OPAL_LPC_READ

#define OPAL_LPC_READ                                67

/*
 * Address cycle types for LPC accesses. These also correspond
 * to the content of the first cell of the "reg" property for
 * device nodes on the LPC bus
 */
 enum OpalLPCAddressType {
   OPAL_LPC_MEM      = 0,
   OPAL_LPC_IO       = 1,
   OPAL_LPC_FW       = 2,
};

int64_t opal_lpc_read(uint32_t chip_id, enum OpalLPCAddressType addr_type,
                          uint32_t addr, uint32_t *data, uint32_t sz);

This function related to Low Pin Count (LPC) bus. This function reads the data from IDSEL register for chip_id, which has LPC information. From addr for addr_type with read size sz bytes in to a variable named data.

Parameters

chip_id
The chip_id parameter contains value of the chip number identified at boot time.
addr_type

The addr_type is one of the LPC supported address types. Supported address types are:

  • LPC memory,
  • LPC IO and
  • LPC firmware.
addr
The addr from which the data has to be read.
data
The data will be used to store the read data.
sz
How many sz bytes to be read in to data.

Return Codes

OPAL_PARAMETER
Indicates either chip_id not found or chip_id doesn’t contain LPC information.
OPAL_SUCCESS
Indicates Success!

OPAL_LPC_WRITE

#define OPAL_LPC_WRITE                               68

/*
 * Address cycle types for LPC accesses. These also correspond
 * to the content of the first cell of the "reg" property for
 * device nodes on the LPC bus
 */
 enum OpalLPCAddressType {
   OPAL_LPC_MEM      = 0,
   OPAL_LPC_IO       = 1,
   OPAL_LPC_FW       = 2,
};

int64_t opal_lpc_write(uint32_t chip_id, enum OpalLPCAddressType addr_type,
                       uint32_t addr, uint32_t data, uint32_t sz);

This function related to Low Pin Count (LPC) bus. This function writes the data in to ECCB register for chip_id, which has LPC information. From addr for addr_type with write size sz bytes.

Parameters

chip_id
The chip_id parameter contains value of the chip number identified at boot time.
addr_type

The addr_type is one of the address types LPC supported. Supported address types are:

  • LPC memory,
  • LPC IO and
  • LPC firmware.
addr
The addr to where the data need to be written.
data
The data for writing.
sz
How many sz bytes to write.

Return Codes

OPAL_PARAMETER
Indicates either chip_id not found or chip_id doesn’t contain LPC information.
OPAL_SUCCESS
Indicates Success!