///////////////////////////////////////////
// tlbNAPOT.S
//
// Written: mmendozamanriquez@hmc.edu 4 April 2023
// nlimpert@hmc.edu
// Adapted David_Harris@hmc.edu 8/29/23 to exercise NAPOT huge pages
//
// Purpose: Test coverage for LSU NAPOT
//
// A component of the CORE-V-WALLY configurable RISC-V project.
// https://github.com/openhwgroup/cvw
//
// Copyright (C) 2021-23 Harvey Mudd College & Oklahoma State University
//
// SPDX-License-Identifier: Apache-2.0 WITH SHL-2.1
//
// Licensed under the Solderpad Hardware License v 2.1 (the “License”); you may not use this file
// except in compliance with the License, or, at your option, the Apache License version 2.0. You
// may obtain a copy of the License at
//
// https://solderpad.org/licenses/SHL-2.1/
//
// Unless required by applicable law or agreed to in writing, any work distributed under the
// License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
// either express or implied. See the License for the specific language governing permissions
// and limitations under the License.
////////////////////////////////////////////////////////////////////////////////////////////////
// load code to initalize stack, handle interrupts, terminate
#include "WALLY-init-lib.h"
# run-elf.bash find this in project description
main:
li t5, 0x1
slli t5, t5, 62
csrs menvcfg, t5
# Page table root address at 0x80010000; SV48
li t5, 0x9000000000080010
csrw satp, t5
# sfence.vma x0, x0
# switch to supervisor mode
li a0, 1
ecall
li t4, 0x200000 # address step size
li a2, 0x80215240 # Test NAPOT pages
jal a1, looptest
li a2, 0xC0215240 # Test ill-formed NAPOT pages
jal a1, looptest
li a2, 0x40215240 # Test properly formed pages with 1 in PPN[3] that are not NAPOT
jal a1, looptest
li t4, 0x1000 # address step size
li a2, 0x80216000 # Test NAPOT pages
jal a1, looptest
sfence.vma
li t4, 0x200000 # address step size
li a2, 0x80215240 # Test NAPOT pages
jal a1, looptest
li a2, 0xC0215240 # Test ill-formed NAPOT pages
jal a1, looptest
li a2, 0x40215240 # Test properly formed pages with 1 in PPN[3] that are not NAPOT
jal a1, looptest
li a0, 3 # switch back to machine mode because code at 0x80000000 may not have clean page table entry
ecall
j done
looptest:
mv t0, a2 # base address
li t2, 0 # i = 0
li t3, 32 # Max amount of Loops = 32
li t5, 0x8082 # return instruction opcode
loop: bge t2, t3, finished # exit loop if i >= loops
sw t5, 0(t0) # store a return at this address to exercise DTLB
lw t1, 0(t0) # read it back
fence.i # synchronize with I$
jal changetoipfhandler # set up trap handler to return from instruction page fault if necessary
jalr ra, t0 # jump to the return statement to exercise the ITLB
jal changetodefaulthandler
add t0, t0, t4
addi t2, t2, 1
j loop
finished:
jr a1
changetoipfhandler:
li a0, 3
ecall # switch to machine mode
la a0, ipf_handler
csrw mtvec, a0 # point to new handler
li a0, 1
ecall # switch back to supervisor mode
ret
changetodefaulthandler:
li a0, 3
ecall # switch to machine mode
la a0, trap_handler
csrw mtvec, a0 # point to new handler
li a0, 1
ecall # switch back to supervisor mode
ret
instructionpagefaulthandler:
csrw mepc, ra # go back to calling function
mret
.align 4 # trap handlers must be aligned to multiple of 4
ipf_handler:
# Load trap handler stack pointer tp
csrrw tp, mscratch, tp # swap MSCRATCH and tp
sd t0, 0(tp) # Save t0 and t1 on the stack
sd t1, -8(tp)
csrr t0, mcause # Check the cause
li t1, 8 # is it an ecall trap?
andi t0, t0, 0xFC # if CAUSE = 8, 9, or 11
beq t0, t1, ecall # yes, take ecall
csrr t0, mcause
li t1, 12 # is it an instruction page fault
beq t0, t1, ipf # yes, return to calling function
j trap_return
ipf:
csrw mepc, ra # return to calling function
ld t1, -8(tp) # restore t1 and t0
ld t0, 0(tp)
csrrw tp, mscratch, tp # restore tp
mret # return from trap
.data
.align 16
# root Page table situated at 0x80010000
pagetable:
.8byte 0x200044C1 // old page table was 200040 which just pointed to itself! wrong
# next page table at 0x80011000
.align 12
.8byte 0x0000000000000000 # gigapage at 0x00000000
.8byte 0x00000000200058C1 # gigapage at 0x40000000 used for non-NAPOT with PPN bit 3 set
.8byte 0x00000000200048C1 # gigapage at 0x80000000 used for testing NAPOT huge pages
.8byte 0x00000000200050C1 # gigapage at 0xC0000000 mapped to ill-formed NAPOT with wrong PPN
# Next page table at 0x80012000 for gigapage at 0x80000000
.align 12
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
.8byte 0x0000000020004CC1
# Leaf page table at 0x80013000 with NAPOT pages
.align 12
#80000000
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0xA0000000200020CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x80000000200060CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000A0CF
.8byte 0x800000002000E0CF
.8byte 0x800000002000E0CF
.8byte 0x800000002000E0CF
.8byte 0x800000002000E0CF
.8byte 0x800000002000E0CF
.8byte 0x800000002000E0CF
# Next page table at 0x80014000: mega-sized, pointing to malformed NAPOT for gigapage at 0xC9000000
.align 12
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
.8byte 0x00000000200054C1
# Leaf page table at 0x80015000 with malformed NAPOT pages (wrong PPN) starting at 0xC0000000
.align 12
#80000000
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
.8byte 0x80000000200000CF
# Next page table at 0x80016000: mega-sized, pointing to properly formed PTE with 1 in PPN bit 3 for gigapage at 0x40000000
.align 12
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
.8byte 0x0000000020005CC1
# Leaf page table at 0x80017000 with properly formed PTE with bit 4 of PPN set but no NAPOT
.align 12
#80000000
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF
.8byte 0x00000000200020CF
.8byte 0x00000000200060CF
.8byte 0x000000002000A0CF
.8byte 0x000000002000E0CF