From 7fae169bbb3f0ffb1b7dd8afff89ea183104194c Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <stenzek@gmail.com>
Date: Sat, 25 Apr 2020 14:17:44 +1000
Subject: [PATCH] Timer: Don't let writes affect IRQ state
---
src/core/timers.cpp | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/src/core/timers.cpp b/src/core/timers.cpp
index 124895220..9022d6ed2 100644
--- a/src/core/timers.cpp
+++ b/src/core/timers.cpp
@@ -25,6 +25,7 @@ void Timers::Reset()
for (CounterState& cs : m_states)
{
cs.mode.bits = 0;
+ cs.mode.interrupt_request_n = true;
cs.counter = 0;
cs.target = 0;
cs.gate = false;
@@ -231,13 +232,13 @@ void Timers::WriteRegister(u32 offset, u32 value)
case 0x04:
{
+ static constexpr u32 WRITE_MASK = 0b1110001111111111;
+
Log_DebugPrintf("Timer %u write mode register 0x%04X", timer_index, value);
- cs.mode.bits = value & u32(0x1FFF);
+ cs.mode.bits = (value & WRITE_MASK) | (cs.mode.bits & ~WRITE_MASK);
cs.use_external_clock = (cs.mode.clock_source & (timer_index == 2 ? 2 : 1)) != 0;
cs.counter = 0;
cs.irq_done = false;
- if (cs.mode.irq_pulse_n)
- cs.mode.interrupt_request_n = true;
UpdateCountingEnabled(cs);
UpdateIRQ(timer_index);