Merge branch 'isr-refactor'

examples/template/src/main.c

@@ -1,9 +1,7 @@
-#include <seven/version.h>
 #include <seven/hw/video/prelude.h>
 #include <seven/hw/video/bg_bitmap.h>
 #include <seven/hw/video/color_constants.h>
 
-libsevenEmitVersionString();
 
 int main(void)
 {

examples/vsync/src/main.c

@@ -12,11 +12,12 @@ int main(void)
 {
  // Set up the necessary interrupt handling
  irqInitDefault();
- irqEnableFull(IRQ_VBLANK);
+ irqEnable(IRQ_VBLANK);
  irqHandlerSet(IRQ_VBLANK, vblank_callback);
 
  // Clear the force-blank bit
  REG_DISPCNT = 0;
+ REG_DISPSTAT = LCD_VBLANK_IRQ_ENABLE;
 
  while (1)
  {

libseven/include/seven/attributes.h

@@ -8,33 +8,26 @@
 
 #include <seven/base.h>
 
-#define _LIBSEVEN_SECCOUNT  _LIBSEVEN_STR2(__COUNTER__)
+#define _LIBSEVEN_COUNTER _LIBSEVEN_STR2(__COUNTER__)
 
-#define PACKED __attribute__((__packed__))
-#define ALIGN(n) __attribute__((__aligned__(n)))
-#define NORETURN __attribute__((__noreturn__))
-#define NOINLINE __attribute__((__noinline__))
-#define ARM_CODE __attribute__((__target__("arm"))) NOINLINE
-#define THUMB_CODE __attribute__((__target__("thumb"))) NOINLINE
+#define ALIGN(n) __attribute__((__aligned__(n)))
+#define ARM_CODE __attribute__((__target__("arm"))) NOINLINE
+#define NOINLINE __attribute__((__noinline__))
+#define NORETURN __attribute__((__noreturn__))
+#define PACKED __attribute__((__packed__))
+#define SECTION(name) __attribute__((__section__(name)))
+#define THUMB_CODE __attribute__((__target__("thumb"))) NOINLINE
 
-#define SECTION(name) __attribute__((__section__(name)))
+#define IWRAM_CODE SECTION(".iwram.text." _LIBSEVEN_COUNTER) NOINLINE
+#define IWRAM_DATA SECTION(".iwram.data." _LIBSEVEN_COUNTER)
 
-#define IWRAM_SECTION(suffix) SECTION(".iwram" suffix)
-#define IWRAM_OVERLAY(number) SECTION(".iwram" #number)
+#define EWRAM_CODE  SECTION(".ewram.text." _LIBSEVEN_COUNTER) NOINLINE
+#define EWRAM_DATA  SECTION(".ewram.data." _LIBSEVEN_COUNTER)
 
-#define IWRAM_CODE IWRAM_SECTION(".text." _LIBSEVEN_SECCOUNT) NOINLINE
-#define IWRAM_DATA IWRAM_SECTION(".data." _LIBSEVEN_SECCOUNT)
-
-#define EWRAM_SECTION(suffix) SECTION(".ewram" suffix)
-#define EWRAM_OVERLAY(number) SECTION(".ewram" #number)
-
-#define EWRAM_CODE EWRAM_SECTION(".text." _LIBSEVEN_SECCOUNT) NOINLINE
-#define EWRAM_DATA EWRAM_SECTION(".data." _LIBSEVEN_SECCOUNT)
-
-#ifndef _LIBSEVEN_NOCOMPATIBLE
- #define IWRAM_BSS SECTION(".bss." _LIBSEVEN_SECCOUNT)
- #define EWRAM_BSS SECTION(".sbss." _LIBSEVEN_SECCOUNT)
+#ifdef LIBSEVEN_COMPATIBLE
+ #define IWRAM_BSS SECTION(".bss." _LIBSEVEN_COUNTER)
+ #define EWRAM_BSS SECTION(".sbss." _LIBSEVEN_COUNTER)
 #else
- #define IWRAM_BSS  SECTION(".iwram_bss." _LIBSEVEN_SECCOUNT)
- #define EWRAM_BSS  SECTION(".ewram_bss." _LIBSEVEN_SECCOUNT)
-#endif /* !_LIBSEVEN_NOCOMPATIBLE */
+ #define IWRAM_BSS SECTION(".iwram_bss." _LIBSEVEN_COUNTER)
+ #define EWRAM_BSS SECTION(".ewram_bss." _LIBSEVEN_COUNTER)
+#endif /* LIBSEVEN_COMPATIBLE */

libseven/include/seven/base.h

@@ -21,12 +21,14 @@
 #define _LIBSEVEN_STR(s) #s
 #define _LIBSEVEN_STR2(s) _LIBSEVEN_STR(s)
 
+#define _LIBSEVEN_TARGET_ARM __attribute__((__target__("arm"), __noinline__))
+#define _LIBSEVEN_NOINLINE __attribute__((__noinline__))
 #define _LIBSEVEN_NORETURN __attribute__((__noreturn__))
-#define _LIBSEVEN_ALIGN4 __attribute__((__aligned__(4)))
+#define _LIBSEVEN_ALIGNED __attribute__((__aligned__(4)))
 
 #define LIBSEVEN_VERSION_MAJOR 0
-#define LIBSEVEN_VERSION_MINOR 17
-#define LIBSEVEN_VERSION_PATCH 2
+#define LIBSEVEN_VERSION_MINOR 18
+#define LIBSEVEN_VERSION_PATCH 0
 
 #define LIBSEVEN_VERSION \
  _LIBSEVEN_STR2(LIBSEVEN_VERSION_MAJOR) "." \

libseven/include/seven/hw/irq.h

@@ -10,10 +10,6 @@
 
 _LIBSEVEN_EXTERN_C
 
-// Attribute for compiling functions in a way that is suitable for ISRs.
-//
-#define ISR_FUNCTION IWRAM_CODE ARM_CODE
-
 // Interrupt Enable
 //
 #define REG_IE VOLADDR(0x04000200, uint16_t)
@@ -28,11 +24,14 @@ _LIBSEVEN_EXTERN_C
 
 // Interrupt Service Routine Function Pointer
 //
-#define MEM_ISR MEMADDR(0x03FFFFFC, IsrFn*)
+#define MEM_ISR VOLADDR(0x03FFFFFC, IsrFn*)
+
+// Interrupt Flags used by BIOS
+#define MEM_IFBIOS VOLADDR(0x03FFFFF8, uint16_t)
 
 // IRQ bitflags
 //
-enum IRQ
+enum IRQFlag
 {
  IRQ_VBLANK = BIT(0),
  IRQ_HBLANK = BIT(1),
@@ -57,7 +56,7 @@ enum IRQGroup
  IRQS_BLANK = IRQ_VBLANK | IRQ_HBLANK,
  IRQS_TIMER = IRQ_TIMER_0 | IRQ_TIMER_1 | IRQ_TIMER_2 | IRQ_TIMER_3,
  IRQS_DMA = IRQ_DMA_0 | IRQ_DMA_1 | IRQ_DMA_2 | IRQ_DMA_3,
- // IRQs in this group can wake up the GBA from a svcStop() call.
+ // IRQs in this group can wake up the GBA from biosStop().
  IRQS_EXTERNAL = IRQ_SERIAL | IRQ_KEYPAD | IRQ_CARTRIDGE,
  IRQS_ALL = BITS(14),
 };
@@ -101,17 +100,13 @@ extern void irqInit(IsrFn *isr);
 // Initialize interrupt handling using a handler system.
 //
 // Used with the irqHandler* functions.
+// Supports nesting by calling irqUnmask() inside a handler.
 extern void irqInitDefault(void);
 
-// Initialize interrupt handling using a single handler function.
+// Initialize interrupt handling using an optional, single handler function.
 //
-extern void irqInitSimple(IrqHandlerFn *fn);
-
-// Initialize interrupt handling using a stub handler
-// that only acknowledges the IRQs and returns.
-//
-// This is enough for the BIOS interrupt wait functions to work.
-extern void irqInitStub(void);
+// Does not support nesting by default.
+extern void irqInitMinimal(IrqHandlerFn *fn);
 
 // Set the handler associated with the specified irq.
 //
@@ -138,17 +133,16 @@ extern uint16_t irqEnable(uint16_t irqs);
 // Returns the old value of the IE register.
 extern uint16_t irqDisable(uint16_t irqs);
 
-// Enable the specified IRQs and IRQ enable bits in the respective IO registers.
-//
-// Returns the old value of the IE register.
-extern uint16_t irqEnableFull(uint16_t irqs);
+// Calls a function with IRQs disabled, passing data as an argument.
+extern void irqFree(void (*f)(void *), void *arg);
 
-// Disable the specified IRQs and IRQ enable bits in the respective IO registers.
-//
-// Returns the old value of the IE register.
-extern uint16_t irqDisableFull(uint16_t irqs);
+// Mask IRQs at the CPU level.
+extern void irqMask(void);
 
-// Calls a function with IRQs disabled, passing data as an argument.
-extern void irqFree(void (*f)(void*), void *arg);
+// Unmask IRQs at the CPU level. Used for enabling nested interrupts.
+extern void irqUnmask(void);
+
+// Returns whether IRQs are masked at the CPU level.
+extern bool irqMasked(void);
 
 _LIBSEVEN_EXTERN_C_END

libseven/include/seven/hw/video/types.h

@@ -23,14 +23,14 @@ struct Matrix
  int16_t vdx; // vertical shearing factor
  int16_t hdy; // horizontal shearing factor
  int16_t vdy; // vertical scaling factor
-} _LIBSEVEN_ALIGN4;
+} _LIBSEVEN_ALIGNED;
 
 struct Object
 {
  uint16_t attr0;
  uint16_t attr1;
  uint16_t attr2;
  uint16_t _reserved;
-} _LIBSEVEN_ALIGN4;
+} _LIBSEVEN_ALIGNED;
 
 _LIBSEVEN_EXTERN_C_END

libseven/include/seven/types.h

@@ -66,7 +66,7 @@ typedef uintptr_t uptr;
 #define USIZE_BITS (CHAR_BIT * sizeof(usize))
 #define UPTR_BITS (CHAR_BIT * sizeof(uptr))
 
-#ifndef _LIBSEVEN_NOCOMPATIBLE
+#ifdef LIBSEVEN_COMPATIBLE
 
 typedef i8 s8;
 typedef i16 s16;
@@ -96,4 +96,4 @@ typedef iptr sptr;
 #define SSIZE_BITS ISIZE_BITS
 #define SPTR_BITS IPTR_BITS
 
-#endif /* !_LIBSEVEN_NOCOMPATIBLE */
+#endif /* LIBSEVEN_COMPATIBLE */

libseven/src/hw/irq.c

@@ -8,11 +8,18 @@
 #include <seven/hw/irq.h>
 
 extern IsrFn isrDefault;
-extern IsrFn isrSimple;
-extern IsrFn isrStub;
-
-extern IrqHandlerFn* ISR_SIMPLE_HANDLER;
-extern IrqHandlerFn* ISR_DEFAULT_HANDLERS[16];
+extern IsrFn isrMinimal;
+
+// Mark these as volatile because LTO cannot verify that isrDefault/isrMinimal
+// is called because it's invoked indirectly through the hardware.
+//
+// This means LTO will consider calls to irqSetHandler and similar to be dead
+// accesses, and remove them entirely
+//
+// For our purposes, writing these does produce a side effect, so volatile is
+// actually the semantically correct option here.
+extern IrqHandlerFn * volatile ISR_MINIMAL_HANDLER;
+extern IrqHandlerFn * volatile ISR_DEFAULT_HANDLERS[16];
 
 extern void irqInit(IsrFn *isr)
 {
@@ -23,7 +30,6 @@ extern void irqInit(IsrFn *isr)
  MEM_ISR = isr;
 
  REG_IME = 1;
- return;
 }
 
 extern void irqInitDefault(void)
@@ -38,18 +44,13 @@ extern void irqInitDefault(void)
  irqInit(isrDefault);
 }
 
-extern void irqInitSimple(IrqHandlerFn *handler)
+extern void irqInitMinimal(IrqHandlerFn *handler)
 {
  REG_IME = 0;
 
- ISR_SIMPLE_HANDLER = handler;
-
- irqInit(isrSimple);
-}
+ ISR_MINIMAL_HANDLER = handler;
 
-extern void irqInitStub(void)
-{
- irqInit(isrStub);
+ irqInit(isrMinimal);
 }
 
 extern bool irqHandlerSet(uint16_t irq, IrqHandlerFn *fn)
@@ -118,14 +119,49 @@ extern uint16_t irqDisable(uint16_t irqs)
  return old;
 }
 
-extern void irqFree(void (*f)(void*), void *arg)
+extern void irqFree(void (*f)(void *), void *arg)
 {
  uint32_t ime = REG_IME;
  REG_IME = 0;
 
  f(arg);
 
  REG_IME = ime;
+}
+
+_LIBSEVEN_TARGET_ARM extern void irqMask(void)
+{
+ __asm__ volatile
+ (
+ "mrs r0, cpsr\n"
+ "orr r0, r0, 0x80\n"
+ "msr cpsr_c, r0\n"
+ ::: "r0"
+ );
+}
+
+_LIBSEVEN_TARGET_ARM extern void irqUnmask(void)
+{
+ __asm__ volatile
+ (
+ "mrs r0, cpsr\n"
+ "bic r0, r0, 0x80\n"
+ "msr cpsr_c, r0\n"
+ ::: "r0"
+ );
+}
+
+_LIBSEVEN_TARGET_ARM extern bool irqMasked(void)
+{
+ bool masked;
+
+ __asm__ volatile
+ (
+ "mrs %0, cpsr\n"
+ "lsr %0, %0, 7\n"
+ "and %0, %0, 1\n"
+ : "=r"(masked)
+ );
 
- return;
+ return masked;
 }