xref: /openbmc/u-boot/drivers/crypto/ace_sha.c (revision c2cde27d)
1 /*
2  * Advanced Crypto Engine - SHA Firmware
3  * Copyright (c) 2012  Samsung Electronics
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 #include <common.h>
8 #include <sha256.h>
9 #include <sha1.h>
10 #include <asm/errno.h>
11 #include "ace_sha.h"
12 
13 /* SHA1 value for the message of zero length */
14 static const unsigned char sha1_digest_emptymsg[SHA1_SUM_LEN] = {
15 	0xDA, 0x39, 0xA3, 0xEE, 0x5E, 0x6B, 0x4B, 0x0D,
16 	0x32, 0x55, 0xBF, 0xFF, 0x95, 0x60, 0x18, 0x90,
17 	0xAF, 0xD8, 0x07, 0x09};
18 
19 /* SHA256 value for the message of zero length */
20 static const unsigned char sha256_digest_emptymsg[SHA256_SUM_LEN] = {
21 	0xE3, 0xB0, 0xC4, 0x42, 0x98, 0xFC, 0x1C, 0x14,
22 	0x9A, 0xFB, 0xF4, 0xC8, 0x99, 0x6F, 0xB9, 0x24,
23 	0x27, 0xAE, 0x41, 0xE4, 0x64, 0x9B, 0x93, 0x4C,
24 	0xA4, 0x95, 0x99, 0x1B, 0x78, 0x52, 0xB8, 0x55};
25 
26 int ace_sha_hash_digest(const unsigned char *pbuf, unsigned int buf_len,
27 			unsigned char *pout, unsigned int hash_type)
28 {
29 	unsigned int i, reg, len;
30 	unsigned int *pdigest;
31 	struct exynos_ace_sfr *ace_sha_reg =
32 		(struct exynos_ace_sfr *)samsung_get_base_ace_sfr();
33 
34 	if (buf_len == 0) {
35 		/* ACE H/W cannot compute hash value for empty string */
36 		if (hash_type == ACE_SHA_TYPE_SHA1)
37 			memcpy(pout, sha1_digest_emptymsg, SHA1_SUM_LEN);
38 		else
39 			memcpy(pout, sha256_digest_emptymsg, SHA256_SUM_LEN);
40 		return 0;
41 	}
42 
43 	/* Flush HRDMA */
44 	writel(ACE_FC_HRDMACFLUSH_ON, &ace_sha_reg->fc_hrdmac);
45 	writel(ACE_FC_HRDMACFLUSH_OFF, &ace_sha_reg->fc_hrdmac);
46 
47 	/* Set byte swap of data in */
48 	writel(ACE_HASH_SWAPDI_ON | ACE_HASH_SWAPDO_ON | ACE_HASH_SWAPIV_ON,
49 	       &ace_sha_reg->hash_byteswap);
50 
51 	/* Select Hash input mux as external source */
52 	reg = readl(&ace_sha_reg->fc_fifoctrl);
53 	reg = (reg & ~ACE_FC_SELHASH_MASK) | ACE_FC_SELHASH_EXOUT;
54 	writel(reg, &ace_sha_reg->fc_fifoctrl);
55 
56 	/* Set Hash as SHA1 or SHA256 and start Hash engine */
57 	reg = (hash_type == ACE_SHA_TYPE_SHA1) ?
58 		ACE_HASH_ENGSEL_SHA1HASH : ACE_HASH_ENGSEL_SHA256HASH;
59 	reg |= ACE_HASH_STARTBIT_ON;
60 	writel(reg, &ace_sha_reg->hash_control);
61 
62 	/* Enable FIFO mode */
63 	writel(ACE_HASH_FIFO_ON, &ace_sha_reg->hash_fifo_mode);
64 
65 	/* Set message length */
66 	writel(buf_len, &ace_sha_reg->hash_msgsize_low);
67 	writel(0, &ace_sha_reg->hash_msgsize_high);
68 
69 	/* Set HRDMA */
70 	writel((unsigned int)pbuf, &ace_sha_reg->fc_hrdmas);
71 	writel(buf_len, &ace_sha_reg->fc_hrdmal);
72 
73 	while ((readl(&ace_sha_reg->hash_status) & ACE_HASH_MSGDONE_MASK) ==
74 		ACE_HASH_MSGDONE_OFF) {
75 		/*
76 		 * PRNG error bit goes HIGH if a PRNG request occurs without
77 		 * a complete seed setup. We are using this bit to check h/w
78 		 * fault because proper setup is not expected in that case.
79 		 */
80 		if ((readl(&ace_sha_reg->hash_status)
81 			& ACE_HASH_PRNGERROR_MASK) == ACE_HASH_PRNGERROR_ON)
82 			return -EBUSY;
83 	}
84 
85 	/* Clear MSG_DONE bit */
86 	writel(ACE_HASH_MSGDONE_ON, &ace_sha_reg->hash_status);
87 
88 	/* Read hash result */
89 	pdigest = (unsigned int *)pout;
90 	len = (hash_type == ACE_SHA_TYPE_SHA1) ? SHA1_SUM_LEN : SHA256_SUM_LEN;
91 
92 	for (i = 0; i < len / 4; i++)
93 		pdigest[i] = readl(&ace_sha_reg->hash_result[i]);
94 
95 	/* Clear HRDMA pending bit */
96 	writel(ACE_FC_HRDMA, &ace_sha_reg->fc_intpend);
97 
98 	return 0;
99 }
100 
101 void hw_sha256(const unsigned char *pbuf, unsigned int buf_len,
102 			unsigned char *pout, unsigned int chunk_size)
103 {
104 	if (ace_sha_hash_digest(pbuf, buf_len, pout, ACE_SHA_TYPE_SHA256))
105 		debug("ACE was not setup properly or it is faulty\n");
106 }
107 
108 void hw_sha1(const unsigned char *pbuf, unsigned int buf_len,
109 			unsigned char *pout, unsigned int chunk_size)
110 {
111 	if (ace_sha_hash_digest(pbuf, buf_len, pout, ACE_SHA_TYPE_SHA1))
112 		debug("ACE was not setup properly or it is faulty\n");
113 }
114