patch-2.4.14 linux/arch/i386/kernel/setup.c

• Lines: 376
• Date: Thu Oct 25 13:53:46 2001
• Orig file: v2.4.13/linux/arch/i386/kernel/setup.c
• Orig date: Tue Oct 23 22:48:49 2001

diff -u --recursive --new-file v2.4.13/linux/arch/i386/kernel/setup.c linux/arch/i386/kernel/setup.c
@@ -229,8 +229,7 @@
 
 #define	SIO_PM_GP_EN	0x80
 
-static void
-visws_get_board_type_and_rev(void)
+static void __init visws_get_board_type_and_rev(void)
 {
 	int raw;
 
@@ -402,7 +401,7 @@
 	}
 }
 
-void __init add_memory_region(unsigned long long start,
+static void __init add_memory_region(unsigned long long start,
                                   unsigned long long size, int type)
 {
 	int x = e820.nr_map;
@@ -667,7 +666,7 @@
  */
 #define LOWMEMSIZE()	(0x9f000)
 
-void __init setup_memory_region(void)
+static void __init setup_memory_region(void)
 {
 	char *who = "BIOS-e820";
 
@@ -699,7 +698,7 @@
 } /* setup_memory_region */
 
 
-static inline void parse_mem_cmdline (char ** cmdline_p)
+static void __init parse_mem_cmdline (char ** cmdline_p)
 {
 	char c = ' ', *to = command_line, *from = COMMAND_LINE;
 	int len = 0;
@@ -1263,11 +1262,11 @@
 /*
  * Read Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
  */
-static void do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+static void __init do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
 {
 	unsigned char ccr2, ccr3;
 	unsigned long flags;
-
+	
 	/* we test for DEVID by checking whether CCR3 is writable */
 	local_irq_save(flags);
 	ccr3 = getCx86(CX86_CCR3);
@@ -1303,7 +1302,7 @@
  * Actually since bugs.h doesnt even reference this perhaps someone should
  * fix the documentation ???
  */
-unsigned char Cx86_dir0_msb __initdata = 0;
+static unsigned char Cx86_dir0_msb __initdata = 0;
 
 static char Cx86_model[][9] __initdata = {
 	"Cx486", "Cx486", "5x86 ", "6x86", "MediaGX ", "6x86MX ",
@@ -1336,7 +1335,7 @@
 static void __init check_cx686_slop(struct cpuinfo_x86 *c)
 {
 	unsigned long flags;
-
+	
 	if (Cx86_dir0_msb == 3) {
 		unsigned char ccr3, ccr5;
 
@@ -1503,6 +1502,248 @@
 	return;
 }
 
+#ifdef CONFIG_X86_OOSTORE
+
+static u32 __init power2(u32 x)
+{
+	u32 s=1;
+	while(s<=x)
+		s<<=1;
+	return s>>=1;
+}
+
+/*
+ *	Set up an actual MCR
+ */
+ 
+static void __init winchip_mcr_insert(int reg, u32 base, u32 size, int key)
+{
+	u32 lo, hi;
+	
+	hi = base & ~0xFFF;
+	lo = ~(size-1);		/* Size is a power of 2 so this makes a mask */
+	lo &= ~0xFFF;		/* Remove the ctrl value bits */
+	lo |= key;		/* Attribute we wish to set */
+	wrmsr(reg+MSR_IDT_MCR0, lo, hi);
+	mtrr_centaur_report_mcr(reg, lo, hi);	/* Tell the mtrr driver */
+}
+
+/*
+ *	Figure what we can cover with MCR's
+ *
+ *	Shortcut: We know you can't put 4Gig of RAM on a winchip
+ */
+
+static u32 __init ramtop(void)		/* 16388 */
+{
+	int i;
+	u32 top = 0;
+	u32 clip = 0xFFFFFFFFUL;
+	
+	for (i = 0; i < e820.nr_map; i++) {
+		unsigned long start, end;
+
+		if (e820.map[i].addr > 0xFFFFFFFFUL)
+			continue;
+		/*
+		 *	Don't MCR over reserved space. Ignore the ISA hole
+		 *	we frob around that catastrophy already
+		 */
+		 			
+		if (e820.map[i].type == E820_RESERVED)
+		{
+			if(e820.map[i].addr >= 0x100000UL && e820.map[i].addr < clip)
+				clip = e820.map[i].addr;
+			continue;
+		}
+		start = e820.map[i].addr;
+		end = e820.map[i].addr + e820.map[i].size;
+		if (start >= end)
+			continue;
+		if (end > top)
+			top = end;
+	}
+	/* Everything below 'top' should be RAM except for the ISA hole.
+	   Because of the limited MCR's we want to map NV/ACPI into our
+	   MCR range for gunk in RAM 
+	   
+	   Clip might cause us to MCR insufficient RAM but that is an
+	   acceptable failure mode and should only bite obscure boxes with
+	   a VESA hole at 15Mb
+	   
+	   The second case Clip sometimes kicks in is when the EBDA is marked
+	   as reserved. Again we fail safe with reasonable results
+	*/
+	
+	if(top>clip)
+		top=clip;
+		
+	return top;
+}
+
+/*
+ *	Compute a set of MCR's to give maximum coverage
+ */
+
+static int __init winchip_mcr_compute(int nr, int key)
+{
+	u32 mem = ramtop();
+	u32 root = power2(mem);
+	u32 base = root;
+	u32 top = root;
+	u32 floor = 0;
+	int ct = 0;
+	
+	while(ct<nr)
+	{
+		u32 fspace = 0;
+
+		/*
+		 *	Find the largest block we will fill going upwards
+		 */
+
+		u32 high = power2(mem-top);	
+
+		/*
+		 *	Find the largest block we will fill going downwards
+		 */
+
+		u32 low = base/2;
+
+		/*
+		 *	Don't fill below 1Mb going downwards as there
+		 *	is an ISA hole in the way.
+		 */		
+		 
+		if(base <= 1024*1024)
+			low = 0;
+			
+		/*
+		 *	See how much space we could cover by filling below
+		 *	the ISA hole
+		 */
+		 
+		if(floor == 0)
+			fspace = 512*1024;
+		else if(floor ==512*1024)
+			fspace = 128*1024;
+
+		/* And forget ROM space */
+		
+		/*
+		 *	Now install the largest coverage we get
+		 */
+		 
+		if(fspace > high && fspace > low)
+		{
+			winchip_mcr_insert(ct, floor, fspace, key);
+			floor += fspace;
+		}
+		else if(high > low)
+		{
+			winchip_mcr_insert(ct, top, high, key);
+			top += high;
+		}
+		else if(low > 0)
+		{
+			base -= low;
+			winchip_mcr_insert(ct, base, low, key);
+		}
+		else break;
+		ct++;
+	}
+	/*
+	 *	We loaded ct values. We now need to set the mask. The caller
+	 *	must do this bit.
+	 */
+	 
+	return ct;
+}
+
+static void __init winchip_create_optimal_mcr(void)
+{
+	int i;
+	/*
+	 *	Allocate up to 6 mcrs to mark as much of ram as possible
+	 *	as write combining and weak write ordered.
+	 *
+	 *	To experiment with: Linux never uses stack operations for 
+	 *	mmio spaces so we could globally enable stack operation wc
+	 *
+	 *	Load the registers with type 31 - full write combining, all
+	 *	writes weakly ordered.
+	 */
+	int used = winchip_mcr_compute(6, 31);
+
+	/*
+	 *	Wipe unused MCRs
+	 */
+	 
+	for(i=used;i<8;i++)
+		wrmsr(MSR_IDT_MCR0+i, 0, 0);
+}
+
+static void __init winchip2_create_optimal_mcr(void)
+{
+	u32 lo, hi;
+	int i;
+
+	/*
+	 *	Allocate up to 6 mcrs to mark as much of ram as possible
+	 *	as write combining, weak store ordered.
+	 *
+	 *	Load the registers with type 25
+	 *		8	-	weak write ordering
+	 *		16	-	weak read ordering
+	 *		1	-	write combining
+	 */
+
+	int used = winchip_mcr_compute(6, 25);
+	
+	/*
+	 *	Mark the registers we are using.
+	 */
+	 
+	rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
+	for(i=0;i<used;i++)
+		lo|=1<<(9+i);
+	wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
+	
+	/*
+	 *	Wipe unused MCRs
+	 */
+	 
+	for(i=used;i<8;i++)
+		wrmsr(MSR_IDT_MCR0+i, 0, 0);
+}
+
+/*
+ *	Handle the MCR key on the Winchip 2.
+ */
+
+static void __init winchip2_unprotect_mcr(void)
+{
+	u32 lo, hi;
+	u32 key;
+	
+	rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
+	lo&=~0x1C0;	/* blank bits 8-6 */
+	key = (lo>>17) & 7;
+	lo |= key<<6;	/* replace with unlock key */
+	wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
+}
+
+static void __init winchip2_protect_mcr(void)
+{
+	u32 lo, hi;
+	
+	rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
+	lo&=~0x1C0;	/* blank bits 8-6 */
+	wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
+}
+	
+#endif
+
 static void __init init_centaur(struct cpuinfo_x86 *c)
 {
 	enum {
@@ -1546,6 +1787,19 @@
 				fcr_clr=DPDC;
 				printk(KERN_NOTICE "Disabling bugged TSC.\n");
 				clear_bit(X86_FEATURE_TSC, &c->x86_capability);
+#ifdef CONFIG_X86_OOSTORE
+				winchip_create_optimal_mcr();
+				/* Enable
+					write combining on non-stack, non-string
+					write combining on string, all types
+					weak write ordering 
+					
+				   The C6 original lacks weak read order 
+				   
+				   Note 0x120 is write only on Winchip 1 */
+				   
+				wrmsr(MSR_IDT_MCR_CTRL, 0x01F0001F, 0);
+#endif				
 				break;
 			case 8:
 				switch(c->x86_mask) {
@@ -1561,11 +1815,37 @@
 				}
 				fcr_set=ECX8|DSMC|DTLOCK|EMMX|EBRPRED|ERETSTK|E2MMX|EAMD3D;
 				fcr_clr=DPDC;
+#ifdef CONFIG_X86_OOSTORE
+				winchip2_unprotect_mcr();
+				winchip2_create_optimal_mcr();
+				rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
+				/* Enable
+					write combining on non-stack, non-string
+					write combining on string, all types
+					weak write ordering 
+				*/
+				lo|=31;				
+				wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
+				winchip2_protect_mcr();
+#endif
 				break;
 			case 9:
 				name="3";
 				fcr_set=ECX8|DSMC|DTLOCK|EMMX|EBRPRED|ERETSTK|E2MMX|EAMD3D;
 				fcr_clr=DPDC;
+#ifdef CONFIG_X86_OOSTORE
+				winchip2_unprotect_mcr();
+				winchip2_create_optimal_mcr();
+				rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
+				/* Enable
+					write combining on non-stack, non-string
+					write combining on string, all types
+					weak write ordering 
+				*/
+				lo|=31;				
+				wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
+				winchip2_protect_mcr();
+#endif
 				break;
 			case 10:
 				name="4";