1 /*
2  * Copyright 2018 Google Inc.
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 "lpc_aspeed.hpp"
18 
19 #include "mapper_errors.hpp"
20 #include "window_hw_interface.hpp"
21 
22 #include <fcntl.h>
23 #include <linux/aspeed-lpc-ctrl.h>
24 #include <linux/kernel.h>
25 
26 #include <cerrno>
27 #include <cstdint>
28 #include <cstring>
29 #include <memory>
30 #include <string>
31 #include <utility>
32 
33 namespace ipmi_flash
34 {
35 
36 const std::string LpcMapperAspeed::lpcControlPath = "/dev/aspeed-lpc-ctrl";
37 
38 std::unique_ptr<HardwareMapperInterface>
createAspeedMapper(std::uint32_t regionAddress,std::size_t regionSize)39     LpcMapperAspeed::createAspeedMapper(std::uint32_t regionAddress,
40                                         std::size_t regionSize)
41 {
42     /* NOTE: considered using a joint factory to create one or the other, for
43      * now, separate factories.
44      */
45     return std::make_unique<LpcMapperAspeed>(regionAddress, regionSize);
46 }
47 
close()48 void LpcMapperAspeed::close()
49 {
50     if (mappedRegion)
51     {
52         sys->munmap(mappedRegion, regionSize);
53         mappedRegion = nullptr;
54     }
55 
56     if (mappedFd != -1)
57     {
58         sys->close(mappedFd);
59         mappedFd = -1;
60     }
61 }
62 
mapWindow(std::uint32_t address,std::uint32_t length)63 WindowMapResult LpcMapperAspeed::mapWindow(std::uint32_t address,
64                                            std::uint32_t length)
65 {
66     WindowMapResult result = {};
67     static const std::uint32_t MASK_64K = 0xFFFFU;
68     const std::uint32_t offset = address & MASK_64K;
69 
70     if (offset + length > regionSize)
71     {
72         std::fprintf(stderr,
73                      "requested window size %" PRIu32 ", offset %#" PRIx32
74                      " is too large for mem region"
75                      " of size %zu\n",
76                      length, offset, regionSize);
77 
78         result.response = EFBIG;
79         result.windowSize = regionSize - offset;
80         return result;
81     }
82 
83     struct aspeed_lpc_ctrl_mapping map = {
84         .window_type = ASPEED_LPC_CTRL_WINDOW_MEMORY,
85         .window_id = 0,
86         .flags = 0,
87         .addr = address & ~MASK_64K,
88         .offset = 0,
89         .size = __ALIGN_KERNEL_MASK(offset + length, MASK_64K),
90     };
91 
92     std::fprintf(stderr,
93                  "requesting Aspeed LPC window at %#" PRIx32 " of size %" PRIu32
94                  "\n",
95                  map.addr, map.size);
96 
97     const auto lpcControlFd = sys->open(lpcControlPath.c_str(), O_RDWR);
98     if (lpcControlFd == -1)
99     {
100         std::fprintf(stderr,
101                      "cannot open Aspeed LPC kernel control dev \"%s\"\n",
102                      lpcControlPath.c_str());
103 
104         result.response = EINVAL;
105         return result;
106     }
107 
108     if (sys->ioctl(lpcControlFd, ASPEED_LPC_CTRL_IOCTL_MAP, &map) == -1)
109     {
110         std::fprintf(stderr, "Failed to ioctl Aspeed LPC map with error %s\n",
111                      std::strerror(errno));
112         sys->close(lpcControlFd);
113 
114         result.response = EINVAL;
115         return result;
116     }
117 
118     sys->close(lpcControlFd);
119 
120     result.response = 0;
121     result.windowOffset = offset;
122     result.windowSize = length;
123     return result;
124 }
125 
open()126 MemorySet LpcMapperAspeed::open()
127 {
128     if (mapRegion())
129     {
130         MemorySet output;
131         output.mappedFd = mappedFd;
132         output.mapped = mappedRegion;
133         return output;
134     }
135 
136     throw MapperException("Unable to memory-map region");
137 }
138 
mapRegion()139 bool LpcMapperAspeed::mapRegion()
140 {
141     /* Open the file to map. */
142     mappedFd = sys->open(lpcControlPath.c_str(), O_RDONLY | O_SYNC);
143     if (mappedFd == -1)
144     {
145         std::fprintf(stderr, "ipmiflash: unable to open %s\n",
146                      lpcControlPath.c_str());
147         return false;
148     }
149 
150     mappedRegion = reinterpret_cast<uint8_t*>(
151         sys->mmap(0, regionSize, PROT_READ, MAP_SHARED, mappedFd, 0));
152 
153     if (mappedRegion == MAP_FAILED)
154     {
155         sys->close(mappedFd);
156         mappedFd = -1;
157         std::fprintf(stderr, "Mmap failure: '%s'\n", std::strerror(errno));
158         return false;
159     }
160 
161     /* TODO: There is no close() method here, to close mappedFd, or mappedRegion
162      * -- therefore, a good next step will be to evaluate whether or not the
163      * other pieces should go here...
164      */
165     return true;
166 }
167 
168 } // namespace ipmi_flash
169