1 /*
2  * Copyright (C) 2016-2017 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include <linux/bitops.h>
35 #include <linux/errno.h>
36 #include <linux/kernel.h>
37 #include <linux/string.h>
38 #include <linux/types.h>
39 
40 #include "nfp_asm.h"
41 
42 const struct cmd_tgt_act cmd_tgt_act[__CMD_TGT_MAP_SIZE] = {
43 	[CMD_TGT_WRITE8_SWAP] =		{ 0x02, 0x42 },
44 	[CMD_TGT_READ8] =		{ 0x01, 0x43 },
45 	[CMD_TGT_READ32] =		{ 0x00, 0x5c },
46 	[CMD_TGT_READ32_LE] =		{ 0x01, 0x5c },
47 	[CMD_TGT_READ32_SWAP] =		{ 0x02, 0x5c },
48 	[CMD_TGT_READ_LE] =		{ 0x01, 0x40 },
49 	[CMD_TGT_READ_SWAP_LE] =	{ 0x03, 0x40 },
50 };
51 
52 static u16 nfp_swreg_to_unreg(swreg reg, bool is_dst)
53 {
54 	bool lm_id, lm_dec = false;
55 	u16 val = swreg_value(reg);
56 
57 	switch (swreg_type(reg)) {
58 	case NN_REG_GPR_A:
59 	case NN_REG_GPR_B:
60 	case NN_REG_GPR_BOTH:
61 		return val;
62 	case NN_REG_NNR:
63 		return UR_REG_NN | val;
64 	case NN_REG_XFER:
65 		return UR_REG_XFR | val;
66 	case NN_REG_LMEM:
67 		lm_id = swreg_lm_idx(reg);
68 
69 		switch (swreg_lm_mode(reg)) {
70 		case NN_LM_MOD_NONE:
71 			if (val & ~UR_REG_LM_IDX_MAX) {
72 				pr_err("LM offset too large\n");
73 				return 0;
74 			}
75 			return UR_REG_LM | FIELD_PREP(UR_REG_LM_IDX, lm_id) |
76 				val;
77 		case NN_LM_MOD_DEC:
78 			lm_dec = true;
79 			/* fall through */
80 		case NN_LM_MOD_INC:
81 			if (val) {
82 				pr_err("LM offset in inc/dev mode\n");
83 				return 0;
84 			}
85 			return UR_REG_LM | UR_REG_LM_POST_MOD |
86 				FIELD_PREP(UR_REG_LM_IDX, lm_id) |
87 				FIELD_PREP(UR_REG_LM_POST_MOD_DEC, lm_dec);
88 		default:
89 			pr_err("bad LM mode for unrestricted operands %d\n",
90 			       swreg_lm_mode(reg));
91 			return 0;
92 		}
93 	case NN_REG_IMM:
94 		if (val & ~0xff) {
95 			pr_err("immediate too large\n");
96 			return 0;
97 		}
98 		return UR_REG_IMM_encode(val);
99 	case NN_REG_NONE:
100 		return is_dst ? UR_REG_NO_DST : REG_NONE;
101 	}
102 
103 	pr_err("unrecognized reg encoding %08x\n", reg);
104 	return 0;
105 }
106 
107 int swreg_to_unrestricted(swreg dst, swreg lreg, swreg rreg,
108 			  struct nfp_insn_ur_regs *reg)
109 {
110 	memset(reg, 0, sizeof(*reg));
111 
112 	/* Decode destination */
113 	if (swreg_type(dst) == NN_REG_IMM)
114 		return -EFAULT;
115 
116 	if (swreg_type(dst) == NN_REG_GPR_B)
117 		reg->dst_ab = ALU_DST_B;
118 	if (swreg_type(dst) == NN_REG_GPR_BOTH)
119 		reg->wr_both = true;
120 	reg->dst = nfp_swreg_to_unreg(dst, true);
121 
122 	/* Decode source operands */
123 	if (swreg_type(lreg) == swreg_type(rreg))
124 		return -EFAULT;
125 
126 	if (swreg_type(lreg) == NN_REG_GPR_B ||
127 	    swreg_type(rreg) == NN_REG_GPR_A) {
128 		reg->areg = nfp_swreg_to_unreg(rreg, false);
129 		reg->breg = nfp_swreg_to_unreg(lreg, false);
130 		reg->swap = true;
131 	} else {
132 		reg->areg = nfp_swreg_to_unreg(lreg, false);
133 		reg->breg = nfp_swreg_to_unreg(rreg, false);
134 	}
135 
136 	reg->dst_lmextn = swreg_lmextn(dst);
137 	reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg);
138 
139 	return 0;
140 }
141 
142 static u16 nfp_swreg_to_rereg(swreg reg, bool is_dst, bool has_imm8, bool *i8)
143 {
144 	u16 val = swreg_value(reg);
145 	bool lm_id;
146 
147 	switch (swreg_type(reg)) {
148 	case NN_REG_GPR_A:
149 	case NN_REG_GPR_B:
150 	case NN_REG_GPR_BOTH:
151 		return val;
152 	case NN_REG_XFER:
153 		return RE_REG_XFR | val;
154 	case NN_REG_LMEM:
155 		lm_id = swreg_lm_idx(reg);
156 
157 		if (swreg_lm_mode(reg) != NN_LM_MOD_NONE) {
158 			pr_err("bad LM mode for restricted operands %d\n",
159 			       swreg_lm_mode(reg));
160 			return 0;
161 		}
162 
163 		if (val & ~RE_REG_LM_IDX_MAX) {
164 			pr_err("LM offset too large\n");
165 			return 0;
166 		}
167 
168 		return RE_REG_LM | FIELD_PREP(RE_REG_LM_IDX, lm_id) | val;
169 	case NN_REG_IMM:
170 		if (val & ~(0x7f | has_imm8 << 7)) {
171 			pr_err("immediate too large\n");
172 			return 0;
173 		}
174 		*i8 = val & 0x80;
175 		return RE_REG_IMM_encode(val & 0x7f);
176 	case NN_REG_NONE:
177 		return is_dst ? RE_REG_NO_DST : REG_NONE;
178 	case NN_REG_NNR:
179 		pr_err("NNRs used with restricted encoding\n");
180 		return 0;
181 	}
182 
183 	pr_err("unrecognized reg encoding\n");
184 	return 0;
185 }
186 
187 int swreg_to_restricted(swreg dst, swreg lreg, swreg rreg,
188 			struct nfp_insn_re_regs *reg, bool has_imm8)
189 {
190 	memset(reg, 0, sizeof(*reg));
191 
192 	/* Decode destination */
193 	if (swreg_type(dst) == NN_REG_IMM)
194 		return -EFAULT;
195 
196 	if (swreg_type(dst) == NN_REG_GPR_B)
197 		reg->dst_ab = ALU_DST_B;
198 	if (swreg_type(dst) == NN_REG_GPR_BOTH)
199 		reg->wr_both = true;
200 	reg->dst = nfp_swreg_to_rereg(dst, true, false, NULL);
201 
202 	/* Decode source operands */
203 	if (swreg_type(lreg) == swreg_type(rreg))
204 		return -EFAULT;
205 
206 	if (swreg_type(lreg) == NN_REG_GPR_B ||
207 	    swreg_type(rreg) == NN_REG_GPR_A) {
208 		reg->areg = nfp_swreg_to_rereg(rreg, false, has_imm8, &reg->i8);
209 		reg->breg = nfp_swreg_to_rereg(lreg, false, has_imm8, &reg->i8);
210 		reg->swap = true;
211 	} else {
212 		reg->areg = nfp_swreg_to_rereg(lreg, false, has_imm8, &reg->i8);
213 		reg->breg = nfp_swreg_to_rereg(rreg, false, has_imm8, &reg->i8);
214 	}
215 
216 	reg->dst_lmextn = swreg_lmextn(dst);
217 	reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg);
218 
219 	return 0;
220 }
221 
222 #define NFP_USTORE_ECC_POLY_WORDS		7
223 #define NFP_USTORE_OP_BITS			45
224 
225 static const u64 nfp_ustore_ecc_polynomials[NFP_USTORE_ECC_POLY_WORDS] = {
226 	0x0ff800007fffULL,
227 	0x11f801ff801fULL,
228 	0x1e387e0781e1ULL,
229 	0x17cb8e388e22ULL,
230 	0x1af5b2c93244ULL,
231 	0x1f56d5525488ULL,
232 	0x0daf69a46910ULL,
233 };
234 
235 static bool parity(u64 value)
236 {
237 	return hweight64(value) & 1;
238 }
239 
240 int nfp_ustore_check_valid_no_ecc(u64 insn)
241 {
242 	if (insn & ~GENMASK_ULL(NFP_USTORE_OP_BITS, 0))
243 		return -EINVAL;
244 
245 	return 0;
246 }
247 
248 u64 nfp_ustore_calc_ecc_insn(u64 insn)
249 {
250 	u8 ecc = 0;
251 	int i;
252 
253 	for (i = 0; i < NFP_USTORE_ECC_POLY_WORDS; i++)
254 		ecc |= parity(nfp_ustore_ecc_polynomials[i] & insn) << i;
255 
256 	return insn | (u64)ecc << NFP_USTORE_OP_BITS;
257 }
258