X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86%2Flib.c;h=3a70c7540db0afa79f1cf42e8dd8ce2392197732;hb=17aac974ab83a3521f2b49b8de33ae05a00fbe07;hp=c499c7a8ed06be6f664f8b39663bc355c1b7fbaa;hpb=83612bb37fbd8e84d90ecb9e6a7157aadd1e2175;p=tpg%2Facess2.git

diff --git a/Kernel/arch/x86/lib.c b/Kernel/arch/x86/lib.c
index c499c7a8..3a70c754 100644
--- a/Kernel/arch/x86/lib.c
+++ b/Kernel/arch/x86/lib.c
@@ -3,17 +3,240 @@
  * lib.c
  */
 #include <acess.h>
+#include <threads_int.h>
+
+#define TRACE_LOCKS	0
+
+#define DEBUG_TO_E9	1
+#define DEBUG_TO_SERIAL	1
+#define	SERIAL_PORT	0x3F8
+#define	GDB_SERIAL_PORT	0x2F8
+
+// === IMPRORTS ===
+#if TRACE_LOCKS
+extern struct sShortSpinlock	glDebug_Lock;
+extern struct sShortSpinlock	glThreadListLock;
+#endif
+extern int	GetCPUNum(void);
+
+// === PROTOTYPES ==
+Uint64	__udivdi3(Uint64 Num, Uint64 Den);
+Uint64	__umoddi3(Uint64 Num, Uint64 Den);
+
+// === GLOBALS ===
+ int	gbDebug_SerialSetup = 0;
+ int	gbGDB_SerialSetup = 0;
 
 // === CODE ===
-void Spinlock(int *lock)
+/**
+ * \brief Determine if a short spinlock is locked
+ * \param Lock	Lock pointer
+ */
+int IS_LOCKED(struct sShortSpinlock *Lock)
+{
+	return !!Lock->Lock;
+}
+
+/**
+ * \brief Check if the current CPU has the lock
+ * \param Lock	Lock pointer
+ */
+int CPU_HAS_LOCK(struct sShortSpinlock *Lock)
+{
+	#if STACKED_LOCKS == 1
+	return Lock->Lock == GetCPUNum() + 1;
+	#elif STACKED_LOCKS == 2
+	return Lock->Lock == Proc_GetCurThread();
+	#else
+	return 0;
+	#endif
+}
+
+/**
+ * \brief Acquire a Short Spinlock
+ * \param Lock	Lock pointer
+ * 
+ * This type of mutex should only be used for very short sections of code,
+ * or in places where a Mutex_* would be overkill, such as appending
+ * an element to linked list (usually two assignement lines in C)
+ * 
+ * \note This type of lock halts interrupts, so ensure that no timing
+ * functions are called while it is held. As a matter of fact, spend as
+ * little time as possible with this lock held
+ * \note If \a STACKED_LOCKS is set, this type of spinlock can be nested
+ */
+void SHORTLOCK(struct sShortSpinlock *Lock)
 {
 	 int	v = 1;
-	while(v)	__asm__ __volatile__ ("lock xchgl %%eax, (%%edi)":"=a"(v):"a"(1),"D"(lock));
+	#if LOCK_DISABLE_INTS
+	 int	IF;
+	#endif
+	#if STACKED_LOCKS == 1
+	 int	cpu = GetCPUNum() + 1;
+	#elif STACKED_LOCKS == 2
+	void	*thread = Proc_GetCurThread();
+	#endif
+	
+	#if LOCK_DISABLE_INTS
+	// Save interrupt state
+	__ASM__ ("pushf;\n\tpop %0" : "=r"(IF));
+	IF &= 0x200;	// AND out all but the interrupt flag
+	#endif
+	
+	#if STACKED_LOCKS == 1
+	if( Lock->Lock == cpu ) {
+		Lock->Depth ++;
+		return ;
+	}
+	#elif STACKED_LOCKS == 2
+	if( Lock->Lock == thread ) {
+		Lock->Depth ++;
+		return ;
+	}
+	#endif
+	
+	#if TRACE_LOCKS
+	if( Lock != &glDebug_Lock && Lock != &glThreadListLock )
+	{
+		//Log_Log("LOCK", "%p locked by %p", Lock, __builtin_return_address(0));
+		Debug("%p obtaining %p (Called by %p)", __builtin_return_address(0), Lock, __builtin_return_address(1));
+	}
+	#endif
+	
+	// Wait for another CPU to release
+	while(v) {
+		// CMPXCHG:
+		//  If r/m32 == EAX, set ZF and set r/m32 = r32
+		//  Else, clear ZF and set EAX = r/m32
+		#if STACKED_LOCKS == 1
+		__ASM__("lock cmpxchgl %2, (%3)"
+			: "=a"(v)
+			: "a"(0), "r"(cpu), "r"(&Lock->Lock)
+			);
+		#elif STACKED_LOCKS == 2
+		__ASM__("lock cmpxchgl %2, (%3)"
+			: "=a"(v)
+			: "a"(0), "r"(thread), "r"(&Lock->Lock)
+			);
+		#else
+		__ASM__("xchgl %%eax, (%%edi)":"=a"(v):"a"(1),"D"(&Lock->Lock));
+		#endif
+		
+		#if LOCK_DISABLE_INTS
+		if( v )	__ASM__("sti");	// Re-enable interrupts
+		#endif
+	}
+	
+	#if LOCK_DISABLE_INTS
+	__ASM__("cli");
+	Lock->IF = IF;
+	#endif
+	
+	#if TRACE_LOCKS
+	if( Lock != &glDebug_Lock && Lock != &glThreadListLock )
+	{
+		//Log_Log("LOCK", "%p locked by %p", Lock, __builtin_return_address(0));
+		//Debug("Lock %p locked by %p\t%p", Lock, __builtin_return_address(0), __builtin_return_address(1));
+		Debug("got it");
+	}
+	#endif
+}
+/**
+ * \brief Release a short lock
+ * \param Lock	Lock pointer
+ */
+void SHORTREL(struct sShortSpinlock *Lock)
+{	
+	#if STACKED_LOCKS
+	if( Lock->Depth ) {
+		Lock->Depth --;
+		return ;
+	}
+	#endif
+	
+	#if TRACE_LOCKS
+	if( Lock != &glDebug_Lock && Lock != &glThreadListLock )
+	{
+		//Log_Log("LOCK", "%p released by %p", Lock, __builtin_return_address(0));
+		Debug("Lock %p released by %p\t%p", Lock, __builtin_return_address(0), __builtin_return_address(1));
+	}
+	#endif
+	
+	#if LOCK_DISABLE_INTS
+	// Lock->IF can change anytime once Lock->Lock is zeroed
+	if(Lock->IF) {
+		Lock->Lock = 0;
+		__ASM__ ("sti");
+	}
+	else {
+		Lock->Lock = 0;
+	}
+	#else
+	Lock->Lock = 0;
+	#endif
+}
+
+// === DEBUG IO ===
+#if USE_GDB_STUB
+int putDebugChar(char ch)
+{
+	if(!gbGDB_SerialSetup) {
+		outb(GDB_SERIAL_PORT + 1, 0x00);    // Disable all interrupts
+		outb(GDB_SERIAL_PORT + 3, 0x80);    // Enable DLAB (set baud rate divisor)
+		outb(GDB_SERIAL_PORT + 0, 0x0C);    // Set divisor to 12 (lo byte) 9600 baud
+		outb(GDB_SERIAL_PORT + 1, 0x00);    //  (base is         (hi byte)
+		outb(GDB_SERIAL_PORT + 3, 0x03);    // 8 bits, no parity, one stop bit (8N1)
+		outb(GDB_SERIAL_PORT + 2, 0xC7);    // Enable FIFO with 14-byte threshold and clear it
+		outb(GDB_SERIAL_PORT + 4, 0x0B);    // IRQs enabled, RTS/DSR set
+		gbGDB_SerialSetup = 1;
+	}
+	while( (inb(GDB_SERIAL_PORT + 5) & 0x20) == 0 );
+	outb(GDB_SERIAL_PORT, ch);
+	return 0;
+}
+int getDebugChar(void)
+{
+	if(!gbGDB_SerialSetup) {
+		outb(GDB_SERIAL_PORT + 1, 0x00);    // Disable all interrupts
+		outb(GDB_SERIAL_PORT + 3, 0x80);    // Enable DLAB (set baud rate divisor)
+		outb(GDB_SERIAL_PORT + 0, 0x0C);    // Set divisor to 12 (lo byte) 9600 baud
+		outb(GDB_SERIAL_PORT + 1, 0x00);    //                   (hi byte)
+		outb(GDB_SERIAL_PORT + 3, 0x03);    // 8 bits, no parity, one stop bit
+		outb(GDB_SERIAL_PORT + 2, 0xC7);    // Enable FIFO with 14-byte threshold and clear it
+		outb(GDB_SERIAL_PORT + 4, 0x0B);    // IRQs enabled, RTS/DSR set
+		gbGDB_SerialSetup = 1;
+	}
+	while( (inb(GDB_SERIAL_PORT + 5) & 1) == 0)	;
+	return inb(GDB_SERIAL_PORT);
+}
+#endif	/* USE_GDB_STUB */
+
+void Debug_PutCharDebug(char ch)
+{
+	#if DEBUG_TO_E9
+	__asm__ __volatile__ ( "outb %%al, $0xe9" :: "a"(((Uint8)ch)) );
+	#endif
+	
+	#if DEBUG_TO_SERIAL
+	if(!gbDebug_SerialSetup) {
+		outb(SERIAL_PORT + 1, 0x00);	// Disable all interrupts
+		outb(SERIAL_PORT + 3, 0x80);	// Enable DLAB (set baud rate divisor)
+		outb(SERIAL_PORT + 0, 0x0C);	// Set divisor to 12 (lo byte) 9600 baud
+		outb(SERIAL_PORT + 1, 0x00);	//                   (hi byte)
+		outb(SERIAL_PORT + 3, 0x03);	// 8 bits, no parity, one stop bit
+		outb(SERIAL_PORT + 2, 0xC7);	// Enable FIFO with 14-byte threshold and clear it
+		outb(SERIAL_PORT + 4, 0x0B);	// IRQs enabled, RTS/DSR set
+		gbDebug_SerialSetup = 1;
+	}
+	while( (inb(SERIAL_PORT + 5) & 0x20) == 0 );
+	outb(SERIAL_PORT, ch);
+	#endif
 }
 
-void Release(int *lock)
+void Debug_PutStringDebug(const char *String)
 {
-	__asm__ __volatile__ ("lock andl $0, (%0)"::"r"(lock));
+	while(*String)
+		Debug_PutCharDebug(*String++);
 }
 
 // === IO Commands ===
@@ -79,13 +302,18 @@ void *memsetd(void *Dest, Uint32 Val, size_t Num)
  */
 int memcmp(const void *m1, const void *m2, size_t Num)
 {
+	const Uint8	*d1 = m1;
+	const Uint8	*d2 = m2;
+	if( Num == 0 )	return 0;	// No bytes are always identical
+	
 	while(Num--)
 	{
-		if(*(Uint8*)m1 != *(Uint8*)m2)	break;
-		m1 ++;
-		m2 ++;
+		if(*d1 != *d2)
+			return *d1 - *d2;
+		d1 ++;
+		d2 ++;
 	}
-	return *(Uint8*)m1 - *(Uint8*)m2;
+	return 0;
 }
 
 /**
@@ -115,6 +343,25 @@ void *memcpyd(void *Dest, const void *Src, size_t Num)
 	return Dest;
 }
 
+Uint64 DivMod64U(Uint64 Num, Uint64 Div, Uint64 *Rem)
+{
+	Uint64	ret;
+	if( Div < 0x100000000ULL && Num < 0xFFFFFFFF * Div ) {
+		Uint32	rem, ret_32;
+		__asm__ __volatile__(
+			"div %4"
+			: "=a" (ret_32), "=d" (rem)
+			: "a" ( (Uint32)(Num & 0xFFFFFFFF) ), "d" ((Uint32)(Num >> 32)), "r" (Div)
+			);
+		if(Rem)	*Rem = rem;
+		return ret_32;
+	}
+
+	ret = __udivdi3(Num, Div);
+	if(Rem)	*Rem = __umoddi3(Num, Div);
+	return ret;
+}
+
 /**
  * \fn Uint64 __udivdi3(Uint64 Num, Uint64 Den)
  * \brief Divide two 64-bit integers
@@ -142,6 +389,21 @@ Uint64 __udivdi3(Uint64 Num, Uint64 Den)
 	if(Num < Den*2)	return 1;
 	if(Num == Den*2)	return 2;
 	
+	#if 1
+	i = 0;	// Shut up
+	P[0] = Num;
+	P[1] = Den;
+	__asm__ __volatile__ (
+		"fildq %2\n\t"	// Num
+		"fildq %1\n\t"	// Den
+		"fdivp\n\t"
+		"fistpq %0"
+		: "=m" (q)
+		: "m" (P[0]), "m" (P[1])
+		);
+		
+	//Log("%llx / %llx = %llx\n", Num, Den, q);
+	#else
 	// Restoring division, from wikipedia
 	// http://en.wikipedia.org/wiki/Division_(digital)
 	P[0] = Num;	P[1] = 0;
@@ -163,6 +425,7 @@ Uint64 __udivdi3(Uint64 Num, Uint64 Den)
 			P[1] += Den;
 		}
 	}
+	#endif
 	
 	return q;
 }
@@ -190,22 +453,6 @@ Uint64 __umoddi3(Uint64 Num, Uint64 Den)
 	return Num - __udivdi3(Num, Den) * Den;
 }
 
-Uint16 LittleEndian16(Uint16 Val)
-{
-	return Val;
-}
-Uint16 BigEndian16(Uint16 Val)
-{
-	return ((Val&0xFF)<<8) | ((Val>>8)&0xFF);
-}
-Uint32 LittleEndian32(Uint32 Val)
-{
-	return Val;
-}
-Uint32 BigEndian32(Uint32 Val)
-{
-	return ((Val&0xFF)<<24) | ((Val&0xFF00)<<8) | ((Val>>8)&0xFF00) | ((Val>>24)&0xFF);
-}
 
 // --- EXPORTS ---
 EXPORT(memcpy);	EXPORT(memset);
@@ -216,5 +463,6 @@ EXPORT(inb);	EXPORT(inw);	EXPORT(ind);
 EXPORT(outb);	EXPORT(outw);	EXPORT(outd);
 EXPORT(__udivdi3);	EXPORT(__umoddi3);
 
-EXPORT(LittleEndian16);	EXPORT(BigEndian16);
-EXPORT(LittleEndian32);	EXPORT(BigEndian32);
+EXPORT(SHORTLOCK);
+EXPORT(SHORTREL);
+EXPORT(IS_LOCKED);