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-rw-r--r--ice40/bitstream.cc94
1 files changed, 50 insertions, 44 deletions
diff --git a/ice40/bitstream.cc b/ice40/bitstream.cc
index c32680ee..d2c2ac16 100644
--- a/ice40/bitstream.cc
+++ b/ice40/bitstream.cc
@@ -356,8 +356,45 @@ void write_asc(const Context *ctx, std::ostream &out)
}
}
- std::unordered_set<Loc> sb_io_used_by_pll;
- std::unordered_set<Loc> sb_io_used_by_io;
+ // Scan for PLL and collects the affected SB_IOs
+ std::unordered_set<Loc> sb_io_used_by_pll_out;
+ std::unordered_set<Loc> sb_io_used_by_pll_pad;
+
+ for (auto &cell : ctx->cells) {
+ if (cell.second->type != ctx->id("ICESTORM_PLL"))
+ continue;
+
+ // Collect all locations matching an PLL output port
+ // note: It doesn't matter if the port is connected or not, or if fabric/global
+ // is used. As long as it's a PLL type for which the port exists, the SB_IO
+ // is not available and must be configured for PLL mode
+ const std::vector<IdString> ports = {id_PLLOUT_A, id_PLLOUT_B};
+ for (auto &port : ports) {
+ // If the output is not enabled in this mode, ignore it
+ if (port == id_PLLOUT_B && !is_sb_pll40_dual(ctx, cell.second.get()))
+ continue;
+
+ // Get IO Bel that this PLL port goes through by finding sibling
+ // Bel driving the same wire via PIN_D_IN_0.
+ auto wire = ctx->getBelPinWire(cell.second->bel, port);
+ BelId io_bel;
+ for (auto pin : ctx->getWireBelPins(wire)) {
+ if (pin.pin == id_D_IN_0) {
+ io_bel = pin.bel;
+ break;
+ }
+ }
+ NPNR_ASSERT(io_bel.index != -1);
+ auto io_bel_loc = ctx->getBelLocation(io_bel);
+
+ // Mark this SB_IO as being used by a PLL output path
+ sb_io_used_by_pll_out.insert(io_bel_loc);
+
+ // If this is a PAD PLL, and this is the 'PLLOUT_A' port, then the same SB_IO is also PAD
+ if (port == id_PLLOUT_A && is_sb_pll40_pad(ctx, cell.second.get()))
+ sb_io_used_by_pll_pad.insert(io_bel_loc);
+ }
+ }
// Set logic cell config
for (auto &cell : ctx->cells) {
@@ -445,14 +482,15 @@ void write_asc(const Context *ctx, std::ostream &out)
} else if (cell.second->type == ctx->id("SB_IO")) {
const BelInfoPOD &beli = ci.bel_data[bel.index];
int x = beli.x, y = beli.y, z = beli.z;
- sb_io_used_by_io.insert(Loc(x, y, z));
const TileInfoPOD &ti = bi.tiles_nonrouting[TILE_IO];
unsigned pin_type = get_param_or_def(cell.second.get(), ctx->id("PIN_TYPE"));
bool neg_trigger = get_param_or_def(cell.second.get(), ctx->id("NEG_TRIGGER"));
bool pullup = get_param_or_def(cell.second.get(), ctx->id("PULLUP"));
bool lvds = get_param_str_or_def(cell.second.get(), ctx->id("IO_STANDARD")) == "SB_LVDS_INPUT";
+ bool used_by_pll_out = sb_io_used_by_pll_out.count(Loc(x, y, z)) > 0;
+ bool used_by_pll_pad = sb_io_used_by_pll_pad.count(Loc(x, y, z)) > 0;
- for (int i = 0; i < 6; i++) {
+ for (int i = used_by_pll_out ? 2 : 0; i < 6; i++) {
bool val = (pin_type >> i) & 0x01;
set_config(ti, config.at(y).at(x), "IOB_" + std::to_string(z) + ".PINTYPE_" + std::to_string(i), val);
}
@@ -475,6 +513,8 @@ void write_asc(const Context *ctx, std::ostream &out)
}
}
+ input_en = (input_en & !used_by_pll_out) | used_by_pll_pad;
+
if (ctx->args.type == ArchArgs::LP1K || ctx->args.type == ArchArgs::HX1K) {
set_config(ti, config.at(iey).at(iex), "IoCtrl.IE_" + std::to_string(iez), !input_en);
set_config(ti, config.at(iey).at(iex), "IoCtrl.REN_" + std::to_string(iez), !pullup);
@@ -613,47 +653,13 @@ void write_asc(const Context *ctx, std::ostream &out)
configure_extra_cell(config, ctx, cell.second.get(), pll_params, false, std::string("PLL."));
// Configure the SB_IOs that the clock outputs are going through.
- for (auto &port : cell.second->ports) {
- // If this port is not a PLLOUT port, ignore it.
- if (port.second.name != ctx->id("PLLOUT_A") && port.second.name != ctx->id("PLLOUT_B"))
- continue;
-
- // If the output is not driving any net, ignore it.
- if (port.second.net == nullptr)
- continue;
-
- // Get IO Bel that this PLL port goes through by finding sibling
- // Bel driving the same wire via PIN_D_IN_0.
- auto wire = ctx->getBelPinWire(cell.second->bel, port.second.name);
- BelId io_bel;
- for (auto pin : ctx->getWireBelPins(wire)) {
- if (pin.pin == id_D_IN_0) {
- io_bel = pin.bel;
- break;
- }
- }
- NPNR_ASSERT(io_bel.index != -1);
- auto io_bel_loc = ctx->getBelLocation(io_bel);
-
- // Check that this SB_IO is either unused or just used as an output.
- if (sb_io_used_by_io.count(io_bel_loc)) {
- log_error("SB_IO '%s' already in use, cannot route PLL through\n", ctx->getBelName(bel).c_str(ctx));
- }
- sb_io_used_by_pll.insert(io_bel_loc);
-
- // Get IE/REN config location (cf. http://www.clifford.at/icestorm/io_tile.html)
- auto ieren = get_ieren(bi, io_bel_loc.x, io_bel_loc.y, io_bel_loc.z);
- int iex, iey, iez;
- std::tie(iex, iey, iez) = ieren;
- NPNR_ASSERT(iez != -1);
-
+ for (auto &io_bel_loc : sb_io_used_by_pll_out) {
// Write config.
const TileInfoPOD &ti = bi.tiles_nonrouting[TILE_IO];
- // Enable input buffer and disable pull-up resistor in block
- // (this is used by the PLL).
- set_ie_bit_logical(ctx, ti, config.at(iey).at(iex), "IoCtrl.IE_" + std::to_string(iez), true);
- set_ie_bit_logical(ctx, ti, config.at(iey).at(iex), "IoCtrl.REN_" + std::to_string(iez), false);
- // PINTYPE[0] passes the PLL through to the fabric.
+
+ // PINTYPE[1:0] == "01" passes the PLL through to the fabric.
+ set_config(ti, config.at(io_bel_loc.y).at(io_bel_loc.x),
+ "IOB_" + std::to_string(io_bel_loc.z) + ".PINTYPE_1", false);
set_config(ti, config.at(io_bel_loc.y).at(io_bel_loc.x),
"IOB_" + std::to_string(io_bel_loc.z) + ".PINTYPE_0", true);
}
@@ -668,7 +674,7 @@ void write_asc(const Context *ctx, std::ostream &out)
const TileInfoPOD &ti = bi.tiles_nonrouting[TILE_IO];
const BelInfoPOD &beli = ci.bel_data[bel.index];
int x = beli.x, y = beli.y, z = beli.z;
- if (sb_io_used_by_pll.count(Loc(x, y, z))) {
+ if (sb_io_used_by_pll_out.count(Loc(x, y, z))) {
continue;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-29 14:30:58 +0000