nextpnr/nexus/arch.h

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/*
* nextpnr -- Next Generation Place and Route
*
* Copyright (C) 2020 gatecat <gatecat@ds0.me>
*
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#ifndef NEXUS_ARCH_H
#define NEXUS_ARCH_H
#include <boost/iostreams/device/mapped_file.hpp>
#include <iostream>
#include "base_arch.h"
#include "nextpnr_namespaces.h"
#include "nextpnr_types.h"
#include "relptr.h"
NEXTPNR_NAMESPACE_BEGIN
/*
Fully deduplicated database
There are two key data structures in the database:
Locations (aka tile but not called this to avoid confusion
with Lattice terminology), are a (x, y) location.
Local wires; pips and bels are all stored once per variety of location
(called a location type) with a separate grid containing the location type
at a (x, y) coordinate.
Each location also has _neighbours_, other locations with interconnected
wires. The set of neighbours for a location are called a _neighbourhood_.
Each variety of _neighbourhood_ for a location type is also stored once,
using relative coordinates.
*/
NPNR_PACKED_STRUCT(struct BelWirePOD {
uint32_t port;
uint16_t type;
uint16_t wire_index; // wire index in tile
});
NPNR_PACKED_STRUCT(struct BelInfoPOD {
int32_t name; // bel name in tile IdString
int32_t type; // bel type IdString
int16_t rel_x, rel_y; // bel location relative to parent
int32_t z; // bel location absolute Z
RelSlice<BelWirePOD> ports; // ports, sorted by name IdString
});
NPNR_PACKED_STRUCT(struct BelPinPOD {
uint32_t bel; // bel index in tile
int32_t pin; // bel pin name IdString
});
enum TileWireFlags : uint32_t
{
WIRE_PRIMARY = 0x80000000,
};
NPNR_PACKED_STRUCT(struct LocWireInfoPOD {
int32_t name; // wire name in tile IdString
uint32_t flags;
// Note this pip lists exclude neighbourhood pips
RelSlice<int32_t> pips_uh, pips_dh; // list of uphill/downhill pip indices in tile
RelSlice<BelPinPOD> bel_pins;
});
enum PipFlags
{
PIP_FIXED_CONN = 0x8000,
PIP_LUT_PERM = 0x4000,
PIP_ZERO_RR_COST = 0x2000,
PIP_DRMUX_C = 0x1000,
};
NPNR_PACKED_STRUCT(struct PipInfoPOD {
uint16_t from_wire, to_wire;
uint16_t flags;
uint16_t timing_class;
int32_t tile_type;
});
enum RelLocType : uint8_t
{
REL_LOC_XY = 0,
REL_LOC_GLOBAL = 1,
REL_LOC_BRANCH = 2,
REL_LOC_BRANCH_L = 3,
REL_LOC_BRANCH_R = 4,
REL_LOC_SPINE = 5,
REL_LOC_HROW = 6,
REL_LOC_VCC = 7,
};
enum ArcFlags
{
LOGICAL_TO_PRIMARY = 0x80,
PHYSICAL_DOWNHILL = 0x08,
};
NPNR_PACKED_STRUCT(struct RelWireInfoPOD {
int16_t rel_x, rel_y;
uint16_t wire_index;
uint8_t loc_type;
uint8_t arc_flags;
});
NPNR_PACKED_STRUCT(struct WireNeighboursInfoPOD { RelSlice<RelWireInfoPOD> neigh_wires; });
NPNR_PACKED_STRUCT(struct LocNeighourhoodPOD { RelSlice<WireNeighboursInfoPOD> wire_neighbours; });
NPNR_PACKED_STRUCT(struct LocTypePOD {
RelSlice<BelInfoPOD> bels;
RelSlice<LocWireInfoPOD> wires;
RelSlice<PipInfoPOD> pips;
RelSlice<LocNeighourhoodPOD> neighbourhoods;
});
// A physical (bitstream) tile; of which there may be more than
// one in a logical tile (XY grid location).
// Tile name is reconstructed {prefix}R{row}C{col}:{tiletype}
NPNR_PACKED_STRUCT(struct PhysicalTileInfoPOD {
int32_t prefix; // tile name prefix IdString
int32_t tiletype; // tile type IdString
});
enum LocFlags : uint32_t
{
LOC_LOGIC = 0x000001,
LOC_IO18 = 0x000002,
LOC_IO33 = 0x000004,
LOC_BRAM = 0x000008,
LOC_DSP = 0x000010,
LOC_IP = 0x000020,
LOC_CIB = 0x000040,
LOC_TAP = 0x001000,
LOC_SPINE = 0x002000,
LOC_TRUNK = 0x004000,
LOC_MIDMUX = 0x008000,
LOC_CMUX = 0x010000,
};
NPNR_PACKED_STRUCT(struct GridLocationPOD {
uint32_t loc_type;
uint32_t loc_flags;
uint16_t neighbourhood_type;
uint16_t padding;
RelSlice<PhysicalTileInfoPOD> phys_tiles;
});
enum PioSide : uint8_t
{
PIO_LEFT = 0,
PIO_RIGHT = 1,
PIO_TOP = 2,
PIO_BOTTOM = 3
};
enum PioDqsFunction : uint8_t
{
PIO_DQS_DQ = 0,
PIO_DQS_DQS = 1,
PIO_DQS_DQSN = 2
};
NPNR_PACKED_STRUCT(struct PackageInfoPOD {
RelPtr<char> full_name; // full package name, e.g. CABGA400
RelPtr<char> short_name; // name used in part number, e.g. BG400
});
NPNR_PACKED_STRUCT(struct PadInfoPOD {
int16_t offset; // position offset of tile along side (-1 if not a regular PIO)
int8_t side; // PIO side (see PioSide enum)
int8_t pio_index; // index within IO tile
int16_t bank; // IO bank
int16_t dqs_group; // DQS group offset
int8_t dqs_func; // DQS function
int8_t vref_index; // VREF index in bank, or -1 if N/A
int16_t padding;
RelSlice<uint32_t> func_strs; // list of special function IdStrings
RelSlice<RelPtr<char>> pins; // package index --> package pin name
});
NPNR_PACKED_STRUCT(struct GlobalBranchInfoPOD {
uint16_t branch_col;
uint16_t from_col;
uint16_t tap_driver_col;
uint16_t tap_side;
uint16_t to_col;
uint16_t padding;
});
NPNR_PACKED_STRUCT(struct GlobalSpineInfoPOD {
uint16_t from_row;
uint16_t to_row;
uint16_t spine_row;
uint16_t padding;
});
NPNR_PACKED_STRUCT(struct GlobalHrowInfoPOD {
uint16_t hrow_col;
uint16_t padding;
RelSlice<uint32_t> spine_cols;
});
NPNR_PACKED_STRUCT(struct GlobalInfoPOD {
RelSlice<GlobalBranchInfoPOD> branches;
RelSlice<GlobalSpineInfoPOD> spines;
RelSlice<GlobalHrowInfoPOD> hrows;
});
NPNR_PACKED_STRUCT(struct ChipInfoPOD {
RelPtr<char> device_name;
uint16_t width;
uint16_t height;
RelSlice<GridLocationPOD> grid;
RelPtr<GlobalInfoPOD> globals;
RelSlice<PadInfoPOD> pads;
RelSlice<PackageInfoPOD> packages;
});
NPNR_PACKED_STRUCT(struct IdStringDBPOD {
uint32_t num_file_ids;
RelSlice<RelPtr<char>> bba_id_strs;
});
// Timing structures are generally sorted using IdString indices as keys for fast binary searches
// All delays are integer picoseconds
// Sort key: (to_port, from_port) for binary search by IdString
NPNR_PACKED_STRUCT(struct CellPropDelayPOD {
int32_t from_port;
int32_t to_port;
int32_t min_delay;
int32_t max_delay;
});
// Sort key: (sig_port, clock_port) for binary search by IdString
NPNR_PACKED_STRUCT(struct CellSetupHoldPOD {
int32_t sig_port;
int32_t clock_port;
int32_t min_setup;
int32_t max_setup;
int32_t min_hold;
int32_t max_hold;
});
// Sort key: (cell_type, cell_variant) for binary search by IdString
NPNR_PACKED_STRUCT(struct CellTimingPOD {
int32_t cell_type;
int32_t cell_variant;
RelSlice<CellPropDelayPOD> prop_delays;
RelSlice<CellSetupHoldPOD> setup_holds;
});
NPNR_PACKED_STRUCT(struct PipTimingPOD {
int32_t min_delay;
int32_t max_delay;
// fanout adder seemingly unused by nexus, reserved for future ECP5 etc support
int32_t min_fanout_adder;
int32_t max_fanout_adder;
});
NPNR_PACKED_STRUCT(struct SpeedGradePOD {
RelPtr<char> name;
RelSlice<CellTimingPOD> cell_types;
RelSlice<PipTimingPOD> pip_classes;
});
NPNR_PACKED_STRUCT(struct DatabasePOD {
uint32_t version;
RelPtr<char> family;
RelSlice<ChipInfoPOD> chips;
RelSlice<LocTypePOD> loctypes;
RelSlice<SpeedGradePOD> speed_grades;
RelPtr<IdStringDBPOD> ids;
});
// -----------------------------------------------------------------------
// Helper functions for database access
namespace {
template <typename Id> const LocTypePOD &chip_loc_data(const DatabasePOD *db, const ChipInfoPOD *chip, const Id &id)
{
return db->loctypes[chip->grid[id.tile].loc_type];
}
template <typename Id>
const LocNeighourhoodPOD &chip_nh_data(const DatabasePOD *db, const ChipInfoPOD *chip, const Id &id)
{
auto &t = chip->grid[id.tile];
return db->loctypes[t.loc_type].neighbourhoods[t.neighbourhood_type];
}
inline const BelInfoPOD &chip_bel_data(const DatabasePOD *db, const ChipInfoPOD *chip, BelId id)
{
return chip_loc_data(db, chip, id).bels[id.index];
}
inline const LocWireInfoPOD &chip_wire_data(const DatabasePOD *db, const ChipInfoPOD *chip, WireId id)
{
return chip_loc_data(db, chip, id).wires[id.index];
}
inline const PipInfoPOD &chip_pip_data(const DatabasePOD *db, const ChipInfoPOD *chip, PipId id)
{
return chip_loc_data(db, chip, id).pips[id.index];
}
inline bool chip_rel_tile(const ChipInfoPOD *chip, int32_t base, int16_t rel_x, int16_t rel_y, int32_t &next)
{
int32_t curr_x = base % chip->width;
int32_t curr_y = base / chip->width;
int32_t new_x = curr_x + rel_x;
int32_t new_y = curr_y + rel_y;
if (new_x < 0 || new_x >= chip->width)
return false;
if (new_y < 0 || new_y >= chip->height)
return false;
next = new_y * chip->width + new_x;
return true;
}
inline int32_t chip_tile_from_xy(const ChipInfoPOD *chip, int32_t x, int32_t y) { return y * chip->width + x; }
inline bool chip_get_branch_loc(const ChipInfoPOD *chip, int32_t x, int32_t &branch_x)
{
for (auto &b : chip->globals->branches) {
if (x >= b.from_col && x <= b.to_col) {
branch_x = b.branch_col;
return true;
}
}
return false;
}
inline bool chip_get_spine_loc(const ChipInfoPOD *chip, int32_t x, int32_t y, int32_t &spine_x, int32_t &spine_y)
{
bool y_found = false;
for (auto &s : chip->globals->spines) {
if (y >= s.from_row && y <= s.to_row) {
spine_y = s.spine_row;
y_found = true;
break;
}
}
if (!y_found)
return false;
for (auto &hr : chip->globals->hrows) {
for (int32_t sc : hr.spine_cols) {
if (std::abs(sc - x) < 3) {
spine_x = sc;
return true;
}
}
}
return false;
}
inline bool chip_get_hrow_loc(const ChipInfoPOD *chip, int32_t x, int32_t y, int32_t &hrow_x, int32_t &hrow_y)
{
bool y_found = false;
for (auto &s : chip->globals->spines) {
if (std::abs(y - s.spine_row) <= 3) {
hrow_y = s.spine_row;
y_found = true;
break;
}
}
if (!y_found)
return false;
for (auto &hr : chip->globals->hrows) {
for (int32_t sc : hr.spine_cols) {
if (std::abs(sc - x) < 3) {
hrow_x = hr.hrow_col;
return true;
}
}
}
return false;
}
inline bool chip_branch_tile(const ChipInfoPOD *chip, int32_t x, int32_t y, int32_t &next)
{
int32_t branch_x;
if (!chip_get_branch_loc(chip, x, branch_x))
return false;
next = chip_tile_from_xy(chip, branch_x, y);
return true;
}
inline bool chip_rel_loc_tile(const ChipInfoPOD *chip, int32_t base, const RelWireInfoPOD &rel, int32_t &next)
{
int32_t curr_x = base % chip->width;
int32_t curr_y = base / chip->width;
switch (rel.loc_type) {
case REL_LOC_XY:
return chip_rel_tile(chip, base, rel.rel_x, rel.rel_y, next);
case REL_LOC_BRANCH:
return chip_branch_tile(chip, curr_x, curr_y, next);
case REL_LOC_BRANCH_L:
return chip_branch_tile(chip, curr_x - 2, curr_y, next);
case REL_LOC_BRANCH_R:
return chip_branch_tile(chip, curr_x + 2, curr_y, next);
case REL_LOC_SPINE: {
int32_t spine_x, spine_y;
if (!chip_get_spine_loc(chip, curr_x, curr_y, spine_x, spine_y))
return false;
next = chip_tile_from_xy(chip, spine_x, spine_y);
return true;
}
case REL_LOC_HROW: {
int32_t hrow_x, hrow_y;
if (!chip_get_hrow_loc(chip, curr_x, curr_y, hrow_x, hrow_y))
return false;
next = chip_tile_from_xy(chip, hrow_x, hrow_y);
return true;
}
case REL_LOC_GLOBAL:
case REL_LOC_VCC:
next = 0;
return true;
default:
return false;
}
}
inline WireId chip_canonical_wire(const DatabasePOD *db, const ChipInfoPOD *chip, int32_t tile, uint16_t index)
{
WireId wire{tile, index};
// `tile` is the primary location for the wire, so ID is already canonical
if (chip_wire_data(db, chip, wire).flags & WIRE_PRIMARY)
return wire;
// Not primary; find the primary location which forms the canonical ID
auto &nd = chip_nh_data(db, chip, wire);
auto &wn = nd.wire_neighbours[index];
for (auto &nw : wn.neigh_wires) {
if (nw.arc_flags & LOGICAL_TO_PRIMARY) {
if (chip_rel_loc_tile(chip, tile, nw, wire.tile)) {
wire.index = nw.wire_index;
break;
}
}
}
return wire;
}
inline bool chip_wire_is_primary(const DatabasePOD *db, const ChipInfoPOD *chip, int32_t tile, uint16_t index)
{
WireId wire{tile, index};
// `tile` is the primary location for the wire, so ID is already canonical
if (chip_wire_data(db, chip, wire).flags & WIRE_PRIMARY)
return true;
// Not primary; find the primary location which forms the canonical ID
auto &nd = chip_nh_data(db, chip, wire);
auto &wn = nd.wire_neighbours[index];
for (auto &nw : wn.neigh_wires) {
if (nw.arc_flags & LOGICAL_TO_PRIMARY) {
if (chip_rel_loc_tile(chip, tile, nw, wire.tile)) {
return false;
}
}
}
return true;
}
} // namespace
// -----------------------------------------------------------------------
struct BelIterator
{
const DatabasePOD *db;
const ChipInfoPOD *chip;
int cursor_index;
int cursor_tile;
BelIterator operator++()
{
cursor_index++;
while (cursor_tile < chip->grid.ssize() &&
cursor_index >= db->loctypes[chip->grid[cursor_tile].loc_type].bels.ssize()) {
cursor_index = 0;
cursor_tile++;
}
return *this;
}
BelIterator operator++(int)
{
BelIterator prior(*this);
++(*this);
return prior;
}
bool operator!=(const BelIterator &other) const
{
return cursor_index != other.cursor_index || cursor_tile != other.cursor_tile;
}
bool operator==(const BelIterator &other) const
{
return cursor_index == other.cursor_index && cursor_tile == other.cursor_tile;
}
BelId operator*() const
{
BelId ret;
ret.tile = cursor_tile;
ret.index = cursor_index;
return ret;
}
};
struct BelRange
{
BelIterator b, e;
BelIterator begin() const { return b; }
BelIterator end() const { return e; }
};
// -----------------------------------------------------------------------
struct WireIterator
{
const DatabasePOD *db;
const ChipInfoPOD *chip;
int cursor_index;
int cursor_tile = 0;
WireIterator operator++()
{
// Iterate over nodes first, then tile wires that aren't nodes
do {
cursor_index++;
while (cursor_tile < chip->grid.ssize() &&
cursor_index >= db->loctypes[chip->grid[cursor_tile].loc_type].wires.ssize()) {
cursor_index = 0;
cursor_tile++;
}
} while (cursor_tile < chip->grid.ssize() && !chip_wire_is_primary(db, chip, cursor_tile, cursor_index));
return *this;
}
WireIterator operator++(int)
{
WireIterator prior(*this);
++(*this);
return prior;
}
bool operator!=(const WireIterator &other) const
{
return cursor_index != other.cursor_index || cursor_tile != other.cursor_tile;
}
bool operator==(const WireIterator &other) const
{
return cursor_index == other.cursor_index && cursor_tile == other.cursor_tile;
}
WireId operator*() const
{
WireId ret;
ret.tile = cursor_tile;
ret.index = cursor_index;
return ret;
}
};
struct WireRange
{
WireIterator b, e;
WireIterator begin() const { return b; }
WireIterator end() const { return e; }
};
// Iterate over all neighour wires for a wire
struct NeighWireIterator
{
const DatabasePOD *db;
const ChipInfoPOD *chip;
WireId baseWire;
int cursor = -1;
void operator++()
{
auto &wn = chip_nh_data(db, chip, baseWire).wire_neighbours[baseWire.index];
int32_t tile;
do
cursor++;
while (cursor < wn.neigh_wires.ssize() &&
((wn.neigh_wires[cursor].arc_flags & LOGICAL_TO_PRIMARY) ||
!chip_rel_tile(chip, baseWire.tile, wn.neigh_wires[cursor].rel_x, wn.neigh_wires[cursor].rel_y, tile)));
}
bool operator!=(const NeighWireIterator &other) const { return cursor != other.cursor; }
// Returns a *denormalised* identifier that may be a non-primary wire (and thus should _not_ be used
// as a WireId in general as it will break invariants)
WireId operator*() const
{
if (cursor == -1) {
return baseWire;
} else {
auto &nw = chip_nh_data(db, chip, baseWire).wire_neighbours[baseWire.index].neigh_wires[cursor];
WireId result;
result.index = nw.wire_index;
if (!chip_rel_tile(chip, baseWire.tile, nw.rel_x, nw.rel_y, result.tile))
return WireId();
return result;
}
}
};
struct NeighWireRange
{
NeighWireIterator b, e;
NeighWireIterator begin() const { return b; }
NeighWireIterator end() const { return e; }
};
// -----------------------------------------------------------------------
struct AllPipIterator
{
const DatabasePOD *db;
const ChipInfoPOD *chip;
int cursor_index;
int cursor_tile;
AllPipIterator operator++()
{
cursor_index++;
while (cursor_tile < chip->grid.ssize() &&
cursor_index >= db->loctypes[chip->grid[cursor_tile].loc_type].pips.ssize()) {
cursor_index = 0;
cursor_tile++;
}
return *this;
}
AllPipIterator operator++(int)
{
AllPipIterator prior(*this);
++(*this);
return prior;
}
bool operator!=(const AllPipIterator &other) const
{
return cursor_index != other.cursor_index || cursor_tile != other.cursor_tile;
}
bool operator==(const AllPipIterator &other) const
{
return cursor_index == other.cursor_index && cursor_tile == other.cursor_tile;
}
PipId operator*() const
{
PipId ret;
ret.tile = cursor_tile;
ret.index = cursor_index;
return ret;
}
};
struct AllPipRange
{
AllPipIterator b, e;
AllPipIterator begin() const { return b; }
AllPipIterator end() const { return e; }
};
// -----------------------------------------------------------------------
struct UpDownhillPipIterator
{
const DatabasePOD *db;
const ChipInfoPOD *chip;
NeighWireIterator twi, twi_end;
int cursor = -1;
bool uphill = false;
void operator++()
{
cursor++;
while (true) {
if (!(twi != twi_end))
break;
WireId w = *twi;
auto &tile = db->loctypes[chip->grid[w.tile].loc_type];
if (cursor < (uphill ? tile.wires[w.index].pips_uh.ssize() : tile.wires[w.index].pips_dh.ssize()))
break;
++twi;
cursor = 0;
}
}
bool operator!=(const UpDownhillPipIterator &other) const { return twi != other.twi || cursor != other.cursor; }
PipId operator*() const
{
PipId ret;
WireId w = *twi;
ret.tile = w.tile;
auto &tile = db->loctypes[chip->grid[w.tile].loc_type];
ret.index = uphill ? tile.wires[w.index].pips_uh[cursor] : tile.wires[w.index].pips_dh[cursor];
return ret;
}
};
struct UpDownhillPipRange
{
UpDownhillPipIterator b, e;
UpDownhillPipIterator begin() const { return b; }
UpDownhillPipIterator end() const { return e; }
};
struct BelPinIterator
{
const DatabasePOD *db;
const ChipInfoPOD *chip;
NeighWireIterator twi, twi_end;
int cursor = -1;
void operator++()
{
cursor++;
while (true) {
if (!(twi != twi_end))
break;
if (cursor < chip_wire_data(db, chip, *twi).bel_pins.ssize())
break;
++twi;
cursor = 0;
}
}
bool operator!=(const BelPinIterator &other) const { return twi != other.twi || cursor != other.cursor; }
BelPin operator*() const
{
BelPin ret;
WireId w = *twi;
auto &bp = chip_wire_data(db, chip, w).bel_pins[cursor];
ret.bel.tile = w.tile;
ret.bel.index = bp.bel;
ret.pin = IdString(bp.pin);
return ret;
}
};
struct BelPinRange
{
BelPinIterator b, e;
BelPinIterator begin() const { return b; }
BelPinIterator end() const { return e; }
};
// -----------------------------------------------------------------------
// This enum captures different 'styles' of cell pins
// This is a combination of the modes available for a pin (tied high, low or inverted)
// and the default value to set it to not connected
enum CellPinStyle
{
PINOPT_NONE = 0x0, // no options, just signal as-is
PINOPT_LO = 0x1, // can be tied low
PINOPT_HI = 0x2, // can be tied high
PINOPT_INV = 0x4, // can be inverted
PINOPT_LOHI = 0x3, // can be tied low or high
PINOPT_LOHIINV = 0x7, // can be tied low or high; or inverted
PINOPT_MASK = 0x7,
PINDEF_NONE = 0x00, // leave disconnected
PINDEF_0 = 0x10, // connect to 0 if not used
PINDEF_1 = 0x20, // connect to 1 if not used
PINDEF_MASK = 0x30,
PINGLB_CLK = 0x100, // pin is a 'clock' for global purposes
PINGLB_MASK = 0x100,
PINBIT_GATED = 0x1000, // pin must be enabled in bitstream if used
PINBIT_1 = 0x2000, // pin has an explicit bit that must be set if tied to 1
PINBIT_CIBMUX = 0x4000, // pin's CIBMUX must be floating for pin to be 1
PINSTYLE_NONE = 0x0000, // default
PINSTYLE_CIB = 0x4012, // 'CIB' signal, floats high but explicitly zeroed if not used
PINSTYLE_CLK = 0x0107, // CLK type signal, invertible and defaults to disconnected
PINSTYLE_CE = 0x0027, // CE type signal, invertible and defaults to enabled
PINSTYLE_LSR = 0x0017, // LSR type signal, invertible and defaults to not reset
PINSTYLE_DEDI = 0x0000, // dedicated signals, leave alone
PINSTYLE_PU = 0x4022, // signals that float high and default high
PINSTYLE_PU_NONCIB = 0x0022, // signals that float high and default high
PINSTYLE_PD_NONCIB = 0x0012, // signals that float high and default low
PINSTYLE_T = 0x4027, // PIO 'T' signal
PINSTYLE_ADLSB = 0x4017, // special case of the EBR address MSBs
PINSTYLE_INV_PD = 0x0017, // invertible, pull down by default
PINSTYLE_INV_PD_CIB = 0x4017, // invertible, pull down by default
PINSTYLE_INV_PU = 0x4027, // invertible, pull up by default
PINSTYLE_IOL_CELSR = 0x3007, // CE type signal, with explicit 'const-1' config bit
PINSTYLE_IOL_CLK = 0x3107, // CE type signal, with explicit 'const-1' config bit
PINSTYLE_GATE = 0x1011, // gated signal that defaults to 0
};
// This represents the mux options for a pin
enum CellPinMux
{
PINMUX_SIG = 0,
PINMUX_0 = 1,
PINMUX_1 = 2,
PINMUX_INV = 3,
};
// This represents the various kinds of IO pins
enum IOStyle
{
IOBANK_WR = 0x1, // needs wide range IO bank
IOBANK_HP = 0x2, // needs high perf IO bank
IOMODE_REF = 0x10, // IO is referenced
IOMODE_DIFF = 0x20, // IO is true differential
IOMODE_PSEUDO_DIFF = 0x40, // IO is pseduo differential
IOSTYLE_SE_WR = 0x01, // single ended, wide range
IOSTYLE_SE_HP = 0x02, // single ended, high perf
IOSTYLE_PD_WR = 0x41, // pseudo diff, wide range
IOSTYLE_REF_HP = 0x12, // referenced high perf
IOSTYLE_DIFF_HP = 0x22, // differential high perf
};
struct IOTypeData
{
IOStyle style;
int vcco; // required Vcco in 10mV
};
// -----------------------------------------------------------------------
const int bba_version =
#include "bba_version.inc"
;
struct ArchArgs
{
std::string device;
};
struct ArchRanges : BaseArchRanges
{
using ArchArgsT = ArchArgs;
// Bels
using AllBelsRangeT = BelRange;
using TileBelsRangeT = std::vector<BelId>;
using BelPinsRangeT = std::vector<IdString>;
// Wires
using AllWiresRangeT = WireRange;
using DownhillPipRangeT = UpDownhillPipRange;
using UphillPipRangeT = UpDownhillPipRange;
using WireBelPinRangeT = BelPinRange;
// Pips
using AllPipsRangeT = AllPipRange;
};
struct Arch : BaseArch<ArchRanges>
{
ArchArgs args;
std::string family, device, package, speed, rating, variant;
Arch(ArchArgs args);
// -------------------------------------------------
// Database references
boost::iostreams::mapped_file_source blob_file;
const DatabasePOD *db;
const ChipInfoPOD *chip_info;
const SpeedGradePOD *speed_grade;
int package_idx;
// Binding states
struct LogicTileStatus
{
struct SliceStatus
{
bool valid = true, dirty = true;
} slices[4];
struct HalfTileStatus
{
bool valid = true, dirty = true;
} halfs[2];
CellInfo *cells[32];
};
struct TileStatus
{
std::vector<CellInfo *> boundcells;
std::vector<BelId> bels_by_z;
std::vector<NetInfo *> boundwires, boundpips;
LogicTileStatus *lts = nullptr;
~TileStatus() { delete lts; }
};
std::vector<TileStatus> tileStatus;
// fast access to X and Y IdStrings for building object names
std::vector<IdString> x_ids, y_ids;
// inverse of the above for name->object mapping
dict<IdString, int> id_to_x, id_to_y;
pool<PipId> disabled_pips;
// -------------------------------------------------
std::string getChipName() const override;
ArchArgs archArgs() const override { return args; }
IdString archArgsToId(ArchArgs args) const override;
int getGridDimX() const override { return chip_info->width; }
int getGridDimY() const override { return chip_info->height; }
int getTileBelDimZ(int, int) const override { return 256; }
int getTilePipDimZ(int, int) const override { return 1; }
char getNameDelimiter() const override { return '/'; }
// -------------------------------------------------
BelId getBelByName(IdStringList name) const override;
IdStringList getBelName(BelId bel) const override
{
NPNR_ASSERT(bel != BelId());
std::array<IdString, 3> ids{x_ids.at(bel.tile % chip_info->width), y_ids.at(bel.tile / chip_info->width),
IdString(bel_data(bel).name)};
return IdStringList(ids);
}
void bindBel(BelId bel, CellInfo *cell, PlaceStrength strength) override
{
NPNR_ASSERT(bel != BelId());
NPNR_ASSERT(tileStatus[bel.tile].boundcells[bel.index] == nullptr);
tileStatus[bel.tile].boundcells[bel.index] = cell;
cell->bel = bel;
cell->belStrength = strength;
refreshUiBel(bel);
if (bel_tile_is(bel, LOC_LOGIC))
update_logic_bel(bel, cell);
}
void unbindBel(BelId bel) override
{
NPNR_ASSERT(bel != BelId());
NPNR_ASSERT(tileStatus[bel.tile].boundcells[bel.index] != nullptr);
if (bel_tile_is(bel, LOC_LOGIC))
update_logic_bel(bel, nullptr);
tileStatus[bel.tile].boundcells[bel.index]->bel = BelId();
tileStatus[bel.tile].boundcells[bel.index]->belStrength = STRENGTH_NONE;
tileStatus[bel.tile].boundcells[bel.index] = nullptr;
refreshUiBel(bel);
}
bool checkBelAvail(BelId bel) const override
{
NPNR_ASSERT(bel != BelId());
return tileStatus[bel.tile].boundcells[bel.index] == nullptr;
}
bool is_pseudo_pip_disabled(PipId pip) const
{
const auto &data = pip_data(pip);
if (data.flags & PIP_LUT_PERM) {
int lut_idx = (data.flags >> 8) & 0xF;
int from_pin = (data.flags >> 4) & 0xF;
int to_pin = (data.flags >> 0) & 0xF;
auto &ts = tileStatus.at(pip.tile);
if (!ts.lts)
return false;
const CellInfo *lut = ts.lts->cells[((lut_idx / 2) << 3) | (BEL_LUT0 + (lut_idx % 2))];
if (lut) {
if (lut->lutInfo.is_memory)
return true;
if (lut->lutInfo.is_carry && (from_pin == 3 || to_pin == 3))
return true; // Upper pin is special for carries
}
if (lut_idx == 4 || lut_idx == 5) {
const CellInfo *ramw = ts.lts->cells[((lut_idx / 2) << 3) | BEL_RAMW];
if (ramw)
return true; // Don't permute RAM write address
}
}
return false;
}
bool checkPipAvail(PipId pip) const override
{
if (disabled_pips.count(pip))
return false;
if (is_pseudo_pip_disabled(pip))
return false;
return getBoundPipNet(pip) == nullptr;
}
bool checkPipAvailForNet(PipId pip, const NetInfo *net) const override
{
if (disabled_pips.count(pip))
return false;
if (is_pseudo_pip_disabled(pip))
return false;
NetInfo *bound = getBoundPipNet(pip);
return (bound == nullptr) || (bound == net);
}
CellInfo *getBoundBelCell(BelId bel) const override
{
NPNR_ASSERT(bel != BelId());
return tileStatus[bel.tile].boundcells[bel.index];
}
BelRange getBels() const override
{
BelRange range;
range.b.cursor_tile = 0;
range.b.cursor_index = -1;
range.b.chip = chip_info;
range.b.db = db;
++range.b; //-1 and then ++ deals with the case of no bels in the first tile
range.e.cursor_tile = chip_info->width * chip_info->height;
range.e.cursor_index = 0;
range.e.chip = chip_info;
range.e.db = db;
return range;
}
Loc getBelLocation(BelId bel) const override
{
NPNR_ASSERT(bel != BelId());
Loc loc;
loc.x = bel.tile % chip_info->width + bel_data(bel).rel_x;
loc.y = bel.tile / chip_info->width + bel_data(bel).rel_y;
loc.z = bel_data(bel).z;
return loc;
}
BelId getBelByLocation(Loc loc) const override
{
auto &t = tileStatus.at(loc.y * chip_info->width + loc.x);
if (loc.z >= int(t.bels_by_z.size()))
return BelId();
return t.bels_by_z.at(loc.z);
}
std::vector<BelId> getBelsByTile(int x, int y) const override;
bool getBelGlobalBuf(BelId bel) const override
{
IdString type = getBelType(bel);
return type.in(id_DCC, id_VCC_DRV);
}
IdString getBelType(BelId bel) const override
{
NPNR_ASSERT(bel != BelId());
return IdString(bel_data(bel).type);
}
std::vector<std::pair<IdString, std::string>> getBelAttrs(BelId bel) const override;
WireId getBelPinWire(BelId bel, IdString pin) const override;
PortType getBelPinType(BelId bel, IdString pin) const override;
std::vector<IdString> getBelPins(BelId bel) const override;
// -------------------------------------------------
WireId getWireByName(IdStringList name) const override;
IdStringList getWireName(WireId wire) const override
{
NPNR_ASSERT(wire != WireId());
std::array<IdString, 3> ids{x_ids.at(wire.tile % chip_info->width), y_ids.at(wire.tile / chip_info->width),
IdString(wire_data(wire).name)};
return IdStringList(ids);
}
std::vector<std::pair<IdString, std::string>> getWireAttrs(WireId wire) const override;
IdString getWireType(WireId wire) const override;
DelayQuad getWireDelay(WireId wire) const override { return DelayQuad(0); }
BelPinRange getWireBelPins(WireId wire) const override
{
BelPinRange range;
NPNR_ASSERT(wire != WireId());
NeighWireRange nwr = neigh_wire_range(wire);
range.b.chip = chip_info;
range.b.db = db;
range.b.twi = nwr.b;
range.b.twi_end = nwr.e;
range.b.cursor = -1;
++range.b;
range.e.chip = chip_info;
range.e.db = db;
range.e.twi = nwr.e;
range.e.twi_end = nwr.e;
range.e.cursor = 0;
return range;
}
WireRange getWires() const override
{
WireRange range;
range.b.chip = chip_info;
range.b.db = db;
range.b.cursor_tile = 0;
range.b.cursor_index = -1;
++range.b; //-1 and then ++ deals with the case of no wires in the first tile
range.e.chip = chip_info;
range.e.db = db;
range.e.cursor_tile = chip_info->grid.size();
range.e.cursor_index = 0;
return range;
}
void bindWire(WireId wire, NetInfo *net, PlaceStrength strength) override
{
NPNR_ASSERT(wire != WireId());
auto &w2n_entry = tileStatus.at(wire.tile).boundwires.at(wire.index);
NPNR_ASSERT(w2n_entry == nullptr);
net->wires[wire].pip = PipId();
net->wires[wire].strength = strength;
w2n_entry = net;
this->refreshUiWire(wire);
}
void unbindWire(WireId wire) override
{
NPNR_ASSERT(wire != WireId());
auto &w2n_entry = tileStatus.at(wire.tile).boundwires.at(wire.index);
NPNR_ASSERT(w2n_entry != nullptr);
auto &net_wires = w2n_entry->wires;
auto it = net_wires.find(wire);
NPNR_ASSERT(it != net_wires.end());
auto pip = it->second.pip;
if (pip != PipId()) {
tileStatus.at(pip.tile).boundpips.at(pip.index) = nullptr;
}
net_wires.erase(it);
w2n_entry = nullptr;
this->refreshUiWire(wire);
}
virtual bool checkWireAvail(WireId wire) const override { return getBoundWireNet(wire) == nullptr; }
NetInfo *getBoundWireNet(WireId wire) const override { return tileStatus.at(wire.tile).boundwires.at(wire.index); }
IdString getWireConstantValue(WireId wire) const override
{
if (chip_wire_data(db, chip_info, wire).name == ID_LOCAL_VCC)
return id_VCC_DRV;
else
return {};
}
// -------------------------------------------------
PipId getPipByName(IdStringList name) const override;
IdStringList getPipName(PipId pip) const override;
AllPipRange getPips() const override
{
AllPipRange range;
range.b.cursor_tile = 0;
range.b.cursor_index = -1;
range.b.chip = chip_info;
range.b.db = db;
++range.b; //-1 and then ++ deals with the case of no pips in the first tile
range.e.cursor_tile = chip_info->width * chip_info->height;
range.e.cursor_index = 0;
range.e.chip = chip_info;
range.e.db = db;
return range;
}
Loc getPipLocation(PipId pip) const override
{
Loc loc;
loc.x = pip.tile % chip_info->width;
loc.y = pip.tile / chip_info->width;
loc.z = 0;
return loc;
}
IdString getPipType(PipId pip) const override;
std::vector<std::pair<IdString, std::string>> getPipAttrs(PipId pip) const override;
WireId getPipSrcWire(PipId pip) const override { return canonical_wire(pip.tile, pip_data(pip).from_wire); }
WireId getPipDstWire(PipId pip) const override { return canonical_wire(pip.tile, pip_data(pip).to_wire); }
DelayQuad getPipDelay(PipId pip) const override
{
auto &cls = speed_grade->pip_classes[pip_data(pip).timing_class];
return DelayQuad(std::max(0, cls.min_delay), std::max(0, cls.max_delay));
}
UpDownhillPipRange getPipsDownhill(WireId wire) const override
{
UpDownhillPipRange range;
NPNR_ASSERT(wire != WireId());
NeighWireRange nwr = neigh_wire_range(wire);
range.b.chip = chip_info;
range.b.db = db;
range.b.twi = nwr.b;
range.b.twi_end = nwr.e;
range.b.cursor = -1;
range.b.uphill = false;
++range.b;
range.e.chip = chip_info;
range.e.db = db;
range.e.twi = nwr.e;
range.e.twi_end = nwr.e;
range.e.cursor = 0;
range.e.uphill = false;
return range;
}
UpDownhillPipRange getPipsUphill(WireId wire) const override
{
UpDownhillPipRange range;
NPNR_ASSERT(wire != WireId());
NeighWireRange nwr = neigh_wire_range(wire);
range.b.chip = chip_info;
range.b.db = db;
range.b.twi = nwr.b;
range.b.twi_end = nwr.e;
range.b.cursor = -1;
range.b.uphill = true;
++range.b;
range.e.chip = chip_info;
range.e.db = db;
range.e.twi = nwr.e;
range.e.twi_end = nwr.e;
range.e.cursor = 0;
range.e.uphill = true;
return range;
}
void bindPip(PipId pip, NetInfo *net, PlaceStrength strength) override
{
NPNR_ASSERT(pip != PipId());
auto &p2n_entry = tileStatus.at(pip.tile).boundpips.at(pip.index);
NPNR_ASSERT(p2n_entry == nullptr);
p2n_entry = net;
WireId dst = this->getPipDstWire(pip);
auto &w2n_entry = tileStatus.at(dst.tile).boundwires.at(dst.index);
NPNR_ASSERT(w2n_entry == nullptr);
w2n_entry = net;
net->wires[dst].pip = pip;
net->wires[dst].strength = strength;
}
void unbindPip(PipId pip) override
{
NPNR_ASSERT(pip != PipId());
auto &p2n_entry = tileStatus.at(pip.tile).boundpips.at(pip.index);
NPNR_ASSERT(p2n_entry != nullptr);
WireId dst = this->getPipDstWire(pip);
auto &w2n_entry = tileStatus.at(dst.tile).boundwires.at(dst.index);
NPNR_ASSERT(w2n_entry != nullptr);
w2n_entry = nullptr;
p2n_entry->wires.erase(dst);
p2n_entry = nullptr;
}
NetInfo *getBoundPipNet(PipId pip) const override { return tileStatus.at(pip.tile).boundpips.at(pip.index); }
// -------------------------------------------------
int32_t estimate_delay_mult;
delay_t estimateDelay(WireId src, WireId dst) const override;
delay_t predictDelay(BelId src_bel, IdString src_pin, BelId dst_bel, IdString dst_pin) const override;
delay_t getDelayEpsilon() const override { return 20; }
delay_t getRipupDelayPenalty() const override;
delay_t getWireRipupDelayPenalty(WireId wire) const;
float getDelayNS(delay_t v) const override { return v * 0.001; }
delay_t getDelayFromNS(float ns) const override { return delay_t(ns * 1000); }
uint32_t getDelayChecksum(delay_t v) const override { return v; }
BoundingBox getRouteBoundingBox(WireId src, WireId dst) const override;
// for better DSP bounding boxes
void pre_routing();
pool<WireId> dsp_wires, lram_wires;
// -------------------------------------------------
// Get the delay through a cell from one port to another, returning false
// if no path exists. This only considers combinational delays, as required by the Arch API
bool getCellDelay(const CellInfo *cell, IdString fromPort, IdString toPort, DelayQuad &delay) const override;
// Get the port class, also setting clockInfoCount to the number of TimingClockingInfos associated with a port
TimingPortClass getPortTimingClass(const CellInfo *cell, IdString port, int &clockInfoCount) const override;
// Get the TimingClockingInfo of a port
TimingClockingInfo getPortClockingInfo(const CellInfo *cell, IdString port, int index) const override;
// -------------------------------------------------
// Perform placement validity checks, returning false on failure (all
// implemented in arch_place.cc)
// Return true whether all Bels at a given location are valid
bool isBelLocationValid(BelId bel, bool explain_invalid = false) const override;
// -------------------------------------------------
bool pack() override;
bool place() override;
bool route() override;
// arch-specific post-placement optimisations
void post_place_opt();
// -------------------------------------------------
// Assign architecture-specific arguments to nets and cells, which must be
// called between packing or further
// netlist modifications, and validity checks
void assignArchInfo() override;
void assignCellInfo(CellInfo *cell);
// -------------------------------------------------
// Arch-specific global routing
void route_globals();
// -------------------------------------------------
// Override for DSP clusters
bool getClusterPlacement(ClusterId cluster, BelId root_bel,
std::vector<std::pair<CellInfo *, BelId>> &placement) const override;
// -------------------------------------------------
std::vector<GraphicElement> getDecalGraphics(DecalId decal) const override;
DecalXY getBelDecal(BelId bel) const override;
DecalXY getWireDecal(WireId wire) const override;
DecalXY getPipDecal(PipId pip) const override;
DecalXY getGroupDecal(GroupId group) const override;
// -------------------------------------------------
static const std::string defaultPlacer;
static const std::vector<std::string> availablePlacers;
static const std::string defaultRouter;
static const std::vector<std::string> availableRouters;
// -------------------------------------------------
template <typename Id> const LocTypePOD &loc_data(const Id &id) const { return chip_loc_data(db, chip_info, id); }
template <typename Id> const LocNeighourhoodPOD &nh_data(const Id &id) const
{
return chip_nh_data(db, chip_info, id);
}
inline const BelInfoPOD &bel_data(BelId id) const { return chip_bel_data(db, chip_info, id); }
inline const LocWireInfoPOD &wire_data(WireId id) const { return chip_wire_data(db, chip_info, id); }
inline const PipInfoPOD &pip_data(PipId id) const { return chip_pip_data(db, chip_info, id); }
inline bool rel_tile(int32_t base, int16_t rel_x, int16_t rel_y, int32_t &next) const
{
return chip_rel_tile(chip_info, base, rel_x, rel_y, next);
}
inline WireId canonical_wire(int32_t tile, uint16_t index) const
{
WireId c = chip_canonical_wire(db, chip_info, tile, index);
return c;
}
IdString pip_src_wire_name(PipId pip) const
{
int wire = pip_data(pip).from_wire;
return IdString(db->loctypes[chip_info->grid[pip.tile].loc_type].wires[wire].name);
}
IdString pip_dst_wire_name(PipId pip) const
{
int wire = pip_data(pip).to_wire;
return IdString(db->loctypes[chip_info->grid[pip.tile].loc_type].wires[wire].name);
}
// -------------------------------------------------
typedef dict<IdString, CellPinStyle> CellPinsData;
dict<IdString, CellPinsData> cell_pins_db;
CellPinStyle get_cell_pin_style(const CellInfo *cell, IdString port) const;
void init_cell_pin_data();
// -------------------------------------------------
// Parse a possibly-Lattice-style (C literal in Verilog string) style parameter
Property parse_lattice_param_from_cell(const CellInfo *ci, IdString prop, int width, int64_t defval) const;
Property parse_lattice_param(const Property &val, IdString prop, int width, const char *ci = "") const;
// -------------------------------------------------
NeighWireRange neigh_wire_range(WireId wire) const
{
NeighWireRange range;
range.b.chip = chip_info;
range.b.db = db;
range.b.baseWire = wire;
range.b.cursor = -1;
range.e.chip = chip_info;
range.e.db = db;
range.e.baseWire = wire;
range.e.cursor = nh_data(wire).wire_neighbours[wire.index].neigh_wires.size();
return range;
}
// -------------------------------------------------
template <typename TId> uint32_t tile_loc_flags(TId id) const { return chip_info->grid[id.tile].loc_flags; }
template <typename TId> bool tile_is(TId id, LocFlags lf) const { return tile_loc_flags(id) & lf; }
bool bel_tile_is(BelId bel, LocFlags lf) const
{
int32_t tile;
NPNR_ASSERT(rel_tile(bel.tile, bel_data(bel).rel_x, bel_data(bel).rel_y, tile));
return chip_info->grid[tile].loc_flags & lf;
}
// -------------------------------------------------
enum LogicBelZ
{
BEL_LUT0 = 0,
BEL_LUT1 = 1,
BEL_FF0 = 2,
BEL_FF1 = 3,
BEL_RAMW = 4,
};
void update_logic_bel(BelId bel, CellInfo *cell)
{
int z = bel_data(bel).z;
NPNR_ASSERT(z < 32);
auto &tts = tileStatus[bel.tile];
if (tts.lts == nullptr)
tts.lts = new LogicTileStatus();
auto &ts = *(tts.lts);
ts.cells[z] = cell;
switch (z & 0x7) {
case BEL_FF0:
case BEL_FF1:
case BEL_RAMW:
ts.halfs[(z >> 3) / 2].dirty = true;
/* fall-through */
case BEL_LUT0:
case BEL_LUT1:
ts.slices[(z >> 3)].dirty = true;
break;
}
}
bool nexus_logic_tile_valid(LogicTileStatus &lts) const;
CellPinMux get_cell_pinmux(const CellInfo *cell, IdString pin) const;
void set_cell_pinmux(CellInfo *cell, IdString pin, CellPinMux state);
// -------------------------------------------------
const PadInfoPOD *get_pkg_pin_data(const std::string &pin) const;
Loc get_pad_loc(const PadInfoPOD *pad) const;
BelId get_pad_pio_bel(const PadInfoPOD *pad) const;
const PadInfoPOD *get_bel_pad(BelId bel) const;
std::string get_pad_functions(const PadInfoPOD *pad) const;
// -------------------------------------------------
// Data about different IO standard, mostly used by bitgen
static const dict<std::string, IOTypeData> io_types;
int get_io_type_vcc(const std::string &io_type) const;
bool is_io_type_diff(const std::string &io_type) const;
bool is_io_type_ref(const std::string &io_type) const;
// -------------------------------------------------
// Cell timing lookup helpers
bool is_dsp_cell(const CellInfo *cell) const;
// Given cell type and variant, get the index inside the speed grade timing data
int get_cell_timing_idx(IdString cell_type, IdString cell_variant = IdString()) const;
// Return true and set delay if a comb path exists in a given cell timing index
bool lookup_cell_delay(int type_idx, IdString from_port, IdString to_port, DelayQuad &delay) const;
// Get setup and hold time for a given cell timing index and signal/clock pair
void lookup_cell_setuphold(int type_idx, IdString from_port, IdString clock, DelayPair &setup,
DelayPair &hold) const;
// Get setup and hold time and associated clock for a given cell timing index and signal
void lookup_cell_setuphold_clock(int type_idx, IdString from_port, IdString &clock, DelayPair &setup,
DelayPair &hold) const;
// Similar to lookup_cell_delay but only needs the 'to' signal, intended for clk->out delays
void lookup_cell_clock_out(int type_idx, IdString to_port, IdString &clock, DelayQuad &delay) const;
// Attempt to look up port type based on database
TimingPortClass lookup_port_type(int type_idx, IdString port, PortType dir, IdString clock) const;
// -------------------------------------------------
// List of IO constraints, used by PDC parser
dict<IdString, dict<IdString, Property>> io_attr;
void read_pdc(std::istream &in);
// -------------------------------------------------
void write_fasm(std::ostream &out) const;
// -------------------------------------------------
static void list_devices();
};
NEXTPNR_NAMESPACE_END
#endif /* NEXUS_ARCH_H */