From fb46bb360872cd9ffec17cf7ebc83690962e7006 Mon Sep 17 00:00:00 2001
From: Ian Scott <ian@polpo.org>
Date: Sat, 6 Jul 2024 00:31:24 -0600
Subject: [PATCH] Dynamic PIC timers

---
 sw/CMakeLists.txt |  9 ++++++---
 sw/pico_pic.c     | 14 +++++++++-----
 sw/pico_pic.h     | 28 +++++++++++++++++++++-------
 3 files changed, 36 insertions(+), 15 deletions(-)

diff --git a/sw/CMakeLists.txt b/sw/CMakeLists.txt
index b5e6726..9ff20b0 100644
--- a/sw/CMakeLists.txt
+++ b/sw/CMakeLists.txt
@@ -113,6 +113,11 @@ function(config_target TARGET_NAME MULTIFW)
         # USB Mouse stuff
         target_include_directories(${TARGET_NAME} PUBLIC ${CMAKE_CURRENT_LIST_DIR}/mouse)
         target_compile_definitions(${TARGET_NAME} PRIVATE USB_MOUSE=1)
+        target_sources(${TARGET_NAME} PRIVATE
+            mouse/8250uart.cpp
+            mouse/sermouse.cpp
+            pico_pic.c
+        )
     endif()
 
     target_sources(${TARGET_NAME} PRIVATE M62429/M62429.cpp)
@@ -296,8 +301,6 @@ function(build_usb TARGET_NAME MULTIFW)
     target_sources(${TARGET_NAME} PRIVATE
         usbplay.cpp
         pico_pic.c
-        mouse/8250uart.cpp
-        mouse/sermouse.cpp
     )
     pico_enable_stdio_uart(${TARGET_NAME} 1)
     pico_enable_stdio_usb(${TARGET_NAME} 0)
@@ -412,7 +415,7 @@ elseif(PROJECT_TYPE STREQUAL "SB")
     build_sb(pg-sb FALSE)
 elseif(PROJECT_TYPE STREQUAL "ADLIB")
     set(FW_TARGET pg-adlib)
-    build_sb(pg-adlib FALSE)
+    build_adlib(pg-adlib FALSE)
 elseif(PROJECT_TYPE STREQUAL "MPU")
     set(FW_TARGET pg-mpu)
     build_mpu(pg-mpu FALSE)
diff --git a/sw/pico_pic.c b/sw/pico_pic.c
index a34bed2..b77ded7 100644
--- a/sw/pico_pic.c
+++ b/sw/pico_pic.c
@@ -4,8 +4,12 @@
 
 #include <stdio.h>
 
-// A fixed pool of only 3 events for now. gus-x only has 3 different timer events - two timers and one DMA
-PIC_TimerEvent timerEvents[4];
+// A fixed pool of multiple events.
+// gus-x has 3 different timer events - two timers and one DMA
+// 8250uart has 3
+// mpu401 has 3
+// SB has 1
+PIC_TimerEvent timerEvents[PIC_MAX_TIMERS];
 
 alarm_pool_t* alarm_pool;
 
@@ -44,7 +48,7 @@ int64_t PIC_HandleEvent(alarm_id_t id, void *user_data) {
 
 void PIC_RemoveEvents(PIC_EventHandler handler) {
     // puts("removeevents");
-    for (int i = 0; i < 4; ++i) {
+    for (int i = 0; i < PIC_MAX_TIMERS; ++i) {
         if (timerEvents[i].handler == handler) {
 #ifdef USE_ALARM
             if (timerEvents[i].alarm_id) {
@@ -63,12 +67,12 @@ void PIC_Init() {
 #ifdef USE_ALARM
     alarm_pool = alarm_pool_create(2, PICO_TIME_DEFAULT_ALARM_POOL_MAX_TIMERS);
     irq_set_priority(TIMER_IRQ_2, PICO_HIGHEST_IRQ_PRIORITY);
-    for (int i = 0; i < 4; ++i) {
+    for (int i = 0; i < PIC_MAX_TIMERS; ++i) {
         timerEvents[i].alarm_id = 0;
         timerEvents[i].handler = 0;
     }
 #else
-    for (int i = 0; i < 3; ++i) {
+    for (int i = 0; i < PIC_MAX_TIMERS; ++i) {
         timerEvents[i].active = false;
         timerEvents[i].deadline = UINT32_MAX;
         timerEvents[i].handler = 0;
diff --git a/sw/pico_pic.h b/sw/pico_pic.h
index 03927a9..ddc41f3 100644
--- a/sw/pico_pic.h
+++ b/sw/pico_pic.h
@@ -30,7 +30,8 @@ typedef struct {
 #endif
 } PIC_TimerEvent;
 
-extern PIC_TimerEvent timerEvents[4];
+#define PIC_MAX_TIMERS 8
+extern PIC_TimerEvent timerEvents[PIC_MAX_TIMERS];
 
 extern alarm_pool_t* alarm_pool;
 
@@ -52,15 +53,28 @@ static __force_inline void PIC_DeActivateIRQ(void) {
 
 static __force_inline void PIC_AddEvent(PIC_EventHandler handler, uint32_t delay, Bitu val) {
     // printf("add event: %x %x %d\n", handler, val, delay);
-    timerEvents[val].handler = handler;
-    timerEvents[val].value = val;
+    // find free slot - TBD if this is too jittery
+    int i;
+    for (i = 0; i < PIC_MAX_TIMERS; ++i) {
+        if (
+#ifdef USE_ALARM
+            !timerEvents[i].alarm_id
+#else
+            !timerEvents[i].active
+#endif
+        ) {
+            break;
+        }
+    }
+    timerEvents[i].handler = handler;
+    timerEvents[i].value = val;
 #ifdef USE_ALARM
     // timerEvents[val].alarm_id = add_alarm_in_us(delay, PIC_HandleEvent, timerEvents + val, true);
     // alarm_pool_cancel_alarm(alarm_pool, timerEvents[val].alarm_id);
-    timerEvents[val].alarm_id = alarm_pool_add_alarm_in_us(alarm_pool, delay, PIC_HandleEvent, timerEvents + val, true);
+    timerEvents[i].alarm_id = alarm_pool_add_alarm_in_us(alarm_pool, delay, PIC_HandleEvent, timerEvents + i, true);
 #else
-    timerEvents[val].deadline = time_us_32() + delay;
-    timerEvents[val].active = true;
+    timerEvents[i].deadline = time_us_32() + delay;
+    timerEvents[i].active = true;
 #endif
     // gpio_put(PICO_DEFAULT_LED_PIN, 1);
 }
@@ -71,7 +85,7 @@ void PIC_Init(void);
 
 #ifndef USE_ALARM
 static __force_inline void PIC_HandleEvents() {
-    for (int i = 0; i < 4; ++i) {
+    for (int i = 0; i < PIC_MAX_TIMERS; ++i) {
         if (timerEvents[i].active && timerEvents[i].deadline <= time_us_32()) {
             PIC_HandleEvent(0, &timerEvents[i]);
         }