summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/acpica/hwregs.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/acpica/hwregs.c')
-rw-r--r--drivers/acpi/acpica/hwregs.c291
1 files changed, 259 insertions, 32 deletions
diff --git a/drivers/acpi/acpica/hwregs.c b/drivers/acpi/acpica/hwregs.c
index 5ba0498412fd..0f18dbc9a37f 100644
--- a/drivers/acpi/acpica/hwregs.c
+++ b/drivers/acpi/acpica/hwregs.c
@@ -51,6 +51,10 @@ ACPI_MODULE_NAME("hwregs")
#if (!ACPI_REDUCED_HARDWARE)
/* Local Prototypes */
+static u8
+acpi_hw_get_access_bit_width(struct acpi_generic_address *reg,
+ u8 max_bit_width);
+
static acpi_status
acpi_hw_read_multiple(u32 *value,
struct acpi_generic_address *register_a,
@@ -65,6 +69,48 @@ acpi_hw_write_multiple(u32 value,
/******************************************************************************
*
+ * FUNCTION: acpi_hw_get_access_bit_width
+ *
+ * PARAMETERS: reg - GAS register structure
+ * max_bit_width - Max bit_width supported (32 or 64)
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Obtain optimal access bit width
+ *
+ ******************************************************************************/
+
+static u8
+acpi_hw_get_access_bit_width(struct acpi_generic_address *reg, u8 max_bit_width)
+{
+ u64 address;
+
+ if (!reg->access_width) {
+ /*
+ * Detect old register descriptors where only the bit_width field
+ * makes senses. The target address is copied to handle possible
+ * alignment issues.
+ */
+ ACPI_MOVE_64_TO_64(&address, &reg->address);
+ if (!reg->bit_offset && reg->bit_width &&
+ ACPI_IS_POWER_OF_TWO(reg->bit_width) &&
+ ACPI_IS_ALIGNED(reg->bit_width, 8) &&
+ ACPI_IS_ALIGNED(address, reg->bit_width)) {
+ return (reg->bit_width);
+ } else {
+ if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
+ return (32);
+ } else {
+ return (max_bit_width);
+ }
+ }
+ } else {
+ return (1 << (reg->access_width + 2));
+ }
+}
+
+/******************************************************************************
+ *
* FUNCTION: acpi_hw_validate_register
*
* PARAMETERS: reg - GAS register structure
@@ -83,6 +129,8 @@ acpi_status
acpi_hw_validate_register(struct acpi_generic_address *reg,
u8 max_bit_width, u64 *address)
{
+ u8 bit_width;
+ u8 access_width;
/* Must have a valid pointer to a GAS structure */
@@ -109,23 +157,25 @@ acpi_hw_validate_register(struct acpi_generic_address *reg,
return (AE_SUPPORT);
}
- /* Validate the bit_width */
+ /* Validate the access_width */
- if ((reg->bit_width != 8) &&
- (reg->bit_width != 16) &&
- (reg->bit_width != 32) && (reg->bit_width != max_bit_width)) {
+ if (reg->access_width > 4) {
ACPI_ERROR((AE_INFO,
- "Unsupported register bit width: 0x%X",
- reg->bit_width));
+ "Unsupported register access width: 0x%X",
+ reg->access_width));
return (AE_SUPPORT);
}
- /* Validate the bit_offset. Just a warning for now. */
+ /* Validate the bit_width, convert access_width into number of bits */
- if (reg->bit_offset != 0) {
+ access_width = acpi_hw_get_access_bit_width(reg, max_bit_width);
+ bit_width =
+ ACPI_ROUND_UP(reg->bit_offset + reg->bit_width, access_width);
+ if (max_bit_width < bit_width) {
ACPI_WARNING((AE_INFO,
- "Unsupported register bit offset: 0x%X",
- reg->bit_offset));
+ "Requested bit width 0x%X is smaller than register bit width 0x%X",
+ max_bit_width, bit_width));
+ return (AE_SUPPORT);
}
return (AE_OK);
@@ -145,17 +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);
@@ -167,28 +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 */
+
+ status = acpi_hw_read_port((acpi_io_address)
+ address +
+ index *
+ ACPI_DIV_8
+ (access_width),
+ &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);
+ }
+ }
- *value = (u32)value64;
- } else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
+ /*
+ * 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);
- status = acpi_hw_read_port((acpi_io_address)
- address, value, reg->bit_width);
+ 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);
@@ -212,6 +311,12 @@ 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 new_value32, old_value32;
+ u8 index;
acpi_status status;
ACPI_FUNCTION_NAME(hw_write);
@@ -223,23 +328,145 @@ 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(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().
+ */
+ new_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 {
+ /*
+ * Use offset style bit masks because access_width is ensured
+ * to be less than 32-bits by acpi_hw_validate_register() and
+ * bit_offset/bit_width is less than access_width here.
+ */
+ if (bit_offset) {
+ new_value32 &= ACPI_MASK_BITS_BELOW(bit_offset);
+ }
+ if (bit_width < access_width) {
+ new_value32 &= ACPI_MASK_BITS_ABOVE(bit_width);
+ }
+
+ if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
+ if (bit_offset || bit_width < access_width) {
+ /*
+ * Read old values in order not to modify the bits that
+ * are beyond the register bit_width/bit_offset setting.
+ */
+ status =
+ acpi_os_read_memory((acpi_physical_address)
+ address +
+ index *
+ ACPI_DIV_8
+ (access_width),
+ &value64,
+ access_width);
+ old_value32 = (u32)value64;
+
+ /*
+ * Use offset style bit masks because access_width is
+ * ensured to be less than 32-bits by
+ * acpi_hw_validate_register() and bit_offset/bit_width is
+ * less than access_width here.
+ */
+ if (bit_offset) {
+ old_value32 &=
+ ACPI_MASK_BITS_ABOVE
+ (bit_offset);
+ bit_offset = 0;
+ }
+ if (bit_width < access_width) {
+ old_value32 &=
+ ACPI_MASK_BITS_BELOW
+ (bit_width);
+ }
+
+ new_value32 |= old_value32;
+ }
+
+ value64 = (u64)new_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 */
+
+ if (bit_offset || bit_width < access_width) {
+ /*
+ * Read old values in order not to modify the bits that
+ * are beyond the register bit_width/bit_offset setting.
+ */
+ status =
+ acpi_hw_read_port((acpi_io_address)
+ address +
+ index *
+ ACPI_DIV_8
+ (access_width),
+ &old_value32,
+ access_width);
+
+ /*
+ * Use offset style bit masks because access_width is
+ * ensured to be less than 32-bits by
+ * acpi_hw_validate_register() and bit_offset/bit_width is
+ * less than access_width here.
+ */
+ if (bit_offset) {
+ old_value32 &=
+ ACPI_MASK_BITS_ABOVE
+ (bit_offset);
+ bit_offset = 0;
+ }
+ if (bit_width < access_width) {
+ old_value32 &=
+ ACPI_MASK_BITS_BELOW
+ (bit_width);
+ }
+
+ new_value32 |= old_value32;
+ }
+
+ status = acpi_hw_write_port((acpi_io_address)
+ address +
+ index *
+ ACPI_DIV_8
+ (access_width),
+ new_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 (git 2.39.1) at 2024-12-13 09:41:29 +0100