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 	    swreg_type(lreg) != NN_REG_NONE)
125 		return -EFAULT;
126 
127 	if (swreg_type(lreg) == NN_REG_GPR_B ||
128 	    swreg_type(rreg) == NN_REG_GPR_A) {
129 		reg->areg = nfp_swreg_to_unreg(rreg, false);
130 		reg->breg = nfp_swreg_to_unreg(lreg, false);
131 		reg->swap = true;
132 	} else {
133 		reg->areg = nfp_swreg_to_unreg(lreg, false);
134 		reg->breg = nfp_swreg_to_unreg(rreg, false);
135 	}
136 
137 	reg->dst_lmextn = swreg_lmextn(dst);
138 	reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg);
139 
140 	return 0;
141 }
142 
143 static u16 nfp_swreg_to_rereg(swreg reg, bool is_dst, bool has_imm8, bool *i8)
144 {
145 	u16 val = swreg_value(reg);
146 	bool lm_id;
147 
148 	switch (swreg_type(reg)) {
149 	case NN_REG_GPR_A:
150 	case NN_REG_GPR_B:
151 	case NN_REG_GPR_BOTH:
152 		return val;
153 	case NN_REG_XFER:
154 		return RE_REG_XFR | val;
155 	case NN_REG_LMEM:
156 		lm_id = swreg_lm_idx(reg);
157 
158 		if (swreg_lm_mode(reg) != NN_LM_MOD_NONE) {
159 			pr_err("bad LM mode for restricted operands %d\n",
160 			       swreg_lm_mode(reg));
161 			return 0;
162 		}
163 
164 		if (val & ~RE_REG_LM_IDX_MAX) {
165 			pr_err("LM offset too large\n");
166 			return 0;
167 		}
168 
169 		return RE_REG_LM | FIELD_PREP(RE_REG_LM_IDX, lm_id) | val;
170 	case NN_REG_IMM:
171 		if (val & ~(0x7f | has_imm8 << 7)) {
172 			pr_err("immediate too large\n");
173 			return 0;
174 		}
175 		*i8 = val & 0x80;
176 		return RE_REG_IMM_encode(val & 0x7f);
177 	case NN_REG_NONE:
178 		return is_dst ? RE_REG_NO_DST : REG_NONE;
179 	case NN_REG_NNR:
180 		pr_err("NNRs used with restricted encoding\n");
181 		return 0;
182 	}
183 
184 	pr_err("unrecognized reg encoding\n");
185 	return 0;
186 }
187 
188 int swreg_to_restricted(swreg dst, swreg lreg, swreg rreg,
189 			struct nfp_insn_re_regs *reg, bool has_imm8)
190 {
191 	memset(reg, 0, sizeof(*reg));
192 
193 	/* Decode destination */
194 	if (swreg_type(dst) == NN_REG_IMM)
195 		return -EFAULT;
196 
197 	if (swreg_type(dst) == NN_REG_GPR_B)
198 		reg->dst_ab = ALU_DST_B;
199 	if (swreg_type(dst) == NN_REG_GPR_BOTH)
200 		reg->wr_both = true;
201 	reg->dst = nfp_swreg_to_rereg(dst, true, false, NULL);
202 
203 	/* Decode source operands */
204 	if (swreg_type(lreg) == swreg_type(rreg) &&
205 	    swreg_type(lreg) != NN_REG_NONE)
206 		return -EFAULT;
207 
208 	if (swreg_type(lreg) == NN_REG_GPR_B ||
209 	    swreg_type(rreg) == NN_REG_GPR_A) {
210 		reg->areg = nfp_swreg_to_rereg(rreg, false, has_imm8, &reg->i8);
211 		reg->breg = nfp_swreg_to_rereg(lreg, false, has_imm8, &reg->i8);
212 		reg->swap = true;
213 	} else {
214 		reg->areg = nfp_swreg_to_rereg(lreg, false, has_imm8, &reg->i8);
215 		reg->breg = nfp_swreg_to_rereg(rreg, false, has_imm8, &reg->i8);
216 	}
217 
218 	reg->dst_lmextn = swreg_lmextn(dst);
219 	reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg);
220 
221 	return 0;
222 }
223 
224 #define NFP_USTORE_ECC_POLY_WORDS		7
225 #define NFP_USTORE_OP_BITS			45
226 
227 static const u64 nfp_ustore_ecc_polynomials[NFP_USTORE_ECC_POLY_WORDS] = {
228 	0x0ff800007fffULL,
229 	0x11f801ff801fULL,
230 	0x1e387e0781e1ULL,
231 	0x17cb8e388e22ULL,
232 	0x1af5b2c93244ULL,
233 	0x1f56d5525488ULL,
234 	0x0daf69a46910ULL,
235 };
236 
237 static bool parity(u64 value)
238 {
239 	return hweight64(value) & 1;
240 }
241 
242 int nfp_ustore_check_valid_no_ecc(u64 insn)
243 {
244 	if (insn & ~GENMASK_ULL(NFP_USTORE_OP_BITS, 0))
245 		return -EINVAL;
246 
247 	return 0;
248 }
249 
250 u64 nfp_ustore_calc_ecc_insn(u64 insn)
251 {
252 	u8 ecc = 0;
253 	int i;
254 
255 	for (i = 0; i < NFP_USTORE_ECC_POLY_WORDS; i++)
256 		ecc |= parity(nfp_ustore_ecc_polynomials[i] & insn) << i;
257 
258 	return insn | (u64)ecc << NFP_USTORE_OP_BITS;
259 }
260