Initialise CPU contexts from entry_point_info

Consolidate all BL3-1 CPU context initialization for cold boot, PSCI
and SPDs into two functions:
*  The first uses entry_point_info to initialize the relevant
   cpu_context for first entry into a lower exception level on a CPU
*  The second populates the EL1 and EL2 system registers as needed
   from the cpu_context to ensure correct entry into the lower EL

This patch alters the way that BL3-1 determines which exception level
is used when first entering EL1 or EL2 during cold boot - this is now
fully determined by the SPSR value in the entry_point_info for BL3-3,
as set up by the platform code in BL2 (or otherwise provided to BL3-1).

In the situation that EL1 (or svc mode) is selected for a processor
that supports EL2, the context management code will now configure all
essential EL2 register state to ensure correct execution of EL1. This
allows the platform code to run non-secure EL1 payloads directly
without requiring a small EL2 stub or OS loader.

Change-Id: If9fbb2417e82d2226e47568203d5a369f39d3b0f

bl1/aarch64/bl1_arch_setup.c

@@ -46,11 +46,10 @@ void bl1_arch_setup(void)
 	isb();
 
 	/*
-	 * Enable HVCs, route FIQs to EL3, set the next EL to be AArch64, route
-	 * external abort and SError interrupts to EL3
+	 * Set the next EL to be AArch64, route external abort and SError
+	 * interrupts to EL3
 	 */
-	tmp_reg = SCR_RES1_BITS | SCR_RW_BIT | SCR_HCE_BIT | SCR_EA_BIT |
-		  SCR_FIQ_BIT;
+	tmp_reg = SCR_RES1_BITS | SCR_RW_BIT | SCR_EA_BIT;
 	write_scr(tmp_reg);
 
 	/*

bl31/aarch64/bl31_arch_setup.c

@@ -51,11 +51,11 @@ void bl31_arch_setup(void)
 	write_sctlr_el3(tmp_reg);
 
 	/*
-	 * Enable HVCs, route FIQs to EL3, set the next EL to be AArch64, route
-	 * external abort and SError interrupts to EL3
+	 * Route external abort and SError interrupts to EL3
+	 * other SCR bits will be configured before exiting to a lower exception
+	 * level
 	 */
-	tmp_reg = SCR_RES1_BITS | SCR_RW_BIT | SCR_HCE_BIT | SCR_EA_BIT |
-		  SCR_FIQ_BIT;
+	tmp_reg = SCR_RES1_BITS | SCR_EA_BIT;
 	write_scr(tmp_reg);
 
 	/*
@@ -68,39 +68,3 @@ void bl31_arch_setup(void)
 	counter_freq = plat_get_syscnt_freq();
 	write_cntfrq_el0(counter_freq);
 }
-
-/*******************************************************************************
- * Detect what the security state of the next EL is and setup the minimum
- * required architectural state: program SCTRL to reflect the RES1 bits, and to
- * have MMU and caches disabled
- ******************************************************************************/
-void bl31_next_el_arch_setup(uint32_t security_state)
-{
-	unsigned long id_aa64pfr0 = read_id_aa64pfr0_el1();
-	unsigned long next_sctlr;
-	unsigned long el_status;
-	unsigned long scr = read_scr();
-
-	/* Use the same endianness than the current BL */
-	next_sctlr = (read_sctlr_el3() & SCTLR_EE_BIT);
-
-	/* Find out which EL we are going to */
-	el_status = (id_aa64pfr0 >> ID_AA64PFR0_EL2_SHIFT) & ID_AA64PFR0_ELX_MASK;
-
-	if (security_state == NON_SECURE) {
-		/* Check if EL2 is supported */
-		if (el_status && (scr & SCR_HCE_BIT)) {
-			/* Set SCTLR EL2 */
-			next_sctlr |= SCTLR_EL2_RES1;
-			write_sctlr_el2(next_sctlr);
-			return;
-		}
-	}
-
-	/*
-	 * SCTLR_EL1 needs the same programming irrespective of the
-	 * security state of EL1.
-	 */
-	next_sctlr |= SCTLR_EL1_RES1;
-	write_sctlr_el1(next_sctlr);
-}

bl31/aarch64/context.S

@@ -43,9 +43,8 @@
 	.global el3_sysregs_context_save
 func el3_sysregs_context_save
 
-	mrs	x9, scr_el3
 	mrs	x10, sctlr_el3
-	stp	x9, x10, [x0, #CTX_SCR_EL3]
+	str	x10, [x0, #CTX_SCTLR_EL3]
 
 	mrs	x11, cptr_el3
 	stp	x11, xzr, [x0, #CTX_CPTR_EL3]
@@ -98,8 +97,7 @@ func el3_sysregs_context_restore
 	/* Make sure all the above changes are observed */
 	isb
 
-	ldp	x9, x10, [x0, #CTX_SCR_EL3]
-	msr	scr_el3, x9
+	ldr	x10, [x0, #CTX_SCTLR_EL3]
 	msr	sctlr_el3, x10
 	isb
 

bl31/bl31_main.c

@@ -140,53 +140,18 @@ uint32_t bl31_get_next_image_type(void)
 void bl31_prepare_next_image_entry()
 {
 	entry_point_info_t *next_image_info;
-	uint32_t scr, image_type;
-	cpu_context_t *ctx;
-	gp_regs_t *gp_regs;
+	uint32_t image_type;
 
 	/* Determine which image to execute next */
 	image_type = bl31_get_next_image_type();
 
-	/*
-	 * Setup minimal architectural state of the next highest EL to
-	 * allow execution in it immediately upon entering it.
-	 */
-	bl31_next_el_arch_setup(image_type);
-
 	/* Program EL3 registers to enable entry into the next EL */
 	next_image_info = bl31_plat_get_next_image_ep_info(image_type);
 	assert(next_image_info);
 	assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr));
 
-	scr = read_scr();
-	scr &= ~SCR_NS_BIT;
-	if (image_type == NON_SECURE)
-		scr |= SCR_NS_BIT;
-
-	scr &= ~SCR_RW_BIT;
-	if ((next_image_info->spsr & (1 << MODE_RW_SHIFT)) ==
-				(MODE_RW_64 << MODE_RW_SHIFT))
-		scr |= SCR_RW_BIT;
-
-	/*
-	 * Tell the context mgmt. library to ensure that SP_EL3 points to
-	 * the right context to exit from EL3 correctly.
-	 */
-	cm_set_el3_eret_context(image_type,
-			next_image_info->pc,
-			next_image_info->spsr,
-			scr);
-
-	/*
-	 * Save the args generated in BL2 for the image in the right context
-	 * used on its entry
-	 */
-	ctx = cm_get_context(image_type);
-	gp_regs = get_gpregs_ctx(ctx);
-	memcpy(gp_regs, (void *)&next_image_info->args, sizeof(aapcs64_params_t));
-
-	/* Finally set the next context */
-	cm_set_next_eret_context(image_type);
+	cm_init_context(read_mpidr_el1(), next_image_info);
+	cm_prepare_el3_exit(image_type);
 }
 
 /*******************************************************************************

bl31/context_mgmt.c

@@ -40,6 +40,7 @@
 #include <platform.h>
 #include <platform_def.h>
 #include <runtime_svc.h>
+#include <string.h>
 
 
 /*******************************************************************************
@@ -86,6 +87,177 @@ void cm_set_context_by_mpidr(uint64_t mpidr, void *context, uint32_t security_st
 	set_cpu_data_by_mpidr(mpidr, cpu_context[security_state], context);
 }
 
+/*******************************************************************************
+ * This function is used to program the context that's used for exception
+ * return. This initializes the SP_EL3 to a pointer to a 'cpu_context' set for
+ * the required security state
+ ******************************************************************************/
+static inline void cm_set_next_context(void *context)
+{
+#if DEBUG
+	uint64_t sp_mode;
+
+	/*
+	 * Check that this function is called with SP_EL0 as the stack
+	 * pointer
+	 */
+	__asm__ volatile("mrs	%0, SPSel\n"
+			 : "=r" (sp_mode));
+
+	assert(sp_mode == MODE_SP_EL0);
+#endif
+
+	__asm__ volatile("msr	spsel, #1\n"
+			 "mov	sp, %0\n"
+			 "msr	spsel, #0\n"
+			 : : "r" (context));
+}
+
+/*******************************************************************************
+ * The following function initializes a cpu_context for the current CPU for
+ * first use, and sets the initial entrypoint state as specified by the
+ * entry_point_info structure.
+ *
+ * The security state to initialize is determined by the SECURE attribute
+ * of the entry_point_info. The function returns a pointer to the initialized
+ * context and sets this as the next context to return to.
+ *
+ * The EE and ST attributes are used to configure the endianess and secure
+ * timer availability for the new excution context.
+ *
+ * To prepare the register state for entry call cm_prepare_el3_exit() and
+ * el3_exit(). For Secure-EL1 cm_prepare_el3_exit() is equivalent to
+ * cm_e1_sysreg_context_restore().
+ ******************************************************************************/
+void cm_init_context(uint64_t mpidr, const entry_point_info_t *ep)
+{
+	uint32_t security_state;
+	cpu_context_t *ctx;
+	uint32_t scr_el3;
+	el3_state_t *state;
+	gp_regs_t *gp_regs;
+	unsigned long sctlr_elx;
+
+	security_state = GET_SECURITY_STATE(ep->h.attr);
+	ctx = cm_get_context_by_mpidr(mpidr, security_state);
+	assert(ctx);
+
+	/* Clear any residual register values from the context */
+	memset(ctx, 0, sizeof(*ctx));
+
+	/*
+	 * Base the context SCR on the current value, adjust for entry point
+	 * specific requirements and set trap bits from the IMF
+	 * TODO: provide the base/global SCR bits using another mechanism?
+	 */
+	scr_el3 = read_scr();
+	scr_el3 &= ~(SCR_NS_BIT | SCR_RW_BIT | SCR_FIQ_BIT | SCR_IRQ_BIT |
+			SCR_ST_BIT | SCR_HCE_BIT);
+
+	if (security_state != SECURE)
+		scr_el3 |= SCR_NS_BIT;
+
+	if (GET_RW(ep->spsr) == MODE_RW_64)
+		scr_el3 |= SCR_RW_BIT;
+
+	if (EP_GET_ST(ep->h.attr))
+		scr_el3 |= SCR_ST_BIT;
+
+	scr_el3 |= get_scr_el3_from_routing_model(security_state);
+
+	/*
+	 * Set up SCTLR_ELx for the target exception level:
+	 * EE bit is taken from the entrpoint attributes
+	 * M, C and I bits must be zero (as required by PSCI specification)
+	 *
+	 * The target exception level is based on the spsr mode requested.
+	 * If execution is requested to EL2 or hyp mode, HVC is enabled
+	 * via SCR_EL3.HCE.
+	 *
+	 * Always compute the SCTLR_EL1 value and save in the cpu_context
+	 * - the EL2 registers are set up by cm_preapre_ns_entry() as they
+	 * are not part of the stored cpu_context
+	 *
+	 * TODO: In debug builds the spsr should be validated and checked
+	 * against the CPU support, security state, endianess and pc
+	 */
+	sctlr_elx = EP_GET_EE(ep->h.attr) ? SCTLR_EE_BIT : 0;
+	sctlr_elx |= SCTLR_EL1_RES1;
+	write_ctx_reg(get_sysregs_ctx(ctx), CTX_SCTLR_EL1, sctlr_elx);
+
+	if ((GET_RW(ep->spsr) == MODE_RW_64
+	     && GET_EL(ep->spsr) == MODE_EL2)
+	    || (GET_RW(ep->spsr) != MODE_RW_64
+		&& GET_M32(ep->spsr) == MODE32_hyp)) {
+		scr_el3 |= SCR_HCE_BIT;
+	}
+
+	/* 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);
+	write_ctx_reg(state, CTX_SPSR_EL3, ep->spsr);
+
+	/*
+	 * Store the X0-X7 value from the entrypoint into the context
+	 * Use memcpy as we are in control of the layout of the structures
+	 */
+	gp_regs = get_gpregs_ctx(ctx);
+	memcpy(gp_regs, (void *)&ep->args, sizeof(aapcs64_params_t));
+}
+
+/*******************************************************************************
+ * Prepare the CPU system registers for first entry into secure or normal world
+ *
+ * If execution is requested to EL2 or hyp mode, SCTLR_EL2 is initialized
+ * If execution is requested to non-secure EL1 or svc mode, and the CPU supports
+ * EL2 then EL2 is disabled by configuring all necessary EL2 registers.
+ * For all entries, the EL1 registers are initialized from the cpu_context
+ ******************************************************************************/
+void cm_prepare_el3_exit(uint32_t security_state)
+{
+	uint32_t sctlr_elx, scr_el3, cptr_el2;
+	cpu_context_t *ctx = cm_get_context(security_state);
+
+	assert(ctx);
+
+	if (security_state == NON_SECURE) {
+		scr_el3 = read_ctx_reg(get_el3state_ctx(ctx), CTX_SCR_EL3);
+		if (scr_el3 & SCR_HCE_BIT) {
+			/* Use SCTLR_EL1.EE value to initialise sctlr_el2 */
+			sctlr_elx = read_ctx_reg(get_sysregs_ctx(ctx),
+						 CTX_SCTLR_EL1);
+			sctlr_elx &= ~SCTLR_EE_BIT;
+			sctlr_elx |= SCTLR_EL2_RES1;
+			write_sctlr_el2(sctlr_elx);
+		} else if (read_id_aa64pfr0_el1() &
+			   (ID_AA64PFR0_ELX_MASK << ID_AA64PFR0_EL2_SHIFT)) {
+			/* EL2 present but unused, need to disable safely */
+
+			/* HCR_EL2 = 0, except RW bit set to match SCR_EL3 */
+			write_hcr_el2((scr_el3 & SCR_RW_BIT) ? HCR_RW_BIT : 0);
+
+			/* SCTLR_EL2 : can be ignored when bypassing */
+
+			/* CPTR_EL2 : disable all traps TCPAC, TTA, TFP */
+			cptr_el2 = read_cptr_el2();
+			cptr_el2 &= ~(TCPAC_BIT | TTA_BIT | TFP_BIT);
+			write_cptr_el2(cptr_el2);
+
+			/* Enable EL1 access to timer */
+			write_cnthctl_el2(EL1PCEN_BIT | EL1PCTEN_BIT);
+
+			/* Set VPIDR, VMPIDR to match MIDR, MPIDR */
+			write_vpidr_el2(read_midr_el1());
+			write_vmpidr_el2(read_mpidr_el1());
+		}
+	}
+
+	el1_sysregs_context_restore(get_sysregs_ctx(ctx));
+
+	cm_set_next_context(ctx);
+}
+
 /*******************************************************************************
  * The next four functions are used by runtime services to save and restore EL3
  * and EL1 contexts on the 'cpu_context' structure for the specified security
@@ -132,13 +304,10 @@ void cm_el1_sysregs_context_restore(uint32_t security_state)
 }
 
 /*******************************************************************************
- * This function populates 'cpu_context' pertaining to the given security state
- * with the entrypoint, SPSR and SCR values so that an ERET from this security
- * state correctly restores corresponding values to drop the CPU to the next
- * exception level
+ * This function populates ELR_EL3 member of 'cpu_context' pertaining to the
+ * given security state with the given entrypoint
  ******************************************************************************/
-void cm_set_el3_eret_context(uint32_t security_state, uint64_t entrypoint,
-		uint32_t spsr, uint32_t scr)
+void cm_set_elr_el3(uint32_t security_state, uint64_t entrypoint)
 {
 	cpu_context_t *ctx;
 	el3_state_t *state;
@@ -146,23 +315,17 @@ void cm_set_el3_eret_context(uint32_t security_state, uint64_t entrypoint,
 	ctx = cm_get_context(security_state);
 	assert(ctx);
 
-	/* Program the interrupt routing model for this security state */
-	scr &= ~SCR_FIQ_BIT;
-	scr &= ~SCR_IRQ_BIT;
-	scr |= get_scr_el3_from_routing_model(security_state);
-
-	/* Populate EL3 state so that we've the right context before doing ERET */
+	/* Populate EL3 state so that ERET jumps to the correct entry */
 	state = get_el3state_ctx(ctx);
-	write_ctx_reg(state, CTX_SPSR_EL3, spsr);
 	write_ctx_reg(state, CTX_ELR_EL3, entrypoint);
-	write_ctx_reg(state, CTX_SCR_EL3, scr);
 }
 
 /*******************************************************************************
- * This function populates ELR_EL3 member of 'cpu_context' pertaining to the
- * given security state with the given entrypoint
+ * This function populates ELR_EL3 and SPSR_EL3 members of 'cpu_context'
+ * pertaining to the given security state
  ******************************************************************************/
-void cm_set_elr_el3(uint32_t security_state, uint64_t entrypoint)
+void cm_set_elr_spsr_el3(uint32_t security_state,
+			 uint64_t entrypoint, uint32_t spsr)
 {
 	cpu_context_t *ctx;
 	el3_state_t *state;
@@ -173,6 +336,7 @@ void cm_set_elr_el3(uint32_t security_state, uint64_t entrypoint)
 	/* Populate EL3 state so that ERET jumps to the correct entry */
 	state = get_el3state_ctx(ctx);
 	write_ctx_reg(state, CTX_ELR_EL3, entrypoint);
+	write_ctx_reg(state, CTX_SPSR_EL3, spsr);
 }
 
 /*******************************************************************************
@@ -233,26 +397,9 @@ uint32_t cm_get_scr_el3(uint32_t security_state)
 void cm_set_next_eret_context(uint32_t security_state)
 {
 	cpu_context_t *ctx;
-#if DEBUG
-	uint64_t sp_mode;
-#endif
 
 	ctx = cm_get_context(security_state);
 	assert(ctx);
 
-#if DEBUG
-	/*
-	 * Check that this function is called with SP_EL0 as the stack
-	 * pointer
-	 */
-	__asm__ volatile("mrs	%0, SPSel\n"
-			 : "=r" (sp_mode));
-
-	assert(sp_mode == MODE_SP_EL0);
-#endif
-
-	__asm__ volatile("msr	spsel, #1\n"
-			 "mov	sp, %0\n"
-			 "msr	spsel, #0\n"
-			 : : "r" (ctx));
+	cm_set_next_context(ctx);
 }

include/bl31/context_mgmt.h

@@ -34,6 +34,11 @@
 #include <cpu_data.h>
 #include <stdint.h>
 
+/*******************************************************************************
+ * Forward declarations
+ ******************************************************************************/
+struct entry_point_info;
+
 /*******************************************************************************
  * Function & variable prototypes
  ******************************************************************************/
@@ -45,12 +50,14 @@ void cm_set_context_by_mpidr(uint64_t mpidr,
 			     uint32_t security_state);
 static inline void cm_set_context(void *context, uint32_t security_state);
 void cm_el3_sysregs_context_save(uint32_t security_state);
+void cm_init_context(uint64_t mpidr, const struct entry_point_info *ep);
+void cm_prepare_el3_exit(uint32_t security_state);
 void cm_el3_sysregs_context_restore(uint32_t security_state);
 void cm_el1_sysregs_context_save(uint32_t security_state);
 void cm_el1_sysregs_context_restore(uint32_t security_state);
-void cm_set_el3_eret_context(uint32_t security_state, uint64_t entrypoint,
-			     uint32_t spsr, uint32_t scr);
 void cm_set_elr_el3(uint32_t security_state, uint64_t entrypoint);
+void cm_set_elr_spsr_el3(uint32_t security_state,
+			 uint64_t entrypoint, uint32_t spsr);
 void cm_write_scr_el3_bit(uint32_t security_state,
 			  uint32_t bit_pos,
 			  uint32_t value);

include/common/bl_common.h

@@ -33,7 +33,6 @@
 
 #define SECURE		0x0
 #define NON_SECURE	0x1
-#define PARAM_EP_SECURITY_MASK    0x1
 
 #define UP	1
 #define DOWN	0
@@ -64,10 +63,23 @@
 #define ENTRY_POINT_INFO_PC_OFFSET	0x08
 #define ENTRY_POINT_INFO_ARGS_OFFSET	0x18
 
+#define PARAM_EP_SECURITY_MASK    0x1
 #define GET_SECURITY_STATE(x) (x & PARAM_EP_SECURITY_MASK)
 #define SET_SECURITY_STATE(x, security) \
 			((x) = ((x) & ~PARAM_EP_SECURITY_MASK) | (security))
 
+#define EP_EE_MASK	0x2
+#define EP_EE_LITTLE	0x0
+#define EP_EE_BIG	0x2
+#define EP_GET_EE(x) (x & EP_EE_MASK)
+#define EP_SET_EE(x, ee) ((x) = ((x) & ~EP_EE_MASK) | (ee))
+
+#define EP_ST_MASK	0x4
+#define EP_ST_DISABLE	0x0
+#define EP_ST_ENABLE	0x4
+#define EP_GET_ST(x) (x & EP_ST_MASK)
+#define EP_SET_ST(x, ee) ((x) = ((x) & ~EP_ST_MASK) | (ee))
+
 #define PARAM_EP     0x01
 #define PARAM_IMAGE_BINARY  0x02
 #define PARAM_BL31       0x03

include/lib/aarch64/arch.h

@@ -167,6 +167,7 @@
 #define HCR_FMO_BIT		(1 << 3)
 
 /* CNTHCTL_EL2 definitions */
+#define EVNTEN_BIT		(1 << 2)
 #define EL1PCEN_BIT		(1 << 1)
 #define EL1PCTEN_BIT		(1 << 0)
 

include/lib/aarch64/arch_helpers.h

@@ -262,6 +262,9 @@ DEFINE_SYSREG_RW_FUNCS(cnthctl_el2)
 
 DEFINE_SYSREG_RW_FUNCS(tpidr_el3)
 
+DEFINE_SYSREG_RW_FUNCS(vpidr_el2)
+DEFINE_SYSREG_RW_FUNCS(vmpidr_el2)
+
 /* Implementation specific registers */
 
 DEFINE_RENAME_SYSREG_RW_FUNCS(cpuectlr_el1, CPUECTLR_EL1)

services/spd/tspd/tspd_common.c

@@ -45,9 +45,8 @@ int32_t tspd_init_secure_context(uint64_t entrypoint,
 				 uint64_t mpidr,
 				 tsp_context_t *tsp_ctx)
 {
-	uint32_t scr, sctlr;
-	el1_sys_regs_t *el1_state;
-	uint32_t spsr;
+	entry_point_info_t ep;
+	uint32_t ep_attr;
 
 	/* Passing a NULL context is a critical programming error */
 	assert(tsp_ctx);
@@ -58,51 +57,24 @@ int32_t tspd_init_secure_context(uint64_t entrypoint,
 	 */
 	assert(rw == TSP_AARCH64);
 
-	/*
-	 * This might look redundant if the context was statically
-	 * allocated but this function cannot make that assumption.
-	 */
-	memset(tsp_ctx, 0, sizeof(*tsp_ctx));
-
-	/*
-	 * Set the right security state, register width and enable access to
-	 * the secure physical timer for the SP.
-	 */
-	scr = read_scr();
-	scr &= ~SCR_NS_BIT;
-	scr &= ~SCR_RW_BIT;
-	scr |= SCR_ST_BIT;
-	if (rw == TSP_AARCH64)
-		scr |= SCR_RW_BIT;
-
-	/* Get a pointer to the S-EL1 context memory */
-	el1_state = get_sysregs_ctx(&tsp_ctx->cpu_ctx);
-
-	/*
-	 * Program the SCTLR_EL1 such that upon entry in S-EL1, caches and MMU are
-	 * disabled and exception endianess is set to be the same as EL3
-	 */
-	sctlr = read_sctlr_el3();
-	sctlr &= SCTLR_EE_BIT;
-	sctlr |= SCTLR_EL1_RES1;
-	write_ctx_reg(el1_state, CTX_SCTLR_EL1, sctlr);
-
-	/* Set this context as ready to be initialised i.e OFF */
+	/* Associate this context with the cpu specified */
+	tsp_ctx->mpidr = mpidr;
+	tsp_ctx->state = 0;
 	set_tsp_pstate(tsp_ctx->state, TSP_PSTATE_OFF);
-
-	/*
-	 * This context has not been used yet. It will become valid
-	 * when the TSP is interrupted and wants the TSPD to preserve
-	 * the context.
-	 */
 	clr_std_smc_active_flag(tsp_ctx->state);
 
-	/* Associate this context with the cpu specified */
-	tsp_ctx->mpidr = mpidr;
+	cm_set_context_by_mpidr(mpidr, &tsp_ctx->cpu_ctx, SECURE);
+
+	/* initialise an entrypoint to set up the CPU context */
+	ep_attr = SECURE | EP_ST_ENABLE;
+	if (read_sctlr_el3() & SCTLR_EE_BIT)
+		ep_attr |= EP_EE_BIG;
+	SET_PARAM_HEAD(&ep, PARAM_EP, VERSION_1, ep_attr);
+	ep.pc = entrypoint;
+	ep.spsr = SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
+	memset(&ep.args, 0, sizeof(ep.args));
 
-	cm_set_context(&tsp_ctx->cpu_ctx, SECURE);
-	spsr = SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
-	cm_set_el3_eret_context(SECURE, entrypoint, spsr, scr);
+	cm_init_context(mpidr, &ep);
 
 	return 0;
 }

services/spd/tspd/tspd_main.c

@@ -122,13 +122,9 @@ static uint64_t tspd_sel1_interrupt_handler(uint32_t id,
 						     CTX_ELR_EL3);
 	}
 
-	SMC_SET_EL3(&tsp_ctx->cpu_ctx,
-		    CTX_SPSR_EL3,
-		    SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS));
-	SMC_SET_EL3(&tsp_ctx->cpu_ctx,
-		    CTX_ELR_EL3,
-		    (uint64_t) &tsp_vectors->fiq_entry);
 	cm_el1_sysregs_context_restore(SECURE);
+	cm_set_elr_spsr_el3(SECURE, (uint64_t) &tsp_vectors->fiq_entry,
+		    SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS));
 	cm_set_next_eret_context(SECURE);
 
 	/*

services/std_svc/psci/psci_afflvl_off.c

@@ -42,8 +42,8 @@ typedef int (*afflvl_off_handler_t)(unsigned long, aff_map_node_t *);
  ******************************************************************************/
 static int psci_afflvl0_off(unsigned long mpidr, aff_map_node_t *cpu_node)
 {
-	unsigned int index, plat_state;
-	int rc = PSCI_E_SUCCESS;
+	unsigned int plat_state;
+	int rc;
 	unsigned long sctlr;
 
 	assert(cpu_node->level == MPIDR_AFFLVL0);
@@ -67,9 +67,6 @@ static int psci_afflvl0_off(unsigned long mpidr, aff_map_node_t *cpu_node)
 			return rc;
 	}
 
-	index = cpu_node->data;
-	memset(&psci_ns_entry_info[index], 0, sizeof(psci_ns_entry_info[index]));
-
 	/*
 	 * Arch. management. Perform the necessary steps to flush all
 	 * cpu caches.
@@ -96,6 +93,7 @@ static int psci_afflvl0_off(unsigned long mpidr, aff_map_node_t *cpu_node)
 	 * Plat. management: Perform platform specific actions to turn this
 	 * cpu off e.g. exit cpu coherency, program the power controller etc.
 	 */
+	rc = PSCI_E_SUCCESS;
 	if (psci_plat_pm_ops->affinst_off) {
 
 		/* Get the current physical state of this cpu */

services/std_svc/psci/psci_afflvl_on.c

@@ -75,8 +75,10 @@ static int psci_afflvl0_on(unsigned long target_cpu,
 			   unsigned long ns_entrypoint,
 			   unsigned long context_id)
 {
-	unsigned int index, plat_state;
+	unsigned int plat_state;
 	unsigned long psci_entrypoint;
+	uint32_t ns_scr_el3 = read_scr_el3();
+	uint32_t ns_sctlr_el1 = read_sctlr_el1();
 	int rc;
 
 	/* Sanity check to safeguard against data corruption */
@@ -103,8 +105,8 @@ static int psci_afflvl0_on(unsigned long target_cpu,
 	 * the non-secure world from the non-secure state from
 	 * where this call originated.
 	 */
-	index = cpu_node->data;
-	rc = psci_set_ns_entry_info(index, ns_entrypoint, context_id);
+	rc = psci_save_ns_entry(target_cpu, ns_entrypoint, context_id,
+				ns_scr_el3, ns_sctlr_el1);
 	if (rc != PSCI_E_SUCCESS)
 		return rc;
 
@@ -336,7 +338,7 @@ int psci_afflvl_on(unsigned long target_cpu,
 static unsigned int psci_afflvl0_on_finish(unsigned long mpidr,
 					   aff_map_node_t *cpu_node)
 {
-	unsigned int index, plat_state, state, rc = PSCI_E_SUCCESS;
+	unsigned int plat_state, state, rc;
 
 	assert(cpu_node->level == MPIDR_AFFLVL0);
 
@@ -383,11 +385,9 @@ static unsigned int psci_afflvl0_on_finish(unsigned long mpidr,
 	/*
 	 * Generic management: Now we just need to retrieve the
 	 * information that we had stashed away during the cpu_on
-	 * call to set this cpu on its way. First get the index
-	 * for restoring the re-entry info
+	 * call to set this cpu on its way.
 	 */
-	index = cpu_node->data;
-	psci_get_ns_entry_info(index);
+	cm_prepare_el3_exit(NON_SECURE);
 
 	/* State management: mark this cpu as on */
 	psci_set_state(cpu_node, PSCI_STATE_ON);
@@ -395,6 +395,7 @@ static unsigned int psci_afflvl0_on_finish(unsigned long mpidr,
 	/* Clean caches before re-entering normal world */
 	dcsw_op_louis(DCCSW);
 
+	rc = PSCI_E_SUCCESS;
 	return rc;
 }
 

services/std_svc/psci/psci_afflvl_suspend.c

@@ -132,10 +132,12 @@ static int psci_afflvl0_suspend(unsigned long mpidr,
 				unsigned long context_id,
 				unsigned int power_state)
 {
-	unsigned int index, plat_state;
+	unsigned int plat_state;
 	unsigned long psci_entrypoint, sctlr;
 	el3_state_t *saved_el3_state;
-	int rc = PSCI_E_SUCCESS;
+	uint32_t ns_scr_el3 = read_scr_el3();
+	uint32_t ns_sctlr_el1 = read_sctlr_el1();
+	int rc;
 
 	/* Sanity check to safeguard against data corruption */
 	assert(cpu_node->level == MPIDR_AFFLVL0);
@@ -163,8 +165,8 @@ static int psci_afflvl0_suspend(unsigned long mpidr,
 	 * Generic management: Store the re-entry information for the
 	 * non-secure world
 	 */
-	index = cpu_node->data;
-	rc = psci_set_ns_entry_info(index, ns_entrypoint, context_id);
+	rc = psci_save_ns_entry(read_mpidr_el1(), ns_entrypoint, context_id,
+				ns_scr_el3, ns_sctlr_el1);
 	if (rc != PSCI_E_SUCCESS)
 		return rc;
 
@@ -174,7 +176,6 @@ static int psci_afflvl0_suspend(unsigned long mpidr,
 	 * L1 caches and exit intra-cluster coherency et al
 	 */
 	cm_el3_sysregs_context_save(NON_SECURE);
-	rc = PSCI_E_SUCCESS;
 
 	/*
 	 * The EL3 state to PoC since it will be accessed after a
@@ -214,6 +215,8 @@ static int psci_afflvl0_suspend(unsigned long mpidr,
 	 * platform defined mailbox with the psci entrypoint,
 	 * program the power controller etc.
 	 */
+	rc = PSCI_E_SUCCESS;
+
 	if (psci_plat_pm_ops->affinst_suspend) {
 		plat_state = psci_get_phys_state(cpu_node);
 		rc = psci_plat_pm_ops->affinst_suspend(mpidr,
@@ -454,7 +457,7 @@ int psci_afflvl_suspend(unsigned long mpidr,
 static unsigned int psci_afflvl0_suspend_finish(unsigned long mpidr,
 						aff_map_node_t *cpu_node)
 {
-	unsigned int index, plat_state, state, rc = PSCI_E_SUCCESS;
+	unsigned int plat_state, state, rc;
 	int32_t suspend_level;
 
 	assert(cpu_node->level == MPIDR_AFFLVL0);
@@ -481,14 +484,11 @@ static unsigned int psci_afflvl0_suspend_finish(unsigned long mpidr,
 	}
 
 	/* Get the index for restoring the re-entry information */
-	index = cpu_node->data;
-
 	/*
 	 * Arch. management: Restore the stashed EL3 architectural
 	 * context from the 'cpu_context' structure for this cpu.
 	 */
 	cm_el3_sysregs_context_restore(NON_SECURE);
-	rc = PSCI_E_SUCCESS;
 
 	/*
 	 * Call the cpu suspend finish handler registered by the Secure Payload
@@ -509,7 +509,7 @@ static unsigned int psci_afflvl0_suspend_finish(unsigned long mpidr,
 	 * information that we had stashed away during the suspend
 	 * call to set this cpu on its way.
 	 */
-	psci_get_ns_entry_info(index);
+	cm_prepare_el3_exit(NON_SECURE);
 
 	/* State management: mark this cpu as on */
 	psci_set_state(cpu_node, PSCI_STATE_ON);
@@ -517,6 +517,7 @@ static unsigned int psci_afflvl0_suspend_finish(unsigned long mpidr,
 	/* Clean caches before re-entering normal world */
 	dcsw_op_louis(DCCSW);
 
+	rc = PSCI_E_SUCCESS;
 	return rc;
 }
 

services/std_svc/psci/psci_common.c

@@ -36,6 +36,7 @@
 #include <context_mgmt.h>
 #include <debug.h>
 #include <platform.h>
+#include <string.h>
 #include "psci_private.h"
 
 /*
@@ -50,7 +51,6 @@ const spd_pm_ops_t *psci_spd_pm;
  * array during startup.
  ******************************************************************************/
 suspend_context_t psci_suspend_context[PSCI_NUM_AFFS];
-ns_entry_info_t psci_ns_entry_info[PSCI_NUM_AFFS];
 
 /*******************************************************************************
  * Grand array that holds the platform's topology information for state
@@ -212,97 +212,36 @@ int psci_validate_mpidr(unsigned long mpidr, int level)
 }
 
 /*******************************************************************************
- * This function retrieves all the stashed information needed to correctly
- * resume a cpu's execution in the non-secure state after it has been physically
- * powered on i.e. turned ON or resumed from SUSPEND
+ * This function determines the full entrypoint information for the requested
+ * PSCI entrypoint on power on/resume and saves this in the non-secure CPU
+ * cpu_context, ready for when the core boots.
  ******************************************************************************/
-void psci_get_ns_entry_info(unsigned int index)
+int psci_save_ns_entry(uint64_t mpidr,
+		       uint64_t entrypoint, uint64_t context_id,
+		       uint32_t ns_scr_el3, uint32_t ns_sctlr_el1)
 {
-	unsigned long sctlr = 0, scr, el_status, id_aa64pfr0;
-	cpu_context_t *ns_entry_context;
-	gp_regs_t *ns_entry_gpregs;
+	uint32_t ep_attr, mode, sctlr, daif, ee;
+	entry_point_info_t ep;
 
-	scr = read_scr();
+	sctlr = ns_scr_el3 & SCR_HCE_BIT ? read_sctlr_el2() : ns_sctlr_el1;
+	ee = 0;
 
-	/* Find out which EL we are going to */
-	id_aa64pfr0 = read_id_aa64pfr0_el1();
-	el_status = (id_aa64pfr0 >> ID_AA64PFR0_EL2_SHIFT) &
-		ID_AA64PFR0_ELX_MASK;
-
-	/* Restore endianess */
-	if (psci_ns_entry_info[index].sctlr & SCTLR_EE_BIT)
-		sctlr |= SCTLR_EE_BIT;
-	else
-		sctlr &= ~SCTLR_EE_BIT;
-
-	/* Turn off MMU and Caching */
-	sctlr &= ~(SCTLR_M_BIT | SCTLR_C_BIT | SCTLR_M_BIT);
-
-	/* Set the register width */
-	if (psci_ns_entry_info[index].scr & SCR_RW_BIT)
-		scr |= SCR_RW_BIT;
-	else
-		scr &= ~SCR_RW_BIT;
-
-	scr |= SCR_NS_BIT;
-
-	if (el_status)
-		write_sctlr_el2(sctlr);
-	else
-		write_sctlr_el1(sctlr);
-
-	/* Fulfill the cpu_on entry reqs. as per the psci spec */
-	ns_entry_context = (cpu_context_t *) cm_get_context(NON_SECURE);
-	assert(ns_entry_context);
-
-	/*
-	 * Setup general purpose registers to return the context id and
-	 * prevent leakage of secure information into the normal world.
-	 */
-	ns_entry_gpregs = get_gpregs_ctx(ns_entry_context);
-	write_ctx_reg(ns_entry_gpregs,
-		      CTX_GPREG_X0,
-		      psci_ns_entry_info[index].context_id);
-
-	/*
-	 * Tell the context management library to setup EL3 system registers to
-	 * be able to ERET into the ns state, and SP_EL3 points to the right
-	 * context to exit from EL3 correctly.
-	 */
-	cm_set_el3_eret_context(NON_SECURE,
-			psci_ns_entry_info[index].eret_info.entrypoint,
-			psci_ns_entry_info[index].eret_info.spsr,
-			scr);
-
-	cm_set_next_eret_context(NON_SECURE);
-}
-
-/*******************************************************************************
- * This function retrieves and stashes all the information needed to correctly
- * resume a cpu's execution in the non-secure state after it has been physically
- * powered on i.e. turned ON or resumed from SUSPEND. This is done prior to
- * turning it on or before suspending it.
- ******************************************************************************/
-int psci_set_ns_entry_info(unsigned int index,
-			   unsigned long entrypoint,
-			   unsigned long context_id)
-{
-	int rc = PSCI_E_SUCCESS;
-	unsigned int rw, mode, ee, spsr = 0;
-	unsigned long id_aa64pfr0 = read_id_aa64pfr0_el1(), scr = read_scr();
-	unsigned long el_status;
-	unsigned long daif;
+	ep_attr = NON_SECURE | EP_ST_DISABLE;
+	if (sctlr & SCTLR_EE_BIT) {
+		ep_attr |= EP_EE_BIG;
+		ee = 1;
+	}
+	SET_PARAM_HEAD(&ep, PARAM_EP, VERSION_1, ep_attr);
 
-	/* Figure out what mode do we enter the non-secure world in */
-	el_status = (id_aa64pfr0 >> ID_AA64PFR0_EL2_SHIFT) &
-		ID_AA64PFR0_ELX_MASK;
+	ep.pc = entrypoint;
+	memset(&ep.args, 0, sizeof(ep.args));
+	ep.args.arg0 = context_id;
 
 	/*
 	 * Figure out whether the cpu enters the non-secure address space
 	 * in aarch32 or aarch64
 	 */
-	rw = scr & SCR_RW_BIT;
-	if (rw) {
+	if (ns_scr_el3 & SCR_RW_BIT) {
 
 		/*
 		 * Check whether a Thumb entry point has been provided for an
@@ -311,28 +250,12 @@ int psci_set_ns_entry_info(unsigned int index,
 		if (entrypoint & 0x1)
 			return PSCI_E_INVALID_PARAMS;
 
-		if (el_status && (scr & SCR_HCE_BIT)) {
-			mode = MODE_EL2;
-			ee = read_sctlr_el2() & SCTLR_EE_BIT;
-		} else {
-			mode = MODE_EL1;
-			ee = read_sctlr_el1() & SCTLR_EE_BIT;
-		}
-
-		spsr = SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
+		mode = ns_scr_el3 & SCR_HCE_BIT ? MODE_EL2 : MODE_EL1;
 
-		psci_ns_entry_info[index].sctlr |= ee;
-		psci_ns_entry_info[index].scr |= SCR_RW_BIT;
+		ep.spsr = SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
 	} else {
 
-
-		if (el_status && (scr & SCR_HCE_BIT)) {
-			mode = MODE32_hyp;
-			ee = read_sctlr_el2() & SCTLR_EE_BIT;
-		} else {
-			mode = MODE32_svc;
-			ee = read_sctlr_el1() & SCTLR_EE_BIT;
-		}
+		mode = ns_scr_el3 & SCR_HCE_BIT ? MODE32_hyp : MODE32_svc;
 
 		/*
 		 * TODO: Choose async. exception bits if HYP mode is not
@@ -340,18 +263,13 @@ int psci_set_ns_entry_info(unsigned int index,
 		 */
 		daif = DAIF_ABT_BIT | DAIF_IRQ_BIT | DAIF_FIQ_BIT;
 
-		spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, daif);
-
-		/* Ensure that the CSPR.E and SCTLR.EE bits match */
-		psci_ns_entry_info[index].sctlr |= ee;
-		psci_ns_entry_info[index].scr &= ~SCR_RW_BIT;
+		ep.spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, daif);
 	}
 
-	psci_ns_entry_info[index].eret_info.entrypoint = entrypoint;
-	psci_ns_entry_info[index].eret_info.spsr = spsr;
-	psci_ns_entry_info[index].context_id = context_id;
+	/* initialise an entrypoint to set up the CPU context */
+	cm_init_context(mpidr, &ep);
 
-	return rc;
+	return PSCI_E_SUCCESS;
 }
 
 /*******************************************************************************

services/std_svc/psci/psci_private.h

@@ -35,22 +35,6 @@
 #include <bakery_lock.h>
 #include <psci.h>
 
-/*******************************************************************************
- * The following two data structures hold the generic information to bringup
- * a suspended/hotplugged out cpu
- ******************************************************************************/
-typedef struct eret_params {
-	unsigned long entrypoint;
-	unsigned long spsr;
-} eret_params_t;
-
-typedef struct ns_entry_info {
-	eret_params_t eret_info;
-	unsigned long context_id;
-	unsigned int scr;
-	unsigned int sctlr;
-} ns_entry_info_t;
-
 /*******************************************************************************
  * The following two data structures hold the topology tree which in turn tracks
  * the state of the all the affinity instances supported by the platform.
@@ -85,7 +69,6 @@ typedef unsigned int (*afflvl_power_on_finisher_t)(unsigned long,
  * Data prototypes
  ******************************************************************************/
 extern suspend_context_t psci_suspend_context[PSCI_NUM_AFFS];
-extern ns_entry_info_t psci_ns_entry_info[PSCI_NUM_AFFS];
 extern const plat_pm_ops_t *psci_plat_pm_ops;
 extern aff_map_node_t psci_aff_map[PSCI_NUM_AFFS];
 
@@ -102,7 +85,6 @@ int get_max_afflvl(void);
 unsigned short psci_get_state(aff_map_node_t *node);
 unsigned short psci_get_phys_state(aff_map_node_t *node);
 void psci_set_state(aff_map_node_t *node, unsigned short state);
-void psci_get_ns_entry_info(unsigned int index);
 unsigned long mpidr_set_aff_inst(unsigned long, unsigned char, int);
 int psci_validate_mpidr(unsigned long, int);
 int get_power_on_target_afflvl(unsigned long mpidr);
@@ -110,9 +92,9 @@ void psci_afflvl_power_on_finish(unsigned long,
 				int,
 				int,
 				afflvl_power_on_finisher_t *);
-int psci_set_ns_entry_info(unsigned int index,
-				unsigned long entrypoint,
-				unsigned long context_id);
+int psci_save_ns_entry(uint64_t mpidr,
+		       uint64_t entrypoint, uint64_t context_id,
+		       uint32_t caller_scr_el3, uint32_t caller_sctlr_el1);
 int psci_check_afflvl_range(int start_afflvl, int end_afflvl);
 void psci_acquire_afflvl_locks(unsigned long mpidr,
 				int start_afflvl,

services/std_svc/psci/psci_setup.c

@@ -59,7 +59,7 @@ static aff_limits_node_t psci_aff_limits[MPIDR_MAX_AFFLVL + 1];
 
 /*******************************************************************************
  * 'psci_ns_einfo_idx' keeps track of the next free index in the
- * 'psci_ns_entry_info' & 'psci_suspend_context' arrays.
+ * 'psci_suspend_context' arrays.
  ******************************************************************************/
 static unsigned int psci_ns_einfo_idx;