From d4a29ed6db32ae2f21561e87e27936782e0b8a44 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 27 Jan 2022 15:46:36 +0000 Subject: hw/arm/boot: Don't write secondary boot stub if using PSCI MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If we're using PSCI emulation to start secondary CPUs, there is no point in writing the "secondary boot" stub code, because it will never be used -- secondary CPUs start powered-off, and when powered on are set to begin execution at the address specified by the guest's power-on PSCI call, not at the stub. Move the call to the hook that writes the secondary boot stub code so that we can do it only if we're starting a Linux kernel and not using PSCI. (None of the users of the hook care about the ordering of its call relative to anything else: they only use it to write a rom blob to guest memory.) Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Reviewed-by: Niek Linnenbank Tested-by: Cédric Le Goater Tested-by: Niek Linnenbank Message-id: 20220127154639.2090164-14-peter.maydell@linaro.org --- hw/arm/boot.c | 35 ++++++++++++++++++++++++----------- 1 file changed, 24 insertions(+), 11 deletions(-) (limited to 'hw/arm') diff --git a/hw/arm/boot.c b/hw/arm/boot.c index 0424c17..184628c 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -804,7 +804,7 @@ static void do_cpu_reset(void *opaque) set_kernel_args(info, as); } } - } else { + } else if (info->secondary_cpu_reset_hook) { info->secondary_cpu_reset_hook(cpu, info); } } @@ -1030,13 +1030,6 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, elf_machine = EM_ARM; } - if (!info->secondary_cpu_reset_hook) { - info->secondary_cpu_reset_hook = default_reset_secondary; - } - if (!info->write_secondary_boot) { - info->write_secondary_boot = default_write_secondary; - } - if (info->nb_cpus == 0) info->nb_cpus = 1; @@ -1216,9 +1209,6 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, write_bootloader("bootloader", info->loader_start, primary_loader, fixupcontext, as); - if (info->nb_cpus > 1) { - info->write_secondary_boot(cpu, info); - } if (info->write_board_setup) { info->write_board_setup(cpu, info); } @@ -1385,6 +1375,29 @@ void arm_load_kernel(ARMCPU *cpu, MachineState *ms, struct arm_boot_info *info) } } + if (info->psci_conduit == QEMU_PSCI_CONDUIT_DISABLED && + info->is_linux && info->nb_cpus > 1) { + /* + * We're booting Linux but not using PSCI, so for SMP we need + * to write a custom secondary CPU boot loader stub, and arrange + * for the secondary CPU reset to make the accompanying initialization. + */ + if (!info->secondary_cpu_reset_hook) { + info->secondary_cpu_reset_hook = default_reset_secondary; + } + if (!info->write_secondary_boot) { + info->write_secondary_boot = default_write_secondary; + } + info->write_secondary_boot(cpu, info); + } else { + /* + * No secondary boot stub; don't use the reset hook that would + * have set the CPU up to call it + */ + info->write_secondary_boot = NULL; + info->secondary_cpu_reset_hook = NULL; + } + /* * arm_load_dtb() may add a PSCI node so it must be called after we have * decided whether to enable PSCI and set the psci-conduit CPU properties. -- cgit v1.1