| Message ID | 1421247905-3749-12-git-send-email-hanjun.guo@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 01/14/2015 09:04 AM, Hanjun Guo wrote: > Introduce a new function map_gicc_mpidr() to allow MPIDRs to be obtained > from the GICC Structure introduced by ACPI 5.1. > > MPIDR is the CPU hardware ID as local APIC ID on x86 platform, so we use > MPIDR not the GIC CPU interface ID to identify CPUs. > > Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> > Tested-by: Yijing Wang <wangyijing@huawei.com> > Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> > --- Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
On Wed, Jan 14, 2015 at 03:04:59PM +0000, Hanjun Guo wrote: > --- 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; Nitpick: I would clarify the comment here since "meaningful" doesn't necessarily mean that the other bits are 0. And if they are not, the above masking is not enough. Looking at the ACPI 5.1 spec, bits other than Aff[0-3] must be zero. Same for the pack_mpidr() comment.
On 2015?01?20? 19:17, Catalin Marinas wrote: > On Wed, Jan 14, 2015 at 03:04:59PM +0000, Hanjun Guo wrote: >> --- 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; > > Nitpick: I would clarify the comment here since "meaningful" doesn't > necessarily mean that the other bits are 0. And if they are not, the > above masking is not enough. Looking at the ACPI 5.1 spec, bits other > than Aff[0-3] must be zero. > > Same for the pack_mpidr() comment. OK, how about: /* * bits other than [0:7] Aff0, [8:15] Aff1, [16:23] Aff2 and * [32:39] Aff3 must be 0 which is defined in ACPI 5.1, so pack * the Affx fields into a single 32 bit identifier to accommodate * the acpi processor drivers. */ Thanks Hanjun
On Wed, Jan 14, 2015 at 03:04:59PM +0000, Hanjun Guo wrote: > Introduce a new function map_gicc_mpidr() to allow MPIDRs to be obtained > from the GICC Structure introduced by ACPI 5.1. > > MPIDR is the CPU hardware ID as local APIC ID on x86 platform, so we use > MPIDR not the GIC CPU interface ID to identify CPUs. > > Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> > Tested-by: Yijing Wang <wangyijing@huawei.com> > Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> > --- > arch/arm64/include/asm/acpi.h | 29 +++++++++++++++++++++++++++++ > arch/arm64/kernel/acpi.c | 1 - > drivers/acpi/processor_core.c | 37 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 66 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > index c82d4a1..639bb2a 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 > #define acpi_strict 1 /* No out-of-spec workarounds on ARM64 */ > @@ -45,6 +47,33 @@ static inline void enable_acpi(void) > acpi_noirq = 0; > } > > +/* MPIDR value provided in GICC structure is 64 bits, but the > + * existing apic_id (CPU hardware ID) using in acpi processor > + * driver is 32-bit, to conform to the same datatype we need > + * to repack the GICC structure MPIDR. > + * > + * Only 32 bits of MPIDR are used: > + * > + * Bits [0:7] Aff0; > + * Bits [8:15] Aff1; > + * Bits [16:23] Aff2; > + * Bits [32:39] Aff3; > + */ > +static inline u32 pack_mpidr(u64 mpidr) > +{ > + return (u32) ((mpidr & 0xff00000000) >> 8) | mpidr; > +} > + > +/* > + * The ACPI processor driver for ACPI core code needs this macro > + * to find out this cpu was already mapped (mapping from CPU hardware > + * ID to CPU logical ID) or not. > + * > + * cpu_logical_map(cpu) is the mapping of MPIDR and the logical cpu, > + * and MPIDR is the cpu hardware ID we needed to pack. > + */ > +#define cpu_physical_id(cpu) pack_mpidr(cpu_logical_map(cpu)) Do we need this mpidr packing only because in drivers/acpi/processor_core.c phys_id is defined as an int ? What you could do, is to typedef a cpuid_t type in arch code (with appropriate size and a corresponding invalid value, say ~0) and use that instead of an int in drivers/acpi/processor_core.c to store phys_id. phys_id is used as an error value too (ie -1 as a magic number), see drivers/acpi/acpi_processor.c, retrieved through acpi_get_phys_id(), it should not be that difficult to change the parsing API to keep current code behaviour unchanged and define at the same time a proper type for the cpu physical identifier, with no mpidr packing needed whatsoever. Thanks, Lorenzo
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index c82d4a1..639bb2a 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 #define acpi_strict 1 /* No out-of-spec workarounds on ARM64 */ @@ -45,6 +47,33 @@ static inline void enable_acpi(void) acpi_noirq = 0; } +/* MPIDR value provided in GICC structure is 64 bits, but the + * existing apic_id (CPU hardware ID) using in acpi processor + * driver is 32-bit, to conform to the same datatype we need + * to repack the GICC structure MPIDR. + * + * Only 32 bits of MPIDR are used: + * + * Bits [0:7] Aff0; + * Bits [8:15] Aff1; + * Bits [16:23] Aff2; + * Bits [32:39] Aff3; + */ +static inline u32 pack_mpidr(u64 mpidr) +{ + return (u32) ((mpidr & 0xff00000000) >> 8) | mpidr; +} + +/* + * The ACPI processor driver for ACPI core code needs this macro + * to find out this cpu was already mapped (mapping from CPU hardware + * ID to CPU logical ID) or not. + * + * cpu_logical_map(cpu) is the mapping of MPIDR and the logical cpu, + * and MPIDR is the cpu hardware ID we needed to pack. + */ +#define cpu_physical_id(cpu) pack_mpidr(cpu_logical_map(cpu)) + /* * It's used from ACPI core in kdump to boot UP system with SMP kernel, * with this check the ACPI core will not override the CPU index diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 55d99d9..0b7c3a6 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -24,7 +24,6 @@ #include <linux/bootmem.h> #include <linux/smp.h> -#include <asm/smp_plat.h> #include <asm/cputype.h> #include <asm/cpu_ops.h> diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index 02e4839..e634b14 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; + return 0; + } + + return -EINVAL; +} + static int map_madt_entry(int type, u32 acpi_id) { unsigned long madt_end, entry; @@ -99,6 +131,9 @@ static int map_madt_entry(int type, u32 acpi_id) } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) { if (!map_lsapic_id(header, type, acpi_id, &phys_id)) break; + } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) { + if (!map_gicc_mpidr(header, type, acpi_id, &phys_id)) + break; } entry += header->length; } @@ -131,6 +166,8 @@ static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id) map_lsapic_id(header, type, acpi_id, &phys_id); else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) map_x2apic_id(header, type, acpi_id, &phys_id); + else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) + map_gicc_mpidr(header, type, acpi_id, &phys_id); exit: kfree(buffer.pointer);