diff options
Diffstat (limited to 'drivers/acpi/acpica/hwregs.c')
| -rw-r--r-- | drivers/acpi/acpica/hwregs.c | 155 |
1 files changed, 110 insertions, 45 deletions
diff --git a/drivers/acpi/acpica/hwregs.c b/drivers/acpi/acpica/hwregs.c index 3b7fb99362b6..de74a4c25085 100644 --- a/drivers/acpi/acpica/hwregs.c +++ b/drivers/acpi/acpica/hwregs.c @@ -6,7 +6,7 @@ ******************************************************************************/ /* - * Copyright (C) 2000 - 2016, Intel Corp. + * Copyright (C) 2000 - 2017, Intel Corp. * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -52,7 +52,8 @@ ACPI_MODULE_NAME("hwregs") #if (!ACPI_REDUCED_HARDWARE) /* Local Prototypes */ static u8 -acpi_hw_get_access_bit_width(struct acpi_generic_address *reg, +acpi_hw_get_access_bit_width(u64 address, + struct acpi_generic_address *reg, u8 max_bit_width); static acpi_status @@ -71,7 +72,8 @@ acpi_hw_write_multiple(u32 value, * * FUNCTION: acpi_hw_get_access_bit_width * - * PARAMETERS: reg - GAS register structure + * PARAMETERS: address - GAS register address + * reg - GAS register structure * max_bit_width - Max bit_width supported (32 or 64) * * RETURN: Status @@ -81,27 +83,59 @@ acpi_hw_write_multiple(u32 value, ******************************************************************************/ static u8 -acpi_hw_get_access_bit_width(struct acpi_generic_address *reg, u8 max_bit_width) +acpi_hw_get_access_bit_width(u64 address, + struct acpi_generic_address *reg, u8 max_bit_width) { - if (!reg->access_width) { - if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) { - max_bit_width = 32; - } + u8 access_bit_width; - /* - * Detect old register descriptors where only the bit_width field - * makes senses. - */ - if (reg->bit_width < max_bit_width && - !reg->bit_offset && reg->bit_width && - ACPI_IS_POWER_OF_TWO(reg->bit_width) && - ACPI_IS_ALIGNED(reg->bit_width, 8)) { - return (reg->bit_width); - } - return (max_bit_width); + /* + * GAS format "register", used by FADT: + * 1. Detected if bit_offset is 0 and bit_width is 8/16/32/64; + * 2. access_size field is ignored and bit_width field is used for + * determining the boundary of the IO accesses. + * GAS format "region", used by APEI registers: + * 1. Detected if bit_offset is not 0 or bit_width is not 8/16/32/64; + * 2. access_size field is used for determining the boundary of the + * IO accesses; + * 3. bit_offset/bit_width fields are used to describe the "region". + * + * Note: This algorithm assumes that the "Address" fields should always + * contain aligned values. + */ + if (!reg->bit_offset && reg->bit_width && + ACPI_IS_POWER_OF_TWO(reg->bit_width) && + ACPI_IS_ALIGNED(reg->bit_width, 8)) { + access_bit_width = reg->bit_width; + } else if (reg->access_width) { + access_bit_width = (1 << (reg->access_width + 2)); } else { - return (1 << (reg->access_width + 2)); + access_bit_width = + ACPI_ROUND_UP_POWER_OF_TWO_8(reg->bit_offset + + reg->bit_width); + if (access_bit_width <= 8) { + access_bit_width = 8; + } else { + while (!ACPI_IS_ALIGNED(address, access_bit_width >> 3)) { + access_bit_width >>= 1; + } + } } + + /* Maximum IO port access bit width is 32 */ + + if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) { + max_bit_width = 32; + } + + /* + * Return access width according to the requested maximum access bit width, + * as the caller should know the format of the register and may enforce + * a 32-bit accesses. + */ + if (access_bit_width < max_bit_width) { + return (access_bit_width); + } + return (max_bit_width); } /****************************************************************************** @@ -163,7 +197,8 @@ acpi_hw_validate_register(struct acpi_generic_address *reg, /* Validate the bit_width, convert access_width into number of bits */ - access_width = acpi_hw_get_access_bit_width(reg, max_bit_width); + access_width = + acpi_hw_get_access_bit_width(*address, reg, max_bit_width); bit_width = ACPI_ROUND_UP(reg->bit_offset + reg->bit_width, access_width); if (max_bit_width < bit_width) { @@ -219,7 +254,7 @@ acpi_status acpi_hw_read(u32 *value, struct acpi_generic_address *reg) * into number of bits based */ *value = 0; - access_width = acpi_hw_get_access_bit_width(reg, 32); + access_width = acpi_hw_get_access_bit_width(address, reg, 32); bit_width = reg->bit_offset + reg->bit_width; bit_offset = reg->bit_offset; @@ -252,20 +287,6 @@ acpi_status acpi_hw_read(u32 *value, struct acpi_generic_address *reg) &value32, access_width); } - - /* - * Use offset style bit masks because: - * bit_offset < access_width/bit_width < access_width, and - * access_width is ensured to be less than 32-bits by - * acpi_hw_validate_register(). - */ - if (bit_offset) { - value32 &= ACPI_MASK_BITS_BELOW(bit_offset); - bit_offset = 0; - } - if (bit_width < access_width) { - value32 &= ACPI_MASK_BITS_ABOVE(bit_width); - } } /* @@ -306,6 +327,12 @@ acpi_status acpi_hw_read(u32 *value, struct acpi_generic_address *reg) acpi_status acpi_hw_write(u32 value, struct acpi_generic_address *reg) { u64 address; + u8 access_width; + u32 bit_width; + u8 bit_offset; + u64 value64; + u32 value32; + u8 index; acpi_status status; ACPI_FUNCTION_NAME(hw_write); @@ -317,23 +344,61 @@ acpi_status acpi_hw_write(u32 value, struct acpi_generic_address *reg) return (status); } + /* Convert access_width into number of bits based */ + + access_width = acpi_hw_get_access_bit_width(address, reg, 32); + bit_width = reg->bit_offset + reg->bit_width; + bit_offset = reg->bit_offset; + /* * Two address spaces supported: Memory or IO. PCI_Config is * not supported here because the GAS structure is insufficient */ - if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) { - status = acpi_os_write_memory((acpi_physical_address) - address, (u64)value, - reg->bit_width); - } else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */ - - status = acpi_hw_write_port((acpi_io_address) - address, value, reg->bit_width); + index = 0; + while (bit_width) { + /* + * Use offset style bit reads because "Index * AccessWidth" is + * ensured to be less than 32-bits by acpi_hw_validate_register(). + */ + value32 = ACPI_GET_BITS(&value, index * access_width, + ACPI_MASK_BITS_ABOVE_32(access_width)); + + if (bit_offset >= access_width) { + bit_offset -= access_width; + } else { + if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) { + value64 = (u64)value32; + status = + acpi_os_write_memory((acpi_physical_address) + address + + index * + ACPI_DIV_8 + (access_width), + value64, access_width); + } else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */ + + status = acpi_hw_write_port((acpi_io_address) + address + + index * + ACPI_DIV_8 + (access_width), + value32, + access_width); + } + } + + /* + * Index * access_width is ensured to be less than 32-bits by + * acpi_hw_validate_register(). + */ + bit_width -= + bit_width > access_width ? access_width : bit_width; + index++; } ACPI_DEBUG_PRINT((ACPI_DB_IO, "Wrote: %8.8X width %2d to %8.8X%8.8X (%s)\n", - value, reg->bit_width, ACPI_FORMAT_UINT64(address), + value, access_width, ACPI_FORMAT_UINT64(address), acpi_ut_get_region_name(reg->space_id))); return (status); |