On 2014-8-18 22:27, Catalin Marinas wrote:

On Mon, Aug 04, 2014 at 04:28:16PM +0100, Hanjun Guo wrote:

quoted

diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
index 022f4ad..a81898d 100644
--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h

@@ -12,6 +12,8 @@
 #ifndef _ASM_ACPI_H
 #define _ASM_ACPI_H
 
+#include <asm/smp_plat.h>
+
 /* Basic configuration for ACPI */
 #ifdef	CONFIG_ACPI
 /*

@@ -59,6 +61,18 @@ static inline void disable_acpi(void)
 	acpi_noirq = 1;
 }
 
+u32 pack_mpidr_into_32_bits(u64 mpidr);

I would define this as a static inline function here.

ok, will update it.

quoted

diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index e32321c..4007313 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c

@@ -64,6 +64,38 @@ static int map_lsapic_id(struct acpi_subtable_header *entry,
 	return 0;
 }
 
+/*
+ * On ARM platform, MPIDR value is the hardware ID as apic ID
+ * on Intel platforms
+ */
+static int map_gicc_mpidr(struct acpi_subtable_header *entry,
+		int device_declaration, u32 acpi_id, int *mpidr)
+{
+	struct acpi_madt_generic_interrupt *gicc =
+	    container_of(entry, struct acpi_madt_generic_interrupt, header);
+
+	if (!(gicc->flags & ACPI_MADT_ENABLED))
+		return -ENODEV;
+
+	/* In the GIC interrupt model, logical processors are
+	 * required to have a Processor Device object in the DSDT,
+	 * so we should check device_declaration here
+	 */
+	if (device_declaration && (gicc->uid == acpi_id)) {
+		/*
+		 * Only bits [0:7] Aff0, bits [8:15] Aff1, bits [16:23] Aff2
+		 * and bits [32:39] Aff3 are meaningful, so pack the Affx
+		 * fields into a single 32 bit identifier to accommodate the
+		 * acpi processor drivers.
+		 */
+		*mpidr = ((gicc->arm_mpidr & 0xff00000000) >> 8)
+			 | gicc->arm_mpidr;

You can use pack_mpidr_into_32_bits().

processor_core.c will be used by x86 and ia64 too, it will cause
compile error on !ARM64 platforms.

Thanks
Hanjun