From 946083410f403c1434fc256718cd983649071658 Mon Sep 17 00:00:00 2001
From: Gabriel Somlo <gsomlo@gmail.com>
Date: Sun, 24 Sep 2023 23:14:50 -0400
Subject: [PATCH] core: add edge-triggered irq signal for command completion

---
 litesdcard/core.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/litesdcard/core.py b/litesdcard/core.py
index 43a9d65..95b99aa 100644
--- a/litesdcard/core.py
+++ b/litesdcard/core.py
@@ -24,6 +24,7 @@ class SDCore(LiteXModule):
     def __init__(self, phy):
         self.sink   = stream.Endpoint([("data", 8)])
         self.source = stream.Endpoint([("data", 8)])
+        self.irq = Signal()
 
         # Cmd Registers.
         self.cmd_argument = CSRStorage(32, description="SDCard Cmd Argument.")
@@ -115,6 +116,11 @@ def __init__(self, phy):
             crc7_inserter.enable.eq(1),
         ]
 
+        # IRQ / Generate IRQ on CMD done rising edge
+        done_d     = Signal()
+        self.sync += done_d.eq(cmd_done)
+        self.sync += self.irq.eq(cmd_done & ~done_d)
+
         # Main FSM ---------------------------------------------------------------------------------
         self.fsm = fsm = FSM()
         fsm.act("IDLE",