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-rw-r--r--plat/arm/css/common/aarch64/css_helpers.S120
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+/*
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <cpu_macros.S>
+#include <platform_def.h>
+
+ .weak plat_secondary_cold_boot_setup
+ .weak plat_get_my_entrypoint
+ .globl css_calc_core_pos_swap_cluster
+ .weak plat_is_my_cpu_primary
+
+ /* ---------------------------------------------------------------------
+ * void plat_secondary_cold_boot_setup(void);
+ *
+ * In the normal boot flow, cold-booting secondary CPUs is not yet
+ * implemented and they panic.
+ *
+ * When booting an EL3 payload, secondary CPUs are placed in a holding
+ * pen, waiting for their mailbox to be populated. Note that all CPUs
+ * share the same mailbox ; therefore, populating it will release all
+ * CPUs from their holding pen. If finer-grained control is needed then
+ * this should be handled in the code that secondary CPUs jump to.
+ * ---------------------------------------------------------------------
+ */
+func plat_secondary_cold_boot_setup
+#ifndef EL3_PAYLOAD_BASE
+ /* TODO: Implement secondary CPU cold boot setup on CSS platforms */
+cb_panic:
+ b cb_panic
+#else
+ mov_imm x0, PLAT_ARM_TRUSTED_MAILBOX_BASE
+
+ /* Wait until the mailbox gets populated */
+poll_mailbox:
+ ldr x1, [x0]
+ cbz x1, 1f
+ br x1
+1:
+ wfe
+ b poll_mailbox
+#endif /* EL3_PAYLOAD_BASE */
+endfunc plat_secondary_cold_boot_setup
+
+ /* ---------------------------------------------------------------------
+ * uintptr_t plat_get_my_entrypoint (void);
+ *
+ * Main job of this routine is to distinguish between a cold and a warm
+ * boot. On CSS platforms, this distinction is based on the contents of
+ * the Trusted Mailbox. It is initialised to zero by the SCP before the
+ * AP cores are released from reset. Therefore, a zero mailbox means
+ * it's a cold reset.
+ *
+ * This functions returns the contents of the mailbox, i.e.:
+ * - 0 for a cold boot;
+ * - the warm boot entrypoint for a warm boot.
+ * ---------------------------------------------------------------------
+ */
+func plat_get_my_entrypoint
+ mov_imm x0, PLAT_ARM_TRUSTED_MAILBOX_BASE
+ ldr x0, [x0]
+ ret
+endfunc plat_get_my_entrypoint
+
+ /* -----------------------------------------------------------
+ * unsigned int css_calc_core_pos_swap_cluster(u_register_t mpidr)
+ * Utility function to calculate the core position by
+ * swapping the cluster order. This is necessary in order to
+ * match the format of the boot information passed by the SCP
+ * and read in plat_is_my_cpu_primary below.
+ * -----------------------------------------------------------
+ */
+func css_calc_core_pos_swap_cluster
+ and x1, x0, #MPIDR_CPU_MASK
+ and x0, x0, #MPIDR_CLUSTER_MASK
+ eor x0, x0, #(1 << MPIDR_AFFINITY_BITS) // swap cluster order
+ add x0, x1, x0, LSR #6
+ ret
+endfunc css_calc_core_pos_swap_cluster
+
+ /* -----------------------------------------------------
+ * unsigned int plat_is_my_cpu_primary (void);
+ *
+ * Find out whether the current cpu is the primary
+ * cpu (applicable ony after a cold boot)
+ * -----------------------------------------------------
+ */
+#if CSS_USE_SCMI_SDS_DRIVER
+func plat_is_my_cpu_primary
+ mov x9, x30
+ bl plat_my_core_pos
+ mov x4, x0
+ bl sds_get_primary_cpu_id
+ /* Check for error */
+ mov x1, #0xffffffff
+ cmp x0, x1
+ b.eq 1f
+ cmp x0, x4
+ cset w0, eq
+ ret x9
+1:
+ no_ret plat_panic_handler
+endfunc plat_is_my_cpu_primary
+#else
+func plat_is_my_cpu_primary
+ mov x9, x30
+ bl plat_my_core_pos
+ mov_imm x1, SCP_BOOT_CFG_ADDR
+ ldr x1, [x1]
+ ubfx x1, x1, #PLAT_CSS_PRIMARY_CPU_SHIFT, \
+ #PLAT_CSS_PRIMARY_CPU_BIT_WIDTH
+ cmp x0, x1
+ cset w0, eq
+ ret x9
+endfunc plat_is_my_cpu_primary
+#endif