[PATCH 08/13] x86/microcode: Consolidate family,model, ... code

[Borislav Petkov]

From: Borislav Petkov <bp@xxxxxxx>

... to the header. Split the family acquiring function into a
main one, doing CPUID and a helper which computes the extended
family and is used in multiple places. Get rid of the locally-grown
get_x86_{family,model}().

While at it, rename local variables to something more descriptive and
vertically align assignments for better readability.

There should be no functionality change resulting from this patch.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
 arch/x86/include/asm/microcode.h            | 73 ++++++++++++++++++++++++++++
 arch/x86/kernel/cpu/microcode/core_early.c  | 75 +++++------------------------
 arch/x86/kernel/cpu/microcode/intel_early.c | 59 ++++++-----------------
 3 files changed, 101 insertions(+), 106 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 201b520521ed..2fb20d6f7e23 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -75,6 +75,79 @@ static inline void __exit exit_amd_microcode(void) {}
 
 #ifdef CONFIG_MICROCODE_EARLY
 #define MAX_UCODE_COUNT 128
+
+#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
+#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
+#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
+#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
+#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
+#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
+#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
+
+#define CPUID_IS(a, b, c, ebx, ecx, edx)	\
+		(!((ebx ^ (a))|(edx ^ (b))|(ecx ^ (c))))
+
+/*
+ * In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
+ * x86_vendor() gets vendor id for BSP.
+ *
+ * In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
+ * coding, we still use x86_vendor() to get vendor id for AP.
+ *
+ * x86_vendor() gets vendor information directly from CPUID.
+ */
+static inline int x86_vendor(void)
+{
+	u32 eax = 0x00000000;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
+		return X86_VENDOR_INTEL;
+
+	if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
+		return X86_VENDOR_AMD;
+
+	return X86_VENDOR_UNKNOWN;
+}
+
+static inline unsigned int __x86_family(unsigned int sig)
+{
+	unsigned int x86;
+
+	x86 = (sig >> 8) & 0xf;
+
+	if (x86 == 0xf)
+		x86 += (sig >> 20) & 0xff;
+
+	return x86;
+}
+
+static inline unsigned int x86_family(void)
+{
+	u32 eax = 0x00000001;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	return __x86_family(eax);
+}
+
+static inline unsigned int x86_model(unsigned int sig)
+{
+	unsigned int x86, model;
+
+	x86 = __x86_family(sig);
+
+	model = (sig >> 4) & 0xf;
+
+	if (x86 == 0x6 || x86 == 0xf)
+		model += ((sig >> 16) & 0xf) << 4;
+
+	return model;
+}
+
 extern void __init load_ucode_bsp(void);
 extern void load_ucode_ap(void);
 extern int __init save_microcode_in_initrd(void);
diff --git a/arch/x86/kernel/cpu/microcode/core_early.c b/arch/x86/kernel/cpu/microcode/core_early.c
index d45df4bd16ab..a413a69cbd74 100644
--- a/arch/x86/kernel/cpu/microcode/core_early.c
+++ b/arch/x86/kernel/cpu/microcode/core_early.c
@@ -23,57 +23,6 @@
 #include <asm/processor.h>
 #include <asm/cmdline.h>
 
-#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
-#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
-#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
-#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
-#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
-#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
-#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
-
-#define CPUID_IS(a, b, c, ebx, ecx, edx)	\
-		(!((ebx ^ (a))|(edx ^ (b))|(ecx ^ (c))))
-
-/*
- * In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
- * x86_vendor() gets vendor id for BSP.
- *
- * In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
- * coding, we still use x86_vendor() to get vendor id for AP.
- *
- * x86_vendor() gets vendor information directly through cpuid.
- */
-static int x86_vendor(void)
-{
-	u32 eax = 0x00000000;
-	u32 ebx, ecx = 0, edx;
-
-	native_cpuid(&eax, &ebx, &ecx, &edx);
-
-	if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
-		return X86_VENDOR_INTEL;
-
-	if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
-		return X86_VENDOR_AMD;
-
-	return X86_VENDOR_UNKNOWN;
-}
-
-static int x86_family(void)
-{
-	u32 eax = 0x00000001;
-	u32 ebx, ecx = 0, edx;
-	int x86;
-
-	native_cpuid(&eax, &ebx, &ecx, &edx);
-
-	x86 = (eax >> 8) & 0xf;
-	if (x86 == 15)
-		x86 += (eax >> 20) & 0xff;
-
-	return x86;
-}
-
 static bool __init check_loader_disabled_bsp(void)
 {
 #ifdef CONFIG_X86_32
@@ -96,7 +45,7 @@ static bool __init check_loader_disabled_bsp(void)
 
 void __init load_ucode_bsp(void)
 {
-	int vendor, x86;
+	int vendor, family;
 
 	if (check_loader_disabled_bsp())
 		return;
@@ -105,15 +54,15 @@ void __init load_ucode_bsp(void)
 		return;
 
 	vendor = x86_vendor();
-	x86 = x86_family();
+	family = x86_family();
 
 	switch (vendor) {
 	case X86_VENDOR_INTEL:
-		if (x86 >= 6)
+		if (family >= 6)
 			load_ucode_intel_bsp();
 		break;
 	case X86_VENDOR_AMD:
-		if (x86 >= 0x10)
+		if (family >= 0x10)
 			load_ucode_amd_bsp();
 		break;
 	default:
@@ -132,7 +81,7 @@ static bool check_loader_disabled_ap(void)
 
 void load_ucode_ap(void)
 {
-	int vendor, x86;
+	int vendor, family;
 
 	if (check_loader_disabled_ap())
 		return;
@@ -141,15 +90,15 @@ void load_ucode_ap(void)
 		return;
 
 	vendor = x86_vendor();
-	x86 = x86_family();
+	family = x86_family();
 
 	switch (vendor) {
 	case X86_VENDOR_INTEL:
-		if (x86 >= 6)
+		if (family >= 6)
 			load_ucode_intel_ap();
 		break;
 	case X86_VENDOR_AMD:
-		if (x86 >= 0x10)
+		if (family >= 0x10)
 			load_ucode_amd_ap();
 		break;
 	default:
@@ -179,18 +128,18 @@ int __init save_microcode_in_initrd(void)
 
 void reload_early_microcode(void)
 {
-	int vendor, x86;
+	int vendor, family;
 
 	vendor = x86_vendor();
-	x86 = x86_family();
+	family = x86_family();
 
 	switch (vendor) {
 	case X86_VENDOR_INTEL:
-		if (x86 >= 6)
+		if (family >= 6)
 			reload_ucode_intel();
 		break;
 	case X86_VENDOR_AMD:
-		if (x86 >= 0x10)
+		if (family >= 0x10)
 			reload_ucode_amd();
 		break;
 	default:
diff --git a/arch/x86/kernel/cpu/microcode/intel_early.c b/arch/x86/kernel/cpu/microcode/intel_early.c
index 372ffc7d929b..c3892244fe3e 100644
--- a/arch/x86/kernel/cpu/microcode/intel_early.c
+++ b/arch/x86/kernel/cpu/microcode/intel_early.c
@@ -126,31 +126,6 @@ load_microcode(struct mc_saved_data *mc_saved_data,
 	}
 }
 
-static u8 get_x86_family(unsigned long sig)
-{
-	u8 x86;
-
-	x86 = (sig >> 8) & 0xf;
-
-	if (x86 == 0xf)
-		x86 += (sig >> 20) & 0xff;
-
-	return x86;
-}
-
-static u8 get_x86_model(unsigned long sig)
-{
-	u8 x86, x86_model;
-
-	x86 = get_x86_family(sig);
-	x86_model = (sig >> 4) & 0xf;
-
-	if (x86 == 0x6 || x86 == 0xf)
-		x86_model += ((sig >> 16) & 0xf) << 4;
-
-	return x86_model;
-}
-
 /*
  * Given CPU signature and a microcode patch, this function finds if the
  * microcode patch has matching family and model with the CPU.
@@ -159,42 +134,40 @@ static enum ucode_state
 matching_model_microcode(struct microcode_header_intel *mc_header,
 			unsigned long sig)
 {
-	u8 x86, x86_model;
-	u8 x86_ucode, x86_model_ucode;
+	unsigned int fam, model;
+	unsigned int fam_ucode, model_ucode;
 	struct extended_sigtable *ext_header;
 	unsigned long total_size = get_totalsize(mc_header);
 	unsigned long data_size = get_datasize(mc_header);
 	int ext_sigcount, i;
 	struct extended_signature *ext_sig;
 
-	x86 = get_x86_family(sig);
-	x86_model = get_x86_model(sig);
+	fam   = __x86_family(sig);
+	model = x86_model(sig);
 
-	x86_ucode = get_x86_family(mc_header->sig);
-	x86_model_ucode = get_x86_model(mc_header->sig);
+	fam_ucode   = __x86_family(mc_header->sig);
+	model_ucode = x86_model(mc_header->sig);
 
-	if (x86 == x86_ucode && x86_model == x86_model_ucode)
+	if (fam == fam_ucode && model == model_ucode)
 		return UCODE_OK;
 
 	/* Look for ext. headers: */
 	if (total_size <= data_size + MC_HEADER_SIZE)
 		return UCODE_NFOUND;
 
-	ext_header = (struct extended_sigtable *)
-		     mc_header + data_size + MC_HEADER_SIZE;
+	ext_header   = (struct extended_sigtable *)mc_header + data_size + MC_HEADER_SIZE;
+	ext_sig      = (void *)ext_header + EXT_HEADER_SIZE;
 	ext_sigcount = ext_header->count;
-	ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
 
 	for (i = 0; i < ext_sigcount; i++) {
-		x86_ucode = get_x86_family(ext_sig->sig);
-		x86_model_ucode = get_x86_model(ext_sig->sig);
+		fam_ucode   = __x86_family(ext_sig->sig);
+		model_ucode = x86_model(ext_sig->sig);
 
-		if (x86 == x86_ucode && x86_model == x86_model_ucode)
+		if (fam == fam_ucode && model == model_ucode)
 			return UCODE_OK;
 
 		ext_sig++;
 	}
-
 	return UCODE_NFOUND;
 }
 
@@ -376,7 +349,7 @@ out:
 static int collect_cpu_info_early(struct ucode_cpu_info *uci)
 {
 	unsigned int val[2];
-	u8 x86, x86_model;
+	unsigned int family, model;
 	struct cpu_signature csig;
 	unsigned int eax, ebx, ecx, edx;
 
@@ -391,10 +364,10 @@ static int collect_cpu_info_early(struct ucode_cpu_info *uci)
 	native_cpuid(&eax, &ebx, &ecx, &edx);
 	csig.sig = eax;
 
-	x86 = get_x86_family(csig.sig);
-	x86_model = get_x86_model(csig.sig);
+	family = __x86_family(csig.sig);
+	model  = x86_model(csig.sig);
 
-	if ((x86_model >= 5) || (x86 > 6)) {
+	if ((model >= 5) || (family > 6)) {
 		/* get processor flags from MSR 0x17 */
 		native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
 		csig.pf = 1 << ((val[1] >> 18) & 7);
-- 
2.2.0.33.gc18b867

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