[CPUFREQ] Acer Aspire's have broken PST tables in one BIOS rev. DMI blacklist it.

arch/i386/kernel/cpu/cpufreq/powernow-k7.c

@@ -390,6 +390,10 @@ static struct cpufreq_driver powernow_driver = {
 
 static int __init powernow_init (void)
 {
+	if (dmi_broken & BROKEN_CPUFREQ) {
+		printk (KERN_INFO PFX "Disabled at boot time by DMI,\n");
+		return -ENODEV;
+	}
 	if (check_powernow()==0)
 		return -ENODEV;
 	return cpufreq_register_driver(&powernow_driver);

arch/i386/kernel/dmi_scan.c

@@ -511,6 +511,14 @@ static __init int exploding_pnp_bios(struct dmi_blacklist *d)
 	return 0;
 }
 
+static __init int acer_cpufreq_pst(struct dmi_blacklist *d)
+{
+	printk(KERN_WARNING "%s laptop with broken PST tables in BIOS detected.\n", d->ident);
+	printk(KERN_WARNING "You need to downgrade to 3A21 (09/09/2002), or try a newer BIOS than 3A71 (01/20/2003)\n");
+	printk(KERN_WARNING "cpufreq scaling has been disabled as a result of this.\n");
+	dmi_broken |= BROKEN_CPUFREQ;
+	return 0;
+}
 
 
 /*
@@ -825,6 +833,17 @@ static __initdata struct dmi_blacklist dmi_blacklist[]={
 			NO_MATCH, NO_MATCH, NO_MATCH
 			} },
 
+	/*
+	 * Some Athlon laptops have really fucked PST tables.
+	 * A BIOS update is all that can save them.
+	 * Mention this, and disable cpufreq.
+	 */
+	{ acer_cpufreq_pst, "Acer Aspire", {
+			MATCH(DMI_SYS_VENDOR, "Insyde Software"),
+			MATCH(DMI_BIOS_VERSION, "3A71"),
+			NO_MATCH, NO_MATCH, NO_MATCH
+			} },
+
 	{ NULL, }
 };
 	

include/asm-i386/system.h

@@ -444,5 +444,6 @@ extern int is_sony_vaio_laptop;
 #define BROKEN_ACPI_Sx		0x0001
 #define BROKEN_INIT_AFTER_S1	0x0002
 #define BROKEN_PNP_BIOS		0x0004
+#define BROKEN_CPUFREQ		0x0008
 
 #endif