*-nemu,ioe: add audio

am/arch/platform/nemu.mk

@@ -4,6 +4,7 @@ AM_SRCS += nemu/common/trm.c \
            nemu/common/input.c \
            nemu/common/timer.c \
            nemu/common/video.c \
+           nemu/common/audio.c \
            dummy/mpe.c \
 
 CFLAGS  += -I$(AM_HOME)/am/src/nemu/include

am/src/nemu/common/audio.c

@@ -0,0 +1,70 @@
+#include <am.h>
+#include <amdev.h>
+#include <klib.h>
+#include <nemu.h>
+
+static uint8_t* const sbuf = (uint8_t *)AUDIO_SBUF_ADDR;
+static int sbuf_size = 0;
+static int head = 0;
+
+void __am_audio_init() {
+}
+
+static int audio_write(uint8_t *buf, int len) {
+  uint32_t count = inl(AUDIO_COUNT_ADDR);
+  int free = sbuf_size - count;
+  int nwrite = len;
+  if (free < len) nwrite = free;
+
+  if (nwrite + head < sbuf_size) {
+    memcpy(sbuf + head, buf, nwrite);
+    head += nwrite;
+  } else {
+    int first_cpy_len = sbuf_size - head;
+    memcpy(sbuf + head, buf, first_cpy_len);
+    memcpy(sbuf, buf + first_cpy_len, nwrite - first_cpy_len);
+    head = nwrite - first_cpy_len;
+  }
+  count += nwrite;
+  outl(AUDIO_COUNT_ADDR, count);
+  return nwrite;
+}
+
+size_t __am_audio_write(uintptr_t reg, void *buf, size_t size) {
+  switch (reg) {
+    case _DEVREG_AUDIO_INIT: {
+      _DEV_AUDIO_INIT_t *init = (_DEV_AUDIO_INIT_t *)buf;
+      outl(AUDIO_FREQ_ADDR, init->freq);
+      outl(AUDIO_CHANNELS_ADDR, init->channels);
+      outl(AUDIO_SAMPLES_ADDR, init->samples);
+      outl(AUDIO_SBUF_SIZE_ADDR, init->bufsize);
+      outl(AUDIO_INIT_ADDR, 1);
+      sbuf_size = init->bufsize;
+
+      head = 0;
+      return size;
+    }
+    case _DEVREG_AUDIO_SBCTRL: {
+      _DEV_AUDIO_SBCTRL_t *ctl = (_DEV_AUDIO_SBCTRL_t *)buf;
+      if (ctl->wait) {
+        assert(ctl->len <= sbuf_size);
+        while (sbuf_size - inl(AUDIO_COUNT_ADDR) < ctl->len);
+      }
+      ctl->len = audio_write(ctl->stream, ctl->len);
+      return size;
+    }
+  }
+  return 0;
+}
+
+size_t __am_audio_read(uintptr_t reg, void *buf, size_t size) {
+  switch (reg) {
+    case _DEVREG_AUDIO_SBSTAT: {
+      _DEV_AUDIO_SBSTAT_t *stat = (_DEV_AUDIO_SBSTAT_t *)buf;
+      stat->count = inl(AUDIO_COUNT_ADDR);
+      stat->bufsize = sbuf_size;
+      return size;
+    }
+  }
+  return 0;
+}

am/src/nemu/common/ioe.c

@@ -3,10 +3,12 @@
 
 void __am_vga_init();
 void __am_timer_init();
+void __am_audio_init();
 
 int _ioe_init() {
   __am_vga_init();
   __am_timer_init();
+  __am_audio_init();
   return 0;
 }
 
@@ -14,12 +16,15 @@ size_t __am_timer_read(uintptr_t reg, void *buf, size_t size);
 size_t __am_video_read(uintptr_t reg, void *buf, size_t size);
 size_t __am_video_write(uintptr_t reg, void *buf, size_t size);
 size_t __am_input_read(uintptr_t reg, void *buf, size_t size);
+size_t __am_audio_read(uintptr_t reg, void *buf, size_t size);
+size_t __am_audio_write(uintptr_t reg, void *buf, size_t size);
 
 size_t _io_read(uint32_t dev, uintptr_t reg, void *buf, size_t size) {
   switch (dev) {
     case _DEV_INPUT: return __am_input_read(reg, buf, size);
     case _DEV_TIMER: return __am_timer_read(reg, buf, size);
     case _DEV_VIDEO: return __am_video_read(reg, buf, size);
+    case _DEV_AUDIO: return __am_audio_read(reg, buf, size);
   }
   return 0;
 }
@@ -27,6 +32,7 @@ size_t _io_read(uint32_t dev, uintptr_t reg, void *buf, size_t size) {
 size_t _io_write(uint32_t dev, uintptr_t reg, void *buf, size_t size) {
   switch (dev) {
     case _DEV_VIDEO: return __am_video_write(reg, buf, size);
+    case _DEV_AUDIO: return __am_audio_write(reg, buf, size);
   }
   return 0;
 }

am/src/nemu/include/nemu.h

@@ -12,6 +12,13 @@
 # define SCREEN_ADDR  0x100
 # define SYNC_ADDR    0x104
 # define FB_ADDR      0xa0000000
+# define AUDIO_FREQ_ADDR      0x200
+# define AUDIO_CHANNELS_ADDR  0x204
+# define AUDIO_SAMPLES_ADDR   0x208
+# define AUDIO_SBUF_SIZE_ADDR 0x20c
+# define AUDIO_INIT_ADDR      0x210
+# define AUDIO_COUNT_ADDR     0x214
+# define AUDIO_SBUF_ADDR      0xa0800000
 #elif defined(__ARCH_RISCV64_NOOP) || defined(__ARCH_RISCV32_NOOP)
 # define KBD_ADDR     0x40900000
 # define RTC_ADDR     0x4800bff8
@@ -25,6 +32,13 @@
 # define SCREEN_ADDR  0xa1000100
 # define SYNC_ADDR    0xa1000104
 # define FB_ADDR      0xa0000000
+# define AUDIO_FREQ_ADDR      0xa1000200
+# define AUDIO_CHANNELS_ADDR  0xa1000204
+# define AUDIO_SAMPLES_ADDR   0xa1000208
+# define AUDIO_SBUF_SIZE_ADDR 0xa100020c
+# define AUDIO_INIT_ADDR      0xa1000210
+# define AUDIO_COUNT_ADDR     0xa1000214
+# define AUDIO_SBUF_ADDR      0xa0800000
 #endif
 
 #define MMIO_BASE 0xa0000000