasm_label *lab)
233{
234	long laddr = (long)lab->addr;
235	long raddr = (long)rel->addr;
236
237	switch (rel->type) {
238	case R_MIPS_PC16:
239		*rel->addr |= build_bimm(laddr - (raddr + 4));
240		break;
241
242	default:
243		panic("Unsupported Micro-assembler relocation %d",
244		      rel->type);
245	}
246}
247