This patch implements a generic modalias 'cpu:feature:...' which enables CPU feature flag based module loading in a generic way. All the arch needs to do is enable CONFIG_ARCH_HAS_CPU_AUTOPROBE and export a u32 called 'cpu_features'. (What each bit actually means is irrelevant on this level.)
Signed-off-by: Ard Biesheuvel <[email protected]> --- drivers/base/cpu.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 49c6f4b..a661d31 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -276,6 +276,30 @@ static void cpu_device_release(struct device *dev) } #ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE +ssize_t print_cpu_modalias(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + extern u32 __weak cpu_features; + ssize_t n; + int i; + u32 f; + + /* + * With 32 features maximum (taking 3 bytes each to print), we don't + * need to worry about overrunning the PAGE_SIZE sized buffer. + */ + n = sprintf(buf, "cpu:feature:"); + for (f = cpu_features, i = 0; f; f >>= 1, i++) + if (f & 1) + n += sprintf(&buf[n], ",%02X", i); + buf[n++] = '\n'; + return n; +} + +ssize_t __attribute__((weak, alias("print_cpu_modalias"))) +arch_print_cpu_modalias(struct device *, struct device_attribute *, char *); + static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env) { char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
