refactor(cpufeat): enable SYS_REG_TRACE for FEAT_STATE_CHECKED
At the moment we only support access to the trace unit by system
registers (SYS_REG_TRACE) to be either unconditionally compiled in, or
to be not supported at all.
Add support for runtime detection (ENABLE_SYS_REG_TRACE_FOR_NS=2), by
adding is_feat_sys_reg_trace_supported(). That function considers both
build time settings and runtime information (if needed), and is used
before we access SYS_REG_TRACE related registers.
The FVP platform decided to compile in support unconditionally (=1),
even though this is an optional feature, so it is not available with the
FVP model's default command line.
Change that to the now supported dynamic option (=2), so the right
decision can be made by the code at runtime.
Change-Id: I450a574a4f6bd9fc269887037049c94c906f54b2
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/lib/extensions/sys_reg_trace/aarch32/sys_reg_trace.c b/lib/extensions/sys_reg_trace/aarch32/sys_reg_trace.c
index 89b8029..b3f44b7 100644
--- a/lib/extensions/sys_reg_trace/aarch32/sys_reg_trace.c
+++ b/lib/extensions/sys_reg_trace/aarch32/sys_reg_trace.c
@@ -10,27 +10,16 @@
#include <arch_helpers.h>
#include <lib/extensions/sys_reg_trace.h>
-static bool sys_reg_trace_supported(void)
-{
- uint32_t features;
-
- features = read_id_dfr0() >> ID_DFR0_COPTRC_SHIFT;
- return ((features & ID_DFR0_COPTRC_MASK) ==
- ID_DFR0_COPTRC_SUPPORTED);
-}
-
void sys_reg_trace_enable(void)
{
uint32_t val;
- if (sys_reg_trace_supported()) {
- /*
- * NSACR.NSTRCDIS = b0
- * enable NS system register access to implemented trace
- * registers.
- */
- val = read_nsacr();
- val &= ~NSTRCDIS_BIT;
- write_nsacr(val);
- }
+ /*
+ * NSACR.NSTRCDIS = b0
+ * enable NS system register access to implemented trace
+ * registers.
+ */
+ val = read_nsacr();
+ val &= ~NSTRCDIS_BIT;
+ write_nsacr(val);
}