Parse CPUID(0x4) and CPUID(0x8000001d).

Query CPUID(0x4) only for Intel, Centaur, and Zhaoxin as these are the x86
vendors where it is supported.  Query CPUID(0x8000001d) for AMD and Hygon.

Define a single CPUID parser read function for both leaves, as they have
the same subleaf cache enumeration logic.

Introduce the macro

    define_cpuid_read_function()

to avoid code duplication between the CPUID parser default read function,
cpuid_read_generic(), and the new CPUID(0x4)/CPUID(0x8000001d) logic.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
---
 arch/x86/include/asm/cpuid/types.h |  2 ++
 arch/x86/kernel/cpu/cpuid_parser.c | 40 +++++++++++++++++++++++-------
 arch/x86/kernel/cpu/cpuid_parser.h |  4 +++
 3 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/cpuid/types.h b/arch/x86/include/asm/cpuid/types.h
index c35de721f652..f77659303569 100644
--- a/arch/x86/include/asm/cpuid/types.h
+++ b/arch/x86/include/asm/cpuid/types.h
@@ -211,11 +211,13 @@ struct cpuid_leaves {
 	CPUID_LEAF   (	0x0,		0  );
 	CPUID_LEAF   (	0x1,		0  );
 	CPUID_LEAF   (  0x2,		0  );
+	CPUID_LEAF_N (  0x4,		8  );
 	CPUID_LEAF   (	0x16,		0  );
 	CPUID_LEAF   (  0x80000000,	0  );
 	CPUID_LEAF   (  0x80000002,	0  );
 	CPUID_LEAF   (  0x80000003,	0  );
 	CPUID_LEAF   (  0x80000004,	0  );
+	CPUID_LEAF_N (  0x8000001d,	8  );
 	CPUID_LEAF   (  0x80860000,	0  );
 	CPUID_LEAF   (  0x80860001,	0  );
 	CPUID_LEAF   (  0x80860002,	0  );
diff --git a/arch/x86/kernel/cpu/cpuid_parser.c b/arch/x86/kernel/cpu/cpuid_parser.c
index bddd9937bb2b..99507e99d8d9 100644
--- a/arch/x86/kernel/cpu/cpuid_parser.c
+++ b/arch/x86/kernel/cpu/cpuid_parser.c
@@ -31,18 +31,34 @@ static const struct cpuid_vendor_entry cpuid_vendor_entries[] = {
  * Leaf read functions:
  */
 
+/**
+ * define_cpuid_read_function() - Generate a CPUID parser read function
+ * @suffix:	Generated function name suffix (full name becomes: cpuid_read_@suffix())
+ * @_leaf_t:	Type to cast the CPUID output storage pointer
+ * @_leaf:	Name of the CPUID output storage pointer
+ * @_break_c:	Condition to break the CPUID parsing loop, which may reference @_leaf,
+ *		and where @_leaf stores each iteration's CPUID output.
+ *
+ * Define a CPUID parser read function according to the requirements stated at
+ * 'struct cpuid_parse_entry'->read().
+ */
+#define define_cpuid_read_function(suffix, _leaf_t, _leaf, _break_c)				\
+static void											\
+cpuid_read_##suffix(const struct cpuid_parse_entry *e, const struct cpuid_read_output *output)	\
+{												\
+	struct _leaf_t *_leaf = (struct _leaf_t *)output->regs;					\
+												\
+	for (int i = 0; i < e->maxcnt; i++, _leaf++, output->info->nr_entries++) {		\
+		cpuid_read_subleaf(e->leaf, e->subleaf + i, _leaf);				\
+		if (_break_c)									\
+			break;									\
+	}											\
+}
+
 /*
  * Default CPUID read function
- * Satisfies the requirements stated at 'struct cpuid_parse_entry'->read().
  */
-static void
-cpuid_read_generic(const struct cpuid_parse_entry *e, const struct cpuid_read_output *output)
-{
-	struct cpuid_regs *regs = output->regs;
-
-	for (int i = 0; i < e->maxcnt; i++, regs++, output->info->nr_entries++)
-		cpuid_read_subleaf(e->leaf, e->subleaf + i, regs);
-}
+define_cpuid_read_function(generic, cpuid_regs, ignored, false);
 
 static void
 cpuid_read_0x2(const struct cpuid_parse_entry *e, const struct cpuid_read_output *output)
@@ -83,6 +99,12 @@ cpuid_read_0x2(const struct cpuid_parse_entry *e, const struct cpuid_read_output
 	output->info->nr_entries = 1;
 }
 
+/*
+ * Shared read function for Intel CPUID(0x4) and AMD CPUID(0x8000001d), as both have
+ * the same subleaf enumeration logic and register output format.
+ */
+define_cpuid_read_function(deterministic_cache, leaf_0x4_n, l, l->cache_type == 0);
+
 /*
  * Define an extended range CPUID read function
  *
diff --git a/arch/x86/kernel/cpu/cpuid_parser.h b/arch/x86/kernel/cpu/cpuid_parser.h
index 1de239370652..25ca9b19e8cf 100644
--- a/arch/x86/kernel/cpu/cpuid_parser.h
+++ b/arch/x86/kernel/cpu/cpuid_parser.h
@@ -145,11 +145,13 @@ struct cpuid_parse_entry {
 #define CPUID_COMMON_ENTRIES									\
 	/*			Leaf		Subleaf		Reader function */		\
 	CPUID_PARSE_ENTRY   (	0x2,		0,		0x2			),	\
+	CPUID_PARSE_ENTRY_N (	0x4,				deterministic_cache	),	\
 	CPUID_PARSE_ENTRY   (	0x16,		0,		generic			),	\
 	CPUID_PARSE_ENTRY   (	0x80000000,	0,		0x80000000		),	\
 	CPUID_PARSE_ENTRY   (	0x80000002,	0,		generic			),	\
 	CPUID_PARSE_ENTRY   (	0x80000003,	0,		generic			),	\
 	CPUID_PARSE_ENTRY   (	0x80000004,	0,		generic			),	\
+	CPUID_PARSE_ENTRY_N (	0x8000001d,			deterministic_cache	),	\
 	CPUID_PARSE_ENTRY   (	0x80860000,	0,		0x80860000		),	\
 	CPUID_PARSE_ENTRY   (	0x80860001,	0,		generic			),	\
 	CPUID_PARSE_ENTRY   (	0x80860002,	0,		generic			),	\
@@ -192,7 +194,9 @@ struct cpuid_vendor_entry {
 #define CPUID_VENDOR_ENTRIES								\
 	/*		   Leaf		Vendor list		    */			\
 	CPUID_VENDOR_ENTRY(0x2,		X86_VENDOR_INTEL, X86_VENDOR_CENTAUR, X86_VENDOR_ZHAOXIN),\
+	CPUID_VENDOR_ENTRY(0x4,		X86_VENDOR_INTEL, X86_VENDOR_CENTAUR, X86_VENDOR_ZHAOXIN),\
 	CPUID_VENDOR_ENTRY(0x16,	X86_VENDOR_INTEL),				\
+	CPUID_VENDOR_ENTRY(0x8000001d,	X86_VENDOR_AMD, X86_VENDOR_HYGON),		\
 	CPUID_VENDOR_ENTRY(0x80860000,	X86_VENDOR_TRANSMETA),				\
 	CPUID_VENDOR_ENTRY(0x80860001,	X86_VENDOR_TRANSMETA),				\
 	CPUID_VENDOR_ENTRY(0x80860002,	X86_VENDOR_TRANSMETA),				\
-- 
2.53.0