diff options
Diffstat (limited to 'drivers/acpi/acpica/exregion.c')
-rw-r--r-- | drivers/acpi/acpica/exregion.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/drivers/acpi/acpica/exregion.c b/drivers/acpi/acpica/exregion.c index 1f1ce0c3d2f8..182abaf045e1 100644 --- a/drivers/acpi/acpica/exregion.c +++ b/drivers/acpi/acpica/exregion.c @@ -1,4 +1,3 @@ - /****************************************************************************** * * Module Name: exregion - ACPI default op_region (address space) handlers @@ -6,7 +5,7 @@ *****************************************************************************/ /* - * Copyright (C) 2000 - 2012, Intel Corp. + * Copyright (C) 2000 - 2013, Intel Corp. * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -143,9 +142,9 @@ acpi_ex_system_memory_space_handler(u32 function, } /* - * Attempt to map from the requested address to the end of the region. - * However, we will never map more than one page, nor will we cross - * a page boundary. + * October 2009: Attempt to map from the requested address to the + * end of the region. However, we will never map more than one + * page, nor will we cross a page boundary. */ map_length = (acpi_size) ((mem_info->address + mem_info->length) - address); @@ -155,12 +154,15 @@ acpi_ex_system_memory_space_handler(u32 function, * a page boundary, just map up to the page boundary, do not cross. * On some systems, crossing a page boundary while mapping regions * can cause warnings if the pages have different attributes - * due to resource management + * due to resource management. + * + * This has the added benefit of constraining a single mapping to + * one page, which is similar to the original code that used a 4k + * maximum window. */ page_boundary_map_length = ACPI_ROUND_UP(address, ACPI_DEFAULT_PAGE_SIZE) - address; - - if (!page_boundary_map_length) { + if (page_boundary_map_length == 0) { page_boundary_map_length = ACPI_DEFAULT_PAGE_SIZE; } @@ -202,7 +204,7 @@ acpi_ex_system_memory_space_handler(u32 function, * Perform the memory read or write * * Note: For machines that do not support non-aligned transfers, the target - * address was checked for alignment above. We do not attempt to break the + * address was checked for alignment above. We do not attempt to break the * transfer up into smaller (byte-size) chunks because the AML specifically * asked for a transfer width that the hardware may require. */ @@ -237,19 +239,19 @@ acpi_ex_system_memory_space_handler(u32 function, switch (bit_width) { case 8: - ACPI_SET8(logical_addr_ptr) = (u8) * value; + ACPI_SET8(logical_addr_ptr, *value); break; case 16: - ACPI_SET16(logical_addr_ptr) = (u16) * value; + ACPI_SET16(logical_addr_ptr, *value); break; case 32: - ACPI_SET32(logical_addr_ptr) = (u32) * value; + ACPI_SET32(logical_addr_ptr, *value); break; case 64: - ACPI_SET64(logical_addr_ptr) = (u64) * value; + ACPI_SET64(logical_addr_ptr, *value); break; default: |