Patrick Georgi (patrick@georgi-clan.de) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/6311
-gerrit
commit c9abb1df5bc6082cef59a0d116df13622f6cba92 Author: Patrick Georgi patrick@georgi-clan.de Date: Mon Jul 21 20:58:18 2014 +0200
x86/smm: Initialize SMM on CPUs one-by-one
We currently race in SMM init on Atom 230 (and potentially other CPUs). At least on the 230, this leads to a hang on RSM, likely because both hyperthreads mess around with SMBASE and other SMM state variables in parallel without coordination.
Change it so first APs are spun up and sent to sleep, then BSP initializes SMM, then every CPU, one after another.
Change-Id: I1ae864e37546298ea222e81349c27cf774ed251f Signed-off-by: Patrick Georgi patrick@georgi-clan.de --- src/cpu/x86/lapic/lapic_cpu_init.c | 46 ++++++++++++++++++++++++++++++++++---- 1 file changed, 42 insertions(+), 4 deletions(-)
diff --git a/src/cpu/x86/lapic/lapic_cpu_init.c b/src/cpu/x86/lapic/lapic_cpu_init.c index 09b6b9e..35863a1 100644 --- a/src/cpu/x86/lapic/lapic_cpu_init.c +++ b/src/cpu/x86/lapic/lapic_cpu_init.c @@ -463,6 +463,39 @@ static void start_other_cpus(struct bus *cpu_bus, device_t bsp_cpu)
}
+static void smm_other_cpus(struct bus *cpu_bus, device_t bsp_cpu) +{ + device_t cpu; + int pre_count = atomic_read(&active_cpus); + + /* Loop through the cpus once to let them run through SMM relocator */ + + for(cpu = cpu_bus->children; cpu ; cpu = cpu->sibling) { + if (cpu->path.type != DEVICE_PATH_APIC) { + continue; + } + + printk(BIOS_ERR, "considering CPU 0x%02x for SMM init\n", + cpu->path.apic.apic_id); + + if (cpu==bsp_cpu) + continue; + + if (!cpu->enabled) { + continue; + } + + if (!start_cpu(cpu)) { + /* Record the error in cpu? */ + printk(BIOS_ERR, "CPU 0x%02x would not start!\n", + cpu->path.apic.apic_id); + } + + /* FIXME: endless loop */ + while (atomic_read(&active_cpus) != pre_count) ; + } +} + static void wait_other_cpus_stop(struct bus *cpu_bus) { device_t cpu; @@ -531,10 +564,6 @@ void initialize_cpus(struct bus *cpu_bus) copy_secondary_start_to_lowest_1M(); #endif
-#if CONFIG_HAVE_SMI_HANDLER - smm_init(); -#endif - #if CONFIG_SMP && CONFIG_MAX_CPUS > 1 /* start all aps at first, so we can init ECC all together */ if (IS_ENABLED(CONFIG_PARALLEL_CPU_INIT)) @@ -551,4 +580,13 @@ void initialize_cpus(struct bus *cpu_bus) /* Now wait the rest of the cpus stop*/ wait_other_cpus_stop(cpu_bus); #endif + +#if CONFIG_HAVE_SMI_HANDLER + /* BSP only, all APs are sleeping */ + smm_init(); +#if CONFIG_SMP && CONFIG_MAX_CPUS > 1 + last_cpu_index = 0; + smm_other_cpus(cpu_bus, info->cpu); +#endif +#endif }