AArch32: Disable Secure Cycle Counter
This patch changes implementation for disabling Secure Cycle
Counter. For ARMv8.5 the counter gets disabled by setting
SDCR.SCCD bit on CPU cold/warm boot. For the earlier
architectures PMCR register is saved/restored on secure
world entry/exit from/to Non-secure state, and cycle counting
gets disabled by setting PMCR.DP bit.
In 'include\aarch32\arch.h' header file new
ARMv8.5-PMU related definitions were added.
Change-Id: Ia8845db2ebe8de940d66dff479225a5b879316f8
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
diff --git a/lib/el3_runtime/aarch32/context_mgmt.c b/lib/el3_runtime/aarch32/context_mgmt.c
index a4702fc..73d1e35 100644
--- a/lib/el3_runtime/aarch32/context_mgmt.c
+++ b/lib/el3_runtime/aarch32/context_mgmt.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -281,10 +281,28 @@
*
* HDCR.HPMN: Set to value of PMCR.N which is the
* architecturally-defined reset value.
+ *
+ * HDCR.HLP: Set to one so that event counter
+ * overflow, that is recorded in PMOVSCLR[0-30],
+ * occurs on the increment that changes
+ * PMEVCNTR<n>[63] from 1 to 0, when ARMv8.5-PMU is
+ * implemented. This bit is RES0 in versions of the
+ * architecture earlier than ARMv8.5, setting it to 1
+ * doesn't have any effect on them.
+ * This bit is Reserved, UNK/SBZP in ARMv7.
+ *
+ * HDCR.HPME: Set to zero to disable EL2 Event
+ * counters.
*/
- write_hdcr(HDCR_RESET_VAL |
- ((read_pmcr() & PMCR_N_BITS) >> PMCR_N_SHIFT));
-
+#if (ARM_ARCH_MAJOR > 7)
+ write_hdcr((HDCR_RESET_VAL | HDCR_HLP_BIT |
+ ((read_pmcr() & PMCR_N_BITS) >>
+ PMCR_N_SHIFT)) & ~HDCR_HPME_BIT);
+#else
+ write_hdcr((HDCR_RESET_VAL |
+ ((read_pmcr() & PMCR_N_BITS) >>
+ PMCR_N_SHIFT)) & ~HDCR_HPME_BIT);
+#endif
/*
* Set HSTR to its architectural reset value so that
* access to system registers in the cproc=1111