pagetable lab initialized

kernel/kernelvec.S

@@ -3,7 +3,7 @@
         # mode come here.
         #
         # the current stack is a kernel stack.
-        # push all registers, call kerneltrap().
+        # push registers, call kerneltrap().
         # when kerneltrap() returns, restore registers, return.
         #
 .globl kerneltrap
@@ -13,7 +13,7 @@ kernelvec:
         # make room to save registers.
         addi sp, sp, -256
 
-        # save the registers.
+        # save caller-saved registers.
         sd ra, 0(sp)
         sd sp, 8(sp)
         sd gp, 16(sp)
@@ -21,8 +21,6 @@ kernelvec:
         sd t0, 32(sp)
         sd t1, 40(sp)
         sd t2, 48(sp)
-        sd s0, 56(sp)
-        sd s1, 64(sp)
         sd a0, 72(sp)
         sd a1, 80(sp)
         sd a2, 88(sp)
@@ -31,16 +29,6 @@ kernelvec:
         sd a5, 112(sp)
         sd a6, 120(sp)
         sd a7, 128(sp)
-        sd s2, 136(sp)
-        sd s3, 144(sp)
-        sd s4, 152(sp)
-        sd s5, 160(sp)
-        sd s6, 168(sp)
-        sd s7, 176(sp)
-        sd s8, 184(sp)
-        sd s9, 192(sp)
-        sd s10, 200(sp)
-        sd s11, 208(sp)
         sd t3, 216(sp)
         sd t4, 224(sp)
         sd t5, 232(sp)
@@ -57,8 +45,6 @@ kernelvec:
         ld t0, 32(sp)
         ld t1, 40(sp)
         ld t2, 48(sp)
-        ld s0, 56(sp)
-        ld s1, 64(sp)
         ld a0, 72(sp)
         ld a1, 80(sp)
         ld a2, 88(sp)
@@ -67,16 +53,6 @@ kernelvec:
         ld a5, 112(sp)
         ld a6, 120(sp)
         ld a7, 128(sp)
-        ld s2, 136(sp)
-        ld s3, 144(sp)
-        ld s4, 152(sp)
-        ld s5, 160(sp)
-        ld s6, 168(sp)
-        ld s7, 176(sp)
-        ld s8, 184(sp)
-        ld s9, 192(sp)
-        ld s10, 200(sp)
-        ld s11, 208(sp)
         ld t3, 216(sp)
         ld t4, 224(sp)
         ld t5, 232(sp)
@@ -86,39 +62,3 @@ kernelvec:
 
         # return to whatever we were doing in the kernel.
         sret
-
-        #
-        # machine-mode timer interrupt.
-        #
-.globl timervec
-.align 4
-timervec:
-        # start.c has set up the memory that mscratch points to:
-        # scratch[0,8,16] : register save area.
-        # scratch[24] : address of CLINT's MTIMECMP register.
-        # scratch[32] : desired interval between interrupts.
-        
-        csrrw a0, mscratch, a0
-        sd a1, 0(a0)
-        sd a2, 8(a0)
-        sd a3, 16(a0)
-
-        # schedule the next timer interrupt
-        # by adding interval to mtimecmp.
-        ld a1, 24(a0) # CLINT_MTIMECMP(hart)
-        ld a2, 32(a0) # interval
-        ld a3, 0(a1)
-        add a3, a3, a2
-        sd a3, 0(a1)
-
-        # arrange for a supervisor software interrupt
-        # after this handler returns.
-        li a1, 2
-        csrw sip, a1
-
-        ld a3, 16(a0)
-        ld a2, 8(a0)
-        ld a1, 0(a0)
-        csrrw a0, mscratch, a0
-
-        mret