diff options
| -rw-r--r-- | plat/arm/css/common/aarch64/css_helpers.S | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/plat/arm/css/common/aarch64/css_helpers.S b/plat/arm/css/common/aarch64/css_helpers.S index d1702708..27476186 100644 --- a/plat/arm/css/common/aarch64/css_helpers.S +++ b/plat/arm/css/common/aarch64/css_helpers.S @@ -37,19 +37,36 @@ .globl css_calc_core_pos_swap_cluster .weak plat_is_my_cpu_primary - /* ----------------------------------------------------- - * void plat_secondary_cold_boot_setup (void); + /* --------------------------------------------------------------------- + * void plat_secondary_cold_boot_setup(void); * - * This function performs any platform specific actions - * needed for a secondary cpu after a cold reset e.g - * mark the cpu's presence, mechanism to place it in a - * holding pen etc. - * ----------------------------------------------------- + * 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 - /* todo: Implement secondary CPU cold boot setup on CSS platforms */ +#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 /* --------------------------------------------------------------------- |