add init loongson soc3210 porting.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1012 bbd45198-f89e-11dd-88c7-29a3b14d5316

libcpu/mips/common/exception.h

@@ -140,8 +140,6 @@
 
 #define GDB_FR_SIZE			((((GDB_FR_CP0_PRID) + LONGSIZE) + (PTRSIZE-1)) & ~(PTRSIZE-1))
 
-
-
 /*
  * This is the same as above, but for the high-level
  * part of the INT stub.
@@ -161,7 +159,7 @@ typedef struct pt_regs_s
 
 typedef void (* exception_func_t)(pt_regs_t *regs);
 
-extern exception_func_t sys_exception_handlers[33];
+extern exception_func_t sys_exception_handlers[];
 exception_func_t rt_set_except_vector(int n, exception_func_t func);
 void install_default_execpt_handle(void);
 

libcpu/mips/common/mips.inc

@@ -14,15 +14,15 @@
 #ifndef __MIPS_INC__
 #define __MIPS_INC__
 
-#define zero    $0
-#define at      $1
-#define v0      $2
+#define zero    $0		/* wired zero */
+// #define at      $1
+#define v0      $2		/* return value */
 #define v1      $3
-#define a0      $4
+#define a0      $4		/* argument registers */
 #define a1      $5
 #define a2      $6
 #define a3      $7
-#define t0      $8
+#define t0      $8		/* caller saved */
 #define t1      $9
 #define t2      $10
 #define t3      $11
@@ -30,7 +30,7 @@
 #define t5      $13
 #define t6      $14
 #define t7      $15
-#define s0      $16
+#define s0      $16		/* callee saved */
 #define s1      $17
 #define s2      $18
 #define s3      $19
@@ -38,14 +38,15 @@
 #define s5      $21
 #define s6      $22
 #define s7      $23
-#define t8      $24
+#define t8      $24		/* caller saved */
 #define t9      $25
-#define k0      $26
+#define jp      $25     /* PIC jump register */
+#define k0      $26     /* kernel scratch */
 #define k1      $27
-#define gp      $28
-#define sp      $29
-#define fp      $30
-#define ra      $31
-
+#define gp      $28     /* global pointer */
+#define sp      $29     /* stack pointer */
+#define fp      $30     /* frame pointer */
+#define s8		$30		/* same like fp! */
+#define ra      $31     /* return address */
 
 #endif /* end of __MIPS_INC__   */