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ACPICA: ACPI 2.0, Hardware: Add access_width/bit_offset support in acpi_hw_read()

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ACPICA commit 96ece052d4d073aae4f935f0ff0746646aea1174
ACPICA commit 3d8583a054e410f2ea4d73b48986facad9cfc0d4

This patch adds access_width/bit_offset support in acpi_hw_read().
This also enables GAS definition where bit_width is not a power of
two. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/96ece052
Link: https://github.com/acpica/acpica/commit/3d8583a0
Link: https://bugs.acpica.org/show_bug.cgi?id=1240
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Lv Zheng 2016-05-05 12:58:52 +08:00 committed by Rafael J. Wysocki
parent 9222aa8234
commit c3bc26d4b4
1 changed files with 62 additions and 13 deletions
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75
drivers/acpi/acpica/hwregs.c
View File

@ -195,17 +195,19 @@ acpi_hw_validate_register(struct acpi_generic_address *reg,
* 64-bit values is not needed.
*
* LIMITATIONS: <These limitations also apply to acpi_hw_write>
* bit_width must be exactly 8, 16, or 32.
* space_ID must be system_memory or system_IO.
* bit_offset and access_width are currently ignored, as there has
* not been a need to implement these.
*
******************************************************************************/
acpi_status acpi_hw_read(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_read);
@ -217,28 +219,75 @@ acpi_status acpi_hw_read(u32 *value, struct acpi_generic_address *reg)
return (status);
}
/* Initialize entire 32-bit return value to zero */
/*
* Initialize entire 32-bit return value to zero, convert access_width
* into number of bits based
*/
*value = 0;
access_width = acpi_hw_get_access_bit_width(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_read_memory((acpi_physical_address)
address, &value64, reg->bit_width);
index = 0;
while (bit_width) {
if (bit_offset >= access_width) {
value32 = 0;
bit_offset -= access_width;
} else {
if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
status =
acpi_os_read_memory((acpi_physical_address)
address +
index *
ACPI_DIV_8
(access_width),
&value64, access_width);
value32 = (u32)value64;
} else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
*value = (u32)value64;
} else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
status = acpi_hw_read_port((acpi_io_address)
address +
index *
ACPI_DIV_8
(access_width),
&value32,
access_width);
}
status = acpi_hw_read_port((acpi_io_address)
address, value, reg->bit_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);
}
}
/*
* Use offset style bit writes because "Index * AccessWidth" is
* ensured to be less than 32-bits by acpi_hw_validate_register().
*/
ACPI_SET_BITS(value, index * access_width,
ACPI_MASK_BITS_ABOVE_32(access_width), value32);
bit_width -=
bit_width > access_width ? access_width : bit_width;
index++;
}
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"Read: %8.8X width %2d from %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);