xref: /openbmc/u-boot/drivers/crypto/ace_sha.c (revision b46694df)
1 /*
2  * Advanced Crypto Engine - SHA Firmware
3  * Copyright (c) 2012  Samsung Electronics
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  *
19  */
20 #include <common.h>
21 #include <sha256.h>
22 #include <sha1.h>
23 #include <asm/errno.h>
24 #include "ace_sha.h"
25 
26 /* SHA1 value for the message of zero length */
27 static const unsigned char sha1_digest_emptymsg[SHA1_SUM_LEN] = {
28 	0xDA, 0x39, 0xA3, 0xEE, 0x5E, 0x6B, 0x4B, 0x0D,
29 	0x32, 0x55, 0xBF, 0xFF, 0x95, 0x60, 0x18, 0x90,
30 	0xAF, 0xD8, 0x07, 0x09};
31 
32 /* SHA256 value for the message of zero length */
33 static const unsigned char sha256_digest_emptymsg[SHA256_SUM_LEN] = {
34 	0xE3, 0xB0, 0xC4, 0x42, 0x98, 0xFC, 0x1C, 0x14,
35 	0x9A, 0xFB, 0xF4, 0xC8, 0x99, 0x6F, 0xB9, 0x24,
36 	0x27, 0xAE, 0x41, 0xE4, 0x64, 0x9B, 0x93, 0x4C,
37 	0xA4, 0x95, 0x99, 0x1B, 0x78, 0x52, 0xB8, 0x55};
38 
39 int ace_sha_hash_digest(const unsigned char *pbuf, unsigned int buf_len,
40 			unsigned char *pout, unsigned int hash_type)
41 {
42 	unsigned int i, reg, len;
43 	unsigned int *pdigest;
44 	struct exynos_ace_sfr *ace_sha_reg =
45 		(struct exynos_ace_sfr *)samsung_get_base_ace_sfr();
46 
47 	if (buf_len == 0) {
48 		/* ACE H/W cannot compute hash value for empty string */
49 		if (hash_type == ACE_SHA_TYPE_SHA1)
50 			memcpy(pout, sha1_digest_emptymsg, SHA1_SUM_LEN);
51 		else
52 			memcpy(pout, sha256_digest_emptymsg, SHA256_SUM_LEN);
53 		return 0;
54 	}
55 
56 	/* Flush HRDMA */
57 	writel(ACE_FC_HRDMACFLUSH_ON, &ace_sha_reg->fc_hrdmac);
58 	writel(ACE_FC_HRDMACFLUSH_OFF, &ace_sha_reg->fc_hrdmac);
59 
60 	/* Set byte swap of data in */
61 	writel(ACE_HASH_SWAPDI_ON | ACE_HASH_SWAPDO_ON | ACE_HASH_SWAPIV_ON,
62 	       &ace_sha_reg->hash_byteswap);
63 
64 	/* Select Hash input mux as external source */
65 	reg = readl(&ace_sha_reg->fc_fifoctrl);
66 	reg = (reg & ~ACE_FC_SELHASH_MASK) | ACE_FC_SELHASH_EXOUT;
67 	writel(reg, &ace_sha_reg->fc_fifoctrl);
68 
69 	/* Set Hash as SHA1 or SHA256 and start Hash engine */
70 	reg = (hash_type == ACE_SHA_TYPE_SHA1) ?
71 		ACE_HASH_ENGSEL_SHA1HASH : ACE_HASH_ENGSEL_SHA256HASH;
72 	reg |= ACE_HASH_STARTBIT_ON;
73 	writel(reg, &ace_sha_reg->hash_control);
74 
75 	/* Enable FIFO mode */
76 	writel(ACE_HASH_FIFO_ON, &ace_sha_reg->hash_fifo_mode);
77 
78 	/* Set message length */
79 	writel(buf_len, &ace_sha_reg->hash_msgsize_low);
80 	writel(0, &ace_sha_reg->hash_msgsize_high);
81 
82 	/* Set HRDMA */
83 	writel((unsigned int)pbuf, &ace_sha_reg->fc_hrdmas);
84 	writel(buf_len, &ace_sha_reg->fc_hrdmal);
85 
86 	while ((readl(&ace_sha_reg->hash_status) & ACE_HASH_MSGDONE_MASK) ==
87 		ACE_HASH_MSGDONE_OFF) {
88 		/*
89 		 * PRNG error bit goes HIGH if a PRNG request occurs without
90 		 * a complete seed setup. We are using this bit to check h/w
91 		 * fault because proper setup is not expected in that case.
92 		 */
93 		if ((readl(&ace_sha_reg->hash_status)
94 			& ACE_HASH_PRNGERROR_MASK) == ACE_HASH_PRNGERROR_ON)
95 			return -EBUSY;
96 	}
97 
98 	/* Clear MSG_DONE bit */
99 	writel(ACE_HASH_MSGDONE_ON, &ace_sha_reg->hash_status);
100 
101 	/* Read hash result */
102 	pdigest = (unsigned int *)pout;
103 	len = (hash_type == ACE_SHA_TYPE_SHA1) ? SHA1_SUM_LEN : SHA256_SUM_LEN;
104 
105 	for (i = 0; i < len / 4; i++)
106 		pdigest[i] = readl(&ace_sha_reg->hash_result[i]);
107 
108 	/* Clear HRDMA pending bit */
109 	writel(ACE_FC_HRDMA, &ace_sha_reg->fc_intpend);
110 
111 	return 0;
112 }
113 
114 void hw_sha256(const unsigned char *pbuf, unsigned int buf_len,
115 			unsigned char *pout, unsigned int chunk_size)
116 {
117 	if (ace_sha_hash_digest(pbuf, buf_len, pout, ACE_SHA_TYPE_SHA256))
118 		debug("ACE was not setup properly or it is faulty\n");
119 }
120 
121 void hw_sha1(const unsigned char *pbuf, unsigned int buf_len,
122 			unsigned char *pout, unsigned int chunk_size)
123 {
124 	if (ace_sha_hash_digest(pbuf, buf_len, pout, ACE_SHA_TYPE_SHA1))
125 		debug("ACE was not setup properly or it is faulty\n");
126 }
127