patch-2.4.19 linux-2.4.19/include/asm-mips64/mipsregs.h

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diff -urN linux-2.4.18/include/asm-mips64/mipsregs.h linux-2.4.19/include/asm-mips64/mipsregs.h
@@ -3,13 +3,16 @@
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
- * Copyright (C) 1994, 1995, 1996, 1997, 1999 by Ralf Baechle
+ * Copyright (C) 1994, 1995, 1996, 1997, 2000, 2001 by Ralf Baechle
+ * Copyright (C) 2000 Silicon Graphics, Inc.
  * Modified for further R[236]000 support by Paul M. Antoine, 1996.
- * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2000 MIPS Technologies, Inc.  All rights reserved.
  */
 #ifndef _ASM_MIPSREGS_H
 #define _ASM_MIPSREGS_H
 
+#include <linux/config.h>
 #include <linux/linkage.h>
 
 /*
@@ -30,6 +33,7 @@
 #define CP0_RANDOM $1
 #define CP0_ENTRYLO0 $2
 #define CP0_ENTRYLO1 $3
+#define CP0_CONF $3
 #define CP0_CONTEXT $4
 #define CP0_PAGEMASK $5
 #define CP0_WIRED $6
@@ -49,12 +53,41 @@
 #define CP0_XCONTEXT $20
 #define CP0_FRAMEMASK $21
 #define CP0_DIAGNOSTIC $22
+#define CP0_DEBUG $23
+#define CP0_DEPC $24
 #define CP0_PERFORMANCE $25
 #define CP0_ECC $26
 #define CP0_CACHEERR $27
 #define CP0_TAGLO $28
 #define CP0_TAGHI $29
 #define CP0_ERROREPC $30
+#define CP0_DESAVE $31
+
+/*
+ * R4640/R4650 cp0 register names.  These registers are listed
+ * here only for completeness; without MMU these CPUs are not useable
+ * by Linux.  A future ELKS port might take make Linux run on them
+ * though ...
+ */
+#define CP0_IBASE $0
+#define CP0_IBOUND $1
+#define CP0_DBASE $2
+#define CP0_DBOUND $3
+#define CP0_CALG $17
+#define CP0_IWATCH $18
+#define CP0_DWATCH $19
+
+/* 
+ * Coprocessor 0 Set 1 register names
+ */
+#define CP0_S1_DERRADDR0  $26
+#define CP0_S1_DERRADDR1  $27
+#define CP0_S1_INTCONTROL $20
+
+/*
+ *  TX39 Series
+ */
+#define CP0_TX39_CACHE	$7
 
 /*
  * Coprocessor 1 (FPU) register names
@@ -63,57 +96,96 @@
 #define CP1_STATUS     $31
 
 /*
- * Values for PageMask register
+ * FPU Status Register Values
  */
-#define PM_4K   0x00000000
-#define PM_16K  0x00006000
-#define PM_64K  0x0001e000
-#define PM_256K 0x0007e000
-#define PM_1M   0x001fe000
-#define PM_4M   0x007fe000
-#define PM_16M  0x01ffe000
-
 /*
- * Values used for computation of new tlb entries
+ * Status Register Values
  */
-#define PL_4K   12
-#define PL_16K  14
-#define PL_64K  16
-#define PL_256K 18
-#define PL_1M   20
-#define PL_4M   22
-#define PL_16M  24
+
+#define FPU_CSR_FLUSH   0x01000000      /* flush denormalised results to 0 */
+#define FPU_CSR_COND    0x00800000      /* $fcc0 */
+#define FPU_CSR_COND0   0x00800000      /* $fcc0 */
+#define FPU_CSR_COND1   0x02000000      /* $fcc1 */
+#define FPU_CSR_COND2   0x04000000      /* $fcc2 */
+#define FPU_CSR_COND3   0x08000000      /* $fcc3 */
+#define FPU_CSR_COND4   0x10000000      /* $fcc4 */
+#define FPU_CSR_COND5   0x20000000      /* $fcc5 */
+#define FPU_CSR_COND6   0x40000000      /* $fcc6 */
+#define FPU_CSR_COND7   0x80000000      /* $fcc7 */
+
+/*
+ * X the exception cause indicator
+ * E the exception enable
+ * S the sticky/flag bit
+*/
+#define FPU_CSR_ALL_X 0x0003f000
+#define FPU_CSR_UNI_X   0x00020000
+#define FPU_CSR_INV_X   0x00010000
+#define FPU_CSR_DIV_X   0x00008000
+#define FPU_CSR_OVF_X   0x00004000
+#define FPU_CSR_UDF_X   0x00002000
+#define FPU_CSR_INE_X   0x00001000
+
+#define FPU_CSR_ALL_E   0x00000f80
+#define FPU_CSR_INV_E   0x00000800
+#define FPU_CSR_DIV_E   0x00000400
+#define FPU_CSR_OVF_E   0x00000200
+#define FPU_CSR_UDF_E   0x00000100
+#define FPU_CSR_INE_E   0x00000080
+
+#define FPU_CSR_ALL_S   0x0000007c
+#define FPU_CSR_INV_S   0x00000040
+#define FPU_CSR_DIV_S   0x00000020
+#define FPU_CSR_OVF_S   0x00000010
+#define FPU_CSR_UDF_S   0x00000008
+#define FPU_CSR_INE_S   0x00000004
+
+/* rounding mode */
+#define FPU_CSR_RN      0x0     /* nearest */
+#define FPU_CSR_RZ      0x1     /* towards zero */
+#define FPU_CSR_RU      0x2     /* towards +Infinity */
+#define FPU_CSR_RD      0x3     /* towards -Infinity */
+
 
 /*
- * Macros to access the system control coprocessor
+ * Values for PageMask register
  */
-#define read_32bit_cp0_register(source)                         \
-({ int __res;                                                   \
-        __asm__ __volatile__(                                   \
-        "mfc0\t%0,"STR(source)                                  \
-        : "=r" (__res));                                        \
-        __res;})
+#ifdef CONFIG_CPU_VR41XX
 
-#define read_64bit_cp0_register(source)                         \
-({ int __res;                                                   \
-        __asm__ __volatile__(                                   \
-        ".set\tmips3\n\t"                                       \
-        "dmfc0\t%0,"STR(source)"\n\t"                           \
-        ".set\tmips0"                                           \
-        : "=r" (__res));                                        \
-        __res;})
+/* Why doesn't stupidity hurt ... */
 
-#define write_32bit_cp0_register(register,value)                \
-        __asm__ __volatile__(                                   \
-        "mtc0\t%0,"STR(register)                                \
-        : : "r" (value));
+#define PM_1K		0x00000000
+#define PM_4K		0x00001800
+#define PM_16K		0x00007800
+#define PM_64K		0x0001f800
+#define PM_256K		0x0007f800
+
+#else
+
+#define PM_4K		0x00000000
+#define PM_16K		0x00006000
+#define PM_64K		0x0001e000
+#define PM_256K		0x0007e000
+#define PM_1M		0x001fe000
+#define PM_4M		0x007fe000
+#define PM_16M		0x01ffe000
+#define PM_64M		0x07ffe000
+#define PM_256M		0x1fffe000
 
-#define write_64bit_cp0_register(register,value)                \
-        __asm__ __volatile__(                                   \
-        ".set\tmips3\n\t"                                       \
-        "dmtc0\t%0,"STR(register)"\n\t"                         \
-        ".set\tmips0"                                           \
-        : : "r" (value))
+#endif
+
+/*
+ * Values used for computation of new tlb entries
+ */
+#define PL_4K		12
+#define PL_16K		14
+#define PL_64K		16
+#define PL_256K		18
+#define PL_1M		20
+#define PL_4M		22
+#define PL_16M		24
+#define PL_64M		26
+#define PL_256M		28
 
 /*
  * R4x00 interrupt enable / cause bits
@@ -139,31 +211,6 @@
 #define C_IRQ4          (1<<14)
 #define C_IRQ5          (1<<15)
 
-#ifndef _LANGUAGE_ASSEMBLY
-/*
- * Manipulate the status register.
- * Mostly used to access the interrupt bits.
- */
-#define __BUILD_SET_CP0(name,register)                          \
-extern __inline__ unsigned int                                  \
-set_cp0_##name(unsigned int change, unsigned int new)           \
-{                                                               \
-	unsigned int res;                                       \
-                                                                \
-	res = read_32bit_cp0_register(register);                \
-	res &= ~change;                                         \
-	res |= (new & change);                                  \
-	write_32bit_cp0_register(register, res);                \
-                                                                \
-	return res;                                             \
-}
-
-__BUILD_SET_CP0(status,CP0_STATUS)
-__BUILD_SET_CP0(cause,CP0_CAUSE)
-__BUILD_SET_CP0(config,CP0_CONFIG)
-
-#endif /* defined (_LANGUAGE_ASSEMBLY) */
-
 /*
  * Bitfields in the R4xx0 cp0 status register
  */
@@ -181,6 +228,60 @@
 #define ST0_CE			0x00020000
 
 /*
+ * Bitfields in the R[23]000 cp0 status register.
+ */
+#define ST0_IEC                 0x00000001
+#define ST0_KUC			0x00000002
+#define ST0_IEP			0x00000004
+#define ST0_KUP			0x00000008
+#define ST0_IEO			0x00000010
+#define ST0_KUO			0x00000020
+/* bits 6 & 7 are reserved on R[23]000 */
+#define ST0_ISC			0x00010000
+#define ST0_SWC			0x00020000
+#define ST0_CM			0x00080000
+
+/*
+ * Bits specific to the R4640/R4650
+ */
+#define ST0_UM                 (1   <<  4)
+#define ST0_IL                 (1   << 23)
+#define ST0_DL                 (1   << 24)
+
+/*
+ * Bitfields in the TX39 family CP0 Configuration Register 3
+ */
+#define TX39_CONF_ICS_SHIFT	19
+#define TX39_CONF_ICS_MASK	0x00380000
+#define TX39_CONF_ICS_1KB 	0x00000000
+#define TX39_CONF_ICS_2KB 	0x00080000
+#define TX39_CONF_ICS_4KB 	0x00100000
+#define TX39_CONF_ICS_8KB 	0x00180000
+#define TX39_CONF_ICS_16KB 	0x00200000
+
+#define TX39_CONF_DCS_SHIFT	16
+#define TX39_CONF_DCS_MASK	0x00070000
+#define TX39_CONF_DCS_1KB 	0x00000000
+#define TX39_CONF_DCS_2KB 	0x00010000
+#define TX39_CONF_DCS_4KB 	0x00020000
+#define TX39_CONF_DCS_8KB 	0x00030000
+#define TX39_CONF_DCS_16KB 	0x00040000
+
+#define TX39_CONF_CWFON 	0x00004000
+#define TX39_CONF_WBON  	0x00002000
+#define TX39_CONF_RF_SHIFT	10
+#define TX39_CONF_RF_MASK	0x00000c00
+#define TX39_CONF_DOZE		0x00000200
+#define TX39_CONF_HALT		0x00000100
+#define TX39_CONF_LOCK		0x00000080
+#define TX39_CONF_ICE		0x00000020
+#define TX39_CONF_DCE		0x00000010
+#define TX39_CONF_IRSIZE_SHIFT	2
+#define TX39_CONF_IRSIZE_MASK	0x0000000c
+#define TX39_CONF_DRSIZE_SHIFT	0
+#define TX39_CONF_DRSIZE_MASK	0x00000003
+
+/*
  * Status register bits available in all MIPS CPUs.
  */
 #define ST0_IM			0x0000ff00
@@ -200,6 +301,22 @@
 #define  STATUSF_IP6		(1   << 14)
 #define  STATUSB_IP7		15
 #define  STATUSF_IP7		(1   << 15)
+#define  STATUSB_IP8		0
+#define  STATUSF_IP8		(1   << 0)
+#define  STATUSB_IP9		1
+#define  STATUSF_IP9		(1   << 1)
+#define  STATUSB_IP10		2
+#define  STATUSF_IP10		(1   << 2)
+#define  STATUSB_IP11		3
+#define  STATUSF_IP11		(1   << 3)
+#define  STATUSB_IP12		4
+#define  STATUSF_IP12		(1   << 4)
+#define  STATUSB_IP13		5
+#define  STATUSF_IP13		(1   << 5)
+#define  STATUSB_IP14		6
+#define  STATUSF_IP14		(1   << 6)
+#define  STATUSB_IP15		7
+#define  STATUSF_IP15		(1   << 7)
 #define ST0_CH			0x00040000
 #define ST0_SR			0x00100000
 #define ST0_TS			0x00200000
@@ -246,7 +363,7 @@
 #define  CAUSEF_BD		(1   << 31)
 
 /*
- * Bits in the coprocessor 0 config register.
+ * Bits in the coprozessor 0 config register.
  */
 #define CONF_CM_CACHABLE_NO_WA		0
 #define CONF_CM_CACHABLE_WA		1
@@ -260,12 +377,22 @@
 #define CONF_DB				(1 <<  4)
 #define CONF_IB				(1 <<  5)
 #define CONF_SC				(1 << 17)
+#define CONF_AC                         (1 << 23)
+#define CONF_HALT                       (1 << 25)
+
+/*
+ * Bits in the TX49 coprozessor 0 config register.
+ */
+#define TX49_CONF_DC			(1 << 16)
+#define TX49_CONF_IC			(1 << 17)  /* conflict with CONF_SC */
+#define TX49_CONF_HALT			(1 << 18)
+#define TX49_CONF_CWFON			(1 << 27)
 
 /*
  * R10000 performance counter definitions.
  *
  * FIXME: The R10000 performance counter opens a nice way to implement CPU
- *        time accounting with a precision of one cycle.  I don't have
+ *        time accounting with a precission of one cycle.  I don't have
  *        R10000 silicon but just a manual, so ...
  */
 
@@ -317,14 +444,479 @@
 #define CEB_KERNEL	2	/* Count events in kernel mode EXL = ERL = 0 */
 #define CEB_EXL		1	/* Count events with EXL = 1, ERL = 0 */
 
-#ifndef _LANGUAGE_ASSEMBLY
+#ifndef __ASSEMBLY__
+
 /*
- * Functions to access the performance counter and control registers
+ * Functions to access the r10k performance counter and control registers
  */
-extern asmlinkage unsigned int read_perf_cntr(unsigned int counter);
-extern asmlinkage void write_perf_cntr(unsigned int counter, unsigned int val);
-extern asmlinkage unsigned int read_perf_cntl(unsigned int counter);
-extern asmlinkage void write_perf_cntl(unsigned int counter, unsigned int val);
-#endif
+#define read_r10k_perf_cntr(counter)                            \
+({ unsigned int __res;                                          \
+        __asm__ __volatile__(                                   \
+        "mfpc\t%0, "STR(counter)                                \
+        : "=r" (__res));                                        \
+        __res;})
+
+#define write_r10k_perf_cntr(counter,val)                       \
+        __asm__ __volatile__(                                   \
+        "mtpc\t%0, "STR(counter)                                \
+        : : "r" (val));
+
+#define read_r10k_perf_cntl(counter)                            \
+({ unsigned int __res;                                          \
+        __asm__ __volatile__(                                   \
+        "mfps\t%0, "STR(counter)                                \
+        : "=r" (__res));                                        \
+        __res;})
+
+#define write_r10k_perf_cntl(counter,val)                       \
+        __asm__ __volatile__(                                   \
+        "mtps\t%0, "STR(counter)                                \
+        : : "r" (val));
+
+/*
+ * Macros to access the system control coprocessor
+ */
+#define read_32bit_cp0_register(source)                         \
+({ int __res;                                                   \
+        __asm__ __volatile__(                                   \
+        "mfc0\t%0,"STR(source)                                  \
+        : "=r" (__res));                                        \
+        __res;})
+
+#define read_64bit_cp0_register(source)                         \
+({ unsigned long __res;                                         \
+        __asm__ __volatile__(                                   \
+        ".set\tmips3\n\t"                                       \
+        "dmfc0\t%0,"STR(source)"\n\t"                           \
+        ".set\tmips0"                                           \
+        : "=r" (__res));                                        \
+        __res;})
+
+#define write_32bit_cp0_register(register,value)                \
+        __asm__ __volatile__(                                   \
+        "mtc0\t%0,"STR(register)                                \
+        : : "r" (value));
+
+#define write_64bit_cp0_register(register,value)                \
+        __asm__ __volatile__(                                   \
+        ".set\tmips3\n\t"                                       \
+        "dmtc0\t%0,"STR(register)"\n\t"                         \
+        ".set\tmips0"                                           \
+        : : "r" (value))
+
+/* 
+ * This should be changed when we get a compiler that support the MIPS32 ISA. 
+ */
+#define read_mips32_cp0_config1()                               \
+({ int __res;                                                   \
+        __asm__ __volatile__(                                   \
+	".set\tnoreorder\n\t"                                   \
+	".set\tnoat\n\t"                                        \
+	"#.set\tmips64\n\t"					\
+	"#mfc0\t$1, $16, 1\n\t"					\
+	"#.set\tmips0\n\t"					\
+     	".word\t0x40018001\n\t"                                 \
+	"move\t%0,$1\n\t"                                       \
+	".set\tat\n\t"                                          \
+	".set\treorder"                                         \
+	:"=r" (__res));                                         \
+        __res;})
+
+/*
+ * Macros to access the floating point coprocessor control registers
+ */
+#define read_32bit_cp1_register(source)                         \
+({ int __res;                                                   \
+        __asm__ __volatile__(                                   \
+	".set\tpush\n\t"					\
+	".set\treorder\n\t"					\
+        "cfc1\t%0,"STR(source)"\n\t"                            \
+	".set\tpop"						\
+        : "=r" (__res));                                        \
+        __res;})
+
+/* TLB operations. */
+static inline void tlb_probe(void)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"tlbp\n\t"
+		".set reorder");
+}
+
+static inline void tlb_read(void)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"tlbr\n\t"
+		".set reorder");
+}
+
+static inline void tlb_write_indexed(void)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"tlbwi\n\t"
+		".set reorder");
+}
+
+static inline void tlb_write_random(void)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"tlbwr\n\t"
+		".set reorder");
+}
+
+/* Dealing with various CP0 mmu/cache related registers. */
+
+/* CP0_PAGEMASK register */
+static inline unsigned long get_pagemask(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mfc0 %0, $5\n\t"
+		".set reorder"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_pagemask(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mtc0 %z0, $5\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+/* CP0_ENTRYLO0 and CP0_ENTRYLO1 registers */
+static inline unsigned long get_entrylo0(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(	
+		".set noreorder\n\t"
+		"dmfc0 %0, $2\n\t"
+		".set reorder"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_entrylo0(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmtc0 %z0, $2\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+static inline unsigned long get_entrylo1(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmfc0 %0, $3\n\t"
+		".set reorder" : "=r" (val));
+
+	return val;
+}
+
+static inline void set_entrylo1(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmtc0 %z0, $3\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+/* CP0_ENTRYHI register */
+static inline unsigned long get_entryhi(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmfc0 %0, $10\n\t"
+		".set reorder"
+		: "=r" (val));
+
+	return val;
+}
+
+static inline void set_entryhi(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmtc0 %z0, $10\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+/* CP0_INDEX register */
+static inline unsigned int get_index(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mfc0 %0, $0\n\t"
+		".set reorder"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_index(unsigned int val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mtc0 %z0, $0\n\t"
+		".set reorder\n\t"
+		: : "Jr" (val));
+}
+
+/* CP0_WIRED register */
+static inline unsigned long get_wired(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mfc0 %0, $6\n\t"
+		".set reorder\n\t"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_wired(unsigned long val)
+{
+	__asm__ __volatile__(
+		"\n\t.set noreorder\n\t"
+		"mtc0 %z0, $6\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+static inline unsigned long get_info(void)
+{
+	unsigned long val;
+
+	__asm__(".set push\n\t"
+		".set reorder\n\t"
+		"mfc0 %0, $7\n\t"
+		".set pop"
+		: "=r" (val));
+	return val;
+}
+
+/* CP0_STATUS registers */
+static inline unsigned long get_status(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mfc0 %0, $12\n\t"
+		".set reorder"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_status(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mtc0 %z0, $12\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+/* CP0_TAGLO and CP0_TAGHI registers */
+static inline unsigned long get_taglo(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mfc0 %0, $28\n\t"
+		".set reorder"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_taglo(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mtc0 %z0, $28\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+static inline unsigned long get_taghi(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mfc0 %0, $29\n\t"
+		".set reorder"
+		: "=r" (val));
+	return val;
+}
+
+static inline void set_taghi(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"mtc0 %z0, $29\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+static inline unsigned long get_context(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmfc0 %0, $4\n\t"
+		".set reorder"
+		: "=r" (val));
+
+	return val;
+}
+
+static inline void set_context(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmtc0 %z0, $4\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+static inline unsigned long get_xcontext(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmfc0 %0, $20\n\t"
+		".set reorder"
+		: "=r" (val));
+
+	return val;
+}
+
+static inline void set_xcontext(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set noreorder\n\t"
+		"dmtc0 %z0, $20\n\t"
+		".set reorder"
+		: : "Jr" (val));
+}
+
+static inline unsigned long get_errorepc(void)
+{
+	unsigned long val;
+
+	__asm__ __volatile__(
+		".set push\n\t"
+		".set reorder\n\t"
+		"dmfc0 %0, $30\n\t"
+		".set pop"
+		: "=r" (val));
+
+	return val;
+}
+
+static inline void set_errorepc(unsigned long val)
+{
+	__asm__ __volatile__(
+		".set push\n\t"
+		".set reorder\n\t"
+		"dmtc0 %z0, $30\n\t"
+		".set pop"
+		: : "Jr" (val));
+}
+
+/*
+ * Manipulate the status register.
+ * Mostly used to access the interrupt bits.
+ */
+#define __BUILD_SET_CP0(name,register)				\
+static inline unsigned int					\
+set_cp0_##name(unsigned int set)				\
+{								\
+	unsigned int res;					\
+								\
+	res = read_32bit_cp0_register(register);		\
+	res |= set;						\
+	write_32bit_cp0_register(register, res);		\
+								\
+	return res;						\
+}								\
+								\
+static inline unsigned int					\
+clear_cp0_##name(unsigned int clear)				\
+{								\
+	unsigned int res;					\
+								\
+	res = read_32bit_cp0_register(register);		\
+	res &= ~clear;						\
+	write_32bit_cp0_register(register, res);		\
+								\
+	return res;						\
+}								\
+								\
+static inline unsigned int					\
+change_cp0_##name(unsigned int change, unsigned int new)	\
+{								\
+	unsigned int res;					\
+								\
+	res = read_32bit_cp0_register(register);		\
+	res &= ~change;						\
+	res |= (new & change);					\
+	if (change)						\
+		write_32bit_cp0_register(register, res);	\
+								\
+	return res;						\
+}
+
+__BUILD_SET_CP0(status,CP0_STATUS)
+__BUILD_SET_CP0(cause,CP0_CAUSE)
+__BUILD_SET_CP0(config,CP0_CONFIG)
+
+#define __enable_fpu()							\
+do {									\
+	set_cp0_status(ST0_CU1);					\
+	asm("nop;nop;nop;nop");		/* max. hazard */		\
+} while (0)
+
+#define __disable_fpu()							\
+do {									\
+	clear_cp0_status(ST0_CU1);					\
+	/* We don't care about the cp0 hazard here  */			\
+} while (0)
+
+#define enable_fpu()							\
+do {									\
+	if (mips_cpu.options & MIPS_CPU_FPU)				\
+		__enable_fpu();						\
+} while (0)
+
+#define disable_fpu()							\
+do {									\
+	if (mips_cpu.options & MIPS_CPU_FPU)				\
+		__disable_fpu();					\
+} while (0)
+#endif /* !__ASSEMBLY__ */
 
 #endif /* _ASM_MIPSREGS_H */

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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)