BloomPatched/src/DebugServers/GdbRsp/AvrGdbRsp/AvrGdbRsp.hpp

#pragma once

#include <cstdint>

#include "src/DebugServers/GdbRsp/GdbRspDebugServer.hpp"
#include "src/DebugServers/GdbRsp/Register.hpp"
#include "src/Helpers/BiMap.hpp"

namespace Bloom::DebugServers::Gdb
{
    /**
     * The AVR GDB client (avr-gdb) defines a set of parameters relating to AVR targets. These parameters are
     * hardcoded in the AVR GDB source code. The client expects all compatible GDB RSP servers to be aware of
     * these parameters.
     *
     * An example of these hardcoded parameters is target registers and the order in which they are supplied; AVR GDB
     * clients expect 35 registers to be accessible via the server. 32 of these registers are general purpose CPU
     * registers. The GP registers are expected to be followed by the status register (SREG), stack pointer
     * register (SPH & SPL) and the program counter. These must all be given in a specific order, which is
     * pre-determined by the AVR GDB client. See AvrGdbRsp::getRegisterNumberToDescriptorMapping() for more.
     *
     * For more on this, see the AVR GDB source code at https://github.com/bminor/binutils-gdb/blob/master/gdb/avr-tdep.c
     *
     * The AvrGdpRsp class extends the generic GDB RSP debug server and implements these AVR specific parameters.
     */
    class AvrGdbRsp: public GdbRspDebugServer
    {
    private:
        /**
         * The mask used by the AVR GDB client to encode the memory type into memory addresses.
         * See AvrGdbRsp::getMemoryTypeFromGdbAddress() for more.
         */
        unsigned int gdbInternalMemoryMask = 0xFE0000u;

    protected:
        /**
         * For AVR targets, avr-gdb defines 35 registers in total:
         *
         * Register number 0 through 31 are general purpose registers
         * Register number 32 is the status register (SREG)
         * Register number 33 is the stack pointer register
         * Register number 34 is the program counter register
         *
         * Only general purpose registers have register IDs. The others do not require an ID.
         *
         * @return
         */
        BiMap<GdbRegisterNumber, Targets::TargetRegisterDescriptor> getRegisterNumberToDescriptorMapping() override {
            using Targets::TargetRegisterDescriptor;
            using Targets::TargetRegisterType;

            static BiMap<GdbRegisterNumber, TargetRegisterDescriptor> mapping = {
                {0, TargetRegisterDescriptor(0, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {1, TargetRegisterDescriptor(1, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {2, TargetRegisterDescriptor(2, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {3, TargetRegisterDescriptor(3, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {4, TargetRegisterDescriptor(4, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {5, TargetRegisterDescriptor(5, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {6, TargetRegisterDescriptor(6, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {7, TargetRegisterDescriptor(7, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {8, TargetRegisterDescriptor(8, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {9, TargetRegisterDescriptor(9, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {10, TargetRegisterDescriptor(10, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {11, TargetRegisterDescriptor(11, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {12, TargetRegisterDescriptor(12, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {13, TargetRegisterDescriptor(13, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {14, TargetRegisterDescriptor(14, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {15, TargetRegisterDescriptor(15, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {16, TargetRegisterDescriptor(16, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {17, TargetRegisterDescriptor(17, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {18, TargetRegisterDescriptor(18, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {19, TargetRegisterDescriptor(19, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {20, TargetRegisterDescriptor(20, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {21, TargetRegisterDescriptor(21, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {22, TargetRegisterDescriptor(22, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {23, TargetRegisterDescriptor(23, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {24, TargetRegisterDescriptor(24, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {25, TargetRegisterDescriptor(25, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {26, TargetRegisterDescriptor(26, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {27, TargetRegisterDescriptor(27, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {28, TargetRegisterDescriptor(28, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {29, TargetRegisterDescriptor(29, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {30, TargetRegisterDescriptor(30, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {31, TargetRegisterDescriptor(31, TargetRegisterType::GENERAL_PURPOSE_REGISTER)},
                {32, TargetRegisterDescriptor(TargetRegisterType::STATUS_REGISTER)},
                {33, TargetRegisterDescriptor(TargetRegisterType::STACK_POINTER)},
                {34, TargetRegisterDescriptor(TargetRegisterType::PROGRAM_COUNTER)},
            };

            return mapping;
        };

        /**
         * avr-gdb uses the most significant 15 bits in memory addresses to indicate the type of memory being
         * addressed.
         *
         * @param address
         * @return
         */
        Targets::TargetMemoryType getMemoryTypeFromGdbAddress(std::uint32_t address) override {
            if (address & this->gdbInternalMemoryMask) {
                return Targets::TargetMemoryType::RAM;
            }

            return Targets::TargetMemoryType::FLASH;
        };

        /**
         * Strips the most significant 15 bits from a GDB memory address.
         *
         * @param address
         * @return
         */
        std::uint32_t removeMemoryTypeIndicatorFromGdbAddress(std::uint32_t address) override {
            return address & this->gdbInternalMemoryMask ? (address & ~(this->gdbInternalMemoryMask)) : address;
        };

    public:
        AvrGdbRsp(EventManager& eventManager): GdbRspDebugServer(eventManager) {};

        std::string getName() const override {
            return "AVR GDB Remote Serial Protocol Debug Server";
        }
    };
}