Merge "AArch64: Disable Secure Cycle Counter" into integration

bl1/aarch64/bl1_exceptions.S

 /*
- * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -223,6 +223,14 @@ smc_handler:
 	 */
 	bl	save_gp_registers
 
+	/* -----------------------------------------------------
+	 * If Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented, save PMCR_EL0 and
+	 * disable all event counters and cycle counter.
+	 * -----------------------------------------------------
+	 */
+	bl	save_pmcr_disable_pmu
+
 	/* -----------------------------------------------------
 	 * Populate the parameters for the SMC handler. We
 	 * already have x0-x4 in place. x5 will point to a

bl31/aarch64/ea_delegate.S

@@ -68,6 +68,13 @@ func enter_lower_el_sync_ea
 	/* Save GP registers */
 	bl	save_gp_registers
 
+	/*
+	 * If Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented, save PMCR_EL0 and
+	 * disable all event counters and cycle counter.
+	 */
+	bl	save_pmcr_disable_pmu
+
 	/* Save ARMv8.3-PAuth registers and load firmware key */
 #if CTX_INCLUDE_PAUTH_REGS
 	bl	pauth_context_save
@@ -106,6 +113,13 @@ func enter_lower_el_async_ea
 	/* Save GP registers */
 	bl	save_gp_registers
 
+	/*
+	 * If Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented, save PMCR_EL0 and
+	 * disable all event counters and cycle counter.
+	 */
+	bl	save_pmcr_disable_pmu
+
 	/* Save ARMv8.3-PAuth registers and load firmware key */
 #if CTX_INCLUDE_PAUTH_REGS
 	bl	pauth_context_save

bl31/aarch64/runtime_exceptions.S

@@ -67,6 +67,14 @@
 
 	/* Save GP registers and restore them afterwards */
 	bl	save_gp_registers
+
+	/*
+	 * If Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented, save PMCR_EL0 and
+	 * disable all event counters and cycle counter.
+	 */
+	bl	save_pmcr_disable_pmu
+
 	bl	handle_lower_el_ea_esb
 	bl	restore_gp_registers
 
@@ -123,6 +131,13 @@
 
 	bl	save_gp_registers
 
+	/*
+	 * If Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented, save PMCR_EL0 and
+	 * disable all event counters and cycle counter.
+	 */
+	bl	save_pmcr_disable_pmu
+
 	/* Save ARMv8.3-PAuth registers and load firmware key */
 #if CTX_INCLUDE_PAUTH_REGS
 	bl	pauth_context_save
@@ -335,6 +350,13 @@ smc_handler64:
 	/* Save general purpose registers */
 	bl	save_gp_registers
 
+	/*
+	 * If Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented, save PMCR_EL0 and
+	 * disable all event counters and cycle counter.
+	 */
+	bl	save_pmcr_disable_pmu
+
 	/* Save ARMv8.3-PAuth registers and load firmware key */
 #if CTX_INCLUDE_PAUTH_REGS
 	bl	pauth_context_save

include/arch/aarch64/arch.h

@@ -133,12 +133,13 @@
 #define ID_AA64PFR0_EL2_SHIFT	U(8)
 #define ID_AA64PFR0_EL3_SHIFT	U(12)
 #define ID_AA64PFR0_AMU_SHIFT	U(44)
-#define ID_AA64PFR0_AMU_LENGTH	U(4)
 #define ID_AA64PFR0_AMU_MASK	ULL(0xf)
 #define ID_AA64PFR0_ELX_MASK	ULL(0xf)
+#define ID_AA64PFR0_GIC_SHIFT	U(24)
+#define ID_AA64PFR0_GIC_WIDTH	U(4)
+#define ID_AA64PFR0_GIC_MASK	ULL(0xf)
 #define ID_AA64PFR0_SVE_SHIFT	U(32)
 #define ID_AA64PFR0_SVE_MASK	ULL(0xf)
-#define ID_AA64PFR0_SVE_LENGTH	U(4)
 #define ID_AA64PFR0_MPAM_SHIFT	U(40)
 #define ID_AA64PFR0_MPAM_MASK	ULL(0xf)
 #define ID_AA64PFR0_DIT_SHIFT	U(48)
@@ -149,18 +150,14 @@
 #define ID_AA64PFR0_CSV2_MASK	ULL(0xf)
 #define ID_AA64PFR0_CSV2_LENGTH	U(4)
 
-/* 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	ULL(0xf)
-
+/* Exception level handling */
 #define EL_IMPL_NONE		ULL(0)
 #define EL_IMPL_A64ONLY		ULL(1)
 #define EL_IMPL_A64_A32		ULL(2)
 
-#define ID_AA64PFR0_GIC_SHIFT	U(24)
-#define ID_AA64PFR0_GIC_WIDTH	U(4)
-#define ID_AA64PFR0_GIC_MASK	ULL(0xf)
+/* ID_AA64DFR0_EL1.PMS definitions (for ARMv8.2+) */
+#define ID_AA64DFR0_PMS_SHIFT	U(32)
+#define ID_AA64DFR0_PMS_MASK	ULL(0xf)
 
 /* ID_AA64ISAR1_EL1 definitions */
 #define ID_AA64ISAR1_EL1	S3_0_C0_C6_1
@@ -305,20 +302,25 @@
 #define SCR_RESET_VAL		SCR_RES1_BITS
 
 /* MDCR_EL3 definitions */
+#define MDCR_SCCD_BIT		(ULL(1) << 23)
+#define MDCR_SPME_BIT		(ULL(1) << 17)
+#define MDCR_SDD_BIT		(ULL(1) << 16)
 #define MDCR_SPD32(x)		((x) << 14)
 #define MDCR_SPD32_LEGACY	ULL(0x0)
 #define MDCR_SPD32_DISABLE	ULL(0x2)
 #define MDCR_SPD32_ENABLE	ULL(0x3)
-#define MDCR_SDD_BIT		(ULL(1) << 16)
 #define MDCR_NSPB(x)		((x) << 12)
 #define MDCR_NSPB_EL1		ULL(0x3)
 #define MDCR_TDOSA_BIT		(ULL(1) << 10)
 #define MDCR_TDA_BIT		(ULL(1) << 9)
 #define MDCR_TPM_BIT		(ULL(1) << 6)
-#define MDCR_SCCD_BIT		(ULL(1) << 23)
 #define MDCR_EL3_RESET_VAL	ULL(0x0)
 
 /* MDCR_EL2 definitions */
+#define MDCR_EL2_HLP		(U(1) << 26)
+#define MDCR_EL2_HCCD		(U(1) << 23)
+#define MDCR_EL2_TTRF		(U(1) << 19)
+#define MDCR_EL2_HPMD		(U(1) << 17)
 #define MDCR_EL2_TPMS		(U(1) << 14)
 #define MDCR_EL2_E2PB(x)	((x) << 12)
 #define MDCR_EL2_E2PB_EL1	U(0x3)
@@ -678,10 +680,14 @@
 #define PMCR_EL0_N_SHIFT	U(11)
 #define PMCR_EL0_N_MASK		U(0x1f)
 #define PMCR_EL0_N_BITS		(PMCR_EL0_N_MASK << PMCR_EL0_N_SHIFT)
+#define PMCR_EL0_LP_BIT		(U(1) << 7)
 #define PMCR_EL0_LC_BIT		(U(1) << 6)
 #define PMCR_EL0_DP_BIT		(U(1) << 5)
 #define PMCR_EL0_X_BIT		(U(1) << 4)
 #define PMCR_EL0_D_BIT		(U(1) << 3)
+#define PMCR_EL0_C_BIT		(U(1) << 2)
+#define PMCR_EL0_P_BIT		(U(1) << 1)
+#define PMCR_EL0_E_BIT		(U(1) << 0)
 
 /*******************************************************************************
  * Definitions for system register interface to SVE

include/arch/aarch64/el3_common_macros.S

@@ -116,11 +116,41 @@
 	 * ---------------------------------------------------------------------
 	 */
 	mov_imm	x0, ((MDCR_EL3_RESET_VAL | MDCR_SDD_BIT | \
-		      MDCR_SPD32(MDCR_SPD32_DISABLE) | MDCR_SCCD_BIT) \
-		    & ~(MDCR_TDOSA_BIT | MDCR_TDA_BIT | MDCR_TPM_BIT))
+		      MDCR_SPD32(MDCR_SPD32_DISABLE) | MDCR_SCCD_BIT) & \
+		    ~(MDCR_TDOSA_BIT | MDCR_TDA_BIT | MDCR_TPM_BIT))
 
 	msr	mdcr_el3, x0
 
+	/* ---------------------------------------------------------------------
+	 * Initialise PMCR_EL0 setting all fields rather than relying
+	 * on hw. Some fields are architecturally UNKNOWN on reset.
+	 *
+	 * PMCR_EL0.LP: Set to one so that event counter overflow, that
+	 *  is recorded in PMOVSCLR_EL0[0-30], occurs on the increment
+	 *  that changes PMEVCNTR<n>_EL0[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.
+	 *
+	 * PMCR_EL0.LC: Set to one so that cycle counter overflow, that
+	 *  is recorded in PMOVSCLR_EL0[31], occurs on the increment
+	 *  that changes PMCCNTR_EL0[63] from 1 to 0.
+	 *
+	 * PMCR_EL0.DP: Set to one so that the cycle counter,
+	 *  PMCCNTR_EL0 does not count when event counting is prohibited.
+	 *
+	 * PMCR_EL0.X: Set to zero to disable export of events.
+	 *
+	 * PMCR_EL0.D: Set to zero so that, when enabled, PMCCNTR_EL0
+	 *  counts on every clock cycle.
+	 * ---------------------------------------------------------------------
+	 */
+	mov_imm	x0, ((PMCR_EL0_RESET_VAL | PMCR_EL0_LP_BIT | \
+		      PMCR_EL0_LC_BIT | PMCR_EL0_DP_BIT) & \
+		    ~(PMCR_EL0_X_BIT | PMCR_EL0_D_BIT))
+
+	msr	pmcr_el0, x0
+
 	/* ---------------------------------------------------------------------
 	 * Enable External Aborts and SError Interrupts now that the exception
 	 * vectors have been setup.

include/lib/el3_runtime/aarch64/context.h

@@ -59,7 +59,7 @@
 #define CTX_RUNTIME_SP		U(0x10)
 #define CTX_SPSR_EL3		U(0x18)
 #define CTX_ELR_EL3		U(0x20)
-#define CTX_UNUSED		U(0x28)
+#define CTX_PMCR_EL0		U(0x28)
 #define CTX_EL3STATE_END	U(0x30)
 
 /*******************************************************************************
@@ -91,22 +91,21 @@
 #define CTX_AFSR1_EL1		U(0x98)
 #define CTX_CONTEXTIDR_EL1	U(0xa0)
 #define CTX_VBAR_EL1		U(0xa8)
-#define CTX_PMCR_EL0		U(0xb0)
 
 /*
  * If the platform is AArch64-only, there is no need to save and restore these
  * AArch32 registers.
  */
 #if CTX_INCLUDE_AARCH32_REGS
-#define CTX_SPSR_ABT		U(0xc0)  /* Align to the next 16 byte boundary */
-#define CTX_SPSR_UND		U(0xc8)
-#define CTX_SPSR_IRQ		U(0xd0)
-#define CTX_SPSR_FIQ		U(0xd8)
-#define CTX_DACR32_EL2		U(0xe0)
-#define CTX_IFSR32_EL2		U(0xe8)
-#define CTX_AARCH32_END		U(0xf0) /* Align to the next 16 byte boundary */
+#define CTX_SPSR_ABT		U(0xb0)	/* Align to the next 16 byte boundary */
+#define CTX_SPSR_UND		U(0xb8)
+#define CTX_SPSR_IRQ		U(0xc0)
+#define CTX_SPSR_FIQ		U(0xc8)
+#define CTX_DACR32_EL2		U(0xd0)
+#define CTX_IFSR32_EL2		U(0xd8)
+#define CTX_AARCH32_END		U(0xe0) /* Align to the next 16 byte boundary */
 #else
-#define CTX_AARCH32_END		U(0xc0)  /* Align to the next 16 byte boundary */
+#define CTX_AARCH32_END		U(0xb0)	/* Align to the next 16 byte boundary */
 #endif /* CTX_INCLUDE_AARCH32_REGS */
 
 /*

lib/el3_runtime/aarch64/context.S

@@ -24,8 +24,44 @@
 	.global	save_gp_registers
 	.global	restore_gp_registers
 	.global	restore_gp_registers_eret
+	.global	save_pmcr_disable_pmu
 	.global	el3_exit
 
+/* -----------------------------------------------------
+ * If ARMv8.5-PMU is implemented, cycle counting is
+ * disabled by seting MDCR_EL3.SCCD to 1.
+ * -----------------------------------------------------
+ */
+func save_pmcr_disable_pmu
+	/* -----------------------------------------------------
+	 * Check if earlier initialization MDCR_EL3.SCCD to 1
+	 * failed, meaning that ARMv8-PMU is not implemented and
+	 * PMCR_EL0 should be saved in non-secure context.
+	 * -----------------------------------------------------
+	 */
+	mrs	x9, mdcr_el3
+	tst	x9, #MDCR_SCCD_BIT
+	bne	1f
+
+	/* Secure Cycle Counter is not disabled */
+	mrs	x9, pmcr_el0
+
+	/* Check caller's security state */
+	mrs	x10, scr_el3
+	tst	x10, #SCR_NS_BIT
+	beq	2f
+
+	/* Save PMCR_EL0 if called from Non-secure state */
+	str	x9, [sp, #CTX_EL3STATE_OFFSET + CTX_PMCR_EL0]
+
+	/* Disable cycle counter when event counting is prohibited */
+2:	orr	x9, x9, #PMCR_EL0_DP_BIT
+	msr	pmcr_el0, x9
+
+	isb
+1:	ret
+endfunc save_pmcr_disable_pmu
+
 /* -----------------------------------------------------
  * The following function strictly follows the AArch64
  * PCS to use x9-x17 (temporary caller-saved registers)
@@ -80,9 +116,6 @@ func el1_sysregs_context_save
 	mrs	x9, vbar_el1
 	stp	x17, x9, [x0, #CTX_CONTEXTIDR_EL1]
 
-	mrs	x10, pmcr_el0
-	str	x10, [x0, #CTX_PMCR_EL0]
-
 	/* Save AArch32 system registers if the build has instructed so */
 #if CTX_INCLUDE_AARCH32_REGS
 	mrs	x11, spsr_abt
@@ -169,9 +202,6 @@ func el1_sysregs_context_restore
 	msr	contextidr_el1, x17
 	msr	vbar_el1, x9
 
-	ldr	x10, [x0, #CTX_PMCR_EL0]
-	msr	pmcr_el0, x10
-
 	/* Restore AArch32 system registers if the build has instructed so */
 #if CTX_INCLUDE_AARCH32_REGS
 	ldp	x11, x12, [x0, #CTX_SPSR_ABT]
@@ -503,6 +533,29 @@ func el3_exit
 	msr	spsr_el3, x16
 	msr	elr_el3, x17
 
+	/* -----------------------------------------------------
+	 * Restore PMCR_EL0 when returning to Non-secure state
+	 * if Secure Cycle Counter is not disabled in MDCR_EL3
+	 * when ARMv8.5-PMU is implemented
+	 * -----------------------------------------------------
+	 */
+	tst	x18, #SCR_NS_BIT
+	beq	2f
+
+	/* -----------------------------------------------------
+	 * Back to Non-secure state.
+	 * Check if earlier initialization MDCR_EL3.SCCD to 1
+	 * failed, meaning that ARMv8-PMU is not implemented and
+	 * PMCR_EL0 should be restored from non-secure context.
+	 * -----------------------------------------------------
+	 */
+	mrs	x17, mdcr_el3
+	tst	x17, #MDCR_SCCD_BIT
+	bne	2f
+	ldr	x17, [sp, #CTX_EL3STATE_OFFSET + CTX_PMCR_EL0]
+	msr	pmcr_el0, x17
+2:
+
 #if IMAGE_BL31 && DYNAMIC_WORKAROUND_CVE_2018_3639
 	/* Restore mitigation state as it was on entry to EL3 */
 	ldr	x17, [sp, #CTX_CVE_2018_3639_OFFSET + CTX_CVE_2018_3639_DISABLE]

lib/el3_runtime/aarch64/context_mgmt.c

@@ -66,7 +66,7 @@ void __init cm_init(void)
 void cm_setup_context(cpu_context_t *ctx, const entry_point_info_t *ep)
 {
 	unsigned int security_state;
-	uint32_t scr_el3, pmcr_el0;
+	uint32_t scr_el3;
 	el3_state_t *state;
 	gp_regs_t *gp_regs;
 	unsigned long sctlr_elx, actlr_elx;
@@ -225,31 +225,10 @@ void cm_setup_context(cpu_context_t *ctx, const entry_point_info_t *ep)
 	actlr_elx = read_actlr_el1();
 	write_ctx_reg((get_sysregs_ctx(ctx)), (CTX_ACTLR_EL1), (actlr_elx));
 
-	if (security_state == SECURE) {
 	/*
-		 * Initialise PMCR_EL0 for secure context only, setting all
-		 * fields rather than relying on hw. Some fields are
-		 * architecturally UNKNOWN on reset.
-		 *
-		 * PMCR_EL0.LC: Set to one so that cycle counter overflow, that
-		 *  is recorded in PMOVSCLR_EL0[31], occurs on the increment
-		 *  that changes PMCCNTR_EL0[63] from 1 to 0.
-		 *
-		 * PMCR_EL0.DP: Set to one so that the cycle counter,
-		 *  PMCCNTR_EL0 does not count when event counting is prohibited.
-		 *
-		 * PMCR_EL0.X: Set to zero to disable export of events.
-		 *
-		 * PMCR_EL0.D: Set to zero so that, when enabled, PMCCNTR_EL0
-		 *  counts on every clock cycle.
+	 * Populate EL3 state so that we've the right context
+	 * before doing ERET
 	 */
-		pmcr_el0 = ((PMCR_EL0_RESET_VAL | PMCR_EL0_LC_BIT
-				| PMCR_EL0_DP_BIT)
-				& ~(PMCR_EL0_X_BIT | PMCR_EL0_D_BIT));
-		write_ctx_reg(get_sysregs_ctx(ctx), CTX_PMCR_EL0, pmcr_el0);
-	}
-
-	/* Populate EL3 state so that we've the right context before doing ERET */
 	state = get_el3state_ctx(ctx);
 	write_ctx_reg(state, CTX_SCR_EL3, scr_el3);
 	write_ctx_reg(state, CTX_ELR_EL3, ep->pc);
@@ -441,6 +420,29 @@ void cm_prepare_el3_exit(uint32_t security_state)
 			 * relying on hw. Some fields are architecturally
 			 * UNKNOWN on reset.
 			 *
+			 * MDCR_EL2.HLP: Set to one so that event counter
+			 *  overflow, that is recorded in PMOVSCLR_EL0[0-30],
+			 *  occurs on the increment that changes
+			 *  PMEVCNTR<n>_EL0[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.
+			 *
+			 * MDCR_EL2.TTRF: Set to zero so that access to Trace
+			 *  Filter Control register TRFCR_EL1 at EL1 is not
+			 *  trapped to EL2. This bit is RES0 in versions of
+			 *  the architecture earlier than ARMv8.4.
+			 *
+			 * MDCR_EL2.HPMD: Set to one so that event counting is
+			 *  prohibited at EL2. This bit is RES0 in versions of
+			 *  the architecture earlier than ARMv8.1, setting it
+			 *  to 1 doesn't have any effect on them.
+			 *
+			 * MDCR_EL2.TPMS: Set to zero so that accesses to
+			 *  Statistical Profiling control registers from EL1
+			 *  do not trap to EL2. This bit is RES0 when SPE is
+			 *  not implemented.
+			 *
 			 * 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.
@@ -469,13 +471,15 @@ void cm_prepare_el3_exit(uint32_t security_state)
 			 * MDCR_EL2.HPMN: Set to value of PMCR_EL0.N which is the
 			 *  architecturally-defined reset value.
 			 */
-			mdcr_el2 = ((MDCR_EL2_RESET_VAL |
+			mdcr_el2 = ((MDCR_EL2_RESET_VAL | MDCR_EL2_HLP |
+				     MDCR_EL2_HPMD) |
 				   ((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));
+				   ~(MDCR_EL2_TTRF | MDCR_EL2_TPMS |
+				     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);
 
 			write_mdcr_el2(mdcr_el2);