pcie_bifurcation: Fetch bifurcation at a PCIe slot with hardcoded values
This will read a json config and return the bifurcation based on that.
It will read the configure file in a persistent file to see if it is
valid machine config and return the bifurcation information
accordingly.
For example,
If it is valid config, it will return 8x8 for PE1,3,4,6.
Tested:
Unit tests passed.
Physical Tests.
PE0 -> no bifurcation
PE1 -> x8x8
```
$ ipmitool raw 0x2e 0x32 0x79 0x2b 0x00 0x0f 0
79 2b 00 0b 00
$ ipmitool raw 0x2e 0x32 0x79 0x2b 0x00 0x0f 1
79 2b 00 0b 02 08 08
```
Change-Id: I44aefbfb26372f8bc0069343c8a6d07d3cf6f42d
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/bifurcation/bifurcation.hpp b/bifurcation/bifurcation.hpp
new file mode 100644
index 0000000..c0bd23d
--- /dev/null
+++ b/bifurcation/bifurcation.hpp
@@ -0,0 +1,67 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#pragma once
+
+#include <cstdint>
+#include <functional>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <unordered_map>
+#include <vector>
+
+namespace google
+{
+namespace ipmi
+{
+
+class BifurcationInterface
+{
+ public:
+ virtual ~BifurcationInterface() = default;
+
+ /**
+ * Get the Bifurcation of the device at the i2c bus
+ *
+ * @param[in] bus - I2C bus of the device
+ * @return the bifurcation at the i2c bus
+ */
+ virtual std::optional<std::vector<uint8_t>>
+ getBifurcation(uint8_t bus) noexcept = 0;
+};
+
+class BifurcationStatic : public BifurcationInterface
+{
+ public:
+ static std::reference_wrapper<BifurcationInterface> createBifurcation()
+ {
+ static BifurcationStatic bifurcationStatic;
+
+ return std::ref(bifurcationStatic);
+ }
+
+ BifurcationStatic(std::string_view bifurcationFile);
+
+ std::optional<std::vector<uint8_t>>
+ getBifurcation(uint8_t index) noexcept override;
+
+ protected:
+ BifurcationStatic();
+
+ private:
+ std::string bifurcationFile;
+};
+
+} // namespace ipmi
+} // namespace google