From: Florent Kermarrec <florent@enjoy-digital.fr>
Date: Tue, 31 Mar 2020 14:54:38 +0000 (+0200)
Subject: soc/cores/uart: use reset_less on accumulator, reg, bitcount to reduce.
X-Git-Tag: 24jan2021_ls180~507
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=91981b960c949aa117507488da2bccb2728040ad;p=litex.git

soc/cores/uart: use reset_less on accumulator, reg, bitcount to reduce.

This reduces logic a bit. It does not make large difference on usual design with
only 1 UART, but is interesting on designs with hundreds of UARTs used to "document"
FPGA boards :) (similar to https://github.com/enjoy-digital/camlink_4k/blob/master/ios_stream.py)
---

diff --git a/litex/soc/cores/uart.py b/litex/soc/cores/uart.py
index 4eda4c27..e6315016 100644
--- a/litex/soc/cores/uart.py
+++ b/litex/soc/cores/uart.py
@@ -35,12 +35,12 @@ class RS232PHYRX(Module):
         # # #
 
         uart_clk_rxen        = Signal()
-        phase_accumulator_rx = Signal(32)
+        phase_accumulator_rx = Signal(32, reset_less=True)
 
         rx          = Signal()
         rx_r        = Signal()
-        rx_reg      = Signal(8)
-        rx_bitcount = Signal(4)
+        rx_reg      = Signal(8, reset_less=True)
+        rx_bitcount = Signal(4, reset_less=True)
         rx_busy     = Signal()
         rx_done     = self.source.valid
         rx_data     = self.source.data
@@ -87,12 +87,12 @@ class RS232PHYTX(Module):
         # # #
 
         uart_clk_txen        = Signal()
-        phase_accumulator_tx = Signal(32)
+        phase_accumulator_tx = Signal(32, reset_less=True)
 
         pads.tx.reset = 1
 
-        tx_reg      = Signal(8)
-        tx_bitcount = Signal(4)
+        tx_reg      = Signal(8, reset_less=True)
+        tx_bitcount = Signal(4, reset_less=True)
         tx_busy     = Signal()
         self.sync += [
             self.sink.ready.eq(0),