/*
 * Copyright (C) 2015, 2016 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __KVM_ARM_VGIC_MMIO_H__
#define __KVM_ARM_VGIC_MMIO_H__

struct vgic_register_region {
	unsigned int reg_offset;
	unsigned int len;
	unsigned int bits_per_irq;
	unsigned int access_flags;
	union {
		unsigned long (*read)(struct kvm_vcpu *vcpu, gpa_t addr,
				      unsigned int len);
		unsigned long (*its_read)(struct kvm *kvm, struct vgic_its *its,
					  gpa_t addr, unsigned int len);
	};
	union {
		void (*write)(struct kvm_vcpu *vcpu, gpa_t addr,
			      unsigned int len, unsigned long val);
		void (*its_write)(struct kvm *kvm, struct vgic_its *its,
				  gpa_t addr, unsigned int len,
				  unsigned long val);
	};
	unsigned long (*uaccess_read)(struct kvm_vcpu *vcpu, gpa_t addr,
				      unsigned int len);
	union {
		void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr,
				      unsigned int len, unsigned long val);
		int (*uaccess_its_write)(struct kvm *kvm, struct vgic_its *its,
					 gpa_t addr, unsigned int len,
					 unsigned long val);
	};
};

extern struct kvm_io_device_ops kvm_io_gic_ops;

#define VGIC_ACCESS_8bit	1
#define VGIC_ACCESS_32bit	2
#define VGIC_ACCESS_64bit	4

/*
 * Generate a mask that covers the number of bytes required to address
 * up to 1024 interrupts, each represented by <bits> bits. This assumes
 * that <bits> is a power of two.
 */
#define VGIC_ADDR_IRQ_MASK(bits) (((bits) * 1024 / 8) - 1)

/*
 * (addr & mask) gives us the _byte_ offset for the INT ID.
 * We multiply this by 8 the get the _bit_ offset, then divide this by
 * the number of bits to learn the actual INT ID.
 * But instead of a division (which requires a "long long div" implementation),
 * we shift by the binary logarithm of <bits>.
 * This assumes that <bits> is a power of two.
 */
#define VGIC_ADDR_TO_INTID(addr, bits)  (((addr) & VGIC_ADDR_IRQ_MASK(bits)) * \
					8 >> ilog2(bits))

/*
 * Some VGIC registers store per-IRQ information, with a different number
 * of bits per IRQ. For those registers this macro is used.
 * The _WITH_LENGTH version instantiates registers with a fixed length
 * and is mutually exclusive with the _PER_IRQ version.
 */
#define REGISTER_DESC_WITH_BITS_PER_IRQ(off, rd, wr, bpi, acc)		\
	{								\
		.reg_offset = off,					\
		.bits_per_irq = bpi,					\
		.len = bpi * 1024 / 8,					\
		.access_flags = acc,					\
		.read = rd,						\
		.write = wr,						\
	}

#define REGISTER_DESC_WITH_LENGTH(off, rd, wr, length, acc)		\
	{								\
		.reg_offset = off,					\
		.bits_per_irq = 0,					\
		.len = length,						\
		.access_flags = acc,					\
		.read = rd,						\
		.write = wr,						\
	}

#define REGISTER_DESC_WITH_LENGTH_UACCESS(off, rd, wr, urd, uwr, length, acc) \
	{								\
		.reg_offset = off,					\
		.bits_per_irq = 0,					\
		.len = length,						\
		.access_flags = acc,					\
		.read = rd,						\
		.write = wr,						\
		.uaccess_read = urd,					\
		.uaccess_write = uwr,					\
	}

int kvm_vgic_register_mmio_region(struct kvm *kvm, struct kvm_vcpu *vcpu,
				  struct vgic_register_region *reg_desc,
				  struct vgic_io_device *region,
				  int nr_irqs, bool offset_private);

unsigned long vgic_data_mmio_bus_to_host(const void *val, unsigned int len);

void vgic_data_host_to_mmio_bus(void *buf, unsigned int len,
				unsigned long data);

unsigned long extract_bytes(u64 data, unsigned int offset,
			    unsigned int num);

u64 update_64bit_reg(u64 reg, unsigned int offset, unsigned int len,
		     unsigned long val);

unsigned long vgic_mmio_read_raz(struct kvm_vcpu *vcpu,
				 gpa_t addr, unsigned int len);

unsigned long vgic_mmio_read_rao(struct kvm_vcpu *vcpu,
				 gpa_t addr, unsigned int len);

void vgic_mmio_write_wi(struct kvm_vcpu *vcpu, gpa_t addr,
			unsigned int len, unsigned long val);

unsigned long vgic_mmio_read_enable(struct kvm_vcpu *vcpu,
				    gpa_t addr, unsigned int len);

void vgic_mmio_write_senable(struct kvm_vcpu *vcpu,
			     gpa_t addr, unsigned int len,
			     unsigned long val);

void vgic_mmio_write_cenable(struct kvm_vcpu *vcpu,
			     gpa_t addr, unsigned int len,
			     unsigned long val);

unsigned long vgic_mmio_read_pending(struct kvm_vcpu *vcpu,
				     gpa_t addr, unsigned int len);

void vgic_mmio_write_spending(struct kvm_vcpu *vcpu,
			      gpa_t addr, unsigned int len,
			      unsigned long val);

void vgic_mmio_write_cpending(struct kvm_vcpu *vcpu,
			      gpa_t addr, unsigned int len,
			      unsigned long val);

unsigned long vgic_mmio_read_active(struct kvm_vcpu *vcpu,
				    gpa_t addr, unsigned int len);

void vgic_mmio_write_cactive(struct kvm_vcpu *vcpu,
			     gpa_t addr, unsigned int len,
			     unsigned long val);

void vgic_mmio_write_sactive(struct kvm_vcpu *vcpu,
			     gpa_t addr, unsigned int len,
			     unsigned long val);

unsigned long vgic_mmio_read_priority(struct kvm_vcpu *vcpu,
				      gpa_t addr, unsigned int len);

void vgic_mmio_write_priority(struct kvm_vcpu *vcpu,
			      gpa_t addr, unsigned int len,
			      unsigned long val);

unsigned long vgic_mmio_read_config(struct kvm_vcpu *vcpu,
				    gpa_t addr, unsigned int len);

void vgic_mmio_write_config(struct kvm_vcpu *vcpu,
			    gpa_t addr, unsigned int len,
			    unsigned long val);

int vgic_uaccess(struct kvm_vcpu *vcpu, struct vgic_io_device *dev,
		 bool is_write, int offset, u32 *val);

u64 vgic_read_irq_line_level_info(struct kvm_vcpu *vcpu, u32 intid);

void vgic_write_irq_line_level_info(struct kvm_vcpu *vcpu, u32 intid,
				    const u64 val);

unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev);

unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev);

u64 vgic_sanitise_outer_cacheability(u64 reg);
u64 vgic_sanitise_inner_cacheability(u64 reg);
u64 vgic_sanitise_shareability(u64 reg);
u64 vgic_sanitise_field(u64 reg, u64 field_mask, int field_shift,
			u64 (*sanitise_fn)(u64));

/* Find the proper register handler entry given a certain address offset */
const struct vgic_register_region *
vgic_find_mmio_region(const struct vgic_register_region *regions,
		      int nr_regions, unsigned int offset);

#endif