// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: hwvalid - I/O request validation
*
* Copyright (C) 2000 - 2025, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#define _COMPONENT ACPI_HARDWARE
ACPI_MODULE_NAME(
"hwvalid")
/* Local prototypes */
static acpi_status
acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width);
/*
* Protected I/O ports. Some ports are always illegal, and some are
* conditionally illegal. This table must remain ordered by port address.
*
* The table is used to implement the Microsoft port access rules that
* first appeared in Windows XP. Some ports are always illegal, and some
* ports are only illegal if the BIOS calls _OSI with nothing newer than
* the specific _OSI strings.
*
* This provides ACPICA with the desired port protections and
* Microsoft compatibility.
*
* Description of port entries:
* DMA: DMA controller
* PIC0: Programmable Interrupt Controller (8259A)
* PIT1: System Timer 1
* PIT2: System Timer 2 failsafe
* RTC: Real-time clock
* CMOS: Extended CMOS
* DMA1: DMA 1 page registers
* DMA1L: DMA 1 Ch 0 low page
* DMA2: DMA 2 page registers
* DMA2L: DMA 2 low page refresh
* ARBC: Arbitration control
* SETUP: Reserved system board setup
* POS: POS channel select
* PIC1: Cascaded PIC
* IDMA: ISA DMA
* ELCR: PIC edge/level registers
* PCI: PCI configuration space
*/
static const struct acpi_port_info acpi_protected_ports[] = {
{
"DMA", 0x0000, 0x000F, ACPI_OSI_WIN_XP},
{
"PIC0", 0x0020, 0x0021, ACPI_ALWAYS_ILLEGAL},
{
"PIT1", 0x0040, 0x0043, ACPI_OSI_WIN_XP},
{
"PIT2", 0x0048, 0x004B, ACPI_OSI_WIN_XP},
{
"RTC", 0x0070, 0x0071, ACPI_OSI_WIN_XP},
{
"CMOS", 0x0074, 0x0076, ACPI_OSI_WIN_XP},
{
"DMA1", 0x0081, 0x0083, ACPI_OSI_WIN_XP},
{
"DMA1L", 0x0087, 0x0087, ACPI_OSI_WIN_XP},
{
"DMA2", 0x0089, 0x008B, ACPI_OSI_WIN_XP},
{
"DMA2L", 0x008F, 0x008F, ACPI_OSI_WIN_XP},
{
"ARBC", 0x0090, 0x0091, ACPI_OSI_WIN_XP},
{
"SETUP", 0x0093, 0x0094, ACPI_OSI_WIN_XP},
{
"POS", 0x0096, 0x0097, ACPI_OSI_WIN_XP},
{
"PIC1", 0x00A0, 0x00A1, ACPI_ALWAYS_ILLEGAL},
{
"IDMA", 0x00C0, 0x00DF, ACPI_OSI_WIN_XP},
{
"ELCR", 0x04D0, 0x04D1, ACPI_ALWAYS_ILLEGAL},
{
"PCI", 0x0CF8, 0x0CFF, ACPI_OSI_WIN_XP}
};
#define ACPI_PORT_INFO_ENTRIES ACPI_ARRAY_LENGTH (acpi_protected_ports)
/******************************************************************************
*
* FUNCTION: acpi_hw_validate_io_request
*
* PARAMETERS: Address Address of I/O port/register
* bit_width Number of bits (8,16,32)
*
* RETURN: Status
*
* DESCRIPTION: Validates an I/O request (address/length). Certain ports are
* always illegal and some ports are only illegal depending on
* the requests the BIOS AML code makes to the predefined
* _OSI method.
*
******************************************************************************/
static acpi_status
acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width)
{
u32 i;
u32 byte_width;
acpi_io_address last_address;
const struct acpi_port_info *port_info;
ACPI_FUNCTION_TRACE(hw_validate_io_request);
/* Supported widths are 8/16/32 */
if ((bit_width != 8) && (bit_width != 16) && (bit_width != 32)) {
ACPI_ERROR((AE_INFO,
"Bad BitWidth parameter: %8.8X", bit_width));
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
port_info = acpi_protected_ports;
byte_width = ACPI_DIV_8(bit_width);
last_address = address + byte_width - 1;
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"Address %8.8X%8.8X LastAddress %8.8X%8.8X Length %X",
ACPI_FORMAT_UINT64(address),
ACPI_FORMAT_UINT64(last_address), byte_width));
/* Maximum 16-bit address in I/O space */
if (last_address > ACPI_UINT16_MAX) {
ACPI_ERROR((AE_INFO,
"Illegal I/O port address/length above 64K: %8.8X%8.8X/0x%X",
ACPI_FORMAT_UINT64(address), byte_width));
return_ACPI_STATUS(AE_LIMIT);
}
/* Exit if requested address is not within the protected port table */
if (address > acpi_protected_ports[ACPI_PORT_INFO_ENTRIES - 1].end) {
return_ACPI_STATUS(AE_OK);
}
/* Check request against the list of protected I/O ports */
for (i = 0; i < ACPI_PORT_INFO_ENTRIES; i++, port_info++) {
/*
* Check if the requested address range will write to a reserved
* port. There are four cases to consider:
*
* 1) Address range is contained completely in the port address range
* 2) Address range overlaps port range at the port range start
* 3) Address range overlaps port range at the port range end
* 4) Address range completely encompasses the port range
*/
if ((address <= port_info->end)
&& (last_address >= port_info->start)) {
/* Port illegality may depend on the _OSI calls made by the BIOS */
if (port_info->osi_dependency == ACPI_ALWAYS_ILLEGAL ||
acpi_gbl_osi_data == port_info->osi_dependency) {
ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
"Denied AML access to port 0x%8.8X%8.8X/%X (%s 0x%.4X-0x%.4X)\n",
ACPI_FORMAT_UINT64(address),
byte_width, port_info->name,
port_info->start,
port_info->end));
return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
}
}
/* Finished if address range ends before the end of this port */
if (last_address <= port_info->end) {
break;
}
}
return_ACPI_STATUS(AE_OK);
}
/******************************************************************************
*
* FUNCTION: acpi_hw_read_port
*
* PARAMETERS: Address Address of I/O port/register to read
* Value Where value (data) is returned
* Width Number of bits
*
* RETURN: Status and value read from port
*
* DESCRIPTION: Read data from an I/O port or register. This is a front-end
* to acpi_os_read_port that performs validation on both the port
* address and the length.
*
*****************************************************************************/
acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
{
acpi_status status;
u32 one_byte;
u32 i;
/* Truncate address to 16 bits if requested */
if (acpi_gbl_truncate_io_addresses) {
address &= ACPI_UINT16_MAX;
}
/* Validate the entire request and perform the I/O */
status = acpi_hw_validate_io_request(address, width);
if (ACPI_SUCCESS(status)) {
status = acpi_os_read_port(address, value, width);
return (status);
}
if (status != AE_AML_ILLEGAL_ADDRESS) {
return (status);
}
/*
* There has been a protection violation within the request. Fall
* back to byte granularity port I/O and ignore the failing bytes.
* This provides compatibility with other ACPI implementations.
*/
for (i = 0, *value = 0; i < width; i += 8) {
/* Validate and read one byte */
if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
status = acpi_os_read_port(address, &one_byte, 8);
if (ACPI_FAILURE(status)) {
return (status);
}
*value |= (one_byte << i);
}
address++;
}
return (AE_OK);
}
/******************************************************************************
*
* FUNCTION: acpi_hw_write_port
*
* PARAMETERS: Address Address of I/O port/register to write
* Value Value to write
* Width Number of bits
*
* RETURN: Status
*
* DESCRIPTION: Write data to an I/O port or register. This is a front-end
* to acpi_os_write_port that performs validation on both the port
* address and the length.
*
*****************************************************************************/
acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
{
acpi_status status;
u32 i;
/* Truncate address to 16 bits if requested */
if (acpi_gbl_truncate_io_addresses) {
address &= ACPI_UINT16_MAX;
}
/* Validate the entire request and perform the I/O */
status = acpi_hw_validate_io_request(address, width);
if (ACPI_SUCCESS(status)) {
status = acpi_os_write_port(address, value, width);
return (status);
}
if (status != AE_AML_ILLEGAL_ADDRESS) {
return (status);
}
/*
* There has been a protection violation within the request. Fall
* back to byte granularity port I/O and ignore the failing bytes.
* This provides compatibility with other ACPI implementations.
*/
for (i = 0; i < width; i += 8) {
/* Validate and write one byte */
if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
status =
acpi_os_write_port(address, (value >> i) & 0xFF, 8);
if (ACPI_FAILURE(status)) {
return (status);
}
}
address++;
}
return (AE_OK);
}
/******************************************************************************
*
* FUNCTION: acpi_hw_validate_io_block
*
* PARAMETERS: Address Address of I/O port/register blobk
* bit_width Number of bits (8,16,32) in each register
* count Number of registers in the block
*
* RETURN: Status
*
* DESCRIPTION: Validates a block of I/O ports/registers.
*
******************************************************************************/
acpi_status acpi_hw_validate_io_block(u64 address, u32 bit_width, u32 count)
{
acpi_status status;
while (count--) {
status = acpi_hw_validate_io_request((acpi_io_address)address,
bit_width);
if (ACPI_FAILURE(status))
return_ACPI_STATUS(status);
address += ACPI_DIV_8(bit_width);
}
return_ACPI_STATUS(AE_OK);
}
