From 308471da8c592b6c95c863e3bf79e8955c024044 Mon Sep 17 00:00:00 2001
From: ergo720 <45463469+ergo720@users.noreply.github.com>
Date: Mon, 5 Aug 2024 01:54:46 +0200
Subject: [PATCH] Make some gpu registers atomic to ensure thread-safety in
 pfifo::worker

---
 src/hw/video/gpu/pcrtc.hpp  | 5 +++--
 src/hw/video/gpu/pfb.hpp    | 3 ++-
 src/hw/video/gpu/pmc.hpp    | 5 +++--
 src/hw/video/gpu/ptimer.hpp | 5 +++--
 4 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/hw/video/gpu/pcrtc.hpp b/src/hw/video/gpu/pcrtc.hpp
index 68eae8f..28e5d08 100644
--- a/src/hw/video/gpu/pcrtc.hpp
+++ b/src/hw/video/gpu/pcrtc.hpp
@@ -5,6 +5,7 @@
 #pragma once
 
 #include <cstdint>
+#include <atomic>
 #include "nv2a_defs.hpp"
 
 #define NV_PCRTC 0x00600000
@@ -41,8 +42,8 @@ class pcrtc {
 	friend class pmc;
 	machine *const m_machine;
 	struct {
-		uint32_t int_status;
-		uint32_t int_enabled;
+		std::atomic_uint32_t int_status; // accessed from pfifo::worker with pmc::update_irq()
+		std::atomic_uint32_t int_enabled; // accessed from pfifo::worker with pmc::update_irq()
 		uint32_t fb_addr;
 		uint32_t unknown[1];
 	};
diff --git a/src/hw/video/gpu/pfb.hpp b/src/hw/video/gpu/pfb.hpp
index a9df288..1ce0fb4 100644
--- a/src/hw/video/gpu/pfb.hpp
+++ b/src/hw/video/gpu/pfb.hpp
@@ -5,6 +5,7 @@
 #pragma once
 
 #include <cstdint>
+#include <atomic>
 #include "nv2a_defs.hpp"
 
 #define NV_PFB 0x00100000
@@ -41,6 +42,6 @@ class pfb {
 	struct {
 		uint32_t cfg0, cfg1;
 		uint32_t nvm;
-		uint32_t cstatus;
+		std::atomic_uint32_t cstatus; // accessed from pfifo::worker with nv2a::get_dma_obj()
 	};
 };
diff --git a/src/hw/video/gpu/pmc.hpp b/src/hw/video/gpu/pmc.hpp
index 57e331a..476f82b 100644
--- a/src/hw/video/gpu/pmc.hpp
+++ b/src/hw/video/gpu/pmc.hpp
@@ -5,6 +5,7 @@
 #pragma once
 
 #include <cstdint>
+#include <atomic>
 #include "nv2a_defs.hpp"
 
 #define NV_PMC 0x00000000
@@ -83,8 +84,8 @@ class pmc {
 	machine *const m_machine;
 	struct {
 		uint32_t endianness;
-		uint32_t int_status;
-		uint32_t int_enabled;
+		std::atomic_uint32_t int_status; // accessed from pfifo::worker with pmc::update_irq()
+		std::atomic_uint32_t int_enabled; // accessed from pfifo::worker with pmc::update_irq()
 		uint32_t engine_enabled;
 	};
 };
diff --git a/src/hw/video/gpu/ptimer.hpp b/src/hw/video/gpu/ptimer.hpp
index 8db2810..3e6a52a 100644
--- a/src/hw/video/gpu/ptimer.hpp
+++ b/src/hw/video/gpu/ptimer.hpp
@@ -5,6 +5,7 @@
 #pragma once
 
 #include <cstdint>
+#include <atomic>
 #include "nv2a_defs.hpp"
 
 #define NV_PTIMER 0x00009000
@@ -64,8 +65,8 @@ class ptimer {
 	// Counter value when it was stopped
 	uint64_t counter_when_stopped;
 	struct {
-		uint32_t int_status;
-		uint32_t int_enabled;
+		std::atomic_uint32_t int_status; // accessed from pfifo::worker with pmc::update_irq()
+		std::atomic_uint32_t int_enabled; // accessed from pfifo::worker with pmc::update_irq()
 		uint32_t multiplier, divider;
 		uint32_t alarm;
 	};