Method and apparatus for using a memory region to pass parameters between a run time environment and SMM handler

• US 7,178,014 B2
• Filed: 09/04/2002
• Issued: 02/13/2007
• Est. Priority Date: 09/04/2002
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Nalawadi, Rajeev K., Munoz, Victor M.
• Primary Examiner(s): ELAMIN, ABDELMONIEM I
• Application Number:
  US10/236,570
• Publication Number:
  US 20040044888A1
• Time in Patent Office: 1,623 Days
• Field of Search: 713/1, 713/2, 713/100, 713/300, 711/153, 711/170, 711/173
• US Class Current: 713/1
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers

Abstract

An ACPI (Non-Volatile Sleeping) NVS memory region is allocated and defined so that a system BIOS can allocate a placeholder for the different parameters that are passed from the ACPI ASL code to the system management mode (SMM) handler for execution of real mode calls. The different parameters will be updated by runtime ACPI ASL code depending on what needs to be passed to the SMM handler. The SMM handler invokes appropriate calls based on retrieving of different parameters in the ACPI NVS memory region that have been passed from the ACPI ASL code.

Claims

1. A computer system comprising:

a memory coupled to a bus, the memory mapped according to a predetermined specification;

a device controller coupled to the bus; and

a basic input-output system (BIOS) coupled to the bus, the BIOS having a device support component to provide support for a device using a portion of a defined region of the memory to maintain and pass parameters when a SMM handler is invoked from an ACPI ASL code.

2. The system of claim 1, wherein:

the predetermined specification is the Advanced Configuration and Power Interlace (ACPI) specification; and

the defined region is the non-volatile sleeping (NVS) region defined by the ACPI specification.

3. The system of claim 2, wherein the parameters are updated by ACPI ASL code in response to the calls invoked by the SMM handler.

4. The system of claim 2, wherein the defined region is defined by an operation region offset, length and bit-length values.

5. A system comprising:

a memory coupled to a bus;

a device controller coupled to the bus;

a basic input-output system (BIOS) coupled to the bus, the BIOS having instructions which when executed cause the processor to perform operations including;

mapping the memory pursuant to a predetermined specification to include a defined region of the memory;

allocating a portion of the defined region of the memory to be used to maintain and pass parameters when a SMM handler is invoked from an ACPI ASL code.

6. The system of claim 5, wherein:

the predetermined specification is the Advanced Configuration and Power Interface (ACPI) specification; and

the defined region is the non-volatile sleeping (NVS) region defined by the ACPI specification and used for passing parameters to other components of the software.

7. The system of claim 6, wherein the parameters are updated by ACPI ASL code in response to the calls invoked by the SMM handler.

8. The system of claim 6, wherein allocating a portion of the defined region of the memory to be used to maintain and pass parameters when a SMM handler is invoked from the ACPI ASL code includes:

defining the region by operation region offset, length and bit-length values.

9. A method for using an ACPI NVS memory region to pass parameters between a runtime environment and SMM handler, comprising:

configuring the ACPI NVS memory region to include a parameter region to maintain and pass parameters when a SMM handler is invoked from an ACPI ASL control mode;

updating parameters in the ACPI NVS memory region;

invoking a SMM handler mode;

performing real-mode calls while operating in the SMM handler mode; and

returning control to the ACPI ASL control mode after the real mode calls are performed.

10. The method of claim 9, wherein invoking a SMM handler mode further comprises:

writing to a predefined I/O trap address.

11. The method of claim 10, wherein invoking a SMM handler mode further comprises:

determine what parameters have been passed depending on which different tasks can be invoked from the SMM handler; and

determine the function number associated with the I/O trap address.

12. A machine readable storage medium having stored therein a plurality of machine readable instructions executable by a processor to use an ACPI NVS memory region to pass parameters between a runtime environment and SMM handler, comprising:

instructions to configure the ACPI NVS memory region to include a parameter region to maintain and pass parameters when a SMM handler is invoked from an ACPI ASL control mode;

instructions to update parameters in the ACPI NVS memory region;

instructions to invoke a SMM handler mode;

instructions to perform real-mode calls while operating in the SMM handler mode; and

instructions to return control to the ACPI ASL control mode after the real mode calls are performed.

13. The machine readable medium of claim 12, wherein instructions to invoke a SMM handler mode further comprises:

instructions to write to a predefined I/O trap address.

14. The machine readable medium of claim 12, wherein instructions to invoke a SMM handler mode further comprises:

instructions to determine what parameters have been passed depending on which different tasks can be invoked from the SMM handler; and

instructions to determine the function number associated with the I/O trap address.

15. The machine readable medium of claim 12, further comprising:

instructions to limit access to a portion of the ACPI NVS memory region.