pci_io.h

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#ifndef _IPXE_PCI_IO_H
#define _IPXE_PCI_IO_H

/** @file
 *
 * PCI I/O API
 *
 */

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
FILE_SECBOOT ( PERMITTED );

#include <stdint.h>
#include <ipxe/api.h>
#include <ipxe/tables.h>
#include <ipxe/iomap.h>
#include <config/ioapi.h>

struct pci_device;
struct pci_api;

/** A PCI bus:dev.fn address range */
struct pci_range {
        /** Starting bus:dev.fn address */
        uint32_t start;
        /** Number of bus:dev.fn addresses within this range */
        unsigned int count;
};

#define PCI_BUSDEVFN( segment, bus, slot, func )                        \
        ( ( (segment) << 16 ) | ( (bus) << 8 ) |                        \
          ( (slot) << 3 ) | ( (func) << 0 ) )

/**
 * Calculate static inline PCI I/O API function name
 *
 * @v _prefix           Subsystem prefix
 * @v _api_func         API function
 * @ret _subsys_func    Subsystem API function
 */
#define PCIAPI_INLINE( _subsys, _api_func ) \
        SINGLE_API_INLINE ( PCIAPI_PREFIX_ ## _subsys, _api_func )

/**
 * Provide a PCI I/O API implementation
 *
 * @v _prefix           Subsystem prefix
 * @v _api_func         API function
 * @v _func             Implementing function
 */
#define PROVIDE_PCIAPI( _subsys, _api_func, _func ) \
        PROVIDE_SINGLE_API ( PCIAPI_PREFIX_ ## _subsys, _api_func, _func )

/**
 * Provide a static inline PCI I/O API implementation
 *
 * @v _prefix           Subsystem prefix
 * @v _api_func         API function
 */
#define PROVIDE_PCIAPI_INLINE( _subsys, _api_func ) \
        PROVIDE_SINGLE_API_INLINE ( PCIAPI_PREFIX_ ## _subsys, _api_func )

/* Include all architecture-independent I/O API headers */
#include <ipxe/null_pci.h>
#include <ipxe/ecam_io.h>
#include <ipxe/pcicloud.h>
#include <ipxe/efi/efi_pci_api.h>
#include <ipxe/linux/linux_pci.h>

/* Include all architecture-dependent I/O API headers */
#include <bits/pci_io.h>

/**
 * Check if PCI bus probing is allowed
 *
 * @v pci               PCI device
 * @ret ok              Bus probing is allowed
 */
int pci_can_probe ( struct pci_device *pci );

/**
 * Find next PCI bus:dev.fn address range in system
 *
 * @v busdevfn          Starting PCI bus:dev.fn address
 * @v range             PCI bus:dev.fn address range to fill in
 */
void pci_discover ( uint32_t busdevfn, struct pci_range *range );

/**
 * Read byte from PCI configuration space
 *
 * @v pci       PCI device
 * @v where     Location within PCI configuration space
 * @v value     Value read
 * @ret rc      Return status code
 */
int pci_read_config_byte ( struct pci_device *pci, unsigned int where,
                           uint8_t *value );

/**
 * Read 16-bit word from PCI configuration space
 *
 * @v pci       PCI device
 * @v where     Location within PCI configuration space
 * @v value     Value read
 * @ret rc      Return status code
 */
int pci_read_config_word ( struct pci_device *pci, unsigned int where,
                           uint16_t *value );

/**
 * Read 32-bit dword from PCI configuration space
 *
 * @v pci       PCI device
 * @v where     Location within PCI configuration space
 * @v value     Value read
 * @ret rc      Return status code
 */
int pci_read_config_dword ( struct pci_device *pci, unsigned int where,
                            uint32_t *value );

/**
 * Write byte to PCI configuration space
 *
 * @v pci       PCI device
 * @v where     Location within PCI configuration space
 * @v value     Value to be written
 * @ret rc      Return status code
 */
int pci_write_config_byte ( struct pci_device *pci, unsigned int where,
                            uint8_t value );

/**
 * Write 16-bit word to PCI configuration space
 *
 * @v pci       PCI device
 * @v where     Location within PCI configuration space
 * @v value     Value to be written
 * @ret rc      Return status code
 */
int pci_write_config_word ( struct pci_device *pci, unsigned int where,
                            uint16_t value );

/**
 * Write 32-bit dword to PCI configuration space
 *
 * @v pci       PCI device
 * @v where     Location within PCI configuration space
 * @v value     Value to be written
 * @ret rc      Return status code
 */
int pci_write_config_dword ( struct pci_device *pci, unsigned int where,
                             uint32_t value );

/**
 * Map PCI bus address as an I/O address
 *
 * @v bus_addr          PCI bus address
 * @v len               Length of region
 * @ret io_addr         I/O address, or NULL on error
 */
void * pci_ioremap ( struct pci_device *pci, unsigned long bus_addr,
                     size_t len );

/** A runtime selectable PCI I/O API */
struct pci_api {
        const char *name;
        typeof ( pci_can_probe ) ( * pci_can_probe );
        typeof ( pci_discover ) ( * pci_discover );
        typeof ( pci_read_config_byte ) ( * pci_read_config_byte );
        typeof ( pci_read_config_word ) ( * pci_read_config_word );
        typeof ( pci_read_config_dword ) ( * pci_read_config_dword );
        typeof ( pci_write_config_byte ) ( * pci_write_config_byte );
        typeof ( pci_write_config_word ) ( * pci_write_config_word );
        typeof ( pci_write_config_dword ) ( * pci_write_config_dword );
        typeof ( pci_ioremap ) ( * pci_ioremap );
};

/** Runtime selectable PCI API table */
#define PCI_APIS __table ( struct pci_api, "pci_apis" )

/**
 * Declare a runtime selectable PCI API
 *
 * In the common case of a non-runtime-selectable PCI I/O API, allow
 * the runtime API code to be garbage-collected at link time to save
 * space.
 */
#ifdef PCIAPI_CLOUD
#define __pci_api( priority ) __table_entry ( PCI_APIS, priority )
#else
#define __pci_api( priority )
#endif

/* PCI runtime selectable API priorities */
#define PCIAPI_PRIORITY_EFI     01      /**< EFI PCI I/O protocols */
#define PCIAPI_PRIORITY_ECAM    02      /**< ACPI ECAM */
#define PCIAPI_PRIORITY_PCBIOS  03      /**< PCI BIOS calls */
#define PCIAPI_PRIORITY_DIRECT  04      /**< Direct Type 1 accesses */

/** Provide a runtime selectable PCI I/O API */
#define PROVIDE_PCIAPI_RUNTIME( subsys, priority )                         \
        struct pci_api pciapi_ ## subsys __pci_api ( priority ) = {        \
                .name = #subsys,                                           \
                .pci_can_probe = PCIAPI_INLINE ( subsys, pci_can_probe ),  \
                .pci_discover = PCIAPI_INLINE ( subsys, pci_discover ),    \
                .pci_read_config_byte =                                    \
                        PCIAPI_INLINE ( subsys, pci_read_config_byte ),    \
                .pci_read_config_word =                                    \
                        PCIAPI_INLINE ( subsys, pci_read_config_word ),    \
                .pci_read_config_dword =                                   \
                        PCIAPI_INLINE ( subsys, pci_read_config_dword ),   \
                .pci_write_config_byte =                                   \
                        PCIAPI_INLINE ( subsys, pci_write_config_byte ),   \
                .pci_write_config_word =                                   \
                        PCIAPI_INLINE ( subsys, pci_write_config_word ),   \
                .pci_write_config_dword =                                  \
                        PCIAPI_INLINE ( subsys, pci_write_config_dword ),  \
                .pci_ioremap = PCIAPI_INLINE ( subsys, pci_ioremap ),      \
        }

#endif /* _IPXE_PCI_IO_H */