From 84fa5389796f366dd6f098bef45a5f4bc6b17d8d Mon Sep 17 00:00:00 2001
From: Aidan MacDonald <amachronic@protonmail.com>
Date: Fri, 27 Feb 2026 20:33:06 +0000
Subject: [PATCH] echoplayer: add PCM debug menu

Display DMA error counters and the SAI underrun counter
in the debug menu.

Change-Id: I235bfcb0fa965d87c30deeb300535141eda5f974
---
 firmware/target/arm/stm32/debug-stm32h7.c     | 57 +++++++++++++++++++
 .../arm/stm32/echoplayer/pcm-echoplayer.c     | 27 +++++++++
 2 files changed, 84 insertions(+)

diff --git a/firmware/target/arm/stm32/debug-stm32h7.c b/firmware/target/arm/stm32/debug-stm32h7.c
index 99a3849b41..f8cd7200c3 100644
--- a/firmware/target/arm/stm32/debug-stm32h7.c
+++ b/firmware/target/arm/stm32/debug-stm32h7.c
@@ -86,11 +86,68 @@ static bool swd_menu(void)
     return simplelist_show_list(&info);
 }
 
+#if defined(ECHO_R1)
+extern volatile int pcm_sai_xrun_count;
+extern volatile int pcm_dma_teif_count;
+extern volatile int pcm_dma_dmeif_count;
+extern volatile int pcm_dma_feif_count;
+
+struct pcmdebug_counter
+{
+    const char *name;
+    volatile int *value;
+};
+
+static const struct pcmdebug_counter pcmdebug_counters[] =
+{
+    {"SAI xrun count",  &pcm_sai_xrun_count},
+    {"DMA TEIF count",  &pcm_dma_teif_count},
+    {"DMA DMEIF count", &pcm_dma_dmeif_count},
+    {"DMA FEIF count",  &pcm_dma_feif_count},
+};
+
+static int pcmdebug_menu_action_cb(int action, struct gui_synclist *lists)
+{
+    if (action == ACTION_STD_OK)
+    {
+        int item = gui_synclist_get_sel_pos(lists);
+        const struct pcmdebug_counter *counter = &pcmdebug_counters[item];
+
+        *counter->value = 0;
+        action = ACTION_REDRAW;
+    }
+
+    if (action == ACTION_NONE)
+        action = ACTION_REDRAW;
+
+    return action;
+}
+
+static const char *pcmdebug_menu_get_name(int item, void *data, char *buf, size_t bufsz)
+{
+    const struct pcmdebug_counter *counter = &pcmdebug_counters[item];
+    (void)data;
+
+    snprintf(buf, bufsz, "%s: %d", counter->name, *counter->value);
+    return buf;
+}
+
+static bool pcm_debug_menu(void)
+{
+    struct simplelist_info info;
+    simplelist_info_init(&info, "PCM debug", ARRAYLEN(pcmdebug_counters), NULL);
+    info.action_callback = pcmdebug_menu_action_cb;
+    info.get_name = pcmdebug_menu_get_name;
+    return simplelist_show_list(&info);
+}
+#endif
+
 /* Menu definition */
 static const struct {
     const char *name;
     bool (*function) (void);
 } menuitems[] = {
+    {"PCM debug", pcm_debug_menu},
     {"SWD/JTAG", swd_menu},
 };
 
diff --git a/firmware/target/arm/stm32/echoplayer/pcm-echoplayer.c b/firmware/target/arm/stm32/echoplayer/pcm-echoplayer.c
index d85acad377..c1d457ef8d 100644
--- a/firmware/target/arm/stm32/echoplayer/pcm-echoplayer.c
+++ b/firmware/target/arm/stm32/echoplayer/pcm-echoplayer.c
@@ -65,6 +65,11 @@ static volatile int play_active;
 
 static int pcm_last_freq = -1;
 
+volatile int pcm_sai_xrun_count;
+volatile int pcm_dma_teif_count;
+volatile int pcm_dma_dmeif_count;
+volatile int pcm_dma_feif_count;
+
 static void play_dma_start(const void *addr, size_t size)
 {
     commit_dcache_range(addr, size);
@@ -151,8 +156,12 @@ static void sai_init(void)
                 SLOTSZ_V(DATASZ),               /* slot size = data size */
                 FBOFF(0));                      /* no bit offset in slot */
 
+    /* Enable xrun error interrupt */
+    reg_writelf(sai1a, SAI_SUBBLOCK_IM, OVRUDR(1));
+
     /* Enable interrupts in NVIC */
     nvic_enable_irq(NVIC_IRQN_DMA1_STR0);
+    nvic_enable_irq(NVIC_IRQN_SAI1);
 }
 
 struct div_settings
@@ -326,6 +335,15 @@ void dma1_ch0_irq_handler(void)
     const void *addr;
     size_t size;
 
+    if (reg_vreadf(lisr, DMA_LISR, TEIF0))
+        pcm_dma_teif_count++;
+
+    if (reg_vreadf(lisr, DMA_LISR, DMEIF0))
+        pcm_dma_dmeif_count++;
+
+    if (reg_vreadf(lisr, DMA_LISR, FEIF0))
+        pcm_dma_feif_count++;
+
     if (reg_vreadf(lisr, DMA_LISR, TEIF0) ||
         reg_vreadf(lisr, DMA_LISR, DMEIF0) ||
         reg_vreadf(lisr, DMA_LISR, FEIF0))
@@ -352,3 +370,12 @@ void dma1_ch0_irq_handler(void)
         panicf("%s: %08lx", __func__, lisr);
     }
 }
+
+void sai1_irq_handler(void)
+{
+    if (reg_readlf(sai1a, SAI_SUBBLOCK_SR, OVRUDR))
+    {
+        reg_assignlf(sai1a, SAI_SUBBLOCK_CLRFR, OVRUDR(1));
+        pcm_sai_xrun_count++;
+    }
+}