/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
 * Copyright (C) 2019 Western Digital Corporation or its affiliates.
 *
 * Authors:
 *     Anup Patel <anup.patel@wdc.com>
 */

#ifndef __LINUX_KVM_RISCV_H
#define __LINUX_KVM_RISCV_H

#ifndef __ASSEMBLY__

#include <linux/types.h>
#include <asm/bitsperlong.h>
#include <asm/ptrace.h>

#define __KVM_HAVE_IRQ_LINE
#define __KVM_HAVE_READONLY_MEM

#define KVM_COALESCED_MMIO_PAGE_OFFSET 1

#define KVM_INTERRUPT_SET	-1U
#define KVM_INTERRUPT_UNSET	-2U

/* for KVM_GET_REGS and KVM_SET_REGS */
struct kvm_regs {
};

/* for KVM_GET_FPU and KVM_SET_FPU */
struct kvm_fpu {
};

/* KVM Debug exit structure */
struct kvm_debug_exit_arch {
};

/* for KVM_SET_GUEST_DEBUG */
struct kvm_guest_debug_arch {
};

/* definition of registers in kvm_run */
struct kvm_sync_regs {
};

/* for KVM_GET_SREGS and KVM_SET_SREGS */
struct kvm_sregs {
};

/* CONFIG registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
struct kvm_riscv_config {
	unsigned long isa;
	unsigned long zicbom_block_size;
	unsigned long mvendorid;
	unsigned long marchid;
	unsigned long mimpid;
	unsigned long zicboz_block_size;
};

/* CORE registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
struct kvm_riscv_core {
	struct user_regs_struct regs;
	unsigned long mode;
};

/* Possible privilege modes for kvm_riscv_core */
#define KVM_RISCV_MODE_S	1
#define KVM_RISCV_MODE_U	0

/* General CSR registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
struct kvm_riscv_csr {
	unsigned long sstatus;
	unsigned long sie;
	unsigned long stvec;
	unsigned long sscratch;
	unsigned long sepc;
	unsigned long scause;
	unsigned long stval;
	unsigned long sip;
	unsigned long satp;
	unsigned long scounteren;
};

/* AIA CSR registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
struct kvm_riscv_aia_csr {
	unsigned long siselect;
	unsigned long iprio1;
	unsigned long iprio2;
	unsigned long sieh;
	unsigned long siph;
	unsigned long iprio1h;
	unsigned long iprio2h;
};

/* TIMER registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
struct kvm_riscv_timer {
	__u64 frequency;
	__u64 time;
	__u64 compare;
	__u64 state;
};

/*
 * ISA extension IDs specific to KVM. This is not the same as the host ISA
 * extension IDs as that is internal to the host and should not be exposed
 * to the guest. This should always be contiguous to keep the mapping simple
 * in KVM implementation.
 */
enum KVM_RISCV_ISA_EXT_ID {
	KVM_RISCV_ISA_EXT_A = 0,
	KVM_RISCV_ISA_EXT_C,
	KVM_RISCV_ISA_EXT_D,
	KVM_RISCV_ISA_EXT_F,
	KVM_RISCV_ISA_EXT_H,
	KVM_RISCV_ISA_EXT_I,
	KVM_RISCV_ISA_EXT_M,
	KVM_RISCV_ISA_EXT_SVPBMT,
	KVM_RISCV_ISA_EXT_SSTC,
	KVM_RISCV_ISA_EXT_SVINVAL,
	KVM_RISCV_ISA_EXT_ZIHINTPAUSE,
	KVM_RISCV_ISA_EXT_ZICBOM,
	KVM_RISCV_ISA_EXT_ZICBOZ,
	KVM_RISCV_ISA_EXT_ZBB,
	KVM_RISCV_ISA_EXT_SSAIA,
	KVM_RISCV_ISA_EXT_V,
	KVM_RISCV_ISA_EXT_SVNAPOT,
	KVM_RISCV_ISA_EXT_MAX,
};

/*
 * SBI extension IDs specific to KVM. This is not the same as the SBI
 * extension IDs defined by the RISC-V SBI specification.
 */
enum KVM_RISCV_SBI_EXT_ID {
	KVM_RISCV_SBI_EXT_V01 = 0,
	KVM_RISCV_SBI_EXT_TIME,
	KVM_RISCV_SBI_EXT_IPI,
	KVM_RISCV_SBI_EXT_RFENCE,
	KVM_RISCV_SBI_EXT_SRST,
	KVM_RISCV_SBI_EXT_HSM,
	KVM_RISCV_SBI_EXT_PMU,
	KVM_RISCV_SBI_EXT_EXPERIMENTAL,
	KVM_RISCV_SBI_EXT_VENDOR,
	KVM_RISCV_SBI_EXT_MAX,
};

/* Possible states for kvm_riscv_timer */
#define KVM_RISCV_TIMER_STATE_OFF	0
#define KVM_RISCV_TIMER_STATE_ON	1

#define KVM_REG_SIZE(id)		\
	(1U << (((id) & KVM_REG_SIZE_MASK) >> KVM_REG_SIZE_SHIFT))

/* If you need to interpret the index values, here is the key: */
#define KVM_REG_RISCV_TYPE_MASK		0x00000000FF000000
#define KVM_REG_RISCV_TYPE_SHIFT	24
#define KVM_REG_RISCV_SUBTYPE_MASK	0x0000000000FF0000
#define KVM_REG_RISCV_SUBTYPE_SHIFT	16

/* Config registers are mapped as type 1 */
#define KVM_REG_RISCV_CONFIG		(0x01 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_CONFIG_REG(name)	\
	(offsetof(struct kvm_riscv_config, name) / sizeof(unsigned long))

/* Core registers are mapped as type 2 */
#define KVM_REG_RISCV_CORE		(0x02 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_CORE_REG(name)	\
		(offsetof(struct kvm_riscv_core, name) / sizeof(unsigned long))

/* Control and status registers are mapped as type 3 */
#define KVM_REG_RISCV_CSR		(0x03 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_CSR_GENERAL	(0x0 << KVM_REG_RISCV_SUBTYPE_SHIFT)
#define KVM_REG_RISCV_CSR_AIA		(0x1 << KVM_REG_RISCV_SUBTYPE_SHIFT)
#define KVM_REG_RISCV_CSR_REG(name)	\
		(offsetof(struct kvm_riscv_csr, name) / sizeof(unsigned long))
#define KVM_REG_RISCV_CSR_AIA_REG(name)	\
	(offsetof(struct kvm_riscv_aia_csr, name) / sizeof(unsigned long))

/* Timer registers are mapped as type 4 */
#define KVM_REG_RISCV_TIMER		(0x04 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_TIMER_REG(name)	\
		(offsetof(struct kvm_riscv_timer, name) / sizeof(__u64))

/* F extension registers are mapped as type 5 */
#define KVM_REG_RISCV_FP_F		(0x05 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_FP_F_REG(name)	\
		(offsetof(struct __riscv_f_ext_state, name) / sizeof(__u32))

/* D extension registers are mapped as type 6 */
#define KVM_REG_RISCV_FP_D		(0x06 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_FP_D_REG(name)	\
		(offsetof(struct __riscv_d_ext_state, name) / sizeof(__u64))

/* ISA Extension registers are mapped as type 7 */
#define KVM_REG_RISCV_ISA_EXT		(0x07 << KVM_REG_RISCV_TYPE_SHIFT)

/* SBI extension registers are mapped as type 8 */
#define KVM_REG_RISCV_SBI_EXT		(0x08 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_SBI_SINGLE	(0x0 << KVM_REG_RISCV_SUBTYPE_SHIFT)
#define KVM_REG_RISCV_SBI_MULTI_EN	(0x1 << KVM_REG_RISCV_SUBTYPE_SHIFT)
#define KVM_REG_RISCV_SBI_MULTI_DIS	(0x2 << KVM_REG_RISCV_SUBTYPE_SHIFT)
#define KVM_REG_RISCV_SBI_MULTI_REG(__ext_id)	\
		((__ext_id) / __BITS_PER_LONG)
#define KVM_REG_RISCV_SBI_MULTI_MASK(__ext_id)	\
		(1UL << ((__ext_id) % __BITS_PER_LONG))
#define KVM_REG_RISCV_SBI_MULTI_REG_LAST	\
		KVM_REG_RISCV_SBI_MULTI_REG(KVM_RISCV_SBI_EXT_MAX - 1)

/* V extension registers are mapped as type 9 */
#define KVM_REG_RISCV_VECTOR		(0x09 << KVM_REG_RISCV_TYPE_SHIFT)
#define KVM_REG_RISCV_VECTOR_CSR_REG(name)	\
		(offsetof(struct __riscv_v_ext_state, name) / sizeof(unsigned long))
#define KVM_REG_RISCV_VECTOR_REG(n)	\
		((n) + sizeof(struct __riscv_v_ext_state) / sizeof(unsigned long))

/* Device Control API: RISC-V AIA */
#define KVM_DEV_RISCV_APLIC_ALIGN		0x1000
#define KVM_DEV_RISCV_APLIC_SIZE		0x4000
#define KVM_DEV_RISCV_APLIC_MAX_HARTS		0x4000
#define KVM_DEV_RISCV_IMSIC_ALIGN		0x1000
#define KVM_DEV_RISCV_IMSIC_SIZE		0x1000

#define KVM_DEV_RISCV_AIA_GRP_CONFIG		0
#define KVM_DEV_RISCV_AIA_CONFIG_MODE		0
#define KVM_DEV_RISCV_AIA_CONFIG_IDS		1
#define KVM_DEV_RISCV_AIA_CONFIG_SRCS		2
#define KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS	3
#define KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT	4
#define KVM_DEV_RISCV_AIA_CONFIG_HART_BITS	5
#define KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS	6

/*
 * Modes of RISC-V AIA device:
 * 1) EMUL (aka Emulation): Trap-n-emulate IMSIC
 * 2) HWACCEL (aka HW Acceleration): Virtualize IMSIC using IMSIC guest files
 * 3) AUTO (aka Automatic): Virtualize IMSIC using IMSIC guest files whenever
 *    available otherwise fallback to trap-n-emulation
 */
#define KVM_DEV_RISCV_AIA_MODE_EMUL		0
#define KVM_DEV_RISCV_AIA_MODE_HWACCEL		1
#define KVM_DEV_RISCV_AIA_MODE_AUTO		2

#define KVM_DEV_RISCV_AIA_IDS_MIN		63
#define KVM_DEV_RISCV_AIA_IDS_MAX		2048
#define KVM_DEV_RISCV_AIA_SRCS_MAX		1024
#define KVM_DEV_RISCV_AIA_GROUP_BITS_MAX	8
#define KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN	24
#define KVM_DEV_RISCV_AIA_GROUP_SHIFT_MAX	56
#define KVM_DEV_RISCV_AIA_HART_BITS_MAX		16
#define KVM_DEV_RISCV_AIA_GUEST_BITS_MAX	8

#define KVM_DEV_RISCV_AIA_GRP_ADDR		1
#define KVM_DEV_RISCV_AIA_ADDR_APLIC		0
#define KVM_DEV_RISCV_AIA_ADDR_IMSIC(__vcpu)	(1 + (__vcpu))
#define KVM_DEV_RISCV_AIA_ADDR_MAX		\
		(1 + KVM_DEV_RISCV_APLIC_MAX_HARTS)

#define KVM_DEV_RISCV_AIA_GRP_CTRL		2
#define KVM_DEV_RISCV_AIA_CTRL_INIT		0

/*
 * The device attribute type contains the memory mapped offset of the
 * APLIC register (range 0x0000-0x3FFF) and it must be 4-byte aligned.
 */
#define KVM_DEV_RISCV_AIA_GRP_APLIC		3

/*
 * The lower 12-bits of the device attribute type contains the iselect
 * value of the IMSIC register (range 0x70-0xFF) whereas the higher order
 * bits contains the VCPU id.
 */
#define KVM_DEV_RISCV_AIA_GRP_IMSIC		4
#define KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS	12
#define KVM_DEV_RISCV_AIA_IMSIC_ISEL_MASK	\
		((1U << KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS) - 1)
#define KVM_DEV_RISCV_AIA_IMSIC_MKATTR(__vcpu, __isel)	\
		(((__vcpu) << KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS) | \
		 ((__isel) & KVM_DEV_RISCV_AIA_IMSIC_ISEL_MASK))
#define KVM_DEV_RISCV_AIA_IMSIC_GET_ISEL(__attr)	\
		((__attr) & KVM_DEV_RISCV_AIA_IMSIC_ISEL_MASK)
#define KVM_DEV_RISCV_AIA_IMSIC_GET_VCPU(__attr)	\
		((__attr) >> KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS)

/* One single KVM irqchip, ie. the AIA */
#define KVM_NR_IRQCHIPS			1

#endif

#endif /* __LINUX_KVM_RISCV_H */