On Mon, 2009-12-21 at 03:30 +0800, Alex Chiang wrote: > We discovered that at least one machine (HP Envy), methods in the DSDT > attempt to call external methods defined in a dynamically loaded SSDT. > > Unfortunately, the DSDT methods we are trying to call are part of the > EC initialization, which happens very early, and the the dynamic SSDT > is only loaded when a processor _PDC method runs much later. > > This results in namespace lookup errors for the (as of yet) undefined > methods. > > Since Windows doesn't have any issues with this machine, we take it > as a hint that they must be evaluating _PDC much earlier than we are. > > Thus, the proper thing for Linux to do should be to match the Windows > implementation more closely. > > Provide a mechanism to call _PDC before we enable the EC. Doing so loads > the dynamic tables, and allows the EC to be enabled correctly. > > The ACPI processor driver will still evaluate _PDC in its .add() method > to cover the hotplug case. > > Resolves: http://bugzilla.kernel.org/show_bug.cgi?id=14824 > > Cc: ming.m.lin@xxxxxxxxx > Signed-off-by: Alex Chiang <achiang@xxxxxx> > --- > > drivers/acpi/Makefile | 1 > drivers/acpi/bus.c | 2 + > drivers/acpi/internal.h | 1 > drivers/acpi/processor_core.c | 69 -------------------------- > drivers/acpi/processor_pdc.c | 108 +++++++++++++++++++++++++++++++++++++++++ > include/acpi/processor.h | 3 + > 6 files changed, 115 insertions(+), 69 deletions(-) > create mode 100644 drivers/acpi/processor_pdc.c > > diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile > index c7b10b4..66cc3f3 100644 > --- a/drivers/acpi/Makefile > +++ b/drivers/acpi/Makefile > @@ -32,6 +32,7 @@ acpi-$(CONFIG_ACPI_SLEEP) += proc.o > # > acpi-y += bus.o glue.o > acpi-y += scan.o > +acpi-y += processor_pdc.o > acpi-y += ec.o > acpi-$(CONFIG_ACPI_DOCK) += dock.o > acpi-y += pci_root.o pci_link.o pci_irq.o pci_bind.o > diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c > index 65f7e33..0bdf24a 100644 > --- a/drivers/acpi/bus.c > +++ b/drivers/acpi/bus.c > @@ -888,6 +888,8 @@ static int __init acpi_bus_init(void) > goto error1; > } > > + acpi_early_processor_set_pdc(); acpi_bus_init(...) { acpi_ec_ecdt_probe(); acpi_initialize_objects(ACPI_FULL_INITIALIZATION); acpi_early_processor_set_pdc(); acpi_boot_ec_enable(); } EC space handler may be installed in acpi_ec_ecdt_probe or acpi_boot_ec_enable. In your machine(HP Envy), EC space handler is installed in acpi_boot_ec_enable. It seems that this patch does not fix the problem if EC space hanlder is installed in acpi_ec_ecdt_probe, right? But clearly, we can not put acpi_early_processor_set_pdc before acpi_ec_ecdt_probe because ACPI namespace objects have not been initialized yet at that time. Looks like a "chicken or the egg" problem. Which came first, the chicken or the egg? Lin Ming > + > /* > * Maybe EC region is required at bus_scan/acpi_get_devices. So it > * is necessary to enable it as early as possible. > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 074cf86..cb28e05 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -43,6 +43,7 @@ int acpi_power_transition(struct acpi_device *device, int state); > extern int acpi_power_nocheck; > > int acpi_wakeup_device_init(void); > +void acpi_early_processor_set_pdc(void); > > /* -------------------------------------------------------------------------- > Embedded Controller > diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c > index 4173123..a19a4ff 100644 > --- a/drivers/acpi/processor_core.c > +++ b/drivers/acpi/processor_core.c > @@ -124,29 +124,6 @@ static const struct file_operations acpi_processor_info_fops = { > > DEFINE_PER_CPU(struct acpi_processor *, processors); > struct acpi_processor_errata errata __read_mostly; > -static int set_no_mwait(const struct dmi_system_id *id) > -{ > - printk(KERN_NOTICE PREFIX "%s detected - " > - "disabling mwait for CPU C-states\n", id->ident); > - idle_nomwait = 1; > - return 0; > -} > - > -static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = { > - { > - set_no_mwait, "IFL91 board", { > - DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"), > - DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"), > - DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"), > - DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL}, > - { > - set_no_mwait, "Extensa 5220", { > - DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"), > - DMI_MATCH(DMI_SYS_VENDOR, "Acer"), > - DMI_MATCH(DMI_PRODUCT_VERSION, "0100"), > - DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL}, > - {}, > -}; > > /* -------------------------------------------------------------------------- > Errata Handling > @@ -277,45 +254,6 @@ static int acpi_processor_errata(struct acpi_processor *pr) > } > > /* -------------------------------------------------------------------------- > - Common ACPI processor functions > - -------------------------------------------------------------------------- */ > - > -/* > - * _PDC is required for a BIOS-OS handshake for most of the newer > - * ACPI processor features. > - */ > -static int acpi_processor_set_pdc(struct acpi_processor *pr) > -{ > - struct acpi_object_list *pdc_in = pr->pdc; > - acpi_status status = AE_OK; > - > - > - if (!pdc_in) > - return status; > - if (idle_nomwait) { > - /* > - * If mwait is disabled for CPU C-states, the C2C3_FFH access > - * mode will be disabled in the parameter of _PDC object. > - * Of course C1_FFH access mode will also be disabled. > - */ > - union acpi_object *obj; > - u32 *buffer = NULL; > - > - obj = pdc_in->pointer; > - buffer = (u32 *)(obj->buffer.pointer); > - buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH); > - > - } > - status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL); > - > - if (ACPI_FAILURE(status)) > - ACPI_DEBUG_PRINT((ACPI_DB_INFO, > - "Could not evaluate _PDC, using legacy perf. control...\n")); > - > - return status; > -} > - > -/* -------------------------------------------------------------------------- > FS Interface (/proc) > -------------------------------------------------------------------------- */ > > @@ -825,9 +763,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device) > } > > /* _PDC call should be done before doing anything else (if reqd.). */ > - arch_acpi_processor_init_pdc(pr); > acpi_processor_set_pdc(pr); > - arch_acpi_processor_cleanup_pdc(pr); > > #ifdef CONFIG_CPU_FREQ > acpi_processor_ppc_has_changed(pr, 0); > @@ -1145,11 +1081,6 @@ static int __init acpi_processor_init(void) > if (!acpi_processor_dir) > return -ENOMEM; > #endif > - /* > - * Check whether the system is DMI table. If yes, OSPM > - * should not use mwait for CPU-states. > - */ > - dmi_check_system(processor_idle_dmi_table); > result = cpuidle_register_driver(&acpi_idle_driver); > if (result < 0) > goto out_proc; > diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c > new file mode 100644 > index 0000000..b416c32 > --- /dev/null > +++ b/drivers/acpi/processor_pdc.c > @@ -0,0 +1,108 @@ > +#include <linux/dmi.h> > + > +#include <acpi/acpi_drivers.h> > +#include <acpi/processor.h> > + > +#include "internal.h" > + > +#define PREFIX "ACPI: " > +#define _COMPONENT ACPI_PROCESSOR_COMPONENT > +ACPI_MODULE_NAME("processor_pdc"); > + > +static int set_no_mwait(const struct dmi_system_id *id) > +{ > + printk(KERN_NOTICE PREFIX "%s detected - " > + "disabling mwait for CPU C-states\n", id->ident); > + idle_nomwait = 1; > + return 0; > +} > + > +static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = { > + { > + set_no_mwait, "IFL91 board", { > + DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"), > + DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"), > + DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"), > + DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL}, > + { > + set_no_mwait, "Extensa 5220", { > + DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"), > + DMI_MATCH(DMI_SYS_VENDOR, "Acer"), > + DMI_MATCH(DMI_PRODUCT_VERSION, "0100"), > + DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL}, > + {}, > +}; > + > +/* > + * _PDC is required for a BIOS-OS handshake for most of the newer > + * ACPI processor features. > + */ > +static int acpi_processor_eval_pdc(struct acpi_processor *pr) > +{ > + struct acpi_object_list *pdc_in = pr->pdc; > + acpi_status status = AE_OK; > + > + if (!pdc_in) > + return status; > + if (idle_nomwait) { > + /* > + * If mwait is disabled for CPU C-states, the C2C3_FFH access > + * mode will be disabled in the parameter of _PDC object. > + * Of course C1_FFH access mode will also be disabled. > + */ > + union acpi_object *obj; > + u32 *buffer = NULL; > + > + obj = pdc_in->pointer; > + buffer = (u32 *)(obj->buffer.pointer); > + buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH); > + > + } > + status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL); > + > + if (ACPI_FAILURE(status)) > + ACPI_DEBUG_PRINT((ACPI_DB_INFO, > + "Could not evaluate _PDC, using legacy perf. control.\n")); > + > + return status; > +} > + > +void acpi_processor_set_pdc(struct acpi_processor *pr) > +{ > + arch_acpi_processor_init_pdc(pr); > + acpi_processor_eval_pdc(pr); > + arch_acpi_processor_cleanup_pdc(pr); > +} > +EXPORT_SYMBOL_GPL(acpi_processor_set_pdc); > + > +static acpi_status > +early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv) > +{ > + struct acpi_processor pr; > + > + pr.handle = handle; > + > + /* x86 implementation looks at pr.id to determine some > + * CPU capabilites. We can just hard code to 0 since we're > + * assuming the CPUs in the system are homogenous and all > + * have the same capabilities. > + */ > + pr.id = 0; > + > + acpi_processor_set_pdc(&pr); > + > + return AE_OK; > +} > + > +void acpi_early_processor_set_pdc(void) > +{ > + /* > + * Check whether the system is DMI table. If yes, OSPM > + * should not use mwait for CPU-states. > + */ > + dmi_check_system(processor_idle_dmi_table); > + > + acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, > + ACPI_UINT32_MAX, > + early_init_pdc, NULL, NULL, NULL); > +} > diff --git a/include/acpi/processor.h b/include/acpi/processor.h > index 29245c6..a1b748a 100644 > --- a/include/acpi/processor.h > +++ b/include/acpi/processor.h > @@ -325,6 +325,9 @@ static inline int acpi_processor_get_bios_limit(int cpu, unsigned int *limit) > > #endif /* CONFIG_CPU_FREQ */ > > +/* in processor_pdc.c */ > +void acpi_processor_set_pdc(struct acpi_processor *pr); > + > /* in processor_throttling.c */ > int acpi_processor_tstate_has_changed(struct acpi_processor *pr); > int acpi_processor_get_throttling_info(struct acpi_processor *pr); > -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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