root/arch/x86/include/asm/x86_init.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_PLATFORM_H
#define _ASM_X86_PLATFORM_H

struct ghcb;
struct mpc_bus;
struct mpc_cpu;
struct pt_regs;
struct mpc_table;
struct cpuinfo_x86;
struct irq_domain;

/**
 * struct x86_init_mpparse - platform specific mpparse ops
 * @setup_ioapic_ids:           platform specific ioapic id override
 * @find_mptable:               Find MPTABLE early to reserve the memory region
 * @early_parse_smp_cfg:        Parse the SMP configuration data early before initmem_init()
 * @parse_smp_cfg:              Parse the SMP configuration data
 */
struct x86_init_mpparse {
        void (*setup_ioapic_ids)(void);
        void (*find_mptable)(void);
        void (*early_parse_smp_cfg)(void);
        void (*parse_smp_cfg)(void);
};

/**
 * struct x86_init_resources - platform specific resource related ops
 * @probe_roms:                 probe BIOS roms
 * @reserve_resources:          reserve the standard resources for the
 *                              platform
 * @memory_setup:               platform specific memory setup
 * @dmi_setup:                  platform specific DMI setup
 */
struct x86_init_resources {
        void (*probe_roms)(void);
        void (*reserve_resources)(void);
        char *(*memory_setup)(void);
        void (*dmi_setup)(void);
};

/**
 * struct x86_init_irqs - platform specific interrupt setup
 * @pre_vector_init:            init code to run before interrupt vectors
 *                              are set up.
 * @intr_init:                  interrupt init code
 * @intr_mode_select:           interrupt delivery mode selection
 * @intr_mode_init:             interrupt delivery mode setup
 * @create_pci_msi_domain:      Create the PCI/MSI interrupt domain
 */
struct x86_init_irqs {
        void (*pre_vector_init)(void);
        void (*intr_init)(void);
        void (*intr_mode_select)(void);
        void (*intr_mode_init)(void);
        struct irq_domain *(*create_pci_msi_domain)(void);
};

/**
 * struct x86_init_oem - oem platform specific customizing functions
 * @arch_setup:                 platform specific architecture setup
 * @banner:                     print a platform specific banner
 */
struct x86_init_oem {
        void (*arch_setup)(void);
        void (*banner)(void);
};

/**
 * struct x86_init_paging - platform specific paging functions
 * @pagetable_init:     platform specific paging initialization call to setup
 *                      the kernel pagetables and prepare accessors functions.
 *                      Callback must call paging_init(). Called once after the
 *                      direct mapping for phys memory is available.
 */
struct x86_init_paging {
        void (*pagetable_init)(void);
};

/**
 * struct x86_init_timers - platform specific timer setup
 * @setup_percpu_clockev:       set up the per cpu clock event device for the
 *                              boot cpu
 * @timer_init:                 initialize the platform timer (default PIT/HPET)
 * @wallclock_init:             init the wallclock device
 */
struct x86_init_timers {
        void (*setup_percpu_clockev)(void);
        void (*timer_init)(void);
        void (*wallclock_init)(void);
};

/**
 * struct x86_init_iommu - platform specific iommu setup
 * @iommu_init:                 platform specific iommu setup
 */
struct x86_init_iommu {
        int (*iommu_init)(void);
};

/**
 * struct x86_init_pci - platform specific pci init functions
 * @arch_init:                  platform specific pci arch init call
 * @init:                       platform specific pci subsystem init
 * @init_irq:                   platform specific pci irq init
 * @fixup_irqs:                 platform specific pci irq fixup
 */
struct x86_init_pci {
        int (*arch_init)(void);
        int (*init)(void);
        void (*init_irq)(void);
        void (*fixup_irqs)(void);
};

/**
 * struct x86_hyper_init - x86 hypervisor init functions
 * @init_platform:              platform setup
 * @guest_late_init:            guest late init
 * @x2apic_available:           X2APIC detection
 * @msi_ext_dest_id:            MSI supports 15-bit APIC IDs
 * @init_mem_mapping:           setup early mappings during init_mem_mapping()
 * @init_after_bootmem:         guest init after boot allocator is finished
 */
struct x86_hyper_init {
        void (*init_platform)(void);
        void (*guest_late_init)(void);
        bool (*x2apic_available)(void);
        bool (*msi_ext_dest_id)(void);
        void (*init_mem_mapping)(void);
        void (*init_after_bootmem)(void);
};

/**
 * struct x86_init_acpi - x86 ACPI init functions
 * @set_root_pointer:           set RSDP address
 * @get_root_pointer:           get RSDP address
 * @reduced_hw_early_init:      hardware reduced platform early init
 */
struct x86_init_acpi {
        void (*set_root_pointer)(u64 addr);
        u64 (*get_root_pointer)(void);
        void (*reduced_hw_early_init)(void);
};

/**
 * struct x86_guest - Functions used by misc guest incarnations like SEV, TDX, etc.
 *
 * @enc_status_change_prepare:  Notify HV before the encryption status of a range is changed
 * @enc_status_change_finish:   Notify HV after the encryption status of a range is changed
 * @enc_tlb_flush_required:     Returns true if a TLB flush is needed before changing page encryption status
 * @enc_cache_flush_required:   Returns true if a cache flush is needed before changing page encryption status
 * @enc_kexec_begin:            Begin the two-step process of converting shared memory back
 *                              to private. It stops the new conversions from being started
 *                              and waits in-flight conversions to finish, if possible.
 * @enc_kexec_finish:           Finish the two-step process of converting shared memory to
 *                              private. All memory is private after the call when
 *                              the function returns.
 *                              It is called on only one CPU while the others are shut down
 *                              and with interrupts disabled.
 */
struct x86_guest {
        int (*enc_status_change_prepare)(unsigned long vaddr, int npages, bool enc);
        int (*enc_status_change_finish)(unsigned long vaddr, int npages, bool enc);
        bool (*enc_tlb_flush_required)(bool enc);
        bool (*enc_cache_flush_required)(void);
        void (*enc_kexec_begin)(void);
        void (*enc_kexec_finish)(void);
};

/**
 * struct x86_init_ops - functions for platform specific setup
 *
 */
struct x86_init_ops {
        struct x86_init_resources       resources;
        struct x86_init_mpparse         mpparse;
        struct x86_init_irqs            irqs;
        struct x86_init_oem             oem;
        struct x86_init_paging          paging;
        struct x86_init_timers          timers;
        struct x86_init_iommu           iommu;
        struct x86_init_pci             pci;
        struct x86_hyper_init           hyper;
        struct x86_init_acpi            acpi;
};

/**
 * struct x86_cpuinit_ops - platform specific cpu hotplug setups
 * @setup_percpu_clockev:       set up the per cpu clock event device
 * @early_percpu_clock_init:    early init of the per cpu clock event device
 * @fixup_cpu_id:               fixup function for cpuinfo_x86::topo.pkg_id
 * @parallel_bringup:           Parallel bringup control
 */
struct x86_cpuinit_ops {
        void (*setup_percpu_clockev)(void);
        void (*early_percpu_clock_init)(void);
        void (*fixup_cpu_id)(struct cpuinfo_x86 *c, int node);
        bool parallel_bringup;
};

struct timespec64;

/**
 * struct x86_legacy_devices - legacy x86 devices
 *
 * @pnpbios: this platform can have a PNPBIOS. If this is disabled the platform
 *      is known to never have a PNPBIOS.
 *
 * These are devices known to require LPC or ISA bus. The definition of legacy
 * devices adheres to the ACPI 5.2.9.3 IA-PC Boot Architecture flag
 * ACPI_FADT_LEGACY_DEVICES. These devices consist of user visible devices on
 * the LPC or ISA bus. User visible devices are devices that have end-user
 * accessible connectors (for example, LPT parallel port). Legacy devices on
 * the LPC bus consist for example of serial and parallel ports, PS/2 keyboard
 * / mouse, and the floppy disk controller. A system that lacks all known
 * legacy devices can assume all devices can be detected exclusively via
 * standard device enumeration mechanisms including the ACPI namespace.
 *
 * A system which has does not have ACPI_FADT_LEGACY_DEVICES enabled must not
 * have any of the legacy devices enumerated below present.
 */
struct x86_legacy_devices {
        int pnpbios;
};

/**
 * enum x86_legacy_i8042_state - i8042 keyboard controller state
 * @X86_LEGACY_I8042_PLATFORM_ABSENT: the controller is always absent on
 *      given platform/subarch.
 * @X86_LEGACY_I8042_FIRMWARE_ABSENT: firmware reports that the controller
 *      is absent.
 * @X86_LEGACY_I8042_EXPECTED_PRESENT: the controller is likely to be
 *      present, the i8042 driver should probe for controller existence.
 */
enum x86_legacy_i8042_state {
        X86_LEGACY_I8042_PLATFORM_ABSENT,
        X86_LEGACY_I8042_FIRMWARE_ABSENT,
        X86_LEGACY_I8042_EXPECTED_PRESENT,
};

/**
 * struct x86_legacy_features - legacy x86 features
 *
 * @i8042: indicated if we expect the device to have i8042 controller
 *      present.
 * @rtc: this device has a CMOS real-time clock present
 * @warm_reset: 1 if platform allows warm reset, else 0
 * @no_vga: 1 if (FADT.boot_flags & ACPI_FADT_NO_VGA) is set, else 0
 * @reserve_bios_regions: boot code will search for the EBDA address and the
 *      start of the 640k - 1M BIOS region.  If false, the platform must
 *      ensure that its memory map correctly reserves sub-1MB regions as needed.
 * @devices: legacy x86 devices, refer to struct x86_legacy_devices
 *      documentation for further details.
 */
struct x86_legacy_features {
        enum x86_legacy_i8042_state i8042;
        int rtc;
        int warm_reset;
        int no_vga;
        int reserve_bios_regions;
        struct x86_legacy_devices devices;
};

/**
 * struct x86_hyper_runtime - x86 hypervisor specific runtime callbacks
 *
 * @pin_vcpu:                   pin current vcpu to specified physical
 *                              cpu (run rarely)
 * @sev_es_hcall_prepare:       Load additional hypervisor-specific
 *                              state into the GHCB when doing a VMMCALL under
 *                              SEV-ES. Called from the #VC exception handler.
 * @sev_es_hcall_finish:        Copies state from the GHCB back into the
 *                              processor (or pt_regs). Also runs checks on the
 *                              state returned from the hypervisor after a
 *                              VMMCALL under SEV-ES.  Needs to return 'false'
 *                              if the checks fail.  Called from the #VC
 *                              exception handler.
 * @is_private_mmio:            For CoCo VMs, must map MMIO address as private.
 *                              Used when device is emulated by a paravisor
 *                              layer in the VM context.
 */
struct x86_hyper_runtime {
        void (*pin_vcpu)(int cpu);
        void (*sev_es_hcall_prepare)(struct ghcb *ghcb, struct pt_regs *regs);
        bool (*sev_es_hcall_finish)(struct ghcb *ghcb, struct pt_regs *regs);
        bool (*is_private_mmio)(u64 addr);
};

/**
 * struct x86_platform_ops - platform specific runtime functions
 * @calibrate_cpu:              calibrate CPU
 * @calibrate_tsc:              calibrate TSC, if different from CPU
 * @get_wallclock:              get time from HW clock like RTC etc.
 * @set_wallclock:              set time back to HW clock
 * @iommu_shutdown:             set by an IOMMU driver for shutdown if necessary
 * @is_untracked_pat_range:     exclude from PAT logic
 * @nmi_init:                   enable NMI on cpus
 * @get_nmi_reason:             get the reason an NMI was received
 * @save_sched_clock_state:     save state for sched_clock() on suspend
 * @restore_sched_clock_state:  restore state for sched_clock() on resume
 * @apic_post_init:             adjust apic if needed
 * @legacy:                     legacy features
 * @set_legacy_features:        override legacy features. Use of this callback
 *                              is highly discouraged. You should only need
 *                              this if your hardware platform requires further
 *                              custom fine tuning far beyond what may be
 *                              possible in x86_early_init_platform_quirks() by
 *                              only using the current x86_hardware_subarch
 *                              semantics.
 * @realmode_reserve:           reserve memory for realmode trampoline
 * @realmode_init:              initialize realmode trampoline
 * @hyper:                      x86 hypervisor specific runtime callbacks
 * @guest:                      guest incarnations callbacks
 */
struct x86_platform_ops {
        unsigned long (*calibrate_cpu)(void);
        unsigned long (*calibrate_tsc)(void);
        void (*get_wallclock)(struct timespec64 *ts);
        int (*set_wallclock)(const struct timespec64 *ts);
        void (*iommu_shutdown)(void);
        bool (*is_untracked_pat_range)(u64 start, u64 end);
        void (*nmi_init)(void);
        unsigned char (*get_nmi_reason)(void);
        void (*save_sched_clock_state)(void);
        void (*restore_sched_clock_state)(void);
        void (*apic_post_init)(void);
        struct x86_legacy_features legacy;
        void (*set_legacy_features)(void);
        void (*realmode_reserve)(void);
        void (*realmode_init)(void);
        struct x86_hyper_runtime hyper;
        struct x86_guest guest;
};

struct x86_apic_ops {
        unsigned int    (*io_apic_read)   (unsigned int apic, unsigned int reg);
        void            (*restore)(void);
};

extern struct x86_init_ops x86_init;
extern struct x86_cpuinit_ops x86_cpuinit;
extern struct x86_platform_ops x86_platform;
extern struct x86_msi_ops x86_msi;
extern struct x86_apic_ops x86_apic_ops;

extern void x86_early_init_platform_quirks(void);
extern void x86_init_noop(void);
extern void x86_init_uint_noop(unsigned int unused);
extern bool bool_x86_init_noop(void);
extern void x86_op_int_noop(int cpu);
extern bool x86_pnpbios_disabled(void);
extern int set_rtc_noop(const struct timespec64 *now);
extern void get_rtc_noop(struct timespec64 *now);

#endif