US 11,984,183 B2
Systems and methods for fault-resilient system management random access memory
Balasingh P. Samuel, Round Rock, TX (US); Michael W. Arms, Copperas Cove, TX (US); and Vivek Viswanathan Iyer, Austin, TX (US)
Assigned to Dell Products L.P., Round Rock, TX (US)
Filed by Dell Products L.P., Round Rock, TX (US)
Filed on Feb. 1, 2022, as Appl. No. 17/590,214.
Prior Publication US 2023/0245709 A1, Aug. 3, 2023
Int. Cl. G11C 29/46 (2006.01); G06F 11/20 (2006.01)
CPC G11C 29/46 (2013.01) [G06F 11/2094 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An information handling system comprising:
a processor;
a memory communicatively coupled to the processor; and
a basic input/output system communicatively coupled to the processor and comprising a program of executable instructions configured to:
maintain a System Management Random Access Memory (SMRAM) test flag indicative of a requirement to test a designated region of memory configured as an SMRAM for use in a System Management Mode (SMM) mode of operation; and
during a Pre-Extensible Firmware Interface Initialization (PEI) phase of the basic input/output system, responsive to detecting that the SMRAM test flag is set:
test the designated region and responsive to detecting a memory fault:
map out the designated region and designate an additional region of the memory as a designated region for SMRAM; and
repeat testing of additional designated regions, mapping out of failed additional designated regions, and designating new additional regions of the memory until a designated region passes testing without memory fault; and
in response to detecting passage of testing without memory fault of a designated region comprising either of the first designated region or an additional region of the memory, configure the designated region for use as the SMRAM for the information handling system; and
responsive to a system management interrupt (SMI), configure the information handling system to enter the SMM, in which the SMRAM is configured as a separate address space dedicated for executing SMM code.