Djam/arm-trusted-firmware
1
0
Fork 0
mirror of https://github.com/ARM-software/arm-trusted-firmware.git synced 2025-04-16 09:34:18 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

refactor(brbe): enable FEAT_BRBE for FEAT_STATE_CHECKED

Browse source 
At the moment we only support FEAT_BRBE to be either unconditionally
compiled in, or to be not supported at all.

Add support for runtime detection (ENABLE_BRBE_FOR_NS=2), by splitting
is_feat_brbe_present() into an ID register reading function and a second
function to report the support status. That function considers both
build time settings and runtime information (if needed), and is used
before we access BRBE related registers.

The FVP platform decided to compile in support unconditionally (=1),
even though FEAT_BRBE is an ARMv9 feature, so 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: I5f2e2c9648300f65f0fa9a5f8e2f34e73529d053
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
This commit is contained in:
Andre Przywara 2022-11-17 16:42:09 +00:00
parent f5360cfa81
commit ff49103660
6 changed files with 32 additions and 31 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
bl31/bl31.mk
View file

@ -116,7 +116,7 @@ ifneq (${ENABLE_TRBE_FOR_NS},0)
BL31_SOURCES += lib/extensions/trbe/trbe.c
endif
ifeq (${ENABLE_BRBE_FOR_NS},1)
ifneq (${ENABLE_BRBE_FOR_NS},0)
BL31_SOURCES += lib/extensions/brbe/brbe.c
endif

13
common/feat_detect.c
View file

@ -248,16 +248,6 @@ static void read_feat_rme(void)
#endif
}
/******************************************************
* Feature : FEAT_BRBE (Branch Record Buffer Extension)
*****************************************************/
static void read_feat_brbe(void)
{
#if (ENABLE_BRBE_FOR_NS == FEAT_STATE_ALWAYS)
feat_detect_panic(is_feat_brbe_present(), "BRBE");
#endif
}
/******************************************************************
* Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS)
*****************************************************************/
@ -334,7 +324,8 @@ void detect_arch_features(void)
check_feature(ENABLE_FEAT_HCX, read_feat_hcx_id_field(), "HCX", 1, 1);
/* v9.0 features */
read_feat_brbe();
check_feature(ENABLE_BRBE_FOR_NS, read_feat_brbe_id_field(),
"BRBE", 1, 2);
check_feature(ENABLE_TRBE_FOR_NS, read_feat_trbe_id_field(),
"TRBE", 1, 1);

18
include/arch/aarch64/arch_features.h
View file

@ -288,10 +288,22 @@ static inline unsigned int get_armv8_4_feat_nv_support(void)
* Function to identify the presence of FEAT_BRBE (Branch Record Buffer
* Extension)
******************************************************************************/
static inline bool is_feat_brbe_present(void)
static inline unsigned int read_feat_brbe_id_field(void)
{
return (((read_id_aa64dfr0_el1() >> ID_AA64DFR0_BRBE_SHIFT) &
ID_AA64DFR0_BRBE_MASK) == ID_AA64DFR0_BRBE_SUPPORTED);
return ISOLATE_FIELD(read_id_aa64dfr0_el1(), ID_AA64DFR0_BRBE);
}
static inline bool is_feat_brbe_supported(void)
{
if (ENABLE_BRBE_FOR_NS == FEAT_STATE_DISABLED) {
return false;
}
if (ENABLE_BRBE_FOR_NS == FEAT_STATE_ALWAYS) {
return true;
}
return read_feat_brbe_id_field() != 0U;
}
/*******************************************************************************

6
lib/el3_runtime/aarch64/context_mgmt.c
View file

@ -499,9 +499,9 @@ static void manage_extensions_nonsecure(bool el2_unused, cpu_context_t *ctx)
trbe_enable();
}
#if ENABLE_BRBE_FOR_NS
brbe_enable();
#endif /* ENABLE_BRBE_FOR_NS */
if (is_feat_brbe_supported()) {
brbe_enable();
}
#if ENABLE_SYS_REG_TRACE_FOR_NS
sys_reg_trace_enable(ctx);

22
lib/extensions/brbe/brbe.c
View file

@ -12,16 +12,14 @@ void brbe_enable(void)
{
uint64_t val;
if (is_feat_brbe_present()) {
/*
* MDCR_EL3.SBRBE = 0b01
*
* Allows BRBE usage in non-secure world and prohibited in
* secure world.
*/
val = read_mdcr_el3();
val &= ~(MDCR_SBRBE_MASK << MDCR_SBRBE_SHIFT);
val |= (0x1UL << MDCR_SBRBE_SHIFT);
write_mdcr_el3(val);
}
/*
* MDCR_EL3.SBRBE = 0b01
*
* Allows BRBE usage in non-secure world and prohibited in
* secure world.
*/
val = read_mdcr_el3();
val &= ~(MDCR_SBRBE_MASK << MDCR_SBRBE_SHIFT);
val |= (0x1UL << MDCR_SBRBE_SHIFT);
write_mdcr_el3(val);
}

2
plat/arm/board/fvp/platform.mk
View file

@ -453,7 +453,7 @@ ENABLE_TRBE_FOR_NS := 2
# do not enable when ENABLE_RME=1
ifeq (${ARCH}, aarch64)
ifeq (${ENABLE_RME},0)
ENABLE_BRBE_FOR_NS := 1
ENABLE_BRBE_FOR_NS := 2
endif
endif