Secure information processing
Apparatus, systems, and methods may operate to receive from a requesting device, at a memory device, a request to access a memory domain associated with the memory device, and to deny, by the memory device, the request if the memory domain comprises any part of a secure domain, and the requesting device has not asserted a secure transfer indication. Additional operations may include granting the request if the memory domain comprises some part of the secure domain and the requesting device has asserted the secure transfer signal, or if the memory domain comprises only a non-secure domain. Additional apparatus, systems, and methods are disclosed.
1. An apparatus comprising:
a substrate;
an array of memory cells supported by the substrate;
a register supported by the substrate, wherein the register includes information that associates a secure domain with a subset of the array, wherein access to the secure domain is granted responsive to receiving a request to access the secure domain in conjunction with a secure transfer indication; and
a secure domain fuse configured to restrict access to the secure domain and to secure system registers, the secure domain fuse having states that are configured to perform at least one operation selected from the group consisting of:
enable and disable secure access to the array,
enable and disable security permission checking for accesses to the array, and determine whether a system coupled to the apparatus boots in a secure world or a non-secure world.
2. The apparatus of claim 1 , comprising:
a secure debug fuse having states that are configured to enable and disable at least one of tracing, single-step, or breakpoint activity associated with information stored in the secure domain.
3. The apparatus of claim 1 , comprising:
at least one register to define at least one of a size or a location of the secure domain within the array.
4. The apparatus of claim 1 , comprising:
secure system registers that are configured to indicate at least one of an execution status of information associated with the secure domain and a configuration of the secure domain, wherein the secure system registers are configured to be written based on a secure state being indicated by a processor coupled to the apparatus, and
wherein the secure system registers are configured to be read independent of whether the secure state is indicated.
5. The apparatus of claim 4 , wherein the secure system registers are loaded at boot time associated with the apparatus for at least one of indicating a starting address of the secure domain and size of the secure domain.
6. A method comprising:
receiving, at a memory device and from a bus master, a request to access an array of memory cells associated with the memory device, wherein the array includes a secure domain associated with the memory device based on information included in a register;
determining, by the memory device, whether the request is received in conjunction with a secure transfer indication by the bus master;
in response to determining that the request is received in conjunction with the secure transfer indication, checking a state associated with a secure domain fuse that is configured to restrict access to the secure domain, the secure domain fuse having states that are configured to perform at least one operation selected from the group consisting of:
enable and disable secure access to the array,
enable and disable security permission checking for accesses to the array, and
determine whether bus master performing the request boots in a secure world or a non-secure world; and
granting access to the array including the secure domain based on the state associated with the secure domain fuse.
7. The method of claim 6 , wherein the memory device includes a secure debug fuse, the method comprising:
configuring, by the memory device, an activity associated with information stored in the array based on a state of the secure debug fuse, the activity comprising enabling and disabling at least one of tracing, single-step, or breakpoint activity associated with the information stored in the array.
8. The method of claim 6 , wherein the register includes information on at least one of a size or a location of the secure domain within the array.
9. The method of claim 6 , wherein the memory device includes secure system registers that are configured to indicate at least one of an execution status of information associated with the secure domain and a configuration of the secure domain, the method comprising:
writing to the secure system registers based on a secure state being indicated by a processor coupled to the memory device; and
reading from the secure system registers independent of whether the secure state is indicated.
10. The method of claim 9 , wherein the secure system registers are loaded at boot time associated with the memory device for at least one of indicating a starting address of the secure domain and size of the secure domain.
11. A system comprising:
a processor; and
instructions embedded in a non-transitory machine-readable medium for execution by the processor and configured to cause the processor to perform operations comprising:
receiving, at a memory device and from a bus master, a request to access an array of memory cells associated with the memory device, wherein the array includes a secure domain associated with the memory device based on information included in a register;
determining, by the memory device, whether the request is received in conjunction with a secure transfer indication by the bus master;
in response to determining that the request is received in conjunction with the secure transfer indication, checking a state associated with a secure domain fuse that is configured to restrict access to the secure domain, the secure domain fuse having states that are configured to perform at least one operation selected from the group consisting of:
enable and disable secure access to the array,
enable and disable security permission checking for accesses to the array, and
determine whether bus master performing the request boots in a secure world or a non-secure world; and
granting access to the array including the secure domain based on the state associated with the secure domain fuse.
12. The system of claim 11 , wherein the memory device includes a secure debug fuse, the system including instructions that are configured to cause the processor to perform operations comprising:
configuring, by the memory device, an activity associated with information stored in the array based on a state of the secure debug fuse, the activity comprising enabling and disabling at least one of tracing, single-step, or breakpoint activity associated with the information stored in the array.
13. The system of claim 11 , wherein the register includes information on at least one of a size or a location of the secure domain within the array.
14. The system of claim 11 , wherein the memory device includes secure system registers that are configured to indicate at least one of an execution status of information associated with the secure domain and a configuration of the secure domain, the system including instructions that are configured to cause the processor to perform operations comprising:
writing to the secure system registers based on a secure state being indicated by the processor; and
reading from the secure system registers independent of whether the secure state is indicated.
15. The system of claim 14 , wherein the secure system registers are loaded at boot time associated with the memory device for at least one of indicating a starting address of the secure domain and size of the secure domain.