| Message ID | 1407166105-17675-9-git-send-email-hanjun.guo@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Aug 04, 2014 at 04:28:15PM +0100, Hanjun Guo wrote: > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > index e877967..022f4ad 100644 > --- a/arch/arm64/include/asm/acpi.h > +++ b/arch/arm64/include/asm/acpi.h > @@ -14,6 +14,27 @@ > > /* Basic configuration for ACPI */ > #ifdef CONFIG_ACPI > +/* > + * ACPI 5.1 only has two explicit methods to > + * boot up SMP, PSCI and Parking protocol, > + * but the Parking protocol is only defined > + * for ARMv7 now, so make PSCI as the only > + * way for the SMP boot protocol before some > + * updates for the ACPI spec or the Parking > + * protocol spec. > + * > + * This enum is intend to make the boot method > + * scalable when above updates are happended, > + * which NOT means to support all of them. > + */ > +enum acpi_smp_boot_protocol { > + ACPI_SMP_BOOT_PSCI, > + ACPI_SMP_BOOT_PARKING_PROTOCOL, > + ACPI_SMP_BOOT_PROTOCOL_MAX > +}; > + > +enum acpi_smp_boot_protocol smp_boot_protocol(void); Since this is not a static function and ACPI-specific, could you prefix it with something like acpi (or arm64_acpi_ unless it gets too long)? > diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c > index d62d12f..05bc314 100644 > --- a/arch/arm64/kernel/cpu_ops.c > +++ b/arch/arm64/kernel/cpu_ops.c > @@ -16,11 +16,13 @@ > * along with this program. If not, see <http://www.gnu.org/licenses/>. > */ > > -#include <asm/cpu_ops.h> > -#include <asm/smp_plat.h> > #include <linux/errno.h> > #include <linux/of.h> > #include <linux/string.h> > +#include <linux/acpi.h> > + > +#include <asm/cpu_ops.h> > +#include <asm/smp_plat.h> > > extern const struct cpu_operations smp_spin_table_ops; > extern const struct cpu_operations cpu_psci_ops; > @@ -49,12 +51,44 @@ static const struct cpu_operations * __init cpu_get_ops(const char *name) > return NULL; > } > > +#ifdef CONFIG_ACPI > +/* > + * Get a cpu's boot method in the ACPI way. > + */ > +static char * __init acpi_get_cpu_boot_method(void) > +{ > + /* > + * For ACPI 5.1, only two kind of methods are provided, > + * Parking protocol and PSCI, but Parking protocol is > + * specified for ARMv7 only, so make PSCI as the only method > + * for SMP initialization before the ACPI spec or Parking > + * protocol spec is updated. > + */ > + switch (smp_boot_protocol()) { > + case ACPI_SMP_BOOT_PSCI: > + return "psci"; > + case ACPI_SMP_BOOT_PARKING_PROTOCOL: > + default: > + return NULL; > + } > +} Actually, do we even need to define smp_boot_protocol()? Is it used anywhere else apart from this patch (I still haven't gone through all patches)? > +#else > +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } > +#endif > + > /* > - * Read a cpu's enable method from the device tree and record it in cpu_ops. > + * Read a cpu's enable method and record it in cpu_ops. > */ > int __init cpu_read_ops(struct device_node *dn, int cpu) > { > - const char *enable_method = of_get_property(dn, "enable-method", NULL); > + const char *enable_method; > + > + if (!acpi_disabled) { > + enable_method = acpi_get_cpu_boot_method(); > + goto get_ops; Are we always guaranteed an enable_method here? You should have an if/else of ACPI vs DT and keep the if (!enable_method) check for both cases.
On 04/08/14 16:28, Hanjun Guo wrote: > ACPI 5.1 only has two explicit methods to boot up SMP, > PSCI and Parking protocol, but the Parking protocol is > only suitable for ARMv7 now, so make PSCI as the only way > for the SMP boot protocol before some updates for the > ACPI spec or the Parking protocol spec. > > Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> > Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org> > --- > arch/arm64/include/asm/acpi.h | 21 ++++++++++++++ > arch/arm64/include/asm/smp.h | 3 +- > arch/arm64/kernel/acpi.c | 9 ++++++ > arch/arm64/kernel/cpu_ops.c | 62 ++++++++++++++++++++++++++++++++++++----- > arch/arm64/kernel/smp.c | 27 +++++++++++++++++- > 5 files changed, 113 insertions(+), 9 deletions(-) > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > index e877967..022f4ad 100644 > --- a/arch/arm64/include/asm/acpi.h > +++ b/arch/arm64/include/asm/acpi.h > @@ -14,6 +14,27 @@ > > /* Basic configuration for ACPI */ > #ifdef CONFIG_ACPI > +/* > + * ACPI 5.1 only has two explicit methods to > + * boot up SMP, PSCI and Parking protocol, > + * but the Parking protocol is only defined > + * for ARMv7 now, so make PSCI as the only > + * way for the SMP boot protocol before some > + * updates for the ACPI spec or the Parking > + * protocol spec. > + * > + * This enum is intend to make the boot method > + * scalable when above updates are happended, > + * which NOT means to support all of them. > + */ > +enum acpi_smp_boot_protocol { > + ACPI_SMP_BOOT_PSCI, > + ACPI_SMP_BOOT_PARKING_PROTOCOL, > + ACPI_SMP_BOOT_PROTOCOL_MAX > +}; > + > +enum acpi_smp_boot_protocol smp_boot_protocol(void); > + > #define acpi_strict 1 /* No out-of-spec workarounds on ARM64 */ > extern int acpi_disabled; > extern int acpi_noirq; > diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h > index a498f2c..282932c2 100644 > --- a/arch/arm64/include/asm/smp.h > +++ b/arch/arm64/include/asm/smp.h > @@ -39,7 +39,8 @@ extern void show_ipi_list(struct seq_file *p, int prec); > extern void handle_IPI(int ipinr, struct pt_regs *regs); > > /* > - * Setup the set of possible CPUs (via set_cpu_possible) > + * Discover the set of possible CPUs and determine their > + * SMP operations. > */ > extern void smp_init_cpus(void); > > diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c > index 9e07d99..8a54b4e 100644 > --- a/arch/arm64/kernel/acpi.c > +++ b/arch/arm64/kernel/acpi.c > @@ -170,6 +170,15 @@ static int __init acpi_parse_madt_gic_cpu_interface_entries(void) > return 0; > } > > +/* Protocol to bring up secondary CPUs */ > +enum acpi_smp_boot_protocol smp_boot_protocol(void) > +{ > + if (acpi_psci_present()) > + return ACPI_SMP_BOOT_PSCI; > + else > + return ACPI_SMP_BOOT_PARKING_PROTOCOL; > +} > + Which do you need this here ? Can't you use acpi_psci_present directly in acpi_get_cpu_boot_method ? > static int __init acpi_parse_fadt(struct acpi_table_header *table) > { > struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table; > diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c > index d62d12f..05bc314 100644 > --- a/arch/arm64/kernel/cpu_ops.c > +++ b/arch/arm64/kernel/cpu_ops.c > @@ -16,11 +16,13 @@ > * along with this program. If not, see <http://www.gnu.org/licenses/>. > */ > > -#include <asm/cpu_ops.h> > -#include <asm/smp_plat.h> > #include <linux/errno.h> > #include <linux/of.h> > #include <linux/string.h> > +#include <linux/acpi.h> > + > +#include <asm/cpu_ops.h> > +#include <asm/smp_plat.h> > > extern const struct cpu_operations smp_spin_table_ops; > extern const struct cpu_operations cpu_psci_ops; > @@ -49,12 +51,44 @@ static const struct cpu_operations * __init cpu_get_ops(const char *name) > return NULL; > } > > +#ifdef CONFIG_ACPI > +/* > + * Get a cpu's boot method in the ACPI way. > + */ > +static char * __init acpi_get_cpu_boot_method(void) > +{ > + /* > + * For ACPI 5.1, only two kind of methods are provided, > + * Parking protocol and PSCI, but Parking protocol is > + * specified for ARMv7 only, so make PSCI as the only method > + * for SMP initialization before the ACPI spec or Parking > + * protocol spec is updated. > + */ > + switch (smp_boot_protocol()) { > + case ACPI_SMP_BOOT_PSCI: > + return "psci"; > + case ACPI_SMP_BOOT_PARKING_PROTOCOL: > + default: > + return NULL; > + } Use acpi_psci_present as mentioned above. > +} > +#else > +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } > +#endif > + > /* > - * Read a cpu's enable method from the device tree and record it in cpu_ops. > + * Read a cpu's enable method and record it in cpu_ops. > */ > int __init cpu_read_ops(struct device_node *dn, int cpu) > { > - const char *enable_method = of_get_property(dn, "enable-method", NULL); > + const char *enable_method; > + > + if (!acpi_disabled) { > + enable_method = acpi_get_cpu_boot_method(); > + goto get_ops; > + } > + > + enable_method = of_get_property(dn, "enable-method", NULL); > if (!enable_method) { > /* > * The boot CPU may not have an enable method (e.g. when > @@ -66,10 +100,17 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) > return -ENOENT; > } > > +get_ops: > cpu_ops[cpu] = cpu_get_ops(enable_method); > if (!cpu_ops[cpu]) { > - pr_warn("%s: unsupported enable-method property: %s\n", > - dn->full_name, enable_method); > + if (acpi_disabled) { > + pr_warn("%s: unsupported enable-method property: %s\n", > + dn->full_name, enable_method); > + } else { > + pr_warn("CPU %d: boot protocol unsupported or unknown\n", > + cpu); > + } > + > return -EOPNOTSUPP; > } > > @@ -78,7 +119,14 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) > > void __init cpu_read_bootcpu_ops(void) > { > - struct device_node *dn = of_get_cpu_node(0, NULL); > + struct device_node *dn; > + > + if (!acpi_disabled) { > + cpu_read_ops(NULL, 0); > + return; > + } > + Again not good to mix ACPI in DT functions forcing you to pass device_node ptr as NULL, better to separate this. Once you gather all this !acpi_disabled case, you can create appropriate abstractions to be used in setup.c E.g. here you check !acpi_disabled and pass NULL for DT node to cpu_read_ops and hence again you check for !acpi_disabled in cpu_read_ops. So you need first identify all these checks and put in one place to understand well how you can refactor existing code to avoid these multiple checks. > + dn = of_get_cpu_node(0, NULL); > if (!dn) { > pr_err("Failed to find device node for boot cpu\n"); > return; > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > index 8f1d37c..e21bbc9 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -315,7 +315,7 @@ 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 void __init of_smp_init_cpus(void) > { > struct device_node *dn = NULL; > unsigned int i, cpu = 1; > @@ -418,6 +418,31 @@ next: > set_cpu_possible(i, true); > } > > +/* > + * 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; > + > + for_each_possible_cpu(cpu) { > + if (cpu_read_ops(NULL, cpu) != 0) > + continue; > + > + cpu_ops[cpu]->cpu_init(NULL, cpu); > + } > +} > + > +void __init smp_init_cpus(void) > +{ > + if (acpi_disabled) > + of_smp_init_cpus(); > + else > + acpi_smp_init_cpus(); > +} > + > void __init smp_prepare_cpus(unsigned int max_cpus) > { > int err; >
Hi Hanjun, On Mon, 2014-08-04 at 23:28 +0800, Hanjun Guo wrote: > --- a/arch/arm64/include/asm/acpi.h > +++ b/arch/arm64/include/asm/acpi.h > @@ -14,6 +14,27 @@ > > /* Basic configuration for ACPI */ > #ifdef CONFIG_ACPI By having this preprocessor conditional in the header leads to a proliferation of preprocessor conditionals since any code that includes this header will also need to have preprocessor conditionals. Another down side of having this is that this code will not get a build test for builds with CONFIG_ACPI=n. > +/* > + * ACPI 5.1 only has two explicit methods to > + * boot up SMP, PSCI and Parking protocol, > + * but the Parking protocol is only defined > + * for ARMv7 now, so make PSCI as the only > + * way for the SMP boot protocol before some > + * updates for the ACPI spec or the Parking > + * protocol spec. > + * > + * This enum is intend to make the boot method > + * scalable when above updates are happended, > + * which NOT means to support all of them. > + */ > +enum acpi_smp_boot_protocol { > + ACPI_SMP_BOOT_PSCI, > + ACPI_SMP_BOOT_PARKING_PROTOCOL, > + ACPI_SMP_BOOT_PROTOCOL_MAX > +}; > + > +enum acpi_smp_boot_protocol smp_boot_protocol(void); The name smp_boot_protocol() seems like it would be a generic routine, but it is acpi specific. Maybe: enum acpi_boot_protocol_type {...}; enum acpi_boot_protocol_type acpi_boot_protocol(void); > --- a/arch/arm64/kernel/cpu_ops.c > +++ b/arch/arm64/kernel/cpu_ops.c > @@ -49,12 +51,44 @@ static const struct cpu_operations * __init cpu_get_ops(const char *name) > return NULL; > } > > +#ifdef CONFIG_ACPI > +/* > + * Get a cpu's boot method in the ACPI way. > + */ > +static char * __init acpi_get_cpu_boot_method(void) > +{ > + /* > + * For ACPI 5.1, only two kind of methods are provided, > + * Parking protocol and PSCI, but Parking protocol is > + * specified for ARMv7 only, so make PSCI as the only method > + * for SMP initialization before the ACPI spec or Parking > + * protocol spec is updated. > + */ > + switch (smp_boot_protocol()) { > + case ACPI_SMP_BOOT_PSCI: > + return "psci"; > + case ACPI_SMP_BOOT_PARKING_PROTOCOL: > + default: > + return NULL; > + } > +} > +#else > +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } > +#endif Since this is inside a C source file, the inline keyword isn't needed since the optimizer will inline regardless. With that said, I think it would be cleaner to have this as: static char * __init acpi_get_cpu_boot_method(void) { #ifdef CONFIG_ACPI return NULL; #else ... #endif } Or better to make smp_boot_protocol() callable regardless of CONFIG_ACPI and then no preprocessor conditionals at all would be needed. > + > /* > - * Read a cpu's enable method from the device tree and record it in cpu_ops. > + * Read a cpu's enable method and record it in cpu_ops. > */ > int __init cpu_read_ops(struct device_node *dn, int cpu) > { > - const char *enable_method = of_get_property(dn, "enable-method", NULL); > + const char *enable_method; > + > + if (!acpi_disabled) { > + enable_method = acpi_get_cpu_boot_method(); > + goto get_ops; > + } > + > + enable_method = of_get_property(dn, "enable-method", NULL); > if (!enable_method) { > /* > * The boot CPU may not have an enable method (e.g. when > @@ -66,10 +100,17 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) > return -ENOENT; > } > > +get_ops: > cpu_ops[cpu] = cpu_get_ops(enable_method); > if (!cpu_ops[cpu]) { > - pr_warn("%s: unsupported enable-method property: %s\n", > - dn->full_name, enable_method); > + if (acpi_disabled) { > + pr_warn("%s: unsupported enable-method property: %s\n", > + dn->full_name, enable_method); > + } else { > + pr_warn("CPU %d: boot protocol unsupported or unknown\n", > + cpu); > + } > + Can't we have this more integrated, maybe something like this? enable_method = acpi_disabled ? of_get_property(dn, "enable-method", NULL) : acpi_get_cpu_boot_method(); message = acpi_disabled ? dn->full_name : ""; ... pr_warn("CPU %d: %s unsupported enable-method property: %s\n", cpu, message, enable_method) -Geoff
On 2014-8-18 22:27, Catalin Marinas wrote: > On Mon, Aug 04, 2014 at 04:28:15PM +0100, Hanjun Guo wrote: >> diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h >> index e877967..022f4ad 100644 >> --- a/arch/arm64/include/asm/acpi.h >> +++ b/arch/arm64/include/asm/acpi.h >> @@ -14,6 +14,27 @@ >> >> /* Basic configuration for ACPI */ >> #ifdef CONFIG_ACPI >> +/* >> + * ACPI 5.1 only has two explicit methods to >> + * boot up SMP, PSCI and Parking protocol, >> + * but the Parking protocol is only defined >> + * for ARMv7 now, so make PSCI as the only >> + * way for the SMP boot protocol before some >> + * updates for the ACPI spec or the Parking >> + * protocol spec. >> + * >> + * This enum is intend to make the boot method >> + * scalable when above updates are happended, >> + * which NOT means to support all of them. >> + */ >> +enum acpi_smp_boot_protocol { >> + ACPI_SMP_BOOT_PSCI, >> + ACPI_SMP_BOOT_PARKING_PROTOCOL, >> + ACPI_SMP_BOOT_PROTOCOL_MAX >> +}; >> + >> +enum acpi_smp_boot_protocol smp_boot_protocol(void); > > Since this is not a static function and ACPI-specific, could you prefix > it with something like acpi (or arm64_acpi_ unless it gets too long)? > >> diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c >> index d62d12f..05bc314 100644 >> --- a/arch/arm64/kernel/cpu_ops.c >> +++ b/arch/arm64/kernel/cpu_ops.c >> @@ -16,11 +16,13 @@ >> * along with this program. If not, see <http://www.gnu.org/licenses/>. >> */ >> >> -#include <asm/cpu_ops.h> >> -#include <asm/smp_plat.h> >> #include <linux/errno.h> >> #include <linux/of.h> >> #include <linux/string.h> >> +#include <linux/acpi.h> >> + >> +#include <asm/cpu_ops.h> >> +#include <asm/smp_plat.h> >> >> extern const struct cpu_operations smp_spin_table_ops; >> extern const struct cpu_operations cpu_psci_ops; >> @@ -49,12 +51,44 @@ static const struct cpu_operations * __init cpu_get_ops(const char *name) >> return NULL; >> } >> >> +#ifdef CONFIG_ACPI >> +/* >> + * Get a cpu's boot method in the ACPI way. >> + */ >> +static char * __init acpi_get_cpu_boot_method(void) >> +{ >> + /* >> + * For ACPI 5.1, only two kind of methods are provided, >> + * Parking protocol and PSCI, but Parking protocol is >> + * specified for ARMv7 only, so make PSCI as the only method >> + * for SMP initialization before the ACPI spec or Parking >> + * protocol spec is updated. >> + */ >> + switch (smp_boot_protocol()) { >> + case ACPI_SMP_BOOT_PSCI: >> + return "psci"; >> + case ACPI_SMP_BOOT_PARKING_PROTOCOL: >> + default: >> + return NULL; >> + } >> +} > > Actually, do we even need to define smp_boot_protocol()? Is it used > anywhere else apart from this patch (I still haven't gone through all > patches)? It is just used in this patch. I think we can make the ACPI boot protocol scalable in this way, if we support another boot protocol in ACPI in the future, we can easily update the function to support it, does it make sense? > >> +#else >> +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } >> +#endif >> + >> /* >> - * Read a cpu's enable method from the device tree and record it in cpu_ops. >> + * Read a cpu's enable method and record it in cpu_ops. >> */ >> int __init cpu_read_ops(struct device_node *dn, int cpu) >> { >> - const char *enable_method = of_get_property(dn, "enable-method", NULL); >> + const char *enable_method; >> + >> + if (!acpi_disabled) { >> + enable_method = acpi_get_cpu_boot_method(); >> + goto get_ops; > > Are we always guaranteed an enable_method here? You should have an > if/else of ACPI vs DT and keep the if (!enable_method) check for both > cases. ok, I will fix it. Thanks Hanjun
On 2014-8-19 2:34, Sudeep Holla wrote: > On 04/08/14 16:28, Hanjun Guo wrote: [...] >> /* Basic configuration for ACPI */ >> #ifdef CONFIG_ACPI >> +/* >> + * ACPI 5.1 only has two explicit methods to >> + * boot up SMP, PSCI and Parking protocol, >> + * but the Parking protocol is only defined >> + * for ARMv7 now, so make PSCI as the only >> + * way for the SMP boot protocol before some >> + * updates for the ACPI spec or the Parking >> + * protocol spec. >> + * >> + * This enum is intend to make the boot method >> + * scalable when above updates are happended, >> + * which NOT means to support all of them. >> + */ >> +enum acpi_smp_boot_protocol { >> + ACPI_SMP_BOOT_PSCI, >> + ACPI_SMP_BOOT_PARKING_PROTOCOL, >> + ACPI_SMP_BOOT_PROTOCOL_MAX >> +}; >> + >> +enum acpi_smp_boot_protocol smp_boot_protocol(void); >> + [...] >> +/* Protocol to bring up secondary CPUs */ >> +enum acpi_smp_boot_protocol smp_boot_protocol(void) >> +{ >> + if (acpi_psci_present()) >> + return ACPI_SMP_BOOT_PSCI; >> + else >> + return ACPI_SMP_BOOT_PARKING_PROTOCOL; >> +} >> + > > Which do you need this here ? Can't you use acpi_psci_present directly > in acpi_get_cpu_boot_method ? My intent was to make the code scalable if we introduce another (or more) boot protocol in ACPI, does it make sense to you? > >> static int __init acpi_parse_fadt(struct acpi_table_header *table) >> { >> struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table; >> diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c >> index d62d12f..05bc314 100644 >> --- a/arch/arm64/kernel/cpu_ops.c >> +++ b/arch/arm64/kernel/cpu_ops.c >> @@ -16,11 +16,13 @@ >> * along with this program. If not, see <http://www.gnu.org/licenses/>. >> */ >> >> -#include <asm/cpu_ops.h> >> -#include <asm/smp_plat.h> >> #include <linux/errno.h> >> #include <linux/of.h> >> #include <linux/string.h> >> +#include <linux/acpi.h> >> + >> +#include <asm/cpu_ops.h> >> +#include <asm/smp_plat.h> >> >> extern const struct cpu_operations smp_spin_table_ops; >> extern const struct cpu_operations cpu_psci_ops; >> @@ -49,12 +51,44 @@ static const struct cpu_operations * __init >> cpu_get_ops(const char *name) >> return NULL; >> } >> >> +#ifdef CONFIG_ACPI >> +/* >> + * Get a cpu's boot method in the ACPI way. >> + */ >> +static char * __init acpi_get_cpu_boot_method(void) >> +{ >> + /* >> + * For ACPI 5.1, only two kind of methods are provided, >> + * Parking protocol and PSCI, but Parking protocol is >> + * specified for ARMv7 only, so make PSCI as the only method >> + * for SMP initialization before the ACPI spec or Parking >> + * protocol spec is updated. >> + */ >> + switch (smp_boot_protocol()) { >> + case ACPI_SMP_BOOT_PSCI: >> + return "psci"; >> + case ACPI_SMP_BOOT_PARKING_PROTOCOL: >> + default: >> + return NULL; >> + } > > Use acpi_psci_present as mentioned above. > >> +} >> +#else >> +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } >> +#endif >> + >> /* >> - * Read a cpu's enable method from the device tree and record it in cpu_ops. >> + * Read a cpu's enable method and record it in cpu_ops. >> */ >> int __init cpu_read_ops(struct device_node *dn, int cpu) >> { >> - const char *enable_method = of_get_property(dn, "enable-method", NULL); >> + const char *enable_method; >> + >> + if (!acpi_disabled) { >> + enable_method = acpi_get_cpu_boot_method(); >> + goto get_ops; >> + } >> + >> + enable_method = of_get_property(dn, "enable-method", NULL); >> if (!enable_method) { >> /* >> * The boot CPU may not have an enable method (e.g. when >> @@ -66,10 +100,17 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) >> return -ENOENT; >> } >> >> +get_ops: >> cpu_ops[cpu] = cpu_get_ops(enable_method); >> if (!cpu_ops[cpu]) { >> - pr_warn("%s: unsupported enable-method property: %s\n", >> - dn->full_name, enable_method); >> + if (acpi_disabled) { >> + pr_warn("%s: unsupported enable-method property: %s\n", >> + dn->full_name, enable_method); >> + } else { >> + pr_warn("CPU %d: boot protocol unsupported or unknown\n", >> + cpu); >> + } >> + >> return -EOPNOTSUPP; >> } >> >> @@ -78,7 +119,14 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) >> >> void __init cpu_read_bootcpu_ops(void) >> { >> - struct device_node *dn = of_get_cpu_node(0, NULL); >> + struct device_node *dn; >> + >> + if (!acpi_disabled) { >> + cpu_read_ops(NULL, 0); >> + return; >> + } >> + > > Again not good to mix ACPI in DT functions forcing you to pass > device_node ptr as NULL, better to separate this. I separate them in the first version, and combine tham as Geoff suggested for scalable reasons. > Once you gather all > this !acpi_disabled case, you can create appropriate abstractions to be > used in setup.c > > E.g. here you check !acpi_disabled and pass NULL for DT node to > cpu_read_ops and hence again you check for !acpi_disabled in > cpu_read_ops. So you need first identify all these checks and put in one > place to understand well how you can refactor existing code to avoid > these multiple checks. I will remove the multiple acpi_disabled checks and refactor the code. Thanks Hanjun
On 2014-8-19 2:56, Geoff Levand wrote: > Hi Hanjun, Hi Geoff, > > On Mon, 2014-08-04 at 23:28 +0800, Hanjun Guo wrote: >> --- a/arch/arm64/include/asm/acpi.h >> +++ b/arch/arm64/include/asm/acpi.h >> @@ -14,6 +14,27 @@ >> >> /* Basic configuration for ACPI */ >> #ifdef CONFIG_ACPI > > By having this preprocessor conditional in the header leads > to a proliferation of preprocessor conditionals since any > code that includes this header will also need to have > preprocessor conditionals. Another down side of having > this is that this code will not get a build test for > builds with CONFIG_ACPI=n. I will move some definitions out of preprocessor conditional and introduce some stub function when CONFIG_ACPI is disabled, then I think I can remove all the preprocessor conditionals in .c file. > >> +/* >> + * ACPI 5.1 only has two explicit methods to >> + * boot up SMP, PSCI and Parking protocol, >> + * but the Parking protocol is only defined >> + * for ARMv7 now, so make PSCI as the only >> + * way for the SMP boot protocol before some >> + * updates for the ACPI spec or the Parking >> + * protocol spec. >> + * >> + * This enum is intend to make the boot method >> + * scalable when above updates are happended, >> + * which NOT means to support all of them. >> + */ >> +enum acpi_smp_boot_protocol { >> + ACPI_SMP_BOOT_PSCI, >> + ACPI_SMP_BOOT_PARKING_PROTOCOL, >> + ACPI_SMP_BOOT_PROTOCOL_MAX >> +}; >> + >> +enum acpi_smp_boot_protocol smp_boot_protocol(void); > > The name smp_boot_protocol() seems like it would be a generic > routine, but it is acpi specific. Maybe: > > enum acpi_boot_protocol_type {...}; > > enum acpi_boot_protocol_type acpi_boot_protocol(void); Agreed. > >> --- a/arch/arm64/kernel/cpu_ops.c >> +++ b/arch/arm64/kernel/cpu_ops.c >> @@ -49,12 +51,44 @@ static const struct cpu_operations * __init cpu_get_ops(const char *name) >> return NULL; >> } >> >> +#ifdef CONFIG_ACPI >> +/* >> + * Get a cpu's boot method in the ACPI way. >> + */ >> +static char * __init acpi_get_cpu_boot_method(void) >> +{ >> + /* >> + * For ACPI 5.1, only two kind of methods are provided, >> + * Parking protocol and PSCI, but Parking protocol is >> + * specified for ARMv7 only, so make PSCI as the only method >> + * for SMP initialization before the ACPI spec or Parking >> + * protocol spec is updated. >> + */ >> + switch (smp_boot_protocol()) { >> + case ACPI_SMP_BOOT_PSCI: >> + return "psci"; >> + case ACPI_SMP_BOOT_PARKING_PROTOCOL: >> + default: >> + return NULL; >> + } >> +} >> +#else >> +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } >> +#endif > > Since this is inside a C source file, the inline keyword > isn't needed since the optimizer will inline regardless. > > With that said, I think it would be cleaner to have this > as: > > static char * __init acpi_get_cpu_boot_method(void) > { > #ifdef CONFIG_ACPI > return NULL; > #else > ... > #endif > } > > Or better to make smp_boot_protocol() callable regardless > of CONFIG_ACPI and then no preprocessor conditionals at all > would be needed. > >> + >> /* >> - * Read a cpu's enable method from the device tree and record it in cpu_ops. >> + * Read a cpu's enable method and record it in cpu_ops. >> */ >> int __init cpu_read_ops(struct device_node *dn, int cpu) >> { >> - const char *enable_method = of_get_property(dn, "enable-method", NULL); >> + const char *enable_method; >> + >> + if (!acpi_disabled) { >> + enable_method = acpi_get_cpu_boot_method(); >> + goto get_ops; >> + } >> + >> + enable_method = of_get_property(dn, "enable-method", NULL); >> if (!enable_method) { >> /* >> * The boot CPU may not have an enable method (e.g. when >> @@ -66,10 +100,17 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) >> return -ENOENT; >> } >> >> +get_ops: >> cpu_ops[cpu] = cpu_get_ops(enable_method); >> if (!cpu_ops[cpu]) { >> - pr_warn("%s: unsupported enable-method property: %s\n", >> - dn->full_name, enable_method); >> + if (acpi_disabled) { >> + pr_warn("%s: unsupported enable-method property: %s\n", >> + dn->full_name, enable_method); >> + } else { >> + pr_warn("CPU %d: boot protocol unsupported or unknown\n", >> + cpu); >> + } >> + > > Can't we have this more integrated, maybe something like this? > > enable_method = acpi_disabled ? of_get_property(dn, "enable-method", NULL) > : acpi_get_cpu_boot_method(); I like this :) > message = acpi_disabled ? dn->full_name : ""; > > ... > > pr_warn("CPU %d: %s unsupported enable-method property: %s\n", > cpu, message, enable_method) In ACPI, there is no enable-method property, it is a term from, so I think the message printed can be separated. Thanks Hanjun
Hi Hanjun, On Tue, 2014-08-19 at 20:11 +0800, Hanjun Guo wrote: > On 2014-8-19 2:56, Geoff Levand wrote: > > message = acpi_disabled ? dn->full_name : ""; > > > > ... > > > > pr_warn("CPU %d: %s unsupported enable-method property: %s\n", > > cpu, message, enable_method) > > In ACPI, there is no enable-method property, it is a term from, so I think the > message printed can be separated. I think it better to have a single message that can cover all than to have separate messages. Wouldn't the enable method be "acpi-parking" or "acpi-psci"? Then something like this would work: pr_warn("CPU %d: %s Unsupported enable method: %s\n", cpu, message, enable_method); -Geoff
On 2014-8-20 3:25, Geoff Levand wrote: > Hi Hanjun, > > On Tue, 2014-08-19 at 20:11 +0800, Hanjun Guo wrote: >> On 2014-8-19 2:56, Geoff Levand wrote: > >>> message = acpi_disabled ? dn->full_name : ""; >>> >>> ... >>> >>> pr_warn("CPU %d: %s unsupported enable-method property: %s\n", >>> cpu, message, enable_method) >> >> In ACPI, there is no enable-method property, it is a term from, so I think the >> message printed can be separated. > > I think it better to have a single message that can cover all > than to have separate messages. Wouldn't the enable method be > "acpi-parking" or "acpi-psci"? Then something like this would > work: > > pr_warn("CPU %d: %s Unsupported enable method: %s\n", cpu, message, enable_method); Thanks for the suggestion, I will update it in next version. Thanks Hanjun
On Tue, Aug 19, 2014 at 09:32:25AM +0100, Hanjun Guo wrote: > On 2014-8-18 22:27, Catalin Marinas wrote: > > On Mon, Aug 04, 2014 at 04:28:15PM +0100, Hanjun Guo wrote: > >> +#ifdef CONFIG_ACPI > >> +/* > >> + * Get a cpu's boot method in the ACPI way. > >> + */ > >> +static char * __init acpi_get_cpu_boot_method(void) > >> +{ > >> + /* > >> + * For ACPI 5.1, only two kind of methods are provided, > >> + * Parking protocol and PSCI, but Parking protocol is > >> + * specified for ARMv7 only, so make PSCI as the only method > >> + * for SMP initialization before the ACPI spec or Parking > >> + * protocol spec is updated. > >> + */ > >> + switch (smp_boot_protocol()) { > >> + case ACPI_SMP_BOOT_PSCI: > >> + return "psci"; > >> + case ACPI_SMP_BOOT_PARKING_PROTOCOL: > >> + default: > >> + return NULL; > >> + } > >> +} > > > > Actually, do we even need to define smp_boot_protocol()? Is it used > > anywhere else apart from this patch (I still haven't gone through all > > patches)? > > It is just used in this patch. I think we can make the ACPI boot protocol > scalable in this way, if we support another boot protocol in ACPI in the > future, we can easily update the function to support it, does it make sense? Not really. You just add additional code, enums, functions when all you do is check for acpi_psci_present() (or whatever new protocol you would get). If the enum is never going to be used outside this file, don't bother with additional functions. BTW, it would be nicer if the acpi related functions are contained in as fewer files as possible. So here you could keep acpi_get_cpu_boot_method() in the acpi.c file. It only returns a string.
On 2014-8-20 22:52, Catalin Marinas wrote: > On Tue, Aug 19, 2014 at 09:32:25AM +0100, Hanjun Guo wrote: >> On 2014-8-18 22:27, Catalin Marinas wrote: >>> On Mon, Aug 04, 2014 at 04:28:15PM +0100, Hanjun Guo wrote: >>>> +#ifdef CONFIG_ACPI >>>> +/* >>>> + * Get a cpu's boot method in the ACPI way. >>>> + */ >>>> +static char * __init acpi_get_cpu_boot_method(void) >>>> +{ >>>> + /* >>>> + * For ACPI 5.1, only two kind of methods are provided, >>>> + * Parking protocol and PSCI, but Parking protocol is >>>> + * specified for ARMv7 only, so make PSCI as the only method >>>> + * for SMP initialization before the ACPI spec or Parking >>>> + * protocol spec is updated. >>>> + */ >>>> + switch (smp_boot_protocol()) { >>>> + case ACPI_SMP_BOOT_PSCI: >>>> + return "psci"; >>>> + case ACPI_SMP_BOOT_PARKING_PROTOCOL: >>>> + default: >>>> + return NULL; >>>> + } >>>> +} >>> >>> Actually, do we even need to define smp_boot_protocol()? Is it used >>> anywhere else apart from this patch (I still haven't gone through all >>> patches)? >> >> It is just used in this patch. I think we can make the ACPI boot protocol >> scalable in this way, if we support another boot protocol in ACPI in the >> future, we can easily update the function to support it, does it make sense? > > Not really. You just add additional code, enums, functions when all you > do is check for acpi_psci_present() (or whatever new protocol you would > get). If the enum is never going to be used outside this file, don't > bother with additional functions. > > BTW, it would be nicer if the acpi related functions are contained in as > fewer files as possible. So here you could keep > acpi_get_cpu_boot_method() in the acpi.c file. It only returns a string. ok, I will update them. Thanks Hanjun
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index e877967..022f4ad 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -14,6 +14,27 @@ /* Basic configuration for ACPI */ #ifdef CONFIG_ACPI +/* + * ACPI 5.1 only has two explicit methods to + * boot up SMP, PSCI and Parking protocol, + * but the Parking protocol is only defined + * for ARMv7 now, so make PSCI as the only + * way for the SMP boot protocol before some + * updates for the ACPI spec or the Parking + * protocol spec. + * + * This enum is intend to make the boot method + * scalable when above updates are happended, + * which NOT means to support all of them. + */ +enum acpi_smp_boot_protocol { + ACPI_SMP_BOOT_PSCI, + ACPI_SMP_BOOT_PARKING_PROTOCOL, + ACPI_SMP_BOOT_PROTOCOL_MAX +}; + +enum acpi_smp_boot_protocol smp_boot_protocol(void); + #define acpi_strict 1 /* No out-of-spec workarounds on ARM64 */ extern int acpi_disabled; extern int acpi_noirq; diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index a498f2c..282932c2 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -39,7 +39,8 @@ extern void show_ipi_list(struct seq_file *p, int prec); extern void handle_IPI(int ipinr, struct pt_regs *regs); /* - * Setup the set of possible CPUs (via set_cpu_possible) + * Discover the set of possible CPUs and determine their + * SMP operations. */ extern void smp_init_cpus(void); diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 9e07d99..8a54b4e 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -170,6 +170,15 @@ static int __init acpi_parse_madt_gic_cpu_interface_entries(void) return 0; } +/* Protocol to bring up secondary CPUs */ +enum acpi_smp_boot_protocol smp_boot_protocol(void) +{ + if (acpi_psci_present()) + return ACPI_SMP_BOOT_PSCI; + else + return ACPI_SMP_BOOT_PARKING_PROTOCOL; +} + static int __init acpi_parse_fadt(struct acpi_table_header *table) { struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table; diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c index d62d12f..05bc314 100644 --- a/arch/arm64/kernel/cpu_ops.c +++ b/arch/arm64/kernel/cpu_ops.c @@ -16,11 +16,13 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ -#include <asm/cpu_ops.h> -#include <asm/smp_plat.h> #include <linux/errno.h> #include <linux/of.h> #include <linux/string.h> +#include <linux/acpi.h> + +#include <asm/cpu_ops.h> +#include <asm/smp_plat.h> extern const struct cpu_operations smp_spin_table_ops; extern const struct cpu_operations cpu_psci_ops; @@ -49,12 +51,44 @@ static const struct cpu_operations * __init cpu_get_ops(const char *name) return NULL; } +#ifdef CONFIG_ACPI +/* + * Get a cpu's boot method in the ACPI way. + */ +static char * __init acpi_get_cpu_boot_method(void) +{ + /* + * For ACPI 5.1, only two kind of methods are provided, + * Parking protocol and PSCI, but Parking protocol is + * specified for ARMv7 only, so make PSCI as the only method + * for SMP initialization before the ACPI spec or Parking + * protocol spec is updated. + */ + switch (smp_boot_protocol()) { + case ACPI_SMP_BOOT_PSCI: + return "psci"; + case ACPI_SMP_BOOT_PARKING_PROTOCOL: + default: + return NULL; + } +} +#else +static inline char * __init acpi_get_cpu_boot_method(void) { return NULL; } +#endif + /* - * Read a cpu's enable method from the device tree and record it in cpu_ops. + * Read a cpu's enable method and record it in cpu_ops. */ int __init cpu_read_ops(struct device_node *dn, int cpu) { - const char *enable_method = of_get_property(dn, "enable-method", NULL); + const char *enable_method; + + if (!acpi_disabled) { + enable_method = acpi_get_cpu_boot_method(); + goto get_ops; + } + + enable_method = of_get_property(dn, "enable-method", NULL); if (!enable_method) { /* * The boot CPU may not have an enable method (e.g. when @@ -66,10 +100,17 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) return -ENOENT; } +get_ops: cpu_ops[cpu] = cpu_get_ops(enable_method); if (!cpu_ops[cpu]) { - pr_warn("%s: unsupported enable-method property: %s\n", - dn->full_name, enable_method); + if (acpi_disabled) { + pr_warn("%s: unsupported enable-method property: %s\n", + dn->full_name, enable_method); + } else { + pr_warn("CPU %d: boot protocol unsupported or unknown\n", + cpu); + } + return -EOPNOTSUPP; } @@ -78,7 +119,14 @@ int __init cpu_read_ops(struct device_node *dn, int cpu) void __init cpu_read_bootcpu_ops(void) { - struct device_node *dn = of_get_cpu_node(0, NULL); + struct device_node *dn; + + if (!acpi_disabled) { + cpu_read_ops(NULL, 0); + return; + } + + dn = of_get_cpu_node(0, NULL); if (!dn) { pr_err("Failed to find device node for boot cpu\n"); return; diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 8f1d37c..e21bbc9 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -315,7 +315,7 @@ 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 void __init of_smp_init_cpus(void) { struct device_node *dn = NULL; unsigned int i, cpu = 1; @@ -418,6 +418,31 @@ next: set_cpu_possible(i, true); } +/* + * 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; + + for_each_possible_cpu(cpu) { + if (cpu_read_ops(NULL, cpu) != 0) + continue; + + cpu_ops[cpu]->cpu_init(NULL, cpu); + } +} + +void __init smp_init_cpus(void) +{ + if (acpi_disabled) + of_smp_init_cpus(); + else + acpi_smp_init_cpus(); +} + void __init smp_prepare_cpus(unsigned int max_cpus) { int err;