From 67bad2fdb754dbef14596c0b5d28b3a12c8dfe84 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sat, 8 Feb 2014 13:34:09 +0100 Subject: cpu: add generic support for CPU feature based module autoloading This patch adds support for advertising optional CPU features over udev using the modalias, and for declaring compatibility with/dependency upon such a feature in a module. The mapping between feature numbers and actual features should be provided by the architecture in a file called which exports the following functions/macros: - cpu_feature(FEAT), a preprocessor macro that maps token FEAT to a numeric index; - bool cpu_have_feature(n), returning whether this CPU has support for feature #n; - MAX_CPU_FEATURES, an upper bound for 'n' in the previous function. The feature can then be enabled by setting CONFIG_GENERIC_CPU_AUTOPROBE for the architecture. For instance, a module that registers its module init function using module_cpu_feature_match(FEAT_X, module_init_function) will be probed automatically when the CPU's support for the 'FEAT_X' feature is advertised over udev, and will only allow the module to be loaded by hand if the 'FEAT_X' feature is supported. Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- scripts/mod/devicetable-offsets.c | 3 +++ scripts/mod/file2alias.c | 10 ++++++++++ 2 files changed, 13 insertions(+) (limited to 'scripts/mod') diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c index bb5d115ca671..f282516acc7b 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 25e5cb0aaef6..506146e5f4a8 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) -- cgit v1.2.1 From 2b9c1f03278ab7cd421f14ce24dee39091ecb064 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sat, 8 Feb 2014 13:34:10 +0100 Subject: x86: align x86 arch with generic CPU modalias handling The x86 CPU feature modalias handling existed before it was reimplemented generically. This patch aligns the x86 handling so that it (a) reuses some more code that is now generic; (b) uses the generic format for the modalias module metadata entry, i.e., it now uses 'cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:,XXXX,YYYY' instead of the 'x86cpu:vendor:VVVV:family:FFFF:model:MMMM:feature:,XXXX,YYYY' that was used before. Signed-off-by: Ard Biesheuvel Acked-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- scripts/mod/file2alias.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 506146e5f4a8..25f6f5970552 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1110,7 +1110,7 @@ static int do_amba_entry(const char *filename, } ADD_TO_DEVTABLE("amba", amba_id, do_amba_entry); -/* LOOKS like x86cpu:vendor:VVVV:family:FFFF:model:MMMM:feature:*,FEAT,* +/* LOOKS like cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:*,FEAT,* * All fields are numbers. It would be nicer to use strings for vendor * and feature, but getting those out of the build system here is too * complicated. @@ -1124,10 +1124,10 @@ static int do_x86cpu_entry(const char *filename, void *symval, DEF_FIELD(symval, x86_cpu_id, model); DEF_FIELD(symval, x86_cpu_id, vendor); - strcpy(alias, "x86cpu:"); - ADD(alias, "vendor:", vendor != X86_VENDOR_ANY, vendor); - ADD(alias, ":family:", family != X86_FAMILY_ANY, family); - ADD(alias, ":model:", model != X86_MODEL_ANY, model); + strcpy(alias, "cpu:type:x86,"); + ADD(alias, "ven", vendor != X86_VENDOR_ANY, vendor); + ADD(alias, "fam", family != X86_FAMILY_ANY, family); + ADD(alias, "mod", model != X86_MODEL_ANY, model); strcat(alias, ":feature:*"); if (feature != X86_FEATURE_ANY) sprintf(alias + strlen(alias), "%04X*", feature); -- cgit v1.2.1