[PATCH] Add support for National Semiconductor x86's.

These are mostly Cyrix-alike, but for some quirks we work around.

arch/i386/kernel/setup.c

@@ -99,6 +99,8 @@
 #endif
 #include <linux/highmem.h>
 #include <linux/bootmem.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
 #include <linux/seq_file.h>
 #include <linux/console.h>
 #include <asm/processor.h>
@@ -1244,7 +1246,7 @@ static int __init init_amd(struct cpuinfo_x86 *c)
 }
 
 /*
- * Read Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
+ * Read NSC/Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
  */
 static void __init do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
 {
@@ -1340,6 +1342,7 @@ static void __init check_cx686_slop(struct cpuinfo_x86 *c)
 	}
 }
 
+
 static void __init init_cyrix(struct cpuinfo_x86 *c)
 {
 	unsigned char dir0, dir0_msn, dir0_lsn, dir1 = 0;
@@ -1406,13 +1409,8 @@ static void __init init_cyrix(struct cpuinfo_x86 *c)
 		break;
 
 	case 4: /* MediaGX/GXm */
-		/*
-		 *	Life sometimes gets weiiiiiiiird if we use this
-		 *	on the MediaGX. So we turn it off for now. 
-		 */
-		
 #ifdef CONFIG_PCI
-		/* It isnt really a PCI quirk directly, but the cure is the
+		/* It isn't really a PCI quirk directly, but the cure is the
 		   same. The MediaGX has deep magic SMM stuff that handles the
 		   SB emulation. It thows away the fifo on disable_dma() which
 		   is wrong and ruins the audio. 
@@ -1431,7 +1429,16 @@ static void __init init_cyrix(struct cpuinfo_x86 *c)
 
 		/* GXm supports extended cpuid levels 'ala' AMD */
 		if (c->cpuid_level == 2) {
+			/* Enable Natsemi MMX extensions */
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7) | 1);
+
 			get_model_name(c);  /* get CPU marketing name */
+			/*
+			 *  The 5510/5520 companion chips have a funky PIT
+			 *  that breaks the TSC synchronizing, so turn it off
+			 */
+			if(pci_find_device(PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5510, NULL) ||
+				pci_find_device(PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5520, NULL))
 				clear_bit(X86_FEATURE_TSC, c->x86_capability);
 			return;
 		}
@@ -1439,7 +1446,9 @@ static void __init init_cyrix(struct cpuinfo_x86 *c)
 			Cx86_cb[2] = (dir0_lsn & 1) ? '3' : '4';
 			p = Cx86_cb+2;
 			c->x86_model = (dir1 & 0x20) ? 1 : 2;
+#ifndef CONFIG_CS5520
 			clear_bit(X86_FEATURE_TSC, &c->x86_capability);
+#endif
 		}
 		break;
 
@@ -2207,6 +2216,8 @@ void __init get_cpu_vendor(struct cpuinfo_x86 *c)
 		c->x86_vendor = X86_VENDOR_AMD;
 	else if (!strcmp(v, "CyrixInstead"))
 		c->x86_vendor = X86_VENDOR_CYRIX;
+	else if (!strcmp(v, "Geode by NSC"))
+		c->x86_vendor = X86_VENDOR_NSC;
 	else if (!strcmp(v, "UMC UMC UMC "))
 		c->x86_vendor = X86_VENDOR_UMC;
 	else if (!strcmp(v, "CentaurHauls"))
@@ -2532,24 +2543,6 @@ void __init identify_cpu(struct cpuinfo_x86 *c)
 	 * indicate the features this CPU genuinely supports!
 	 */
 	switch ( c->x86_vendor ) {
-	case X86_VENDOR_UNKNOWN:
-	default:
-		/* Not much we can do here... */
-		/* Check if at least it has cpuid */
-		if (c->cpuid_level == -1)
-		{
-			/* No cpuid. It must be an ancient CPU */
-			if (c->x86 == 4)
-				strcpy(c->x86_model_id, "486");
-			else if (c->x86 == 3)
-				strcpy(c->x86_model_id, "386");
-		}
-		break;
-
-	case X86_VENDOR_CYRIX:
-		init_cyrix(c);
-		break;
-
 	case X86_VENDOR_AMD:
 		init_amd(c);
 		break;
@@ -2558,6 +2551,10 @@ void __init identify_cpu(struct cpuinfo_x86 *c)
 		init_centaur(c);
 		break;
 
+	case X86_VENDOR_CYRIX:
+		init_cyrix(c);
+		break;
+
 	case X86_VENDOR_INTEL:
 		init_intel(c);
 		break;
@@ -2566,13 +2563,32 @@ void __init identify_cpu(struct cpuinfo_x86 *c)
 		c->x86_cache_size = 256; /* A few had 1 MB... */
 		break;
 
-	case X86_VENDOR_TRANSMETA:
-		init_transmeta(c);
+	case X86_VENDOR_NSC:
+        init_cyrix(c);
 		break;
 
 	case X86_VENDOR_RISE:
 		init_rise(c);
 		break;
+
+	case X86_VENDOR_TRANSMETA:
+		init_transmeta(c);
+		break;
+
+	case X86_VENDOR_UNKNOWN:
+	default:
+		/* Not much we can do here... */
+		/* Check if at least it has cpuid */
+		if (c->cpuid_level == -1)
+		{
+			/* No cpuid. It must be an ancient CPU */
+			if (c->x86 == 4)
+				strcpy(c->x86_model_id, "486");
+			else if (c->x86 == 3)
+				strcpy(c->x86_model_id, "386");
+		}
+		break;
+
 	}
 
 	printk(KERN_DEBUG "CPU: After vendor init, caps: %08x %08x %08x %08x\n",
@@ -2650,14 +2666,15 @@ void __init dodgy_tsc(void)
 {
 	get_cpu_vendor(&boot_cpu_data);
 
-	if ( boot_cpu_data.x86_vendor == X86_VENDOR_CYRIX )
+	if (( boot_cpu_data.x86_vendor == X86_VENDOR_CYRIX ) ||
+	    ( boot_cpu_data.x86_vendor == X86_VENDOR_NSC   ))
 		init_cyrix(&boot_cpu_data);
 }
 
 
 /* These need to match <asm/processor.h> */
 static char *cpu_vendor_names[] __initdata = {
-	"Intel", "Cyrix", "AMD", "UMC", "NexGen", "Centaur", "Rise", "Transmeta" };
+	"Intel", "Cyrix", "AMD", "UMC", "NexGen", "Centaur", "Rise", "Transmeta", "NSC" };
 
 
 void __init print_cpu_info(struct cpuinfo_x86 *c)

include/asm-i386/processor.h

@@ -59,6 +59,7 @@ struct cpuinfo_x86 {
 #define X86_VENDOR_CENTAUR 5
 #define X86_VENDOR_RISE 6
 #define X86_VENDOR_TRANSMETA 7
+#define X86_VENDOR_NSC 8
 #define X86_VENDOR_UNKNOWN 0xff
 
 /*
@@ -216,7 +217,7 @@ static inline void clear_in_cr4 (unsigned long mask)
 }
 
 /*
- *      Cyrix CPU configuration register indexes
+ *      NSC/Cyrix CPU configuration register indexes
  */
 #define CX86_CCR0 0xc0
 #define CX86_CCR1 0xc1
@@ -232,7 +233,7 @@ static inline void clear_in_cr4 (unsigned long mask)
 #define CX86_RCR_BASE 0xdc
 
 /*
- *      Cyrix CPU indexed register access macros
+ *      NSC/Cyrix CPU indexed register access macros
  */
 
 #define getCx86(reg) ({ outb((reg), 0x22); inb(0x23); })