From 215465df74a6065f4b0fdf199b8b04454520a398 Mon Sep 17 00:00:00 2001 From: Bad Diode Date: Wed, 2 Jun 2021 20:20:23 +0200 Subject: Update the renderer to support a text layer --- src/gba/interrupts.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 src/gba/interrupts.c (limited to 'src/gba/interrupts.c') diff --git a/src/gba/interrupts.c b/src/gba/interrupts.c new file mode 100644 index 0000000..3b11335 --- /dev/null +++ b/src/gba/interrupts.c @@ -0,0 +1,91 @@ +#include "gba.h" + +IrsFunc irs_table[] = { + [IRQ_VBLANK ] = NULL, + [IRQ_HBLANK ] = NULL, + [IRQ_VCOUNT ] = NULL, + [IRQ_TIMER_0] = NULL, + [IRQ_TIMER_1] = NULL, + [IRQ_TIMER_2] = NULL, + [IRQ_TIMER_3] = NULL, + [IRQ_SERIAL ] = NULL, + [IRQ_DMA_0 ] = NULL, + [IRQ_DMA_1 ] = NULL, + [IRQ_DMA_2 ] = NULL, + [IRQ_DMA_3 ] = NULL, + [IRQ_KEYPAD ] = NULL, + [IRQ_GAMEPAK] = NULL, +}; + +// External irs_main function, has to be written in ARM assembly. +void irs_main(void); +#define IRS_MAIN *(IrsFunc*)(0x03007FFC) + +void +irq_enable(IrqIndex idx) { + switch (idx) { + case IRQ_VBLANK: { DISP_STATUS |= DISP_VBLANK_IRQ; } break; + case IRQ_HBLANK: { DISP_STATUS |= DISP_HBLANK_IRQ; } break; + case IRQ_VCOUNT: { DISP_STATUS |= DISP_VCOUNT_IRQ; } break; + case IRQ_TIMER_0: { TIMER_CTRL_0 |= TIMER_CTRL_IRQ; } break; + case IRQ_TIMER_1: { TIMER_CTRL_1 |= TIMER_CTRL_IRQ; } break; + case IRQ_TIMER_2: { TIMER_CTRL_2 |= TIMER_CTRL_IRQ; } break; + case IRQ_TIMER_3: { TIMER_CTRL_3 |= TIMER_CTRL_IRQ; } break; + case IRQ_SERIAL: { /* TODO: Set REG_SERIAL? */ } break; + case IRQ_DMA_0: { DMA_CTRL(0) |= DMA_IRQ; } break; + case IRQ_DMA_1: { DMA_CTRL(1) |= DMA_IRQ; } break; + case IRQ_DMA_2: { DMA_CTRL(2) |= DMA_IRQ; } break; + case IRQ_DMA_3: { DMA_CTRL(3) |= DMA_IRQ; } break; + case IRQ_KEYPAD: { KEY_CTRL |= KEY_IRQ; } break; + case IRQ_GAMEPAK: { /* Nothing to do here...*/ } break; + } + IRQ_ENABLE |= (1 << idx); +} + +void +irq_disable(IrqIndex idx) { + switch (idx) { + case IRQ_VBLANK: { DISP_STATUS &= ~DISP_VBLANK_IRQ; } break; + case IRQ_HBLANK: { DISP_STATUS &= ~DISP_HBLANK_IRQ; } break; + case IRQ_VCOUNT: { DISP_STATUS &= ~DISP_VCOUNT_IRQ; } break; + case IRQ_TIMER_0: { TIMER_CTRL_0 &= ~TIMER_CTRL_IRQ; } break; + case IRQ_TIMER_1: { TIMER_CTRL_1 &= ~TIMER_CTRL_IRQ; } break; + case IRQ_TIMER_2: { TIMER_CTRL_2 &= ~TIMER_CTRL_IRQ; } break; + case IRQ_TIMER_3: { TIMER_CTRL_3 &= ~TIMER_CTRL_IRQ; } break; + case IRQ_SERIAL: { /* TODO: Set REG_SERIAL? */ } break; + case IRQ_DMA_0: { DMA_CTRL(0) &= ~DMA_IRQ; } break; + case IRQ_DMA_1: { DMA_CTRL(1) &= ~DMA_IRQ; } break; + case IRQ_DMA_2: { DMA_CTRL(2) &= ~DMA_IRQ; } break; + case IRQ_DMA_3: { DMA_CTRL(3) &= ~DMA_IRQ; } break; + case IRQ_KEYPAD: { KEY_CTRL &= ~KEY_IRQ; } break; + case IRQ_GAMEPAK: { /* Nothing to do here...*/ } break; + } + IRQ_ENABLE &= ~(1 << idx); +} + +void +irs_set(IrqIndex idx, IrsFunc func) { + // Store IRQ_CTRL status and disable interrupts for now. + u16 irq_ctrl = IRQ_CTRL; + IRQ_CTRL = 0; + + // Update the IRS table and enable/disable the given IRQ. + irs_table[idx] = func; + if (func == NULL) { + irq_disable(idx); + } else { + irq_enable(idx); + } + + // Restore previous irq_ctrl. + IRQ_CTRL = irq_ctrl; +} + +void +irq_init(void) { + IRS_MAIN = irs_main; + IRQ_CTRL = 1; +} + +void +irs_stub(void) {} -- cgit v1.2.1