/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* PCI Support when Configuration Space is in I/O
*/
/*
* COPYRIGHT (c) 2016.
* On-Line Applications Research Corporation (OAR).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <rtems.h>
#include <bsp.h>
#include <bsp/bspimpl.h>
static int pci_io_initialized = 0;
/*
* Forward reference. Initialized at bottom.
*/
static const pci_config_access_functions pci_io_indirect_functions;
/*
* Detects presense of PCI Configuration is in I/O space. If so, return
* pointer to accessor methods.
*
* NOTE: TBD to determine if (a) PCI Bus exists and (b) this is the
* access method.
*/
const pci_config_access_functions *pci_io_initialize(void)
{
pci_io_initialized = 1;
printk( "PCI I/O Support Initialized\n" );
return &pci_io_indirect_functions;
}
/*
* Build PCI Address
*/
static inline uint32_t pci_io_build_address(
uint16_t bus,
uint16_t slot,
uint16_t function,
uint16_t offset
)
{
uint32_t bus_u32 = (uint32_t)bus;
uint32_t slot_u32 = (uint32_t)slot;
uint32_t function_u32 = (uint32_t)function;
uint32_t address;
/*
* create configuration address as per figure at
* http://wiki.osdev.org/PCI#Configuration_Space_Access_Mechanism_.231
*/
address = (uint32_t) 0x80000000; /* Bit 31 - Enable Bit */
/* Bits 30-24 - Reserved */
address |= bus_u32 << 16; /* Bits 23-16 - Bus Number */
address |= slot_u32 << 11; /* Bits 15-11 - Device/Slot Number */
address |= function_u32 << 8; /* Bits 10-8 - Function Number */
address |= offset & 0xfc; /* Bits 7-2 - Offset/Register Number */
/* Bits 1-0 - Reserved 0 */
return address;
}
static int BSP_pci_read_config_byte(
unsigned char bus,
unsigned char slot,
unsigned char function,
unsigned char offset,
unsigned char *value
)
{
uint32_t address;
uint32_t tmp;
address = pci_io_build_address( bus, slot, function, offset );
/* write out the address */
outport_long(0xCF8, address);
/* read in the data */
inport_long(0xCFC, tmp);
/* (offset & 3) * 8) = 0 will choose the first byte of the 32 bits register */
*value = (uint16_t)(tmp >> ((offset & 3) * 8)) & 0xff;
return PCIBIOS_SUCCESSFUL;
}
static int BSP_pci_read_config_word(
unsigned char bus,
unsigned char slot,
unsigned char function,
unsigned char offset,
unsigned short *value
)
{
uint32_t address;
uint32_t tmp;
address = pci_io_build_address( bus, slot, function, offset );
/* write out the address */
outport_long(0xCF8, address);
/* read in the data */
inport_long(0xCFC, tmp);
/* (offset & 2) * 8) = 0 will choose the first word of the 32 bits register */
*value = (uint16_t)(tmp >> ((offset & 2) * 8)) & 0xffff;
return PCIBIOS_SUCCESSFUL;
}
static int BSP_pci_read_config_dword(
unsigned char bus,
unsigned char slot,
unsigned char function,
unsigned char offset,
uint32_t *value
)
{
uint32_t address;
uint32_t tmp;
address = pci_io_build_address( bus, slot, function, offset );
/* write out the address */
outport_long(0xCF8, address);
/* read in the data */
inport_long(0xCFC, tmp);
*value = tmp;
return PCIBIOS_SUCCESSFUL;
}
static int BSP_pci_write_config_byte(
unsigned char bus,
unsigned char slot,
unsigned char function,
unsigned char offset,
unsigned char value
)
{
uint32_t address;
address = pci_io_build_address( bus, slot, function, offset );
/* write out the address */
outport_long(0xCF8, address);
/* read in the data */
outport_byte(0xCFC, value);
return PCIBIOS_SUCCESSFUL;
}
static int BSP_pci_write_config_word(
unsigned char bus,
unsigned char slot,
unsigned char function,
unsigned char offset,
unsigned short value
)
{
uint32_t address;
address = pci_io_build_address( bus, slot, function, offset );
/* write out the address */
outport_long(0xCF8, address);
/* read in the data */
outport_word(0xCFC, value);
return PCIBIOS_SUCCESSFUL;
}
static int BSP_pci_write_config_dword(
unsigned char bus,
unsigned char slot,
unsigned char function,
unsigned char offset,
uint32_t value
)
{
uint32_t address;
address = pci_io_build_address( bus, slot, function, offset );
/* write out the address */
outport_long(0xCF8, address);
/* read in the data */
outport_long(0xCFC, value);
return PCIBIOS_SUCCESSFUL;
}
static const pci_config_access_functions pci_io_indirect_functions = {
BSP_pci_read_config_byte,
BSP_pci_read_config_word,
BSP_pci_read_config_dword,
BSP_pci_write_config_byte,
BSP_pci_write_config_word,
BSP_pci_write_config_dword
};
