Merge pull request #997 from dp-arm/dp/spe
aarch64: Enable Statistical Profiling Extensions for lower ELs
diff --git a/Makefile b/Makefile
index aec10c9..31964de 100644
--- a/Makefile
+++ b/Makefile
@@ -454,6 +454,7 @@
$(eval $(call assert_boolean,USE_COHERENT_MEM))
$(eval $(call assert_boolean,USE_TBBR_DEFS))
$(eval $(call assert_boolean,WARMBOOT_ENABLE_DCACHE_EARLY))
+$(eval $(call assert_boolean,ENABLE_SPE_FOR_LOWER_ELS))
$(eval $(call assert_numeric,ARM_ARCH_MAJOR))
$(eval $(call assert_numeric,ARM_ARCH_MINOR))
@@ -493,6 +494,7 @@
$(eval $(call add_define,USE_COHERENT_MEM))
$(eval $(call add_define,USE_TBBR_DEFS))
$(eval $(call add_define,WARMBOOT_ENABLE_DCACHE_EARLY))
+$(eval $(call add_define,ENABLE_SPE_FOR_LOWER_ELS))
# Define the EL3_PAYLOAD_BASE flag only if it is provided.
ifdef EL3_PAYLOAD_BASE
diff --git a/docs/user-guide.md b/docs/user-guide.md
index 0065ac0..d5423ca 100644
--- a/docs/user-guide.md
+++ b/docs/user-guide.md
@@ -542,6 +542,11 @@
cluster platforms). If this option is enabled, then warm boot path
enables D-caches immediately after enabling MMU. This option defaults to 0.
+* `ENABLE_SPE_FOR_LOWER_ELS` : Boolean option to enable Statistical Profiling
+ extensions. This is an optional architectural feature available only for
+ AArch64 8.2 onwards. This option defaults to 1 but is automatically
+ disabled when the target architecture is AArch32 or AArch64 8.0/8.1.
+
#### ARM development platform specific build options
* `ARM_BL31_IN_DRAM`: Boolean option to select loading of BL31 in TZC secured
diff --git a/include/common/aarch64/el3_common_macros.S b/include/common/aarch64/el3_common_macros.S
index ed35df8..34fdaee 100644
--- a/include/common/aarch64/el3_common_macros.S
+++ b/include/common/aarch64/el3_common_macros.S
@@ -95,6 +95,10 @@
* MDCR_EL3.SPD32: Set to 0b10 to disable AArch32 Secure self-hosted
* privileged debug from S-EL1.
*
+ * MDCR_EL3.NSPB (ARM v8.2): SPE enabled in non-secure state and
+ * disabled in secure state. Accesses to SPE registers at SEL1 generate
+ * trap exceptions to EL3.
+ *
* MDCR_EL3.TDOSA: Set to zero so that EL2 and EL2 System register
* access to the powerdown debug registers do not trap to EL3.
*
@@ -108,6 +112,19 @@
*/
mov_imm x0, ((MDCR_EL3_RESET_VAL | MDCR_SDD_BIT | MDCR_SPD32(MDCR_SPD32_DISABLE)) \
& ~(MDCR_TDOSA_BIT | MDCR_TDA_BIT | MDCR_TPM_BIT))
+
+#if ENABLE_SPE_FOR_LOWER_ELS
+ /* Detect if SPE is implemented */
+ mrs x1, id_aa64dfr0_el1
+ ubfx x1, x1, #ID_AA64DFR0_PMS_SHIFT, #ID_AA64DFR0_PMS_LENGTH
+ cmp x1, #0x1
+ b.ne 1f
+
+ /* Enable SPE for use by normal world */
+ orr x0, x0, #MDCR_NSPB(MDCR_NSPB_EL1)
+1:
+#endif
+
msr mdcr_el3, x0
/* ---------------------------------------------------------------------
diff --git a/include/lib/aarch64/arch.h b/include/lib/aarch64/arch.h
index 990c169..7bceea7 100644
--- a/include/lib/aarch64/arch.h
+++ b/include/lib/aarch64/arch.h
@@ -110,6 +110,11 @@
#define ID_AA64PFR0_EL3_SHIFT U(12)
#define ID_AA64PFR0_ELX_MASK U(0xf)
+/* ID_AA64DFR0_EL1.PMS definitions (for ARMv8.2+) */
+#define ID_AA64DFR0_PMS_SHIFT U(32)
+#define ID_AA64DFR0_PMS_LENGTH U(4)
+#define ID_AA64DFR0_PMS_MASK U(0xf)
+
#define EL_IMPL_NONE U(0)
#define EL_IMPL_A64ONLY U(1)
#define EL_IMPL_A64_A32 U(2)
@@ -189,6 +194,8 @@
#define MDCR_SPD32_DISABLE U(0x2)
#define MDCR_SPD32_ENABLE U(0x3)
#define MDCR_SDD_BIT (U(1) << 16)
+#define MDCR_NSPB(x) ((x) << 12)
+#define MDCR_NSPB_EL1 U(0x3)
#define MDCR_TDOSA_BIT (U(1) << 10)
#define MDCR_TDA_BIT (U(1) << 9)
#define MDCR_TPM_BIT (U(1) << 6)
@@ -199,6 +206,9 @@
#endif
/* MDCR_EL2 definitions */
+#define MDCR_EL2_TPMS (U(1) << 14)
+#define MDCR_EL2_E2PB(x) ((x) << 12)
+#define MDCR_EL2_E2PB_EL1 U(0x3)
#define MDCR_EL2_TDRA_BIT (U(1) << 11)
#define MDCR_EL2_TDOSA_BIT (U(1) << 10)
#define MDCR_EL2_TDA_BIT (U(1) << 9)
diff --git a/include/lib/aarch64/arch_helpers.h b/include/lib/aarch64/arch_helpers.h
index 32290e2..0d0d7d3 100644
--- a/include/lib/aarch64/arch_helpers.h
+++ b/include/lib/aarch64/arch_helpers.h
@@ -184,6 +184,7 @@
DEFINE_SYSREG_READ_FUNC(par_el1)
DEFINE_SYSREG_READ_FUNC(id_pfr1_el1)
DEFINE_SYSREG_READ_FUNC(id_aa64pfr0_el1)
+DEFINE_SYSREG_READ_FUNC(id_aa64dfr0_el1)
DEFINE_SYSREG_READ_FUNC(CurrentEl)
DEFINE_SYSREG_RW_FUNCS(daif)
DEFINE_SYSREG_RW_FUNCS(spsr_el1)
diff --git a/include/lib/el3_runtime/aarch64/context.h b/include/lib/el3_runtime/aarch64/context.h
index dead971..dcbf1c9 100644
--- a/include/lib/el3_runtime/aarch64/context.h
+++ b/include/lib/el3_runtime/aarch64/context.h
@@ -308,6 +308,7 @@
* Function prototypes
******************************************************************************/
void el1_sysregs_context_save(el1_sys_regs_t *regs);
+void el1_sysregs_context_save_post_ops(void);
void el1_sysregs_context_restore(el1_sys_regs_t *regs);
#if CTX_INCLUDE_FPREGS
void fpregs_context_save(fp_regs_t *regs);
diff --git a/include/plat/arm/common/plat_arm.h b/include/plat/arm/common/plat_arm.h
index e61c22f..3a73776 100644
--- a/include/plat/arm/common/plat_arm.h
+++ b/include/plat/arm/common/plat_arm.h
@@ -219,4 +219,7 @@
uint32_t cookie_lo,
void *handle);
+/* Disable Statistical Profiling Extensions helper */
+void arm_disable_spe(void);
+
#endif /* __PLAT_ARM_H__ */
diff --git a/lib/el3_runtime/aarch64/context.S b/lib/el3_runtime/aarch64/context.S
index afe912a..8a6c11b 100644
--- a/lib/el3_runtime/aarch64/context.S
+++ b/lib/el3_runtime/aarch64/context.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -9,6 +9,7 @@
#include <context.h>
.global el1_sysregs_context_save
+ .global el1_sysregs_context_save_post_ops
.global el1_sysregs_context_restore
#if CTX_INCLUDE_FPREGS
.global fpregs_context_save
@@ -111,6 +112,36 @@
/* -----------------------------------------------------
* The following function strictly follows the AArch64
* PCS to use x9-x17 (temporary caller-saved registers)
+ * to do post operations after saving the EL1 system
+ * register context.
+ * -----------------------------------------------------
+ */
+func el1_sysregs_context_save_post_ops
+#if ENABLE_SPE_FOR_LOWER_ELS
+ /* Detect if SPE is implemented */
+ mrs x9, id_aa64dfr0_el1
+ ubfx x9, x9, #ID_AA64DFR0_PMS_SHIFT, #ID_AA64DFR0_PMS_LENGTH
+ cmp x9, #0x1
+ b.ne 1f
+
+ /*
+ * Before switching from normal world to secure world
+ * the profiling buffers need to be drained out to memory. This is
+ * required to avoid an invalid memory access when TTBR is switched
+ * for entry to SEL1.
+ */
+ .arch armv8.2-a+profile
+ psb csync
+ dsb nsh
+ .arch armv8-a
+1:
+#endif
+ ret
+endfunc el1_sysregs_context_save_post_ops
+
+/* -----------------------------------------------------
+ * The following function strictly follows the AArch64
+ * PCS to use x9-x17 (temporary caller-saved registers)
* to restore EL1 system register context. It assumes
* that 'x0' is pointing to a 'el1_sys_regs' structure
* from where the register context will be restored
@@ -343,7 +374,7 @@
ldp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24]
ldp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26]
ldp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28]
- ldp x30, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
+ ldp x30, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
msr sp_el0, x17
ldp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16]
eret
diff --git a/lib/el3_runtime/aarch64/context_mgmt.c b/lib/el3_runtime/aarch64/context_mgmt.c
index 11ff163..5257bf1 100644
--- a/lib/el3_runtime/aarch64/context_mgmt.c
+++ b/lib/el3_runtime/aarch64/context_mgmt.c
@@ -218,7 +218,7 @@
******************************************************************************/
void cm_prepare_el3_exit(uint32_t security_state)
{
- uint32_t sctlr_elx, scr_el3;
+ uint32_t sctlr_elx, scr_el3, mdcr_el2;
cpu_context_t *ctx = cm_get_context(security_state);
assert(ctx);
@@ -315,6 +315,13 @@
* relying on hw. Some fields are architecturally
* UNKNOWN on reset.
*
+ * MDCR_EL2.TPMS (ARM v8.2): Do not trap statistical
+ * profiling controls to EL2.
+ *
+ * MDCR_EL2.E2PB (ARM v8.2): SPE enabled in non-secure
+ * state. Accesses to profiling buffer controls at
+ * non-secure EL1 are not trapped to EL2.
+ *
* MDCR_EL2.TDRA: Set to zero so that Non-secure EL0 and
* EL1 System register accesses to the Debug ROM
* registers are not trapped to EL2.
@@ -343,13 +350,32 @@
* MDCR_EL2.HPMN: Set to value of PMCR_EL0.N which is the
* architecturally-defined reset value.
*/
- write_mdcr_el2((MDCR_EL2_RESET_VAL |
+ mdcr_el2 = ((MDCR_EL2_RESET_VAL |
((read_pmcr_el0() & PMCR_EL0_N_BITS)
>> PMCR_EL0_N_SHIFT)) &
~(MDCR_EL2_TDRA_BIT | MDCR_EL2_TDOSA_BIT
| MDCR_EL2_TDA_BIT | MDCR_EL2_TDE_BIT
| MDCR_EL2_HPME_BIT | MDCR_EL2_TPM_BIT
| MDCR_EL2_TPMCR_BIT));
+
+#if ENABLE_SPE_FOR_LOWER_ELS
+ uint64_t id_aa64dfr0_el1;
+
+ /* Detect if SPE is implemented */
+ id_aa64dfr0_el1 = read_id_aa64dfr0_el1() >>
+ ID_AA64DFR0_PMS_SHIFT;
+ if ((id_aa64dfr0_el1 & ID_AA64DFR0_PMS_MASK) == 1) {
+ /*
+ * Make sure traps to EL2 are not generated if
+ * EL2 is implemented but not used.
+ */
+ mdcr_el2 &= ~MDCR_EL2_TPMS;
+ mdcr_el2 |= MDCR_EL2_E2PB(MDCR_EL2_E2PB_EL1);
+ }
+#endif
+
+ write_mdcr_el2(mdcr_el2);
+
/*
* Initialise HSTR_EL2. All fields are architecturally
* UNKNOWN on reset.
@@ -389,6 +415,7 @@
assert(ctx);
el1_sysregs_context_save(get_sysregs_ctx(ctx));
+ el1_sysregs_context_save_post_ops();
}
void cm_el1_sysregs_context_restore(uint32_t security_state)
diff --git a/make_helpers/defaults.mk b/make_helpers/defaults.mk
index 2c8f82a..9946fea 100644
--- a/make_helpers/defaults.mk
+++ b/make_helpers/defaults.mk
@@ -136,3 +136,20 @@
# required to enable cache coherency after warm reset (eg: single cluster
# platforms).
WARMBOOT_ENABLE_DCACHE_EARLY := 0
+
+# By default, enable Statistical Profiling Extensions.
+# The top level Makefile will disable this feature depending on
+# the target architecture and version number.
+ENABLE_SPE_FOR_LOWER_ELS := 1
+
+# SPE is enabled by default but only supported on AArch64 8.2 onwards.
+# Disable it in all other cases.
+ifeq (${ARCH},aarch32)
+ override ENABLE_SPE_FOR_LOWER_ELS := 0
+else
+ ifeq (${ARM_ARCH_MAJOR},8)
+ ifeq ($(ARM_ARCH_MINOR),$(filter $(ARM_ARCH_MINOR),0 1))
+ ENABLE_SPE_FOR_LOWER_ELS := 0
+ endif
+ endif
+endif
diff --git a/plat/arm/board/fvp/fvp_pm.c b/plat/arm/board/fvp/fvp_pm.c
index f4df658..e39a4d5 100644
--- a/plat/arm/board/fvp/fvp_pm.c
+++ b/plat/arm/board/fvp/fvp_pm.c
@@ -48,6 +48,14 @@
{
uint64_t mpidr = read_mpidr_el1();
+#if ENABLE_SPE_FOR_LOWER_ELS
+ /*
+ * On power down we need to disable statistical profiling extensions
+ * before exiting coherency.
+ */
+ arm_disable_spe();
+#endif
+
/* Disable coherency if this cluster is to be turned off */
fvp_interconnect_disable();
diff --git a/plat/arm/common/aarch64/arm_helpers.S b/plat/arm/common/aarch64/arm_helpers.S
index 1f20cb5..86565f5 100644
--- a/plat/arm/common/aarch64/arm_helpers.S
+++ b/plat/arm/common/aarch64/arm_helpers.S
@@ -12,6 +12,7 @@
.globl plat_crash_console_putc
.globl plat_crash_console_flush
.globl platform_mem_init
+ .globl arm_disable_spe
/* -----------------------------------------------------
@@ -86,3 +87,31 @@
func platform_mem_init
ret
endfunc platform_mem_init
+
+ /* -----------------------------------------------------
+ * void arm_disable_spe (void);
+ * -----------------------------------------------------
+ */
+#if ENABLE_SPE_FOR_LOWER_ELS
+func arm_disable_spe
+ /* Detect if SPE is implemented */
+ mrs x0, id_aa64dfr0_el1
+ ubfx x0, x0, #ID_AA64DFR0_PMS_SHIFT, #ID_AA64DFR0_PMS_LENGTH
+ cmp x0, #0x1
+ b.ne 1f
+
+ /* Drain buffered data */
+ .arch armv8.2-a+profile
+ psb csync
+ dsb nsh
+
+ /* Disable Profiling Buffer */
+ mrs x0, pmblimitr_el1
+ bic x0, x0, #1
+ msr pmblimitr_el1, x0
+ isb
+ .arch armv8-a
+1:
+ ret
+endfunc arm_disable_spe
+#endif