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Diffstat (limited to 'drivers/acpi/acpica/hwregs.c')
-rw-r--r--drivers/acpi/acpica/hwregs.c155
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);
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-11-19 22:54:56 +0100