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Commit a65131e9 authored by Lin Ming's avatar Lin Ming Committed by Len Brown
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I/O port protection: update for windows compatibility. 

For windows compatibility,
1) On a port protection violation, simply ignore the request and
   do not return an exception (allow the control method to continue execution.)
2) If only part of the request overlaps a protected port,
   read/write the individual ports that are not protected.

http://bugzilla.kernel.org/show_bug.cgi?id=13036



Signed-off-by: default avatarLin Ming <ming.m.lin@intel.com>
Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 09106974

drivers/acpi/acpica/hwvalid.c

+71 −14
Original line number Diff line number Diff line
@@ -151,7 +151,7 @@ acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width) 
		ACPI_ERROR((AE_INFO,

			    "Illegal I/O port address/length above 64K: 0x%p/%X",

			    ACPI_CAST_PTR(void, address), byte_width));

		return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);

		return_ACPI_STATUS(AE_LIMIT);

	}



	/* Exit if requested address is not within the protected port table */
@@ -178,11 +178,12 @@ acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width) 
			/* Port illegality may depend on the _OSI calls made by the BIOS */



			if (acpi_gbl_osi_data >= port_info->osi_dependency) {

				ACPI_ERROR((AE_INFO,

				ACPI_DEBUG_PRINT((ACPI_DB_IO,

						  "Denied AML access to port 0x%p/%X (%s 0x%.4X-0x%.4X)",

						  ACPI_CAST_PTR(void, address),

						  byte_width, port_info->name,

					    port_info->start, port_info->end));

						  port_info->start,

						  port_info->end));



				return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);

			}
@@ -206,7 +207,7 @@ acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width) 
 *              Value               Where value is placed

 *              Width               Number of bits

 *

 * RETURN:      Value read from port

 * 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
@@ -217,16 +218,45 @@ acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width) 
acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)

{

	acpi_status status;

	u32 one_byte;

	u32 i;



	/* Validate the entire request and perform the I/O */



	status = acpi_hw_validate_io_request(address, width);

	if (ACPI_FAILURE(status)) {

	if (ACPI_SUCCESS(status)) {

		status = acpi_os_read_port(address, value, width);

		return status;

	}



	status = acpi_os_read_port(address, value, width);

	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 Windows compatibility.

	 */

	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
@@ -235,7 +265,7 @@ acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width) 
 *              Value               Value to write

 *              Width               Number of bits

 *

 * RETURN:      None

 * 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
@@ -246,12 +276,39 @@ acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width) 
acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)

{

	acpi_status status;

	u32 i;



	/* Validate the entire request and perform the I/O */



	status = acpi_hw_validate_io_request(address, width);

	if (ACPI_FAILURE(status)) {

	if (ACPI_SUCCESS(status)) {

		status = acpi_os_write_port(address, value, width);

		return status;

	}



	status = acpi_os_write_port(address, value, width);

	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 Windows compatibility.

	 */

	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;

}