1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stdbool.h>
18 #include <stdint.h>
19 #include <string.h>
20
21 #include <bl.h>
22 #include <eeData.h>
23
24 extern uint32_t __eedata_start[], __eedata_end[];
25
26 //STM32F4xx eedata stores data in 4-byte aligned chunks
27
eeFind(uint32_t nameToFind,uint32_t * offset,bool findFirst,uint32_t * szP)28 static void* eeFind(uint32_t nameToFind, uint32_t *offset, bool findFirst, uint32_t *szP)
29 {
30 uint32_t *p = __eedata_start + (offset ? *offset : 0);
31 void *foundData = NULL;
32
33 //find the last incarnation of "name" in flash area
34 while (p < __eedata_end) {
35 uint32_t info = *p++;
36 uint32_t name = info & EE_DATA_NAME_MAX;
37 uint32_t sz = info / (EE_DATA_NAME_MAX + 1);
38 void *data = p;
39
40 //skip over to next data chunk header
41 p += (sz + 3) / 4;
42
43 //check for a match
44 if (nameToFind == name) {
45 *szP = sz;
46 foundData = data;
47
48 if (findFirst)
49 break;
50 }
51
52 //check for ending condition (name == max)
53 if (name == EE_DATA_NAME_MAX)
54 break;
55 }
56
57 if (offset)
58 *offset = p - __eedata_start;
59
60 return foundData;
61 }
62
eeIsValidName(uint32_t name)63 static bool eeIsValidName(uint32_t name)
64 {
65 return name && name < EE_DATA_NAME_MAX;
66 }
67
eeDataGetEx(uint32_t name,uint32_t * offsetP,bool first,void * buf,uint32_t * szP)68 static void *eeDataGetEx(uint32_t name, uint32_t *offsetP, bool first, void *buf, uint32_t *szP)
69 {
70 uint32_t sz = 0;
71 void *data;
72
73 if (!eeIsValidName(name))
74 return false;
75
76 //find the data item
77 data = eeFind(name, offsetP, first, &sz);
78 if (!data)
79 return NULL;
80
81 if (buf && szP) { //get the data
82 if (sz > *szP)
83 sz = *szP;
84 *szP = sz;
85 memcpy(buf, data, sz);
86 }
87 else if (szP) //get size
88 *szP = sz;
89
90 return (uint32_t*)data - 1;
91 }
92
eeDataGet(uint32_t name,void * buf,uint32_t * szP)93 bool eeDataGet(uint32_t name, void *buf, uint32_t *szP)
94 {
95 uint32_t offset = 0;
96
97 return eeDataGetEx(name, &offset, false, buf, szP) != NULL;
98 }
99
eeDataGetAllVersions(uint32_t name,void * buf,uint32_t * szP,void ** stateP)100 void *eeDataGetAllVersions(uint32_t name, void *buf, uint32_t *szP, void **stateP)
101 {
102 uint32_t offset = *(uint32_t*)stateP;
103 void *addr = eeDataGetEx(name, &offset, true, buf, szP);
104 *(uint32_t*)stateP = offset;
105 return addr;
106 }
107
eeWrite(void * dst,const void * src,uint32_t len)108 static bool eeWrite(void *dst, const void *src, uint32_t len)
109 {
110 return BL.blProgramEe(dst, src, len, BL_FLASH_KEY1, BL_FLASH_KEY2);
111 }
112
eeDataSet(uint32_t name,const void * buf,uint32_t len)113 bool eeDataSet(uint32_t name, const void *buf, uint32_t len)
114 {
115 uint32_t sz, effectiveSz, info = name + len * (EE_DATA_NAME_MAX + 1);
116 bool ret = true;
117 void *space;
118
119 if (!eeIsValidName(name))
120 return false;
121
122 //find the empty space at the end of everything and make sure it is really empty (size == EE_DATA_LEN_MAX)
123 space = eeFind(EE_DATA_NAME_MAX, NULL, false, &sz);
124 if (!space || sz != EE_DATA_LEN_MAX)
125 return false;
126
127 //calculate effective size
128 effectiveSz = (len + 3) &~ 3;
129
130 //verify we have the space
131 if ((uint8_t*)__eedata_end - (uint8_t*)space < effectiveSz)
132 return false;
133
134 //write it in
135 ret = eeWrite(((uint32_t*)space) - 1, &info, sizeof(info)) && ret;
136 ret = eeWrite(space, buf, len) && ret;
137
138 return ret;
139 }
140
eeDataEraseOldVersion(uint32_t name,void * vaddr)141 bool eeDataEraseOldVersion(uint32_t name, void *vaddr)
142 {
143 uint32_t *addr = (uint32_t*)vaddr;
144 uint32_t v;
145
146 // sanity check
147 if (!eeIsValidName(name) || addr < __eedata_start || addr >= (__eedata_end - 1))
148 return false;
149
150 v = *addr;
151
152 //verify name
153 if ((v & EE_DATA_NAME_MAX) != name)
154 return false;
155
156 //clear name
157 v &=~ EE_DATA_NAME_MAX;
158
159 //store result
160 return eeWrite(addr, &v, sizeof(v));
161 }
162