From: Yinghai Lu <ying...@kernel.org> We need to parse APIC ID for IOAPIC registration for IOAPIC hotplug. ACPI _MAT method and MADT table are used to figure out IOAPIC ID, just like parsing CPU APIC ID for CPU hotplug.
[ tglx: Fixed docbook comment ] Signed-off-by: Yinghai Lu <ying...@kernel.org> Signed-off-by: Jiang Liu <jiang....@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> Cc: Tony Luck <tony.l...@intel.com> Cc: Joerg Roedel <j...@8bytes.org> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> Cc: Rafael J. Wysocki <r...@rjwysocki.net> Cc: Bjorn Helgaas <bhelg...@google.com> Cc: Randy Dunlap <rdun...@infradead.org> Cc: Borislav Petkov <b...@alien8.de> Cc: Len Brown <l...@kernel.org> Link: http://lkml.kernel.org/r/1414387308-27148-8-git-send-email-jiang....@linux.intel.com Signed-off-by: Thomas Gleixner <t...@linutronix.de> --- drivers/acpi/processor_core.c | 123 ++++++++++++++++++++++++++++++++++++++--- include/linux/acpi.h | 4 ++ 2 files changed, 118 insertions(+), 9 deletions(-) diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index 02e48394276c..7962651cdbd4 100644 --- a/drivers/acpi/processor_core.c +++ b/drivers/acpi/processor_core.c @@ -4,6 +4,10 @@ * * Alex Chiang <achi...@hp.com> * - Unified x86/ia64 implementations + * + * I/O APIC hotplug support + * Yinghai Lu <ying...@kernel.org> + * Jiang Liu <jiang....@intel.com> */ #include <linux/export.h> #include <linux/acpi.h> @@ -12,6 +16,21 @@ #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("processor_core"); +static struct acpi_table_madt *get_madt_table(void) +{ + static struct acpi_table_madt *madt; + static int read_madt; + + if (!read_madt) { + if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0, + (struct acpi_table_header **)&madt))) + madt = NULL; + read_madt++; + } + + return madt; +} + static int map_lapic_id(struct acpi_subtable_header *entry, u32 acpi_id, int *apic_id) { @@ -67,17 +86,10 @@ static int map_lsapic_id(struct acpi_subtable_header *entry, static int map_madt_entry(int type, u32 acpi_id) { unsigned long madt_end, entry; - static struct acpi_table_madt *madt; - static int read_madt; int phys_id = -1; /* CPU hardware ID */ + struct acpi_table_madt *madt; - if (!read_madt) { - if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0, - (struct acpi_table_header **)&madt))) - madt = NULL; - read_madt++; - } - + madt = get_madt_table(); if (!madt) return phys_id; @@ -203,3 +215,96 @@ int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id) return acpi_map_cpuid(phys_id, acpi_id); } EXPORT_SYMBOL_GPL(acpi_get_cpuid); + +#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC +static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base, + u64 *phys_addr, int *ioapic_id) +{ + struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry; + + if (ioapic->global_irq_base != gsi_base) + return 0; + + *phys_addr = ioapic->address; + *ioapic_id = ioapic->id; + return 1; +} + +static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr) +{ + struct acpi_subtable_header *hdr; + unsigned long madt_end, entry; + struct acpi_table_madt *madt; + int apic_id = -1; + + madt = get_madt_table(); + if (!madt) + return apic_id; + + entry = (unsigned long)madt; + madt_end = entry + madt->header.length; + + /* Parse all entries looking for a match. */ + entry += sizeof(struct acpi_table_madt); + while (entry + sizeof(struct acpi_subtable_header) < madt_end) { + hdr = (struct acpi_subtable_header *)entry; + if (hdr->type == ACPI_MADT_TYPE_IO_APIC && + get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id)) + break; + else + entry += hdr->length; + } + + return apic_id; +} + +static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base, + u64 *phys_addr) +{ + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + struct acpi_subtable_header *header; + union acpi_object *obj; + int apic_id = -1; + + if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer))) + goto exit; + + if (!buffer.length || !buffer.pointer) + goto exit; + + obj = buffer.pointer; + if (obj->type != ACPI_TYPE_BUFFER || + obj->buffer.length < sizeof(struct acpi_subtable_header)) + goto exit; + + header = (struct acpi_subtable_header *)obj->buffer.pointer; + if (header->type == ACPI_MADT_TYPE_IO_APIC) + get_ioapic_id(header, gsi_base, phys_addr, &apic_id); + +exit: + kfree(buffer.pointer); + return apic_id; +} + +/** + * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base + * @handle: ACPI object for IOAPIC device + * @gsi_base: GSI base to match with + * @phys_addr: Pointer to store physical address of matching IOAPIC record + * + * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search + * for an ACPI IOAPIC record matching @gsi_base. + * Return IOAPIC id and store physical address in @phys_addr if found a match, + * otherwise return <0. + */ +int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr) +{ + int apic_id; + + apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr); + if (apic_id == -1) + apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr); + + return apic_id; +} +#endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */ diff --git a/include/linux/acpi.h b/include/linux/acpi.h index e53822148b6a..24c7aa8b1d20 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -152,6 +152,10 @@ int acpi_map_cpu(acpi_handle handle, int physid, int *pcpu); int acpi_unmap_cpu(int cpu); #endif /* CONFIG_ACPI_HOTPLUG_CPU */ +#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC +int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr); +#endif + int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base); int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base); int acpi_ioapic_registered(acpi_handle handle, u32 gsi_base); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
