Hi Pankaj,
You are correct, TLS 1.1 and 1.2 is supported since R12.52 SP1 CR07, and to upgrade from R12.52 SP1 CR01 to CR07, it is not like a whole release upgrade, but the components can be upgraded separately as they support other components on the same release in different CR (as covered in the Platform Support Matrix), except the AdminUI which is highly recommended to have the same CR as the Policy Server.
Tech Tip - CA Single Sign-On:Policy Server:Does Policy server supports TLSv1.1/TLSv1.2 protocol for LDAP connectivity with Policy Store/User Store
R12.52 Platform Support Matrix
So to upgrade Policy Server you should stop it, perform the upgrade, and also upgrade the Policy Store as between CRs sometimes there are some enhancements and fixes that includes some changes to existing objects, and therefore using upgrade tools as per documentation is recommended (XPSDDInstall, XPSimport for the default objects, etc), as this step is harmless and will only modify existing objects if they are updated on this CR, or if they are damaged/missing.
Upgrading - CA Single Sign-On - 12.52 SP1 - CA Technologies Documentation
Anyway, it is always recommended to have all components in the same version and CR, but you have more flexibility to apply the CR07 to other components as they are supported as mentioned above.
Hope it helps!