Fixes to decouple interrupt for dual-issue compatibility purposes.

module_usb_audio/usb_buffer/decouple.xc

@@ -648,7 +648,7 @@ void decouple(chanend c_mix_out
     }
 #endif
 
-    set_interrupt_handler(handle_audio_request, 200, 1, c_mix_out, 0);
+    set_interrupt_handler(handle_audio_request, 1, c_mix_out, 0);
 
     /* Wait for usb_buffer() to set up globals for us to use
      * Note: assumed that buffer_aud_ctl_chan is also setup before these globals are !0 */

module_usb_audio/usb_buffer/decouple_interrupt.c

@@ -0,0 +1,3 @@
+#include <interrupt.h>
+
+register_interrupt_handler(handle_audio_request, 1, 200)

module_usb_audio/usb_buffer/interrupt.h

@@ -143,10 +143,19 @@
 
 //int ksp_enter, ksp_exit, r11_store;
 
+#ifdef __XS2A__
+#define ISSUE_MODE_SINGLE ".issue_mode single\n"
+#define ISSUE_MODE_DUAL ".issue_mode dual\n"
+#else
+#define ISSUE_MODE_SINGLE
+#define ISSUE_MODE_DUAL
+#endif
+
 #define do_interrupt_handler(f,args)    \
-  asm("bu .L__" #f "_handler_skip;\n" \
+  asm(ISSUE_MODE_SINGLE\
       ".align 4\n" \
       "__" #f "_handler:\n"  \
+      "ENTSP_lu6 0\n" \
       "kentsp " #args " + 19\n" \
       "__kent:" \
       save_state(f,args)    \
@@ -155,19 +164,24 @@
       restore_state(f,args)       \
       "krestsp " #args " + 19 \n" \
       "__kret:\n" \
-      "kret\n" \
-      ".L__" #f "_handler_skip:\n");
+      "kret\n");
 
-#define set_interrupt_handler(f, nstackwords, args, c, ...) \
-  asm (" .section .dp.data,       \"adw\", @progbits\n" \
-       " .align 8\n" \
-       "__" #f "_kernel_stack%=:\n" \
+#define register_interrupt_handler(f, args, nstackwords) \
+  asm (" .section .dp.data,       \"adw\", @progbits\n"  \
+       " .globl __" #f "_kernel_stack_end\n" \
+       " .globl __" #f "_handler\n" \
+       " .align 8\n"                                    \
+       "__" #f "_kernel_stack:\n" \
        " .space  " #nstackwords ", 0\n" \
-       " .text\n" \
-       "mov r10, %0; ldaw r11, dp[__" #f "_kernel_stack%=];add r11, r11, r10;ldaw r10, sp[0]; "\
-       "set sp,r11;stw r10, sp[0]; krestsp 0"::"r"(nstackwords-8):"r10","r11"); \
+       "__" #f "_kernel_stack_end:\n" \
+       " .space 2\n"\
+       " .text\n");                             \
+      do_interrupt_handler(f, args)
+
+#define set_interrupt_handler(f, args, c, ...) \
+  asm("ldaw r11, dp[__" #f "_kernel_stack_end];ldaw r10, sp[0]; " \
+      "set sp,r11;stw r10, sp[0]; krestsp 0":::"r10","r11");      \
   store_args ## args(c, __VA_ARGS__) \
-  do_interrupt_handler(f, args) \
   asm("ldap r11, __" #f "_handler; setv res[%0],r11"::"r"(c):"r11");    \
   asm("setc res[%0], 0xa; eeu res[%0]"::"r"(c));                        \
   asm("setsr (((0) & ~(((1 << 0x1) - 1) << 0x1)) | (((1) << 0x1) & (((1 << 0x1) - 1) << 0x1)))");