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/* Shared definitions for supervisor-mode page-table-entries and permission checks.
*
* These definitions are independent of xlen and do not involve
* accessing physical memory.
*/
/* PageSize */
let PAGESIZE_BITS = 12
/*
* Definitions for RV32, which has a single address translation mode: Sv32.
*/
type vaddr32 = bits(32)
type paddr32 = bits(34)
type pte32 = bits(32)
/* asid */
type asid32 = bits(9)
function curAsid32(satp : bits(32)) -> asid32 = {
let s = Mk_Satp32(satp);
s.Asid()
}
/* page table base from satp */
function curPTB32(satp : bits(32)) -> paddr32 = {
let s : Satp32 = Mk_Satp32(satp);
shiftl(EXTZ(s.PPN()), PAGESIZE_BITS)
}
/* Sv32 parameters and bitfield layouts */
let SV32_LEVEL_BITS = 10
let SV32_LEVELS = 2
let PTE32_LOG_SIZE = 2
let PTE32_SIZE = 4
bitfield SV32_Vaddr : vaddr32 = {
VPNi : 31 .. 12,
PgOfs : 11 .. 0
}
bitfield SV32_Paddr : paddr32 = {
PPNi : 33 .. 12,
PgOfs : 11 .. 0
}
bitfield SV32_PTE : pte32 = {
PPNi : 31 .. 10,
RSW : 9 .. 8,
BITS : 7 .. 0
}
/*
* Definitions for RV64, which has two defined address translation modes: Sv39 and Sv48.
*/
/* Sv48 and Sv64 are reserved but not defined. The size of the VPN
* increases by 9 bits through Sv39, Sv48 and Sv57, but not for Sv64.
* Also, the 45-bit size of the VPN for Sv57 exceeds the 44-bit size
* of the PPN in satp64. Due to these corner cases, it is unlikely
* that definitions can be shared across all four schemes, so separate
* definitions might eventually be needed for each translation mode.
*
* But to keep things simple for now, since Sv39 and Sv48 have the
* same PPN size, we share some definitions.
*/
type paddr64 = bits(56)
type pte64 = bits(64)
/* asid */
type asid64 = bits(16)
function curAsid64(satp : bits(64)) -> asid64 = {
let s = Mk_Satp64(satp);
s.Asid()
}
/* page table base from satp */
function curPTB64(satp : bits(64)) -> paddr64 = {
let s = Mk_Satp64(satp);
shiftl(EXTZ(s.PPN()), PAGESIZE_BITS)
}
/* Sv39 parameters and bitfield layouts */
let SV39_LEVEL_BITS = 9
let SV39_LEVELS = 3
let PTE39_LOG_SIZE = 3
let PTE39_SIZE = 8
type vaddr39 = bits(39)
bitfield SV39_Vaddr : vaddr39 = {
VPNi : 38 .. 12,
PgOfs : 11 .. 0
}
bitfield SV39_Paddr : paddr64 = {
PPNi : 55 .. 12,
PgOfs : 11 .. 0
}
bitfield SV39_PTE : pte64 = {
Ext : 63 .. 54,
PPNi : 53 .. 10,
RSW : 9 .. 8,
BITS : 7 .. 0
}
/* Sv48 parameters and bitfield layouts */
let SV48_LEVEL_BITS = 9
let SV48_LEVELS = 4
let PTE48_LOG_SIZE = 3
let PTE48_SIZE = 8
type vaddr48 = bits(48)
type pte48 = bits(64)
bitfield SV48_Vaddr : vaddr48 = {
VPNi : 38 .. 12,
PgOfs : 11 .. 0
}
bitfield SV48_Paddr : paddr64 = {
PPNi : 55 .. 12,
PgOfs : 11 .. 0
}
bitfield SV48_PTE : pte48 = {
Ext : 63 .. 54,
PPNi : 53 .. 10,
RSW : 9 .. 8,
BITS : 7 .. 0
}
/* The types below are parameterized by 'paddr and 'pte to support
* various architectural widths (e.g. RV32, RV64). ext_ptw supports
* extensions to the default address translation and page-table-walk.
*/
/* Result of a page-table walk. */
union PTW_Result('paddr : Type, 'pte : Type) = {
PTW_Success: ('paddr, 'pte, 'paddr, nat, bool, ext_ptw),
PTW_Failure: (PTW_Error, ext_ptw)
}
/* Result of address translation */
union TR_Result('paddr : Type, 'failure : Type) = {
TR_Address : ('paddr, ext_ptw),
TR_Failure : ('failure, ext_ptw)
}
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