Kconfig

mainmenu "Twan Configuration"

# Hardware

config NUM_CPUS
    int "Num CPUs"
    range 1 256
    default 32
    ---help---
        Maximum CPU count

config NUM_IOAPICS
    int "Num IOAPICs"
    range 1 15
    default 1
    ---help---
        Maximum IOAPIC count

# Kernel

config KERNEL_SCHED_AGING
    bool "Kernel sched aging"
    default n
    ---help---
        Enable kernel task aging

config KERNEL_SCHED_GLOBAL_QUEUE
    bool "Kernel sched global queue"
    default n
    ---help---
        Enable global kernel scheduling queue across all cores

config KERNEL_SCHED_TASK_STACK_SIZE
    int "Kernel sched task stack size"
    range 2048 4294967295
    default 2048
    ---help---
        Stack size for dynamically created kernel tasks

config KERNEL_SCHED_NUM_CRITICALITIES
    int "Kernel sched num criticalities"
    range 1 255
    default 5
    ---help---
        Criticality level count for kernel tasks

config KERNEL_SCHED_TIME_SLICE_MS
    int "Kernel sched timeslice ms"
    range 1 4294967295
    default 10
    ---help---
        Kernel task time slice in milliseconds

config KERNEL_MAX_HEAP_SIZE
    int "Kernel maximum heap size"
    range 0 1073741824
    default 1073741824
    ---help---
        Maximum amount of memory reserved for kernel heap

config KERNEL_MAX_VMA_PARTITIONS
    int "Kernel maximum VMA paritions"
    range 2 261632
    default 512
    ---help---
        Maximum number of kernel VMA partitions

# Subsys

config SUBSYS_SHUTDOWN
    bool "Enable shutdown subsystem"
    default n

config SUBSYS_WATCHDOG
    bool "Enable watchdog subsystem"
    default n

config SUBSYS_MUTEX
    bool "Enable mutexes"
    default y

config SUBSYS_SEMAPHORE
    bool "Enable semaphores"
    default y

config SUBSYS_TWANVISOR
    bool "Enable twanvisor subsystem"
    default y

config SUBSYS_CLOCK
    bool "Enable clock subsystem"
    default y

config SUBSYS_SLEEP
    bool "Enable sleep subsystem"
    default y

config SUBSYS_TIMEOUT
    bool "Enable timeout subsystem"
    default y

if SUBSYS_TWANVISOR

    config TWANVISOR_VSCHED_STRICT
        bool "Twanvisor strict scheduling"
        default n
        ---help---
            Disable the ability for vcpus to yield or be paused, this config
            will also disallow the creation of vcpus which boot in a paused
            state

    if !TWANVISOR_VSCHED_STRICT

        config TWANVISOR_PV_LOCKS
            bool "Paravirt locks"
            default y
            ---help---
                Enable kernel paravirtualised locking

        config TWANVISOR_PV_LOCK_THRESHOLD
            depends on TWANVISOR_PV_LOCKS
            int "Paravirt lock threshold"
            range 0 4294967295
            default 32768
            ---help---
                Number of iterations before making a vcall under lock contention

        config TWANVISOR_PV_IPIS
            bool "Paravirt IPIs"
            default y
            ---help---
                Enable kernel paravirtualised IPIs

        config TWANVISOR_PV_IPI_THRESHOLD
            depends on TWANVISOR_PV_IPIS
            int "Paravirt IPI threshold"
            range 0 4294967295
            default 32768
            ---help---
                Number of iterations before making a vcall during IPIs

        config TWANVISOR_VIPI_DRAIN_STRICT
            bool "Twanvisor strict VIPI draining"
            default y
            ---help---
                Enable strict IPI draining in Twanvisor to mitigate IPI based
                covert channels

    endif # !TWANVISOR_VSCHED_STRICT

    choice 

        prompt "Twanvisor Scheduler"
        default TWANVISOR_VSCHED_MCQS

        config TWANVISOR_VSCHED_MCQS
            bool "Mixed-Criticality Queued scheduler"

        config TWANVISOR_VSCHED_MCFS
            bool "Mixed-Criticality Frame scheduler"

    endchoice

    config TWANVISOR_VSCHED_NUM_FRAMES
        depends on TWANVISOR_VSCHED_MCFS
        int "Twanvisor num frames"
        range 1 1024
        default 512
        ---help---
            Max number of MCFS frames used by Twanvisor

    config TWANVISOR_VSCHED_NUM_CRITICALITIES
        int "Twanvisor num criticalities"
        range 1 255
        default 5
        ---help---
            Criticality level count for twanvisor guests

    config TWANVISOR_NUM_VTIMERS
        int "Twanvisor num vtimers"
        range 3 255
        default 3
        ---help---
            Number of virtual timers Twanvisor exposes to guests

    config VDBG_PANIC_ON_BUG
        bool "Vpanic when VBUG checks flag a bug"
        default n

    config VDBG_VDYNAMIC_ASSERT
        bool "Enable twanvisor dynamic assertations"
        default y

    config MITIGATION_SPECTRE_RSB
        bool "Enable Spectre-RSB mitigations"
        default y

    config MITIGATION_INTRAMODE_BTI
        bool "Enable mitigations for chaining Branch History Injection to Branch Target Injection"
        default y

    config MITIGATION_BHI
        bool "Enable mitigations for Branch History Injection"
        default y

    config MITIGATION_BTI
        bool "Enable mitigations for Branch Target Injection"
        default y

    config MITIGATION_MDS
        bool "Enable mitigations for Microarchitectural Data Sampling"
        default y

    config MITIGATION_L1TF
        bool "Enable mitigations for L1 Terminal Fault"
        default y

    config MITIGATION_RETBLEED_S
        bool "Enable mitigations for retbleed in supervisor modes"
        default y

    config MITIGATION_RETBLEED_U
        bool "Enable mitigations for retbleed in user modes"
        default y

    config DISABLE_SSTLF
        bool "Disable speculative store to load forwarding"
        default y

    config DISABLE_SSB
        bool "Disable speculative store bypass"
        default y

    config DISABLE_DDP_U
        bool "Disable data dependant prefetchers in user modes"
        default n

    config DISABLE_BRANCH_PREDICTION_S
        bool "Disable branch prediction in supervisor modes"
        default n

    config DISABLE_BRANCH_PREDICTION_U
        bool "Disable branch prediction in user modes"
        default n

endif # SUBSYS_TWANVISOR

# Kdbg

config KDBG_PANIC_ON_BUG
    bool "Kpanic when KBUG checks flag a bug"
    default n

config KDBG_KDYNAMIC_ASSERT
    bool "Enable kernel dynamic assertations"
    default y

# Demos

config DEMO_EARLY_INITCALLS
    bool "Enable demo for early initicalls"
    default n

config DEMO_LATE_INITCALLS
    bool "Enable demo for late initicalls"
    default n

config DEMO_DRIVERS
    bool "Enable demo for drivers"
    default n

config DEMO_PV_TWANVISOR
    depends on SUBSYS_TWANVISOR
    bool "Enable demo for twanvisor"
    default n