diff options
| -rw-r--r-- | drivers/base/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/base/cpu.c | 50 | ||||
| -rw-r--r-- | include/linux/cpufeature.h | 60 | ||||
| -rw-r--r-- | include/linux/mod_devicetable.h | 9 | ||||
| -rw-r--r-- | scripts/mod/devicetable-offsets.c | 3 | ||||
| -rw-r--r-- | scripts/mod/file2alias.c | 10 |
6 files changed, 135 insertions, 5 deletions
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index ec36e77..3f0d373 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -185,6 +185,14 @@ config GENERIC_CPU_DEVICES bool default n +config HAVE_CPU_AUTOPROBE + def_bool ARCH_HAS_CPU_AUTOPROBE + +config GENERIC_CPU_AUTOPROBE + bool + depends on !ARCH_HAS_CPU_AUTOPROBE + select HAVE_CPU_AUTOPROBE + config SOC_BUS bool diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index f48370d..8a38bf8 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -15,6 +15,7 @@ #include <linux/percpu.h> #include <linux/acpi.h> #include <linux/of.h> +#include <linux/cpufeature.h> #include "base.h" @@ -286,6 +287,45 @@ static void cpu_device_release(struct device *dev) */ } +#ifdef CONFIG_HAVE_CPU_AUTOPROBE +#ifdef CONFIG_GENERIC_CPU_AUTOPROBE +static ssize_t print_cpu_modalias(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + ssize_t n; + u32 i; + + n = sprintf(buf, "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:", + CPU_FEATURE_TYPEVAL); + + for (i = 0; i < MAX_CPU_FEATURES; i++) + if (cpu_have_feature(i)) { + if (PAGE_SIZE < n + sizeof(",XXXX\n")) { + WARN(1, "CPU features overflow page\n"); + break; + } + n += sprintf(&buf[n], ",%04X", i); + } + buf[n++] = '\n'; + return n; +} +#else +#define print_cpu_modalias arch_print_cpu_modalias +#endif + +static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (buf) { + print_cpu_modalias(NULL, NULL, buf); + add_uevent_var(env, "MODALIAS=%s", buf); + kfree(buf); + } + return 0; +} +#endif + /* * register_cpu - Setup a sysfs device for a CPU. * @cpu - cpu->hotpluggable field set to 1 will generate a control file in @@ -306,8 +346,8 @@ int register_cpu(struct cpu *cpu, int num) cpu->dev.offline_disabled = !cpu->hotpluggable; cpu->dev.offline = !cpu_online(num); cpu->dev.of_node = of_get_cpu_node(num, NULL); -#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE - cpu->dev.bus->uevent = arch_cpu_uevent; +#ifdef CONFIG_HAVE_CPU_AUTOPROBE + cpu->dev.bus->uevent = cpu_uevent; #endif cpu->dev.groups = common_cpu_attr_groups; if (cpu->hotpluggable) @@ -330,8 +370,8 @@ struct device *get_cpu_device(unsigned cpu) } EXPORT_SYMBOL_GPL(get_cpu_device); -#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE -static DEVICE_ATTR(modalias, 0444, arch_print_cpu_modalias, NULL); +#ifdef CONFIG_HAVE_CPU_AUTOPROBE +static DEVICE_ATTR(modalias, 0444, print_cpu_modalias, NULL); #endif static struct attribute *cpu_root_attrs[] = { @@ -344,7 +384,7 @@ static struct attribute *cpu_root_attrs[] = { &cpu_attrs[2].attr.attr, &dev_attr_kernel_max.attr, &dev_attr_offline.attr, -#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE +#ifdef CONFIG_HAVE_CPU_AUTOPROBE &dev_attr_modalias.attr, #endif NULL diff --git a/include/linux/cpufeature.h b/include/linux/cpufeature.h new file mode 100644 index 0000000..c4d4eb8 --- /dev/null +++ b/include/linux/cpufeature.h @@ -0,0 +1,60 @@ +/* + * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef __LINUX_CPUFEATURE_H +#define __LINUX_CPUFEATURE_H + +#ifdef CONFIG_GENERIC_CPU_AUTOPROBE + +#include <linux/mod_devicetable.h> +#include <asm/cpufeature.h> + +/* + * Macros imported from <asm/cpufeature.h>: + * - cpu_feature(x) ordinal value of feature called 'x' + * - cpu_have_feature(u32 n) whether feature #n is available + * - MAX_CPU_FEATURES upper bound for feature ordinal values + * Optional: + * - CPU_FEATURE_TYPEFMT format string fragment for printing the cpu type + * - CPU_FEATURE_TYPEVAL set of values matching the format string above + */ + +#ifndef CPU_FEATURE_TYPEFMT +#define CPU_FEATURE_TYPEFMT "%s" +#endif + +#ifndef CPU_FEATURE_TYPEVAL +#define CPU_FEATURE_TYPEVAL ELF_PLATFORM +#endif + +/* + * Use module_cpu_feature_match(feature, module_init_function) to + * declare that + * a) the module shall be probed upon discovery of CPU feature 'feature' + * (typically at boot time using udev) + * b) the module must not be loaded if CPU feature 'feature' is not present + * (not even by manual insmod). + * + * For a list of legal values for 'feature', please consult the file + * 'asm/cpufeature.h' of your favorite architecture. + */ +#define module_cpu_feature_match(x, __init) \ +static struct cpu_feature const cpu_feature_match_ ## x[] = \ + { { .feature = cpu_feature(x) }, { } }; \ +MODULE_DEVICE_TABLE(cpu, cpu_feature_match_ ## x); \ + \ +static int cpu_feature_match_ ## x ## _init(void) \ +{ \ + if (!cpu_have_feature(cpu_feature(x))) \ + return -ENODEV; \ + return __init(); \ +} \ +module_init(cpu_feature_match_ ## x ## _init) + +#endif +#endif diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index 45e9214..f2ac87c 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -564,6 +564,15 @@ struct x86_cpu_id { #define X86_MODEL_ANY 0 #define X86_FEATURE_ANY 0 /* Same as FPU, you can't test for that */ +/* + * Generic table type for matching CPU features. + * @feature: the bit number of the feature (0 - 65535) + */ + +struct cpu_feature { + __u16 feature; +}; + #define IPACK_ANY_FORMAT 0xff #define IPACK_ANY_ID (~0) struct ipack_device_id { diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c index bb5d115..f282516 100644 --- a/scripts/mod/devicetable-offsets.c +++ b/scripts/mod/devicetable-offsets.c @@ -174,6 +174,9 @@ int main(void) DEVID_FIELD(x86_cpu_id, model); DEVID_FIELD(x86_cpu_id, vendor); + DEVID(cpu_feature); + DEVID_FIELD(cpu_feature, feature); + DEVID(mei_cl_device_id); DEVID_FIELD(mei_cl_device_id, name); diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 25e5cb0..506146e 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1135,6 +1135,16 @@ static int do_x86cpu_entry(const char *filename, void *symval, } ADD_TO_DEVTABLE("x86cpu", x86_cpu_id, do_x86cpu_entry); +/* LOOKS like cpu:type:*:feature:*FEAT* */ +static int do_cpu_entry(const char *filename, void *symval, char *alias) +{ + DEF_FIELD(symval, cpu_feature, feature); + + sprintf(alias, "cpu:type:*:feature:*%04X*", feature); + return 1; +} +ADD_TO_DEVTABLE("cpu", cpu_feature, do_cpu_entry); + /* Looks like: mei:S */ static int do_mei_entry(const char *filename, void *symval, char *alias) |
