651 lines
		
	
	
	
		
			17 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			651 lines
		
	
	
	
		
			17 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|   | /* | ||
|  | * This file is subject to the terms and conditions of the GNU General Public | ||
|  | * License.  See the file "COPYING" in the main directory of this archive | ||
|  | * for more details. | ||
|  | * | ||
|  | * Main entry point for the guest, exception handling. | ||
|  | * | ||
|  | * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved. | ||
|  | * Authors: Sanjay Lal <sanjayl@kymasys.com>
 | ||
|  | */ | ||
|  | 
 | ||
|  | #include <asm/asm.h> | ||
|  | #include <asm/asmmacro.h> | ||
|  | #include <asm/regdef.h> | ||
|  | #include <asm/mipsregs.h> | ||
|  | #include <asm/stackframe.h> | ||
|  | #include <asm/asm-offsets.h> | ||
|  | 
 | ||
|  | 
 | ||
|  | #define _C_LABEL(x)     x | ||
|  | #define MIPSX(name)     mips32_ ## name | ||
|  | #define CALLFRAME_SIZ   32 | ||
|  | 
 | ||
|  | /* | ||
|  |  * VECTOR | ||
|  |  *  exception vector entrypoint | ||
|  |  */ | ||
|  | #define VECTOR(x, regmask)      \ | ||
|  |     .ent    _C_LABEL(x),0;      \
 | ||
|  |     EXPORT(x);
 | ||
|  | 
 | ||
|  | #define VECTOR_END(x)      \ | ||
|  |     EXPORT(x);
 | ||
|  | 
 | ||
|  | /* Overload, Danger Will Robinson!! */ | ||
|  | #define PT_HOST_ASID        PT_BVADDR | ||
|  | #define PT_HOST_USERLOCAL   PT_EPC | ||
|  | 
 | ||
|  | #define CP0_DDATA_LO        $28,3 | ||
|  | #define CP0_EBASE           $15,1 | ||
|  | 
 | ||
|  | #define CP0_INTCTL          $12,1 | ||
|  | #define CP0_SRSCTL          $12,2 | ||
|  | #define CP0_SRSMAP          $12,3 | ||
|  | #define CP0_HWRENA          $7,0 | ||
|  | 
 | ||
|  | /* Resume Flags */ | ||
|  | #define RESUME_FLAG_HOST        (1<<1)  /* Resume host? */ | ||
|  | 
 | ||
|  | #define RESUME_GUEST            0 | ||
|  | #define RESUME_HOST             RESUME_FLAG_HOST | ||
|  | 
 | ||
|  | /* | ||
|  |  * __kvm_mips_vcpu_run: entry point to the guest | ||
|  |  * a0: run | ||
|  |  * a1: vcpu | ||
|  |  */ | ||
|  | 
 | ||
|  | FEXPORT(__kvm_mips_vcpu_run) | ||
|  |     .set    push
 | ||
|  |     .set    noreorder
 | ||
|  |     .set    noat
 | ||
|  | 
 | ||
|  |     /* k0/k1 not being used in host kernel context */ | ||
|  | 	addiu  		k1,sp, -PT_SIZE | ||
|  |     LONG_S	    $0, PT_R0(k1) | ||
|  |     LONG_S     	$1, PT_R1(k1) | ||
|  |     LONG_S     	$2, PT_R2(k1) | ||
|  |     LONG_S     	$3, PT_R3(k1) | ||
|  | 
 | ||
|  |     LONG_S     	$4, PT_R4(k1) | ||
|  |     LONG_S     	$5, PT_R5(k1) | ||
|  |     LONG_S     	$6, PT_R6(k1) | ||
|  |     LONG_S     	$7, PT_R7(k1) | ||
|  | 
 | ||
|  |     LONG_S     	$8,  PT_R8(k1) | ||
|  |     LONG_S     	$9,  PT_R9(k1) | ||
|  |     LONG_S     	$10, PT_R10(k1) | ||
|  |     LONG_S     	$11, PT_R11(k1) | ||
|  |     LONG_S     	$12, PT_R12(k1) | ||
|  |     LONG_S     	$13, PT_R13(k1) | ||
|  |     LONG_S     	$14, PT_R14(k1) | ||
|  |     LONG_S     	$15, PT_R15(k1) | ||
|  |     LONG_S     	$16, PT_R16(k1) | ||
|  |     LONG_S     	$17, PT_R17(k1) | ||
|  | 
 | ||
|  |     LONG_S     	$18, PT_R18(k1) | ||
|  |     LONG_S     	$19, PT_R19(k1) | ||
|  |     LONG_S     	$20, PT_R20(k1) | ||
|  |     LONG_S     	$21, PT_R21(k1) | ||
|  |     LONG_S     	$22, PT_R22(k1) | ||
|  |     LONG_S     	$23, PT_R23(k1) | ||
|  |     LONG_S     	$24, PT_R24(k1) | ||
|  |     LONG_S     	$25, PT_R25(k1) | ||
|  | 
 | ||
|  | 	/* XXXKYMA k0/k1 not saved, not being used if we got here through an ioctl() */ | ||
|  | 
 | ||
|  |     LONG_S     	$28, PT_R28(k1) | ||
|  |     LONG_S     	$29, PT_R29(k1) | ||
|  |     LONG_S     	$30, PT_R30(k1) | ||
|  |     LONG_S     	$31, PT_R31(k1) | ||
|  | 
 | ||
|  |     /* Save hi/lo */ | ||
|  | 	mflo		v0 | ||
|  | 	LONG_S		v0, PT_LO(k1) | ||
|  | 	mfhi   		v1 | ||
|  | 	LONG_S		v1, PT_HI(k1) | ||
|  | 
 | ||
|  | 	/* Save host status */ | ||
|  | 	mfc0		v0, CP0_STATUS | ||
|  | 	LONG_S		v0, PT_STATUS(k1) | ||
|  | 
 | ||
|  | 	/* Save host ASID, shove it into the BVADDR location */ | ||
|  | 	mfc0 		v1,CP0_ENTRYHI | ||
|  | 	andi		v1, 0xff | ||
|  | 	LONG_S		v1, PT_HOST_ASID(k1) | ||
|  | 
 | ||
|  |     /* Save DDATA_LO, will be used to store pointer to vcpu */ | ||
|  |     mfc0        v1, CP0_DDATA_LO | ||
|  |     LONG_S      v1, PT_HOST_USERLOCAL(k1) | ||
|  | 
 | ||
|  |     /* DDATA_LO has pointer to vcpu */ | ||
|  |     mtc0        a1,CP0_DDATA_LO | ||
|  | 
 | ||
|  |     /* Offset into vcpu->arch */ | ||
|  | 	addiu		k1, a1, VCPU_HOST_ARCH | ||
|  | 
 | ||
|  |     /* Save the host stack to VCPU, used for exception processing when we exit from the Guest */ | ||
|  |     LONG_S      sp, VCPU_HOST_STACK(k1) | ||
|  | 
 | ||
|  |     /* Save the kernel gp as well */ | ||
|  |     LONG_S      gp, VCPU_HOST_GP(k1) | ||
|  | 
 | ||
|  | 	/* Setup status register for running the guest in UM, interrupts are disabled */ | ||
|  | 	li			k0,(ST0_EXL | KSU_USER| ST0_BEV) | ||
|  | 	mtc0		k0,CP0_STATUS | ||
|  |     ehb | ||
|  | 
 | ||
|  |     /* load up the new EBASE */ | ||
|  |     LONG_L      k0, VCPU_GUEST_EBASE(k1) | ||
|  |     mtc0        k0,CP0_EBASE | ||
|  | 
 | ||
|  |     /* Now that the new EBASE has been loaded, unset BEV, set interrupt mask as it was | ||
|  |      * but make sure that timer interrupts are enabled | ||
|  |      */ | ||
|  |     li          k0,(ST0_EXL | KSU_USER | ST0_IE) | ||
|  |     andi        v0, v0, ST0_IM | ||
|  |     or          k0, k0, v0 | ||
|  |     mtc0        k0,CP0_STATUS | ||
|  |     ehb | ||
|  | 
 | ||
|  | 
 | ||
|  | 	/* Set Guest EPC */ | ||
|  | 	LONG_L		t0, VCPU_PC(k1) | ||
|  | 	mtc0		t0, CP0_EPC | ||
|  | 
 | ||
|  | FEXPORT(__kvm_mips_load_asid) | ||
|  |     /* Set the ASID for the Guest Kernel */ | ||
|  |     sll         t0, t0, 1                       /* with kseg0 @ 0x40000000, kernel */
 | ||
|  |                                                 /* addresses shift to 0x80000000 */ | ||
|  |     bltz        t0, 1f                          /* If kernel */ | ||
|  | 	addiu       t1, k1, VCPU_GUEST_KERNEL_ASID  /* (BD)  */ | ||
|  |     addiu       t1, k1, VCPU_GUEST_USER_ASID    /* else user */ | ||
|  | 1: | ||
|  |     /* t1: contains the base of the ASID array, need to get the cpu id  */ | ||
|  |     LONG_L      t2, TI_CPU($28)             /* smp_processor_id */ | ||
|  |     sll         t2, t2, 2                   /* x4 */ | ||
|  |     addu        t3, t1, t2 | ||
|  |     LONG_L      k0, (t3) | ||
|  |     andi        k0, k0, 0xff | ||
|  | 	mtc0		k0,CP0_ENTRYHI | ||
|  |     ehb | ||
|  | 
 | ||
|  |     /* Disable RDHWR access */ | ||
|  |     mtc0    zero,  CP0_HWRENA | ||
|  | 
 | ||
|  |     /* Now load up the Guest Context from VCPU */ | ||
|  |     LONG_L     	$1, VCPU_R1(k1) | ||
|  |     LONG_L     	$2, VCPU_R2(k1) | ||
|  |     LONG_L     	$3, VCPU_R3(k1) | ||
|  | 
 | ||
|  |     LONG_L     	$4, VCPU_R4(k1) | ||
|  |     LONG_L     	$5, VCPU_R5(k1) | ||
|  |     LONG_L     	$6, VCPU_R6(k1) | ||
|  |     LONG_L     	$7, VCPU_R7(k1) | ||
|  | 
 | ||
|  |     LONG_L     	$8,  VCPU_R8(k1) | ||
|  |     LONG_L     	$9,  VCPU_R9(k1) | ||
|  |     LONG_L     	$10, VCPU_R10(k1) | ||
|  |     LONG_L     	$11, VCPU_R11(k1) | ||
|  |     LONG_L     	$12, VCPU_R12(k1) | ||
|  |     LONG_L     	$13, VCPU_R13(k1) | ||
|  |     LONG_L     	$14, VCPU_R14(k1) | ||
|  |     LONG_L     	$15, VCPU_R15(k1) | ||
|  |     LONG_L     	$16, VCPU_R16(k1) | ||
|  |     LONG_L     	$17, VCPU_R17(k1) | ||
|  |     LONG_L     	$18, VCPU_R18(k1) | ||
|  |     LONG_L     	$19, VCPU_R19(k1) | ||
|  |     LONG_L     	$20, VCPU_R20(k1) | ||
|  |     LONG_L     	$21, VCPU_R21(k1) | ||
|  |     LONG_L     	$22, VCPU_R22(k1) | ||
|  |     LONG_L     	$23, VCPU_R23(k1) | ||
|  |     LONG_L     	$24, VCPU_R24(k1) | ||
|  |     LONG_L     	$25, VCPU_R25(k1) | ||
|  | 
 | ||
|  |     /* k0/k1 loaded up later */ | ||
|  | 
 | ||
|  |     LONG_L     	$28, VCPU_R28(k1) | ||
|  |     LONG_L     	$29, VCPU_R29(k1) | ||
|  |     LONG_L     	$30, VCPU_R30(k1) | ||
|  |     LONG_L     	$31, VCPU_R31(k1) | ||
|  | 
 | ||
|  |     /* Restore hi/lo */ | ||
|  | 	LONG_L		k0, VCPU_LO(k1) | ||
|  | 	mtlo		k0 | ||
|  | 
 | ||
|  | 	LONG_L		k0, VCPU_HI(k1) | ||
|  | 	mthi   		k0 | ||
|  | 
 | ||
|  | FEXPORT(__kvm_mips_load_k0k1) | ||
|  | 	/* Restore the guest's k0/k1 registers */ | ||
|  |     LONG_L     	k0, VCPU_R26(k1) | ||
|  |     LONG_L     	k1, VCPU_R27(k1) | ||
|  | 
 | ||
|  |     /* Jump to guest */ | ||
|  | 	eret | ||
|  | 	.set	pop
 | ||
|  | 
 | ||
|  | VECTOR(MIPSX(exception), unknown) | ||
|  | /* | ||
|  |  * Find out what mode we came from and jump to the proper handler. | ||
|  |  */ | ||
|  |     .set    push
 | ||
|  | 	.set	noat
 | ||
|  |     .set    noreorder
 | ||
|  |     mtc0    k0, CP0_ERROREPC    #01: Save guest k0 | ||
|  |     ehb                         #02: | ||
|  | 
 | ||
|  |     mfc0    k0, CP0_EBASE       #02: Get EBASE | ||
|  |     srl     k0, k0, 10          #03: Get rid of CPUNum | ||
|  |     sll     k0, k0, 10          #04 | ||
|  |     LONG_S  k1, 0x3000(k0)      #05: Save k1 @ offset 0x3000
 | ||
|  |     addiu   k0, k0, 0x2000      #06: Exception handler is installed @ offset 0x2000
 | ||
|  | 	j	k0				        #07: jump to the function | ||
|  | 	nop				        	#08: branch delay slot | ||
|  | 	.set	push
 | ||
|  | VECTOR_END(MIPSX(exceptionEnd)) | ||
|  | .end MIPSX(exception) | ||
|  | 
 | ||
|  | /* | ||
|  |  * Generic Guest exception handler. We end up here when the guest | ||
|  |  * does something that causes a trap to kernel mode. | ||
|  |  * | ||
|  |  */ | ||
|  | NESTED (MIPSX(GuestException), CALLFRAME_SIZ, ra) | ||
|  |     .set    push
 | ||
|  |     .set    noat
 | ||
|  |     .set    noreorder
 | ||
|  | 
 | ||
|  |     /* Get the VCPU pointer from DDTATA_LO */ | ||
|  |     mfc0        k1, CP0_DDATA_LO | ||
|  | 	addiu		k1, k1, VCPU_HOST_ARCH | ||
|  | 
 | ||
|  |     /* Start saving Guest context to VCPU */ | ||
|  |     LONG_S  $0, VCPU_R0(k1) | ||
|  |     LONG_S  $1, VCPU_R1(k1) | ||
|  |     LONG_S  $2, VCPU_R2(k1) | ||
|  |     LONG_S  $3, VCPU_R3(k1) | ||
|  |     LONG_S  $4, VCPU_R4(k1) | ||
|  |     LONG_S  $5, VCPU_R5(k1) | ||
|  |     LONG_S  $6, VCPU_R6(k1) | ||
|  |     LONG_S  $7, VCPU_R7(k1) | ||
|  |     LONG_S  $8, VCPU_R8(k1) | ||
|  |     LONG_S  $9, VCPU_R9(k1) | ||
|  |     LONG_S  $10, VCPU_R10(k1) | ||
|  |     LONG_S  $11, VCPU_R11(k1) | ||
|  |     LONG_S  $12, VCPU_R12(k1) | ||
|  |     LONG_S  $13, VCPU_R13(k1) | ||
|  |     LONG_S  $14, VCPU_R14(k1) | ||
|  |     LONG_S  $15, VCPU_R15(k1) | ||
|  |     LONG_S  $16, VCPU_R16(k1) | ||
|  |     LONG_S  $17,VCPU_R17(k1) | ||
|  |     LONG_S  $18, VCPU_R18(k1) | ||
|  |     LONG_S  $19, VCPU_R19(k1) | ||
|  |     LONG_S  $20, VCPU_R20(k1) | ||
|  |     LONG_S  $21, VCPU_R21(k1) | ||
|  |     LONG_S  $22, VCPU_R22(k1) | ||
|  |     LONG_S  $23, VCPU_R23(k1) | ||
|  |     LONG_S  $24, VCPU_R24(k1) | ||
|  |     LONG_S  $25, VCPU_R25(k1) | ||
|  | 
 | ||
|  |     /* Guest k0/k1 saved later */ | ||
|  | 
 | ||
|  |     LONG_S  $28, VCPU_R28(k1) | ||
|  |     LONG_S  $29, VCPU_R29(k1) | ||
|  |     LONG_S  $30, VCPU_R30(k1) | ||
|  |     LONG_S  $31, VCPU_R31(k1) | ||
|  | 
 | ||
|  |     /* We need to save hi/lo and restore them on | ||
|  |      * the way out | ||
|  |      */ | ||
|  |     mfhi    t0 | ||
|  |     LONG_S  t0, VCPU_HI(k1) | ||
|  | 
 | ||
|  |     mflo    t0 | ||
|  |     LONG_S  t0, VCPU_LO(k1) | ||
|  | 
 | ||
|  |     /* Finally save guest k0/k1 to VCPU */ | ||
|  |     mfc0    t0, CP0_ERROREPC | ||
|  |     LONG_S  t0, VCPU_R26(k1) | ||
|  | 
 | ||
|  |     /* Get GUEST k1 and save it in VCPU */ | ||
|  |     la      t1, ~0x2ff | ||
|  |     mfc0    t0, CP0_EBASE | ||
|  |     and     t0, t0, t1 | ||
|  |     LONG_L  t0, 0x3000(t0) | ||
|  |     LONG_S  t0, VCPU_R27(k1) | ||
|  | 
 | ||
|  |     /* Now that context has been saved, we can use other registers */ | ||
|  | 
 | ||
|  |     /* Restore vcpu */ | ||
|  |     mfc0        a1, CP0_DDATA_LO | ||
|  |     move        s1, a1 | ||
|  | 
 | ||
|  |    /* Restore run (vcpu->run) */ | ||
|  |     LONG_L      a0, VCPU_RUN(a1) | ||
|  |     /* Save pointer to run in s0, will be saved by the compiler */ | ||
|  |     move        s0, a0 | ||
|  | 
 | ||
|  | 
 | ||
|  |     /* Save Host level EPC, BadVaddr and Cause to VCPU, useful to process the exception */ | ||
|  |     mfc0    k0,CP0_EPC | ||
|  |     LONG_S  k0, VCPU_PC(k1) | ||
|  | 
 | ||
|  |     mfc0    k0, CP0_BADVADDR | ||
|  |     LONG_S  k0, VCPU_HOST_CP0_BADVADDR(k1) | ||
|  | 
 | ||
|  |     mfc0    k0, CP0_CAUSE | ||
|  |     LONG_S  k0, VCPU_HOST_CP0_CAUSE(k1) | ||
|  | 
 | ||
|  |     mfc0    k0, CP0_ENTRYHI | ||
|  |     LONG_S  k0, VCPU_HOST_ENTRYHI(k1) | ||
|  | 
 | ||
|  |     /* Now restore the host state just enough to run the handlers */ | ||
|  | 
 | ||
|  |     /* Swtich EBASE to the one used by Linux */ | ||
|  |     /* load up the host EBASE */ | ||
|  |     mfc0        v0, CP0_STATUS | ||
|  | 
 | ||
|  |     .set at
 | ||
|  | 	or          k0, v0, ST0_BEV | ||
|  |     .set noat
 | ||
|  | 
 | ||
|  |     mtc0        k0, CP0_STATUS | ||
|  |     ehb | ||
|  | 
 | ||
|  |     LONG_L      k0, VCPU_HOST_EBASE(k1) | ||
|  |     mtc0        k0,CP0_EBASE | ||
|  | 
 | ||
|  | 
 | ||
|  |     /* Now that the new EBASE has been loaded, unset BEV and KSU_USER */ | ||
|  |     .set at
 | ||
|  | 	and         v0, v0, ~(ST0_EXL | KSU_USER | ST0_IE) | ||
|  |     or          v0, v0, ST0_CU0 | ||
|  |     .set noat
 | ||
|  |     mtc0        v0, CP0_STATUS | ||
|  |     ehb | ||
|  | 
 | ||
|  |     /* Load up host GP */ | ||
|  |     LONG_L  gp, VCPU_HOST_GP(k1) | ||
|  | 
 | ||
|  |     /* Need a stack before we can jump to "C" */ | ||
|  |     LONG_L  sp, VCPU_HOST_STACK(k1) | ||
|  | 
 | ||
|  |     /* Saved host state */ | ||
|  |     addiu   sp,sp, -PT_SIZE | ||
|  | 
 | ||
|  |     /* XXXKYMA do we need to load the host ASID, maybe not because the | ||
|  |      * kernel entries are marked GLOBAL, need to verify | ||
|  |      */ | ||
|  | 
 | ||
|  |     /* Restore host DDATA_LO */ | ||
|  |     LONG_L      k0, PT_HOST_USERLOCAL(sp) | ||
|  |     mtc0        k0, CP0_DDATA_LO | ||
|  | 
 | ||
|  |     /* Restore RDHWR access */ | ||
|  |     la      k0, 0x2000000F | ||
|  |     mtc0    k0,  CP0_HWRENA | ||
|  | 
 | ||
|  |     /* Jump to handler */ | ||
|  | FEXPORT(__kvm_mips_jump_to_handler) | ||
|  |     /* XXXKYMA: not sure if this is safe, how large is the stack?? */ | ||
|  |     /* Now jump to the kvm_mips_handle_exit() to see if we can deal with this in the kernel */ | ||
|  |     la          t9,kvm_mips_handle_exit | ||
|  |     jalr.hb     t9 | ||
|  |     addiu       sp,sp, -CALLFRAME_SIZ           /* BD Slot */ | ||
|  | 
 | ||
|  |     /* Return from handler Make sure interrupts are disabled */ | ||
|  |     di | ||
|  |     ehb | ||
|  | 
 | ||
|  |     /* XXXKYMA: k0/k1 could have been blown away if we processed an exception | ||
|  |      * while we were handling the exception from the guest, reload k1 | ||
|  |      */ | ||
|  |     move        k1, s1 | ||
|  | 	addiu		k1, k1, VCPU_HOST_ARCH | ||
|  | 
 | ||
|  |     /* Check return value, should tell us if we are returning to the host (handle I/O etc) | ||
|  |      * or resuming the guest | ||
|  |      */ | ||
|  |     andi        t0, v0, RESUME_HOST | ||
|  |     bnez        t0, __kvm_mips_return_to_host | ||
|  |     nop | ||
|  | 
 | ||
|  | __kvm_mips_return_to_guest: | ||
|  |     /* Put the saved pointer to vcpu (s1) back into the DDATA_LO Register */ | ||
|  |     mtc0        s1, CP0_DDATA_LO | ||
|  | 
 | ||
|  |     /* Load up the Guest EBASE to minimize the window where BEV is set */ | ||
|  |     LONG_L      t0, VCPU_GUEST_EBASE(k1) | ||
|  | 
 | ||
|  |     /* Switch EBASE back to the one used by KVM */ | ||
|  |     mfc0        v1, CP0_STATUS | ||
|  |     .set at
 | ||
|  | 	or          k0, v1, ST0_BEV | ||
|  |     .set noat
 | ||
|  |     mtc0        k0, CP0_STATUS | ||
|  |     ehb | ||
|  |     mtc0        t0,CP0_EBASE | ||
|  | 
 | ||
|  |     /* Setup status register for running guest in UM */ | ||
|  |     .set at
 | ||
|  |     or     v1, v1, (ST0_EXL | KSU_USER | ST0_IE) | ||
|  |     and     v1, v1, ~ST0_CU0 | ||
|  |     .set noat
 | ||
|  |     mtc0    v1, CP0_STATUS | ||
|  |     ehb | ||
|  | 
 | ||
|  | 
 | ||
|  | 	/* Set Guest EPC */ | ||
|  | 	LONG_L		t0, VCPU_PC(k1) | ||
|  | 	mtc0		t0, CP0_EPC | ||
|  | 
 | ||
|  |     /* Set the ASID for the Guest Kernel */ | ||
|  |     sll         t0, t0, 1                       /* with kseg0 @ 0x40000000, kernel */
 | ||
|  |                                                 /* addresses shift to 0x80000000 */ | ||
|  |     bltz        t0, 1f                          /* If kernel */ | ||
|  | 	addiu       t1, k1, VCPU_GUEST_KERNEL_ASID  /* (BD)  */ | ||
|  |     addiu       t1, k1, VCPU_GUEST_USER_ASID    /* else user */ | ||
|  | 1: | ||
|  |     /* t1: contains the base of the ASID array, need to get the cpu id  */ | ||
|  |     LONG_L      t2, TI_CPU($28)             /* smp_processor_id */ | ||
|  |     sll         t2, t2, 2                   /* x4 */ | ||
|  |     addu        t3, t1, t2 | ||
|  |     LONG_L      k0, (t3) | ||
|  |     andi        k0, k0, 0xff | ||
|  | 	mtc0		k0,CP0_ENTRYHI | ||
|  |     ehb | ||
|  | 
 | ||
|  |     /* Disable RDHWR access */ | ||
|  |     mtc0    zero,  CP0_HWRENA | ||
|  | 
 | ||
|  |     /* load the guest context from VCPU and return */ | ||
|  |     LONG_L  $0, VCPU_R0(k1) | ||
|  |     LONG_L  $1, VCPU_R1(k1) | ||
|  |     LONG_L  $2, VCPU_R2(k1) | ||
|  |     LONG_L  $3, VCPU_R3(k1) | ||
|  |     LONG_L  $4, VCPU_R4(k1) | ||
|  |     LONG_L  $5, VCPU_R5(k1) | ||
|  |     LONG_L  $6, VCPU_R6(k1) | ||
|  |     LONG_L  $7, VCPU_R7(k1) | ||
|  |     LONG_L  $8, VCPU_R8(k1) | ||
|  |     LONG_L  $9, VCPU_R9(k1) | ||
|  |     LONG_L  $10, VCPU_R10(k1) | ||
|  |     LONG_L  $11, VCPU_R11(k1) | ||
|  |     LONG_L  $12, VCPU_R12(k1) | ||
|  |     LONG_L  $13, VCPU_R13(k1) | ||
|  |     LONG_L  $14, VCPU_R14(k1) | ||
|  |     LONG_L  $15, VCPU_R15(k1) | ||
|  |     LONG_L  $16, VCPU_R16(k1) | ||
|  |     LONG_L  $17, VCPU_R17(k1) | ||
|  |     LONG_L  $18, VCPU_R18(k1) | ||
|  |     LONG_L  $19, VCPU_R19(k1) | ||
|  |     LONG_L  $20, VCPU_R20(k1) | ||
|  |     LONG_L  $21, VCPU_R21(k1) | ||
|  |     LONG_L  $22, VCPU_R22(k1) | ||
|  |     LONG_L  $23, VCPU_R23(k1) | ||
|  |     LONG_L  $24, VCPU_R24(k1) | ||
|  |     LONG_L  $25, VCPU_R25(k1) | ||
|  | 
 | ||
|  |     /* $/k1 loaded later */ | ||
|  |     LONG_L  $28, VCPU_R28(k1) | ||
|  |     LONG_L  $29, VCPU_R29(k1) | ||
|  |     LONG_L  $30, VCPU_R30(k1) | ||
|  |     LONG_L  $31, VCPU_R31(k1) | ||
|  | 
 | ||
|  | FEXPORT(__kvm_mips_skip_guest_restore) | ||
|  |     LONG_L  k0, VCPU_HI(k1) | ||
|  |     mthi    k0 | ||
|  | 
 | ||
|  |     LONG_L  k0, VCPU_LO(k1) | ||
|  |     mtlo    k0 | ||
|  | 
 | ||
|  |     LONG_L  k0, VCPU_R26(k1) | ||
|  |     LONG_L  k1, VCPU_R27(k1) | ||
|  | 
 | ||
|  |     eret | ||
|  | 
 | ||
|  | __kvm_mips_return_to_host: | ||
|  |     /* EBASE is already pointing to Linux */ | ||
|  |     LONG_L  k1, VCPU_HOST_STACK(k1) | ||
|  | 	addiu  	k1,k1, -PT_SIZE | ||
|  | 
 | ||
|  |     /* Restore host DDATA_LO */ | ||
|  |     LONG_L      k0, PT_HOST_USERLOCAL(k1) | ||
|  |     mtc0        k0, CP0_DDATA_LO | ||
|  | 
 | ||
|  |     /* Restore host ASID */ | ||
|  |     LONG_L      k0, PT_HOST_ASID(sp) | ||
|  |     andi        k0, 0xff | ||
|  |     mtc0        k0,CP0_ENTRYHI | ||
|  |     ehb | ||
|  | 
 | ||
|  |     /* Load context saved on the host stack */ | ||
|  |     LONG_L  $0, PT_R0(k1) | ||
|  |     LONG_L  $1, PT_R1(k1) | ||
|  | 
 | ||
|  |     /* r2/v0 is the return code, shift it down by 2 (arithmetic) to recover the err code  */ | ||
|  |     sra     k0, v0, 2 | ||
|  |     move    $2, k0 | ||
|  | 
 | ||
|  |     LONG_L  $3, PT_R3(k1) | ||
|  |     LONG_L  $4, PT_R4(k1) | ||
|  |     LONG_L  $5, PT_R5(k1) | ||
|  |     LONG_L  $6, PT_R6(k1) | ||
|  |     LONG_L  $7, PT_R7(k1) | ||
|  |     LONG_L  $8, PT_R8(k1) | ||
|  |     LONG_L  $9, PT_R9(k1) | ||
|  |     LONG_L  $10, PT_R10(k1) | ||
|  |     LONG_L  $11, PT_R11(k1) | ||
|  |     LONG_L  $12, PT_R12(k1) | ||
|  |     LONG_L  $13, PT_R13(k1) | ||
|  |     LONG_L  $14, PT_R14(k1) | ||
|  |     LONG_L  $15, PT_R15(k1) | ||
|  |     LONG_L  $16, PT_R16(k1) | ||
|  |     LONG_L  $17, PT_R17(k1) | ||
|  |     LONG_L  $18, PT_R18(k1) | ||
|  |     LONG_L  $19, PT_R19(k1) | ||
|  |     LONG_L  $20, PT_R20(k1) | ||
|  |     LONG_L  $21, PT_R21(k1) | ||
|  |     LONG_L  $22, PT_R22(k1) | ||
|  |     LONG_L  $23, PT_R23(k1) | ||
|  |     LONG_L  $24, PT_R24(k1) | ||
|  |     LONG_L  $25, PT_R25(k1) | ||
|  | 
 | ||
|  |     /* Host k0/k1 were not saved */ | ||
|  | 
 | ||
|  |     LONG_L  $28, PT_R28(k1) | ||
|  |     LONG_L  $29, PT_R29(k1) | ||
|  |     LONG_L  $30, PT_R30(k1) | ||
|  | 
 | ||
|  |     LONG_L  k0, PT_HI(k1) | ||
|  |     mthi    k0 | ||
|  | 
 | ||
|  |     LONG_L  k0, PT_LO(k1) | ||
|  |     mtlo    k0 | ||
|  | 
 | ||
|  |     /* Restore RDHWR access */ | ||
|  |     la      k0, 0x2000000F | ||
|  |     mtc0    k0,  CP0_HWRENA | ||
|  | 
 | ||
|  | 
 | ||
|  |     /* Restore RA, which is the address we will return to */ | ||
|  |     LONG_L  ra, PT_R31(k1) | ||
|  |     j       ra | ||
|  |     nop | ||
|  | 
 | ||
|  |     .set    pop
 | ||
|  | VECTOR_END(MIPSX(GuestExceptionEnd)) | ||
|  | .end MIPSX(GuestException) | ||
|  | 
 | ||
|  | MIPSX(exceptions): | ||
|  | 	#### | ||
|  | 	##### The exception handlers. | ||
|  | 	##### | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  0 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  1 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  2 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  3 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  4 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  5 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  6 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  7 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  8 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	#  9 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 10 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 11 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 12 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 13 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 14 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 15 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 16 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 17 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 18 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 19 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 20 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 21 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 22 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 23 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 24 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 25 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 26 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 27 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 28 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 29 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 30 | ||
|  | 	.word _C_LABEL(MIPSX(GuestException))	# 31 | ||
|  | 
 | ||
|  | 
 | ||
|  | /* This routine makes changes to the instruction stream effective to the hardware. | ||
|  |  * It should be called after the instruction stream is written. | ||
|  |  * On return, the new instructions are effective. | ||
|  |  * Inputs: | ||
|  |  * a0 = Start address of new instruction stream | ||
|  |  * a1 = Size, in bytes, of new instruction stream | ||
|  |  */ | ||
|  | 
 | ||
|  | #define HW_SYNCI_Step       $1 | ||
|  | LEAF(MIPSX(SyncICache)) | ||
|  |     .set    push
 | ||
|  | 	.set	mips32r2
 | ||
|  |     beq     a1, zero, 20f | ||
|  |     nop | ||
|  |     addu    a1, a0, a1 | ||
|  |     rdhwr   v0, HW_SYNCI_Step | ||
|  |     beq     v0, zero, 20f | ||
|  |     nop | ||
|  | 
 | ||
|  | 10: | ||
|  |     synci   0(a0) | ||
|  |     addu    a0, a0, v0 | ||
|  |     sltu    v1, a0, a1 | ||
|  |     bne     v1, zero, 10b | ||
|  |     nop | ||
|  |     sync | ||
|  | 20: | ||
|  |     jr.hb   ra | ||
|  |     nop | ||
|  |     .set pop
 | ||
|  | END(MIPSX(SyncICache)) |