Pci.c File Reference

Routines for interacting with PCI(e) fabric. More...

#include "pch.h"

Functions
QWORD	PciReadCam (WORD Bus, WORD Device, WORD Function, BYTE Offset, UINT8 Width)
	Read from PCI configuration space (CAM) at given offset.
BOOLEAN	PciWriteCam (WORD Bus, WORD Device, WORD Function, BYTE Offset, UINT8 Width, QWORD Value)
	Write to PCI configuration space (CAM) at given offset.

Detailed Description

Routines for interacting with PCI(e) fabric.

Headers related to interacting with PCI(e) fabric.

Author

Björn Ruytenberg (bjorn.nosp@m.@bjo.nosp@m.rnweb.nosp@m..nl)

Version

0.10.3

Date

2024-11-11

Copyright

This project is released under the GNU Public License v3.

Function Documentation

PciReadCam()

QWORD PciReadCam	(	WORD	Bus,
		WORD	Device,
		WORD	Function,
		BYTE	Offset,
		UINT8	Width )

Read from PCI configuration space (CAM) at given offset.

Parameters

Bus
Device
Function
Offset
Width	Number of bytes to return. Supported data types: BYTE (1), WORD (2), DWORD (4), QWORD (8).

Returns

QWORD

{
    WORD Target = 0;
 
    //
    // Restrict Offset to CAM address space; restrict BDF to our internal limits
    //
    if (Offset > CAM_CONFIG_SPACE_LENGTH ||
        Bus >= BUS_MAX_NUM ||
        Device >= DEVICE_MAX_NUM ||
        Function >= FUNCTION_MAX_NUM)
    {
        return MAXDWORD64;
    }
 
    Target = Function + ((Device & 0x1F) << 3) + ((Bus & 0xFF) << 8);
    _outpd(CFGADR, (DWORD)(Target << 8) | 0x80000000UL | ((DWORD)Offset & ~3));
 
    switch ((UINT32)Width)
    {
    case sizeof(BYTE):
        return (BYTE)_inp(CFGDAT + (Offset & 0x3));
        break;
    case sizeof(WORD):
        return (WORD)_inpw(CFGDAT + (Offset & 0x2));
        break;
    case sizeof(DWORD):
        return _inpd(CFGDAT);
        break;
    case sizeof(QWORD):
        return (PciReadCam(Bus, Device, Function, Offset + sizeof(DWORD), sizeof(DWORD)) << 32) | PciReadCam(Bus, Device, Function, Offset + 0, sizeof(DWORD));
        break;
    default:
        return MAXDWORD64;
    }
}

PciWriteCam()

BOOLEAN PciWriteCam	(	WORD	Bus,
		WORD	Device,
		WORD	Function,
		BYTE	Offset,
		UINT8	Width,
		QWORD	Value )

Write to PCI configuration space (CAM) at given offset.

Parameters

Bus
Device
Function
Offset
Width	Number of bytes to write. Supported data types: BYTE (1), WORD (2), DWORD (4), QWORD (8).
Value	to write.

Returns

BOOLEAN

{
    BOOLEAN Result = TRUE;
    WORD    Target = 0;
 
    //
    // Restrict Offset to CAM address space; restrict BDF to our internal limits
    //
    if (Offset > CAM_CONFIG_SPACE_LENGTH ||
        Bus >= BUS_MAX_NUM ||
        Device >= DEVICE_MAX_NUM ||
        Function >= FUNCTION_MAX_NUM)
    {
        Result = FALSE;
    }
    else
    {
        Target = Function + ((Device & 0x1F) << 3) + ((Bus & 0xFF) << 8);
        _outpd(CFGADR, (DWORD)(Target << 8) | 0x80000000UL | ((DWORD)Offset & ~3));
 
        switch ((UINT32)Width)
        {
        case sizeof(BYTE):
            _outp((CFGDAT + (Offset & 0x3)), (BYTE)Value);
            Result = TRUE;
            break;
        case sizeof(WORD):
            _outpw((CFGDAT + (Offset & 0x2)), (WORD)Value);
            Result = TRUE;
            break;
        case sizeof(DWORD):
            _outpd((CFGDAT + Offset), (DWORD)Value);
            Result = TRUE;
            break;
        case sizeof(QWORD):
            Result = PciWriteCam(Bus, Device, Function, Offset + sizeof(DWORD), sizeof(DWORD), (DWORD)(Value >> 32));
            Result = PciWriteCam(Bus, Device, Function, Offset + 0, sizeof(DWORD), (DWORD)Value);
            break;
        default:
            Result = FALSE;
        }
    }
 
    return Result;
}