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authorBob Moore <robert.moore@intel.com>2018-10-03 21:45:36 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2018-10-04 10:06:27 +0300
commite324e10109fc4fdd3a7d63cbc4114da978dce835 (patch)
treef1663ada0ca4763ac418a931ce7aca8bfb056500 /drivers/acpi/acpica/exfield.c
parentf8553720e103821504f86a2a21ffe4c188d47b2f (diff)
downloadlinux-e324e10109fc4fdd3a7d63cbc4114da978dce835.tar.xz
ACPICA: Update for field unit access
Mostly for access to Generic Serial Bus, but also cleanup for the other fields. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Erik Schmauss <erik.schmauss@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/acpica/exfield.c')
-rw-r--r--drivers/acpi/acpica/exfield.c712
1 files changed, 432 insertions, 280 deletions
diff --git a/drivers/acpi/acpica/exfield.c b/drivers/acpi/acpica/exfield.c
index 17b937c5144f..f3e5e988e219 100644
--- a/drivers/acpi/acpica/exfield.c
+++ b/drivers/acpi/acpica/exfield.c
@@ -1,7 +1,7 @@
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
- * Module Name: exfield - ACPI AML (p-code) execution - field manipulation
+ * Module Name: exfield - AML execution - field_unit read/write
*
* Copyright (C) 2000 - 2018, Intel Corp.
*
@@ -17,71 +17,80 @@
ACPI_MODULE_NAME("exfield")
/* Local prototypes */
-static u32
-acpi_ex_get_serial_access_length(u32 accessor_type, u32 access_length);
+static acpi_status
+acpi_ex_read_serial_bus(union acpi_operand_object *obj_desc,
+ union acpi_operand_object **return_buffer);
+
+static acpi_status
+acpi_ex_write_serial_bus(union acpi_operand_object *source_desc,
+ union acpi_operand_object *obj_desc,
+ union acpi_operand_object **return_buffer);
+
+static acpi_status
+acpi_ex_read_gpio(union acpi_operand_object *obj_desc, void *buffer);
+
+static acpi_status
+acpi_ex_write_gpio(union acpi_operand_object *source_desc,
+ union acpi_operand_object *obj_desc,
+ union acpi_operand_object **return_buffer);
+
+/*
+ * This table maps the various Attrib protocols to the byte transfer
+ * length. Used for the generic serial bus.
+ */
+#define ACPI_INVALID_PROTOCOL_ID 0x80
+#define ACPI_MAX_PROTOCOL_ID 0x0F
+
+const u8 acpi_protocol_lengths[] = {
+ ACPI_INVALID_PROTOCOL_ID, /* 0 - reserved */
+ ACPI_INVALID_PROTOCOL_ID, /* 1 - reserved */
+ 0x00, /* 2 - ATTRIB_QUICK */
+ ACPI_INVALID_PROTOCOL_ID, /* 3 - reserved */
+ 0x01, /* 4 - ATTRIB_SEND_RECEIVE */
+ ACPI_INVALID_PROTOCOL_ID, /* 5 - reserved */
+ 0x01, /* 6 - ATTRIB_BYTE */
+ ACPI_INVALID_PROTOCOL_ID, /* 7 - reserved */
+ 0x02, /* 8 - ATTRIB_WORD */
+ ACPI_INVALID_PROTOCOL_ID, /* 9 - reserved */
+ 0xFF, /* A - ATTRIB_BLOCK */
+ 0xFF, /* B - ATTRIB_BYTES */
+ 0x02, /* C - ATTRIB_PROCESS_CALL */
+ 0xFF, /* D - ATTRIB_BLOCK_PROCESS_CALL */
+ 0xFF, /* E - ATTRIB_RAW_BYTES */
+ 0xFF /* F - ATTRIB_RAW_PROCESS_BYTES */
+};
/*******************************************************************************
*
- * FUNCTION: acpi_ex_get_serial_access_length
+ * FUNCTION: acpi_ex_get_protocol_buffer_length
*
- * PARAMETERS: accessor_type - The type of the protocol indicated by region
+ * PARAMETERS: protocol_id - The type of the protocol indicated by region
* field access attributes
- * access_length - The access length of the region field
+ * return_length - Where the protocol byte transfer length is
+ * returned
*
- * RETURN: Decoded access length
+ * RETURN: Status and decoded byte transfer length
*
* DESCRIPTION: This routine returns the length of the generic_serial_bus
* protocol bytes
*
******************************************************************************/
-static u32
-acpi_ex_get_serial_access_length(u32 accessor_type, u32 access_length)
+acpi_status
+acpi_ex_get_protocol_buffer_length(u32 protocol_id, u32 *return_length)
{
- u32 length;
-
- switch (accessor_type) {
- case AML_FIELD_ATTRIB_QUICK:
-
- length = 0;
- break;
-
- case AML_FIELD_ATTRIB_SEND_RCV:
- case AML_FIELD_ATTRIB_BYTE:
-
- length = 1;
- break;
-
- case AML_FIELD_ATTRIB_WORD:
- case AML_FIELD_ATTRIB_WORD_CALL:
-
- length = 2;
- break;
-
- case AML_FIELD_ATTRIB_MULTIBYTE:
- case AML_FIELD_ATTRIB_RAW_BYTES:
- length = access_length;
- break;
-
- case AML_FIELD_ATTRIB_RAW_PROCESS:
- /*
- * Worst case bidirectional buffer size. This ignores the
- * access_length argument to access_as because it is not needed.
- * August 2018.
- */
- length = ACPI_MAX_GSBUS_BUFFER_SIZE;
- break;
-
- case AML_FIELD_ATTRIB_BLOCK:
- case AML_FIELD_ATTRIB_BLOCK_CALL:
- default:
+ if ((protocol_id > ACPI_MAX_PROTOCOL_ID) ||
+ (acpi_protocol_lengths[protocol_id] == ACPI_INVALID_PROTOCOL_ID)) {
+ ACPI_ERROR((AE_INFO,
+ "Invalid Field/AccessAs protocol ID: 0x%4.4X",
+ protocol_id));
- length = ACPI_GSBUS_BUFFER_SIZE - 2;
- break;
+ return (AE_AML_PROTOCOL);
}
- return (length);
+ *return_length = acpi_protocol_lengths[protocol_id];
+ return (AE_OK);
}
/*******************************************************************************
@@ -106,10 +115,8 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
{
acpi_status status;
union acpi_operand_object *buffer_desc;
- acpi_size length;
void *buffer;
- u32 function;
- u16 accessor_type;
+ u32 buffer_length;
ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
@@ -140,67 +147,11 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
ACPI_ADR_SPACE_GSBUS
|| obj_desc->field.region_obj->region.space_id ==
ACPI_ADR_SPACE_IPMI)) {
- /*
- * This is an SMBus, GSBus or IPMI read. We must create a buffer to
- * hold the data and then directly access the region handler.
- *
- * Note: SMBus and GSBus protocol value is passed in upper 16-bits
- * of Function
- */
- if (obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_SMBUS) {
- length = ACPI_SMBUS_BUFFER_SIZE;
- function =
- ACPI_READ | (obj_desc->field.attribute << 16);
- } else if (obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_GSBUS) {
- accessor_type = obj_desc->field.attribute;
- if (accessor_type == AML_FIELD_ATTRIB_RAW_PROCESS) {
- ACPI_ERROR((AE_INFO,
- "Invalid direct read using bidirectional write-then-read protocol"));
-
- return_ACPI_STATUS(AE_AML_PROTOCOL);
- }
- length =
- acpi_ex_get_serial_access_length(accessor_type,
- obj_desc->field.
- access_length);
-
- /*
- * Add additional 2 bytes for the generic_serial_bus data buffer:
- *
- * Status; (Byte 0 of the data buffer)
- * Length; (Byte 1 of the data buffer)
- * Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
- */
- length += 2;
- function = ACPI_READ | (accessor_type << 16);
- } else { /* IPMI */
-
- length = ACPI_IPMI_BUFFER_SIZE;
- function = ACPI_READ;
- }
+ /* SMBus, GSBus, IPMI serial */
- buffer_desc = acpi_ut_create_buffer_object(length);
- if (!buffer_desc) {
- return_ACPI_STATUS(AE_NO_MEMORY);
- }
-
- /* Lock entire transaction if requested */
-
- acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
-
- /* Call the region handler for the read */
-
- status = acpi_ex_access_region(obj_desc, 0,
- ACPI_CAST_PTR(u64,
- buffer_desc->
- buffer.pointer),
- function);
-
- acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
- goto exit;
+ status = acpi_ex_read_serial_bus(obj_desc, ret_buffer_desc);
+ return_ACPI_STATUS(status);
}
/*
@@ -213,14 +164,14 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
*
* Note: Field.length is in bits.
*/
- length =
+ buffer_length =
(acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
- if (length > acpi_gbl_integer_byte_width) {
+ if (buffer_length > acpi_gbl_integer_byte_width) {
/* Field is too large for an Integer, create a Buffer instead */
- buffer_desc = acpi_ut_create_buffer_object(length);
+ buffer_desc = acpi_ut_create_buffer_object(buffer_length);
if (!buffer_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
@@ -233,47 +184,24 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
return_ACPI_STATUS(AE_NO_MEMORY);
}
- length = acpi_gbl_integer_byte_width;
+ buffer_length = acpi_gbl_integer_byte_width;
buffer = &buffer_desc->integer.value;
}
if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
(obj_desc->field.region_obj->region.space_id ==
ACPI_ADR_SPACE_GPIO)) {
- /*
- * For GPIO (general_purpose_io), the Address will be the bit offset
- * from the previous Connection() operator, making it effectively a
- * pin number index. The bit_length is the length of the field, which
- * is thus the number of pins.
- */
- ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
- "GPIO FieldRead [FROM]: Pin %u Bits %u\n",
- obj_desc->field.pin_number_index,
- obj_desc->field.bit_length));
-
- /* Lock entire transaction if requested */
- acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+ /* General Purpose I/O */
- /* Perform the write */
-
- status =
- acpi_ex_access_region(obj_desc, 0, (u64 *)buffer,
- ACPI_READ);
-
- acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
- if (ACPI_FAILURE(status)) {
- acpi_ut_remove_reference(buffer_desc);
- } else {
- *ret_buffer_desc = buffer_desc;
- }
- return_ACPI_STATUS(status);
+ status = acpi_ex_read_gpio(obj_desc, buffer);
+ goto exit;
}
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"FieldRead [TO]: Obj %p, Type %X, Buf %p, ByteLen %X\n",
obj_desc, obj_desc->common.type, buffer,
- (u32) length));
+ buffer_length));
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
obj_desc->common_field.bit_length,
@@ -286,7 +214,7 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
/* Read from the field */
- status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
+ status = acpi_ex_extract_from_field(obj_desc, buffer, buffer_length);
acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
exit:
@@ -319,12 +247,8 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
union acpi_operand_object **result_desc)
{
acpi_status status;
- u32 length;
- u32 data_length;
+ u32 buffer_length;
void *buffer;
- union acpi_operand_object *buffer_desc;
- u32 function;
- u16 accessor_type;
ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
@@ -347,140 +271,25 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
}
} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
(obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_SMBUS
- || obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_GSBUS
- || obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_IPMI)) {
- /*
- * This is an SMBus, GSBus or IPMI write. We will bypass the entire
- * field mechanism and handoff the buffer directly to the handler.
- * For these address spaces, the buffer is bi-directional; on a
- * write, return data is returned in the same buffer.
- *
- * Source must be a buffer of sufficient size:
- * ACPI_SMBUS_BUFFER_SIZE, ACPI_GSBUS_BUFFER_SIZE, or
- * ACPI_IPMI_BUFFER_SIZE.
- *
- * Note: SMBus and GSBus protocol type is passed in upper 16-bits
- * of Function
- */
- if (source_desc->common.type != ACPI_TYPE_BUFFER) {
- ACPI_ERROR((AE_INFO,
- "SMBus/IPMI/GenericSerialBus write requires "
- "Buffer, found type %s",
- acpi_ut_get_object_type_name(source_desc)));
-
- return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
- }
-
- if (obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_SMBUS) {
- length = ACPI_SMBUS_BUFFER_SIZE;
- data_length = length;
- function =
- ACPI_WRITE | (obj_desc->field.attribute << 16);
- } else if (obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_GSBUS) {
- accessor_type = obj_desc->field.attribute;
- length =
- acpi_ex_get_serial_access_length(accessor_type,
- obj_desc->field.
- access_length);
-
- /*
- * Buffer format for Generic Serial Bus protocols:
- * Status; (Byte 0 of the data buffer)
- * Length; (Byte 1 of the data buffer)
- * Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
- */
- data_length = source_desc->buffer.pointer[1]; /* Data length is 2nd byte */
- if (!data_length) {
- ACPI_ERROR((AE_INFO,
- "Invalid zero data length in transfer buffer"));
-
- return_ACPI_STATUS(AE_AML_BUFFER_LENGTH);
- }
-
- function = ACPI_WRITE | (accessor_type << 16);
- } else { /* IPMI */
-
- length = ACPI_IPMI_BUFFER_SIZE;
- data_length = length;
- function = ACPI_WRITE;
- }
-
- if (source_desc->buffer.length < data_length) {
- ACPI_ERROR((AE_INFO,
- "SMBus/IPMI/GenericSerialBus write requires "
- "Buffer data length %u, found buffer length %u",
- data_length, source_desc->buffer.length));
-
- return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
- }
-
- /* Create the transfer/bidirectional buffer */
-
- buffer_desc = acpi_ut_create_buffer_object(length);
- if (!buffer_desc) {
- return_ACPI_STATUS(AE_NO_MEMORY);
- }
-
- /* Copy the input buffer data to the transfer buffer */
-
- buffer = buffer_desc->buffer.pointer;
- memcpy(buffer, source_desc->buffer.pointer, data_length);
-
- /* Lock entire transaction if requested */
-
- acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+ ACPI_ADR_SPACE_GPIO)) {
- /*
- * Perform the write (returns status and perhaps data in the
- * same buffer)
- */
- status =
- acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, function);
- acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+ /* General Purpose I/O */
- *result_desc = buffer_desc;
+ status = acpi_ex_write_gpio(source_desc, obj_desc, result_desc);
return_ACPI_STATUS(status);
} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
(obj_desc->field.region_obj->region.space_id ==
- ACPI_ADR_SPACE_GPIO)) {
- /*
- * For GPIO (general_purpose_io), we will bypass the entire field
- * mechanism and handoff the bit address and bit width directly to
- * the handler. The Address will be the bit offset
- * from the previous Connection() operator, making it effectively a
- * pin number index. The bit_length is the length of the field, which
- * is thus the number of pins.
- */
- if (source_desc->common.type != ACPI_TYPE_INTEGER) {
- return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
- }
-
- ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
- "GPIO FieldWrite [FROM]: (%s:%X), Val %.8X [TO]: Pin %u Bits %u\n",
- acpi_ut_get_type_name(source_desc->common.
- type),
- source_desc->common.type,
- (u32)source_desc->integer.value,
- obj_desc->field.pin_number_index,
- obj_desc->field.bit_length));
-
- buffer = &source_desc->integer.value;
-
- /* Lock entire transaction if requested */
-
- acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+ ACPI_ADR_SPACE_SMBUS
+ || obj_desc->field.region_obj->region.space_id ==
+ ACPI_ADR_SPACE_GSBUS
+ || obj_desc->field.region_obj->region.space_id ==
+ ACPI_ADR_SPACE_IPMI)) {
- /* Perform the write */
+ /* SMBus, GSBus, IPMI serial */
status =
- acpi_ex_access_region(obj_desc, 0, (u64 *)buffer,
- ACPI_WRITE);
- acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+ acpi_ex_write_serial_bus(source_desc, obj_desc,
+ result_desc);
return_ACPI_STATUS(status);
}
@@ -490,23 +299,22 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
case ACPI_TYPE_INTEGER:
buffer = &source_desc->integer.value;
- length = sizeof(source_desc->integer.value);
+ buffer_length = sizeof(source_desc->integer.value);
break;
case ACPI_TYPE_BUFFER:
buffer = source_desc->buffer.pointer;
- length = source_desc->buffer.length;
+ buffer_length = source_desc->buffer.length;
break;
case ACPI_TYPE_STRING:
buffer = source_desc->string.pointer;
- length = source_desc->string.length;
+ buffer_length = source_desc->string.length;
break;
default:
-
return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
}
@@ -514,7 +322,7 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
"FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
source_desc,
acpi_ut_get_type_name(source_desc->common.type),
- source_desc->common.type, buffer, length));
+ source_desc->common.type, buffer, buffer_length));
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"FieldWrite [TO]: Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
@@ -531,8 +339,352 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
/* Write to the field */
- status = acpi_ex_insert_into_field(obj_desc, buffer, length);
+ status = acpi_ex_insert_into_field(obj_desc, buffer, buffer_length);
+ acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_read_gpio
+ *
+ * PARAMETERS: obj_desc - The named field to read
+ * buffer - Where the return data is returnd
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Read from a named field that references a Generic Serial Bus
+ * field
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ex_read_gpio(union acpi_operand_object *obj_desc, void *buffer)
+{
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE_PTR(ex_read_gpio, obj_desc);
+
+ /*
+ * For GPIO (general_purpose_io), the Address will be the bit offset
+ * from the previous Connection() operator, making it effectively a
+ * pin number index. The bit_length is the length of the field, which
+ * is thus the number of pins.
+ */
+ ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
+ "GPIO FieldRead [FROM]: Pin %u Bits %u\n",
+ obj_desc->field.pin_number_index,
+ obj_desc->field.bit_length));
+
+ /* Lock entire transaction if requested */
+
+ acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+
+ /* Perform the read */
+
+ status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_READ);
+
+ acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_write_gpio
+ *
+ * PARAMETERS: source_desc - Contains data to write. Expect to be
+ * an Integer object.
+ * obj_desc - The named field
+ * result_desc - Where the return value is returned, if any
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Write to a named field that references a General Purpose I/O
+ * field.
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ex_write_gpio(union acpi_operand_object *source_desc,
+ union acpi_operand_object *obj_desc,
+ union acpi_operand_object **return_buffer)
+{
+ acpi_status status;
+ void *buffer;
+
+ ACPI_FUNCTION_TRACE_PTR(ex_write_gpio, obj_desc);
+
+ /*
+ * For GPIO (general_purpose_io), we will bypass the entire field
+ * mechanism and handoff the bit address and bit width directly to
+ * the handler. The Address will be the bit offset
+ * from the previous Connection() operator, making it effectively a
+ * pin number index. The bit_length is the length of the field, which
+ * is thus the number of pins.
+ */
+ if (source_desc->common.type != ACPI_TYPE_INTEGER) {
+ return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
+ "GPIO FieldWrite [FROM]: (%s:%X), Value %.8X [TO]: Pin %u Bits %u\n",
+ acpi_ut_get_type_name(source_desc->common.type),
+ source_desc->common.type,
+ (u32)source_desc->integer.value,
+ obj_desc->field.pin_number_index,
+ obj_desc->field.bit_length));
+
+ buffer = &source_desc->integer.value;
+
+ /* Lock entire transaction if requested */
+
+ acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+
+ /* Perform the write */
+
+ status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_WRITE);
+ acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_read_serial_bus
+ *
+ * PARAMETERS: obj_desc - The named field to read
+ * return_buffer - Where the return value is returned, if any
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Read from a named field that references a serial bus
+ * (SMBus, IPMI, or GSBus).
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ex_read_serial_bus(union acpi_operand_object *obj_desc,
+ union acpi_operand_object **return_buffer)
+{
+ acpi_status status;
+ u32 buffer_length;
+ union acpi_operand_object *buffer_desc;
+ u32 function;
+ u16 accessor_type;
+
+ ACPI_FUNCTION_TRACE_PTR(ex_read_serial_bus, obj_desc);
+
+ /*
+ * This is an SMBus, GSBus or IPMI read. We must create a buffer to
+ * hold the data and then directly access the region handler.
+ *
+ * Note: SMBus and GSBus protocol value is passed in upper 16-bits
+ * of Function
+ *
+ * Common buffer format:
+ * Status; (Byte 0 of the data buffer)
+ * Length; (Byte 1 of the data buffer)
+ * Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
+ */
+ switch (obj_desc->field.region_obj->region.space_id) {
+ case ACPI_ADR_SPACE_SMBUS:
+
+ buffer_length = ACPI_SMBUS_BUFFER_SIZE;
+ function = ACPI_READ | (obj_desc->field.attribute << 16);
+ break;
+
+ case ACPI_ADR_SPACE_IPMI:
+
+ buffer_length = ACPI_IPMI_BUFFER_SIZE;
+ function = ACPI_READ;
+ break;
+
+ case ACPI_ADR_SPACE_GSBUS:
+
+ accessor_type = obj_desc->field.attribute;
+ if (accessor_type == AML_FIELD_ATTRIB_RAW_PROCESS_BYTES) {
+ ACPI_ERROR((AE_INFO,
+ "Invalid direct read using bidirectional write-then-read protocol"));
+
+ return_ACPI_STATUS(AE_AML_PROTOCOL);
+ }
+
+ status =
+ acpi_ex_get_protocol_buffer_length(accessor_type,
+ &buffer_length);
+ if (ACPI_FAILURE(status)) {
+ ACPI_ERROR((AE_INFO,
+ "Invalid protocol ID for GSBus: 0x%4.4X",
+ accessor_type));
+
+ return_ACPI_STATUS(status);
+ }
+
+ /* Add header length to get the full size of the buffer */
+
+ buffer_length += ACPI_SERIAL_HEADER_SIZE;
+ function = ACPI_READ | (accessor_type << 16);
+ break;
+
+ default:
+ return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
+ }
+
+ /* Create the local transfer buffer that is returned to the caller */
+
+ buffer_desc = acpi_ut_create_buffer_object(buffer_length);
+ if (!buffer_desc) {
+ return_ACPI_STATUS(AE_NO_MEMORY);
+ }
+
+ /* Lock entire transaction if requested */
+
+ acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+
+ /* Call the region handler for the write-then-read */
+
+ status = acpi_ex_access_region(obj_desc, 0,
+ ACPI_CAST_PTR(u64,
+ buffer_desc->buffer.
+ pointer), function);
+ acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+
+ *return_buffer = buffer_desc;
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_write_serial_bus
+ *
+ * PARAMETERS: source_desc - Contains data to write
+ * obj_desc - The named field
+ * return_buffer - Where the return value is returned, if any
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Write to a named field that references a serial bus
+ * (SMBus, IPMI, GSBus).
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ex_write_serial_bus(union acpi_operand_object *source_desc,
+ union acpi_operand_object *obj_desc,
+ union acpi_operand_object **return_buffer)
+{
+ acpi_status status;
+ u32 buffer_length;
+ u32 data_length;
+ void *buffer;
+ union acpi_operand_object *buffer_desc;
+ u32 function;
+ u16 accessor_type;
+
+ ACPI_FUNCTION_TRACE_PTR(ex_write_serial_bus, obj_desc);
+
+ /*
+ * This is an SMBus, GSBus or IPMI write. We will bypass the entire
+ * field mechanism and handoff the buffer directly to the handler.
+ * For these address spaces, the buffer is bidirectional; on a
+ * write, return data is returned in the same buffer.
+ *
+ * Source must be a buffer of sufficient size, these are fixed size:
+ * ACPI_SMBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
+ *
+ * Note: SMBus and GSBus protocol type is passed in upper 16-bits
+ * of Function
+ *
+ * Common buffer format:
+ * Status; (Byte 0 of the data buffer)
+ * Length; (Byte 1 of the data buffer)
+ * Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
+ */
+ if (source_desc->common.type != ACPI_TYPE_BUFFER) {
+ ACPI_ERROR((AE_INFO,
+ "SMBus/IPMI/GenericSerialBus write requires "
+ "Buffer, found type %s",
+ acpi_ut_get_object_type_name(source_desc)));
+
+ return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
+ }
+
+ switch (obj_desc->field.region_obj->region.space_id) {
+ case ACPI_ADR_SPACE_SMBUS:
+
+ buffer_length = ACPI_SMBUS_BUFFER_SIZE;
+ data_length = ACPI_SMBUS_DATA_SIZE;
+ function = ACPI_WRITE | (obj_desc->field.attribute << 16);
+ break;
+
+ case ACPI_ADR_SPACE_IPMI:
+
+ buffer_length = ACPI_IPMI_BUFFER_SIZE;
+ data_length = ACPI_IPMI_DATA_SIZE;
+ function = ACPI_WRITE;
+ break;
+
+ case ACPI_ADR_SPACE_GSBUS:
+
+ accessor_type = obj_desc->field.attribute;
+ status =
+ acpi_ex_get_protocol_buffer_length(accessor_type,
+ &buffer_length);
+ if (ACPI_FAILURE(status)) {
+ ACPI_ERROR((AE_INFO,
+ "Invalid protocol ID for GSBus: 0x%4.4X",
+ accessor_type));
+
+ return_ACPI_STATUS(status);
+ }
+
+ /* Add header length to get the full size of the buffer */
+
+ buffer_length += ACPI_SERIAL_HEADER_SIZE;
+ data_length = source_desc->buffer.pointer[1];
+ function = ACPI_WRITE | (accessor_type << 16);
+ break;
+
+ default:
+ return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
+ }
+
+#if 0
+ OBSOLETE ?
+ /* Check for possible buffer overflow */
+ if (data_length > source_desc->buffer.length) {
+ ACPI_ERROR((AE_INFO,
+ "Length in buffer header (%u)(%u) is greater than "
+ "the physical buffer length (%u) and will overflow",
+ data_length, buffer_length,
+ source_desc->buffer.length));
+
+ return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
+ }
+#endif
+
+ /* Create the transfer/bidirectional/return buffer */
+
+ buffer_desc = acpi_ut_create_buffer_object(buffer_length);
+ if (!buffer_desc) {
+ return_ACPI_STATUS(AE_NO_MEMORY);
+ }
+
+ /* Copy the input buffer data to the transfer buffer */
+
+ buffer = buffer_desc->buffer.pointer;
+ memcpy(buffer, source_desc->buffer.pointer, data_length);
+
+ /* Lock entire transaction if requested */
+
+ acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+
+ /*
+ * Perform the write (returns status and perhaps data in the
+ * same buffer)
+ */
+ status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, function);
acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
+ *return_buffer = buffer_desc;
return_ACPI_STATUS(status);
}