arm-trusted-firmware/lib/cpus
Varun Wadekar c5c1af0db6 cpus: denver: disable cycle counter when event counting is prohibited
The Denver CPUs implement support for PMUv3 for ARMv8.1 and expect the
PMCR_EL0 to be saved in non-secure context.

This patch disables cycle counter when event counting is prohibited
immediately on entering the secure world to avoid leaking useful
information about the PMU counters. The context saving code later
saves the value of PMCR_EL0 to the non-secure world context.

Verified with 'PMU Leakage' test suite.

 ******************************* Summary *******************************
 > Test suite 'PMU Leakage'
                                                                 Passed
 =================================
 Tests Skipped : 2
 Tests Passed  : 2
 Tests Failed  : 0
 Tests Crashed : 0
 Total tests   : 4
 =================================

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I3675e2b99b44ed23d86e29a5af1b496e80324875
2020-06-09 19:54:29 +00:00
..
aarch32 Cortex A9:errata 794073 workaround 2019-04-12 10:10:32 +00:00
aarch64 cpus: denver: disable cycle counter when event counting is prohibited 2020-06-09 19:54:29 +00:00
cpu-ops.mk Rename Cortex-Hercules to Cortex-A78 2020-06-01 17:33:22 -05:00
errata_report.c Coverity: remove unnecessary header file includes 2020-02-04 10:23:51 -06:00