[RFC][PATCH 9/10 -tip] x86: cpu_debug display cpuid functions

[Jaswinder Singh Rajput <jaswinder@kernel.org>]

Add support for cpuid standard and extended functions

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
---
 arch/x86/include/asm/cpu_debug.h |    4 ++-
 arch/x86/kernel/cpu/cpu_debug.c  |   64 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 64 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/cpu_debug.h b/arch/x86/include/asm/cpu_debug.h
index dc24338..377f658 100644
--- a/arch/x86/include/asm/cpu_debug.h
+++ b/arch/x86/include/asm/cpu_debug.h
@@ -46,11 +46,11 @@ enum cpu_debug_bit {
 	CPU_MMIO,				/* Memory based IO	*/
 	CPU_DISPLAY,				/* Display/VGA		*/
 	CPU_LINK,				/* HyperTransport	*/
-	CPU_CPUID,				/* CPUID		*/
 /* Standard Registers							*/
 	CPU_TSS,				/* Task Stack Segment	*/
 	CPU_CR,					/* Control Registers	*/
 	CPU_DT,					/* Descriptor Table	*/
+	CPU_CPUID,				/* CPUID		*/
 	CPU_PCI,				/* PCI configuration	*/
 /* End of Registers flags						*/
 	CPU_REG_MAX,				/* Max Registers flags	*/
@@ -75,6 +75,8 @@ enum cpu_cat_bit {
 #define MAX_CPU_FILES		768		/* Max CPU debug files	*/
 #define MAX_CPU_PCI		5		/* AMD supports func 0-4*/
 
+#define CPUID_MASK		0xffff0000
+
 struct cpu_private {
 	unsigned		cpu;
 	unsigned		type;
diff --git a/arch/x86/kernel/cpu/cpu_debug.c b/arch/x86/kernel/cpu/cpu_debug.c
index b4dfddd..f7f702e 100644
--- a/arch/x86/kernel/cpu/cpu_debug.c
+++ b/arch/x86/kernel/cpu/cpu_debug.c
@@ -72,10 +72,10 @@ static struct cpu_debug_base cpu_base[] = {
 	{ "mmio",	CPU_MMIO,	0	},
 	{ "display",	CPU_DISPLAY,	0	},
 	{ "link",	CPU_LINK,	0	},
-	{ "cpuid",	CPU_CPUID,	0	},
 	{ "tss",	CPU_TSS,	0	},
 	{ "cr",		CPU_CR,		0	},
 	{ "dt",		CPU_DT,		0	},
+	{ "cpuid",	CPU_CPUID,	0	},
 	{ "pci",	CPU_PCI,	0	},
 	{ "registers",	CPU_REG_ALL,	0	},
 };
@@ -303,6 +303,13 @@ static struct cpu_debug_range cpu_amd_pci4[] = {
 	{ 0x1E0,	0x1F0,	CPU_POWER	},
 };
 
+/* Extended CPUID base address			*/
+static u32 cpu_ext_cpuid[] = {
+	0x80000000,		/* Intel, AMD	*/
+	0x80860000,		/* Transmeta	*/
+	0xC0000000,		/* Centaur	*/
+};
+
 /* Check validity of cpu debug flag */
 static int is_typeflag_valid(unsigned cpu, unsigned flag)
 {
@@ -518,6 +525,49 @@ static void print_apic(void *arg)
 #endif
 }
 
+/* Get extended CPUID level */
+static u32 get_extended_cpuid(void)
+{
+	u32 i, level;
+
+	for (i = 0; i < ARRAY_SIZE(cpu_ext_cpuid); i++) {
+		level = cpuid_eax(cpu_ext_cpuid[i]);
+		if ((level & CPUID_MASK) == cpu_ext_cpuid[i])
+			return level;
+	}
+
+	return 0;		/* Not found */
+}
+
+static void print_cpuidabcd(struct seq_file *seq, u32 min, u32 max)
+{
+	u32 i, eax, ebx, ecx, edx;
+
+	for (i = min; i <= max; i++) {
+		cpuid(i, &eax, &ebx, &ecx, &edx);
+		seq_printf(seq, " %08x  %08x  %08x  %08x  %08x\n",
+			   i, eax, ebx, ecx, edx);
+	}
+}
+
+static void print_cpuid(void *arg)
+{
+	struct seq_file *seq = arg;
+	u32 level;
+
+	seq_printf(seq, " CPUID\t:\n");
+	seq_printf(seq, "              eax       ebx       ecx       edx\n");
+
+	/* Standard CPUID functions */
+	level = cpuid_eax(0);
+	print_cpuidabcd(seq, 0, level);
+
+	/* Extended CPUID functions */
+	level = get_extended_cpuid();
+	if (level)
+		print_cpuidabcd(seq, (level & CPUID_MASK), level);
+}
+
 static void print_apicval(void *arg)
 {
 	struct seq_file *seq = arg;
@@ -632,6 +682,14 @@ static int cpu_seq_show(struct seq_file *seq, void *v)
 	case CPU_DT:
 		smp_call_function_single(priv->cpu, print_dt, seq, 1);
 		break;
+	case CPU_CPUID:
+		if (priv->file == CPU_INDEX)
+			smp_call_function_single(priv->cpu, print_cpuid,
+						 seq, 1);
+		else
+			smp_call_function_single(priv->cpu, print_pcival,
+						 seq, 1);
+		break;
 	case CPU_PCI:
 		if (priv->file == CPU_INDEX)
 			smp_call_function_single(priv->cpu, print_pci, seq, 1);
@@ -814,7 +872,7 @@ static int cpu_init_regfiles(unsigned cpu, unsigned int type, unsigned reg,
 	unsigned file;
 	int err = 0;
 
-	for (file = 0; file <  ARRAY_SIZE(cpu_file); file++) {
+	for (file = 0; file < ARRAY_SIZE(cpu_file); file++) {
 		err = cpu_create_file(cpu, type, reg, file, cat, dentry);
 		if (err)
 			return err;
@@ -973,7 +1031,7 @@ static int cpu_init_allreg(unsigned cpu, struct dentry *dentry)
 	unsigned type;
 	int err = 0;
 
-	for (type = 0; type <  ARRAY_SIZE(cpu_base) - 1; type++) {
+	for (type = 0; type < ARRAY_SIZE(cpu_base) - 1; type++) {
 		cpu_dentry = debugfs_create_dir(cpu_base[type].name, dentry);
 		per_cpu(cpu_arr[type].dentry, cpu) = cpu_dentry;
 
-- 
1.6.0.6