From: Mark Gross mgross@linux.intel.com
commit e9d7144597b10ff13ff2264c059f7d4a7fbc89ac upstream
Intel uses the same family/model for several CPUs. Sometimes the stepping must be checked to tell them apart.
On x86 there can be at most 16 steppings. Add a steppings bitmask to x86_cpu_id and a X86_MATCH_VENDOR_FAMILY_MODEL_STEPPING_FEATURE macro and support for matching against family/model/stepping.
[ bp: Massage. tglx: Lightweight variant for backporting ]
Signed-off-by: Mark Gross mgross@linux.intel.com Signed-off-by: Borislav Petkov bp@suse.de Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Tony Luck tony.luck@intel.com Reviewed-by: Josh Poimboeuf jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/include/asm/cpu_device_id.h | 27 +++++++++++++++++++++++++++ arch/x86/kernel/cpu/match.c | 7 ++++++- include/linux/mod_devicetable.h | 6 ++++++ 3 files changed, 39 insertions(+), 1 deletion(-)
--- a/arch/x86/include/asm/cpu_device_id.h +++ b/arch/x86/include/asm/cpu_device_id.h @@ -9,6 +9,33 @@
#include <linux/mod_devicetable.h>
+#define X86_STEPPINGS(mins, maxs) GENMASK(maxs, mins) + +/** + * X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE - Base macro for CPU matching + * @_vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY + * The name is expanded to X86_VENDOR_@_vendor + * @_family: The family number or X86_FAMILY_ANY + * @_model: The model number, model constant or X86_MODEL_ANY + * @_steppings: Bitmask for steppings, stepping constant or X86_STEPPING_ANY + * @_feature: A X86_FEATURE bit or X86_FEATURE_ANY + * @_data: Driver specific data or NULL. The internal storage + * format is unsigned long. The supplied value, pointer + * etc. is casted to unsigned long internally. + * + * Backport version to keep the SRBDS pile consistant. No shorter variants + * required for this. + */ +#define X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(_vendor, _family, _model, \ + _steppings, _feature, _data) { \ + .vendor = X86_VENDOR_##_vendor, \ + .family = _family, \ + .model = _model, \ + .steppings = _steppings, \ + .feature = _feature, \ + .driver_data = (unsigned long) _data \ +} + extern const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match);
#endif --- a/arch/x86/kernel/cpu/match.c +++ b/arch/x86/kernel/cpu/match.c @@ -34,13 +34,18 @@ const struct x86_cpu_id *x86_match_cpu(c const struct x86_cpu_id *m; struct cpuinfo_x86 *c = &boot_cpu_data;
- for (m = match; m->vendor | m->family | m->model | m->feature; m++) { + for (m = match; + m->vendor | m->family | m->model | m->steppings | m->feature; + m++) { if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor) continue; if (m->family != X86_FAMILY_ANY && c->x86 != m->family) continue; if (m->model != X86_MODEL_ANY && c->x86_model != m->model) continue; + if (m->steppings != X86_STEPPING_ANY && + !(BIT(c->x86_stepping) & m->steppings)) + continue; if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature)) continue; return m; --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -589,6 +589,10 @@ struct mips_cdmm_device_id { /* * MODULE_DEVICE_TABLE expects this struct to be called x86cpu_device_id. * Although gcc seems to ignore this error, clang fails without this define. + * + * Note: The ordering of the struct is different from upstream because the + * static initializers in kernels < 5.7 still use C89 style while upstream + * has been converted to proper C99 initializers. */ #define x86cpu_device_id x86_cpu_id struct x86_cpu_id { @@ -597,6 +601,7 @@ struct x86_cpu_id { __u16 model; __u16 feature; /* bit index */ kernel_ulong_t driver_data; + __u16 steppings; };
#define X86_FEATURE_MATCH(x) \ @@ -605,6 +610,7 @@ struct x86_cpu_id { #define X86_VENDOR_ANY 0xffff #define X86_FAMILY_ANY 0 #define X86_MODEL_ANY 0 +#define X86_STEPPING_ANY 0 #define X86_FEATURE_ANY 0 /* Same as FPU, you can't test for that */
/*