Hi Catalin,
On 2014年01月24日 01:50, Catalin Marinas wrote:
On Fri, Jan 17, 2014 at 12:25:05PM +0000, Hanjun Guo wrote:
--- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -48,6 +48,7 @@ #include <asm/sections.h> #include <asm/tlbflush.h> #include <asm/ptrace.h> +#include <asm/acpi.h> /*
- as from 2.5, kernels no longer have an init_tasks structure
@@ -280,7 +281,7 @@ static void (*smp_cross_call)(const struct cpumask *, unsigned int);
- cpu logical map array containing MPIDR values related to logical
- cpus. Assumes that cpu_logical_map(0) has already been initialized.
*/ -void __init smp_init_cpus(void) +static int __init of_smp_init_cpus(void) { struct device_node *dn = NULL; unsigned int i, cpu = 1; @@ -364,6 +365,10 @@ next: cpu++; }
- /* No device tree or no CPU node in DT */
- if (cpu == 1 && !bootcpu_valid)
return -ENODEV;
- /* sanity check */ if (cpu > NR_CPUS) pr_warning("no. of cores (%d) greater than configured maximum of %d - clipping\n",
@@ -371,7 +376,7 @@ next: if (!bootcpu_valid) { pr_err("DT missing boot CPU MPIDR, not enabling secondaries\n");
return;
}return -EINVAL;
/* @@ -381,6 +386,39 @@ next: for (i = 0; i < NR_CPUS; i++) if (cpu_logical_map(i) != INVALID_HWID) set_cpu_possible(i, true);
- return 0;
+}
+/*
- In ACPI mode, the cpu possible map was enumerated before SMP
- initialization when MADT table was parsed, so we can get the
- possible map here to initialize CPUs.
- */
+static void __init acpi_smp_init_cpus(void) +{
- int cpu;
- const char *enable_method;
- for_each_possible_cpu(cpu) {
enable_method = acpi_get_enable_method(cpu);
if (!enable_method)
continue;
cpu_ops[cpu] = cpu_get_ops(enable_method);
if (!cpu_ops[cpu])
continue;
cpu_ops[cpu]->cpu_init(NULL, cpu);
- }
+}
+void __init smp_init_cpus(void) +{
- if (!of_smp_init_cpus())
return;
- acpi_smp_init_cpus(); }
With DT we initialise the cpu_ops[0] via cpu_read_bootcpu_ops() called from setup_arch(). This is needed because with PSCI we use cpu_ops for power management even if it's a UP system. Do you get a some kernel warning about device node for the boot cpu not found?
Thanks for pointing this out, actually we didn't find a dts file with spin-table method for SMP initialization, and this patch is not fully tested (only spin-table method is supported in ACPI now), we are working on that and get this patch fully tested.
I will review the code carefully in your comments, and update the code accordingly.
--- a/drivers/acpi/plat/arm-core.c +++ b/drivers/acpi/plat/arm-core.c @@ -367,6 +367,32 @@ static void __init acpi_process_madt(void) } /*
- To see PCSI is enabled or not.
- PSCI is not available for ACPI 5.0, return FALSE for now.
- FIXME: should we introduce early_param("psci", func) for test purpose?
- */
+static bool acpi_psci_smp_available(int cpu) +{
- return FALSE;
+}
+static const char *enable_method[] = {
- "psci",
- "spin-table",
- NULL
+};
+const char *acpi_get_enable_method(int cpu) +{
- if (acpi_psci_smp_available(cpu))
return enable_method[0];
- else
return enable_method[1];
+}
You could just use literal strings here, actually even ignoring PSCI until available.
Ok.
Thanks Hanjun