manager: Save and Restore BIOS Attributes
This commit saves any updates made to BIOS attributes
to VPD.
It also restores the attributes from the VPD when we
start VPD manager.
Signed-off-by: Santosh Puranik <santosh.puranik@in.ibm.com>
Change-Id: Idb28e2f89d21ccd89eb8e56490eb7f31397ff5f5
diff --git a/vpd-manager/bios_handler.hpp b/vpd-manager/bios_handler.hpp
new file mode 100644
index 0000000..ad6f05e
--- /dev/null
+++ b/vpd-manager/bios_handler.hpp
@@ -0,0 +1,169 @@
+#pragma once
+
+#include "types.hpp"
+
+#include <stdint.h>
+
+#include <string>
+
+namespace sdbusplus
+{
+namespace bus
+{
+class bus;
+} // namespace bus
+} // namespace sdbusplus
+
+namespace sdbusplus
+{
+namespace message
+{
+class message;
+} // namespace message
+} // namespace sdbusplus
+
+namespace openpower
+{
+namespace vpd
+{
+namespace manager
+{
+
+class Manager;
+/**
+ * @brief A class that handles changes to BIOS attributes backed by VPD.
+ *
+ * This class has APIs that handle updates to BIOS attributes that need to
+ * be backed up to VPD. It mainly does the following:
+ * 1) Checks if the VPD keywords that BIOS attributes are backed to are
+ * uninitialized. If so, it initializes them.
+ * 2) Listens for changes to BIOS attributes and synchronizes them to the
+ * appropriate VPD keyword.
+ *
+ * Since on a factory reset like scenario, the BIOS attributes are initialized
+ * by PLDM, this code waits until PLDM has grabbed a bus name before attempting
+ * any syncs.
+ */
+class BiosHandler
+{
+ public:
+ // Some default and deleted constructors and assignments.
+ BiosHandler() = delete;
+ BiosHandler(const BiosHandler&) = delete;
+ BiosHandler& operator=(const BiosHandler&) = delete;
+ BiosHandler(Manager&&) = delete;
+ BiosHandler& operator=(BiosHandler&&) = delete;
+ ~BiosHandler() = default;
+
+ BiosHandler(sdbusplus::bus::bus& bus, Manager& manager) :
+ bus(bus), manager(manager)
+ {
+ checkAndListenPLDMService();
+ }
+
+ private:
+ /**
+ * @brief Check if PLDM service is running and run BIOS sync
+ *
+ * This API checks if the PLDM service is running and if yes it will start
+ * an immediate sync of BIOS attributes. If the service is not running, it
+ * registers a listener to be notified when the service starts so that a
+ * restore can be performed.
+ */
+ void checkAndListenPLDMService();
+
+ /**
+ * @brief Register listener for changes to BIOS Attributes.
+ *
+ * The VPD manager needs to listen to changes to certain BIOS attributes
+ * that are backed by VPD. When the attributes we are interested in
+ * change, the VPD manager will make sure that we write them back to the
+ * VPD keywords that back them up.
+ */
+ void listenBiosAttribs();
+
+ /**
+ * @brief Callback for BIOS Attribute changes
+ *
+ * Checks if the BIOS attribute(s) changed are those backed up by VPD. If
+ * yes, it will update the VPD with the new attribute value.
+ * @param[in] msg - The callback message.
+ */
+ void biosAttribsCallback(sdbusplus::message::message& msg);
+
+ /**
+ * @brief Persistently saves the Memory mirror mode
+ *
+ * Memory mirror mode setting is saved to the UTIL/D0 keyword in the
+ * motherboard VPD. If the mirror mode in BIOS is "Disabled", set D0 to 1,
+ * if "Enabled" set D0 to 2
+ *
+ * @param[in] mirrorMode - The mirror mode BIOS attribute.
+ */
+ void saveAMMToVPD(const std::string& mirrorMode);
+
+ /**
+ * @brief Persistently saves the Field Core Override setting
+ *
+ * Saves the field core override value (FCO) into the VSYS/RG keyword in
+ * the motherboard VPD.
+ *
+ * @param[in] fcoVal - The FCO value as an integer.
+ */
+ void saveFCOToVPD(int64_t fcoVal);
+
+ /**
+ * @brief Writes Memory mirror mode to BIOS
+ *
+ * Writes to the hb_memory_mirror_mode BIOS attribute.
+ *
+ * @param[in] ammVal - The mirror mode as read from VPD.
+ */
+ void saveAMMToBIOS(const std::string& ammVal);
+
+ /**
+ * @brief Writes Field Core Override to BIOS
+ *
+ * Writes to the hb_field_core_override BIOS attribute.
+ *
+ * @param[in] fcoVal - The FCO value as read from VPD.
+ */
+ void saveFCOToBIOS(const std::string& fcoVal);
+
+ /**
+ * @brief Reads the hb_memory_mirror_mode attribute
+ *
+ * @return int64_t - The AMM BIOS attribute. -1 on failure.
+ */
+ std::string readBIOSAMM();
+
+ /**
+ * @brief Reads the hb_field_core_override attribute
+ *
+ * @return std::string - The FCO BIOS attribute. Empty string on failure.
+ */
+ int64_t readBIOSFCO();
+
+ /**
+ * @brief Restore BIOS attributes
+ *
+ * This function checks if we are coming out of a factory reset. If yes,
+ * it checks the VPD cache for valid backed up copy of the FCO and AMM
+ * BIOS attributes. If valid values are found in the VPD, it will apply
+ * those to the BIOS attributes.
+ */
+ void restoreBIOSAttribs();
+
+ /**
+ * @brief Reference to the bus.
+ */
+ sdbusplus::bus::bus& bus;
+
+ /**
+ * @brief Reference to the manager.
+ */
+ Manager& manager;
+}; // class BiosHandler
+} // namespace manager
+} // namespace vpd
+} // namespace openpower
\ No newline at end of file