cfgbus_multiserial.h

// Copyright 2021-2025 The Aerospace Corporation.
// This file is a part of SatCat5, licensed under CERN-OHL-W v2 or later.
// Partial driver for the multipurpose serial peripheral
 
#pragma once
 
#include <satcat5/cfgbus_interrupt.h>
#include <satcat5/pkt_buffer.h>
 
namespace satcat5 {
    namespace cfg {
        class MultiSerial
            : public    satcat5::cfg::Interrupt
            , protected satcat5::io::EventListener
            , public    satcat5::poll::OnDemand
        {
        public:
            inline u8 get_percent_full() const
                {return m_tx.get_percent_full();}
 
            inline bool idle() const
                {return m_cmd_queued == 0;}
 
        protected:
            MultiSerial(
                satcat5::cfg::ConfigBus* cfg,   // ConfigBus interface object
                unsigned devaddr,               // ConfigBus device address
                unsigned maxpkt,                // Maximum queued commands
                u8* txbuff, unsigned txsize,    // Command buffer (ptr + len)
                u8* rxbuff, unsigned rxsize);   // Reply buffer (ptr + len)
            ~MultiSerial() {}
 
            bool write_check(
                unsigned ncmd,      // Number of opcodes in this transaction
                unsigned nread);    // Number of reads in this transaction
 
            unsigned write_finish();
 
            virtual void read_done(unsigned cidx) = 0;
 
            // ConfigBus register map.
            static const unsigned REGADDR_IRQ;
            static const unsigned REGADDR_CFG;
            static const unsigned REGADDR_STATUS;
            static const unsigned REGADDR_DATA;
 
            // ConfigBus interface object.
            satcat5::cfg::Register m_ctrl;
 
            // Command and reply buffers
            satcat5::io::PacketBuffer m_tx; 
            satcat5::io::PacketBuffer m_rx; 
 
        private:
            // Internal event handlers
            void data_rcvd(satcat5::io::Readable* src) override;
            void irq_event();           // ConfigBus interrupt
            void poll_demand();         // Deferred interrupt
 
            // Internal state, not accessible to children.
            unsigned const m_cmd_max;   // Max queued commands
            unsigned m_cmd_cbidx;       // Index of next callback
            unsigned m_cmd_queued;      // Number of queued commands
            unsigned m_new_wralloc;     // Expected command length of new command
            unsigned m_new_rdalloc;     // Expected reply length for new command
            unsigned m_rdalloc;         // Unallocated space in reply buffer
            unsigned m_irq_wrrem;       // Remaining opcodes in current command
            unsigned m_irq_rdrem;       // Remaining reads in current command
        };
    }
}