[RFC 01/10] x86/microcode/intel: expose collect_cpu_info_early() for IFS

Jithu Joseph
2022-03-01T19:55:57Z

IFS uses a image provided by Intel that can be regarded as firmware.
IFS image carries the Processor Signature such as family/model/stepping
similar to what we find in the microcode header.

Expose collect_cpu_info_early() and cpu_signatures_match() for IFS image
sanity check.

No functional change.

Originally-by: Kyung Min Park <kyung.min.park@intel.com>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
---
arch/x86/include/asm/microcode_intel.h | 6 ++++++
arch/x86/kernel/cpu/microcode/intel.c | 8 +++++---
2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/microcode_intel.h b/arch/x86/include/asm/microcode_intel.h
index d85a07d7154f..ec19eeac535b 100644
--- a/arch/x86/include/asm/microcode_intel.h
+++ b/arch/x86/include/asm/microcode_intel.h
@@ -74,12 +74,18 @@ extern void load_ucode_intel_ap(void);
extern void show_ucode_info_early(void);
extern int __init save_microcode_in_initrd_intel(void);
void reload_ucode_intel(void);
+int collect_cpu_info_early(struct ucode_cpu_info *uci);
+bool cpu_signatures_match(unsigned int s1, unsigned int p1,
+ unsigned int s2, unsigned int p2);
#else
static inline __init void load_ucode_intel_bsp(void) {}
static inline void load_ucode_intel_ap(void) {}
static inline void show_ucode_info_early(void) {}
static inline int __init save_microcode_in_initrd_intel(void) { return -EINVAL; }
static inline void reload_ucode_intel(void) {}
+static inline void collect_cpu_info_early(struct ucode_cpu_info *uci) {}
+static inline void cpu_signatures_match(unsigned int s1, unsigned int p1,
+ unsigned int s2, unsigned int p2) {}
#endif

#endif /* _ASM_X86_MICROCODE_INTEL_H */
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index d28a9f8f3fec..360ec06eec1e 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -45,8 +45,8 @@ static struct microcode_intel *intel_ucode_patch;
/* last level cache size per core */
static int llc_size_per_core;

-static inline bool cpu_signatures_match(unsigned int s1, unsigned int p1,
- unsigned int s2, unsigned int p2)
+bool cpu_signatures_match(unsigned int s1, unsigned int p1,
+ unsigned int s2, unsigned int p2)
{
if (s1 != s2)
return false;
@@ -58,6 +58,7 @@ static inline bool cpu_signatures_match(unsigned int s1, unsigned int p1,
/* ... or they intersect. */
return p1 & p2;
}
+EXPORT_SYMBOL_GPL(cpu_signatures_match);

/*
* Returns 1 if update has been found, 0 otherwise.
@@ -342,7 +343,7 @@ scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save)
return patch;
}

-static int collect_cpu_info_early(struct ucode_cpu_info *uci)
+int collect_cpu_info_early(struct ucode_cpu_info *uci)
{
unsigned int val[2];
unsigned int family, model;
@@ -372,6 +373,7 @@ static int collect_cpu_info_early(struct ucode_cpu_info *uci)

return 0;
}
+EXPORT_SYMBOL_GPL(collect_cpu_info_early);

static void show_saved_mc(void)
{
--
2.17.1