// SPDX-License-Identifier: GPL-2.0
#ifndef PCI_H
#define PCI_H
/*
 * Provides functions to perform PCI configuration space reads and writes.
 *
 * Copyright (C) 2020-2021 Martin Whitaker.
 */

#include <stdint.h>

#define PCI_MAX_BUS     256
#define PCI_MAX_DEV     32
#define PCI_MAX_FUNC    8

/*
 * Initialises the PCI access support.
 */
void pci_init(void);

/*
 * Returns an 8 bit value read from the specified bus+device+function+register
 * address in the PCI configuration address space.
 */
uint8_t pci_config_read8(int bus, int dev, int func, int reg);

/*
 * Returns a 16 bit value read from the specified bus+device+function+register
 * address in the PCI configuration address space. The address must be 16-bit
 * aligned.
 */
uint16_t pci_config_read16(int bus, int dev, int func, int reg);

/*
 * Returns a 32 bit value read from the specified bus+device+function+register
 * address in the PCI configuration address space. The address must be 32-bit
 * aligned.
 */
uint32_t pci_config_read32(int bus, int dev, int func, int reg);

/*
 * Writes an 8 bit value to the specified bus+device+function+register address
 * in the PCI configuration address space.
 */
void pci_config_write8(int bus, int dev, int func, int reg, uint8_t value);

/*
 * Writes a 16 bit value to the specified bus+device+function+register address
 * in the PCI configuration address space. The address must be 16-bit aligned.
 */
void pci_config_write16(int bus, int dev, int func, int reg, uint16_t value);

/*
 * Writes a 32 bit value to the specified bus+device+function+register address
 * in the PCI configuration address space. The address must be 32-bit aligned.
 */
void pci_config_write32(int bus, int dev, int func, int reg, uint32_t value);

#endif // PCI_H