software/videomixer: interrupt-driven video passthrough

software/include/hw/flags.h

@@ -30,4 +30,8 @@
 #define DVISAMPLER_DELAY_INC	0x4
 #define DVISAMPLER_DELAY_DEC	0x8
 
+#define DVISAMPLER_SLOT_EMPTY	0
+#define DVISAMPLER_SLOT_LOADED	1
+#define DVISAMPLER_SLOT_PENDING	2
+
 #endif /* __HW_FLAGS_H */

software/videomixer/isr.c

@@ -2,6 +2,8 @@
 #include <irq.h>
 #include <uart.h>
 
+void dvisampler0_isr(void); // FIXME
+
 void isr(void);
 void isr(void)
 {
@@ -11,4 +13,6 @@ void isr(void)
 	
 	if(irqs & (1 << UART_INTERRUPT))
 		uart_isr();
+	if(irqs & (1 << DVISAMPLER0_INTERRUPT))
+		dvisampler0_isr();
 }

software/videomixer/main.c

@@ -7,12 +7,11 @@
 #include <hw/csr.h>
 #include <hw/flags.h>
 
-static int d0, d1, d2;
+static int dvisampler0_d0, dvisampler0_d1, dvisampler0_d2;
-static unsigned int framebuffer[640*480] __attribute__((aligned(16)));
 
 static void print_status(void)
 {
-	printf("Ph: %4d %4d %4d // %d%d%d [%d %d %d] // %d // %dx%d\n", d0, d1, d2,
+	printf("dvisampler0 ph: %4d %4d %4d // %d%d%d [%d %d %d] // %d // %dx%d\n", dvisampler0_d0, dvisampler0_d1, dvisampler0_d2,
 		dvisampler0_data0_charsync_char_synced_read(),
 		dvisampler0_data1_charsync_char_synced_read(),
 		dvisampler0_data2_charsync_char_synced_read(),
@@ -24,17 +23,6 @@ static void print_status(void)
 		dvisampler0_resdetection_vres_read());
 }
 
-static void capture_fb(void)
-{
-	dvisampler0_dma_frame_size_write(sizeof(framebuffer));
-	dvisampler0_dma_slot0_address_write((unsigned int)framebuffer);
-	dvisampler0_dma_slot0_status_write(1);
-
-	printf("waiting for DMA...");
-	while(dvisampler0_dma_slot0_status_read() != 2);
-	printf("done\n");
-}
-
 static void calibrate_delays(void)
 {
 	dvisampler0_data0_cap_dly_ctl_write(DVISAMPLER_DELAY_CAL);
@@ -49,7 +37,7 @@ static void calibrate_delays(void)
 	dvisampler0_data0_cap_phase_reset_write(1);
 	dvisampler0_data1_cap_phase_reset_write(1);
 	dvisampler0_data2_cap_phase_reset_write(1);
-	d0 = d1 = d2 = 0;
+	dvisampler0_d0 = dvisampler0_d1 = dvisampler0_d2 = 0;
 	printf("Delays calibrated\n");
 }
 
@@ -58,36 +46,36 @@ static void adjust_phase(void)
 	switch(dvisampler0_data0_cap_phase_read()) {
 		case DVISAMPLER_TOO_LATE:
 			dvisampler0_data0_cap_dly_ctl_write(DVISAMPLER_DELAY_DEC);
-			d0--;
+			dvisampler0_d0--;
 			dvisampler0_data0_cap_phase_reset_write(1);
 			break;
 		case DVISAMPLER_TOO_EARLY:
 			dvisampler0_data0_cap_dly_ctl_write(DVISAMPLER_DELAY_INC);
-			d0++;
+			dvisampler0_d0++;
 			dvisampler0_data0_cap_phase_reset_write(1);
 			break;
 	}
 	switch(dvisampler0_data1_cap_phase_read()) {
 		case DVISAMPLER_TOO_LATE:
 			dvisampler0_data1_cap_dly_ctl_write(DVISAMPLER_DELAY_DEC);
-			d1--;
+			dvisampler0_d1--;
 			dvisampler0_data1_cap_phase_reset_write(1);
 			break;
 		case DVISAMPLER_TOO_EARLY:
 			dvisampler0_data1_cap_dly_ctl_write(DVISAMPLER_DELAY_INC);
-			d1++;
+			dvisampler0_d1++;
 			dvisampler0_data1_cap_phase_reset_write(1);
 			break;
 	}
 	switch(dvisampler0_data2_cap_phase_read()) {
 		case DVISAMPLER_TOO_LATE:
 			dvisampler0_data2_cap_dly_ctl_write(DVISAMPLER_DELAY_DEC);
-			d2--;
+			dvisampler0_d2--;
 			dvisampler0_data2_cap_phase_reset_write(1);
 			break;
 		case DVISAMPLER_TOO_EARLY:
 			dvisampler0_data2_cap_dly_ctl_write(DVISAMPLER_DELAY_INC);
-			d2++;
+			dvisampler0_d2++;
 			dvisampler0_data2_cap_phase_reset_write(1);
 			break;
 	}
@@ -95,21 +83,73 @@ static void adjust_phase(void)
 
 static int init_phase(void)
 {
-	int od0, od1, od2; 
+	int o_d0, o_d1, o_d2; 
 	int i, j;
 
 	for(i=0;i<100;i++) {
-		od0 = d0;
+		o_d0 = dvisampler0_d0;
-		od1 = d1;
+		o_d1 = dvisampler0_d1;
-		od2 = d2;
+		o_d2 = dvisampler0_d2;
 		for(j=0;j<1000;j++)
 			adjust_phase();
-		if((abs(d0 - od0) < 4) && (abs(d1 - od1) < 4) && (abs(d2 - od2) < 4))
+		if((abs(dvisampler0_d0 - o_d0) < 4) && (abs(dvisampler0_d1 - o_d1) < 4) && (abs(dvisampler0_d2 - o_d2) < 4))
 			return 1;
 	}
 	return 0;
 }
 
+#define FRAMEBUFFER_COUNT 4
+#define FRAMEBUFFER_MASK (FRAMEBUFFER_COUNT - 1)
+
+static unsigned int dvisampler0_framebuffers[FRAMEBUFFER_COUNT][640*480] __attribute__((aligned(16)));
+static int dvisampler0_fb_slot_indexes[2];
+static int dvisampler0_next_fb_index;
+
+static void dvisampler0_init_video(void)
+{
+	unsigned int mask;
+
+	dvisampler0_dma_ev_pending_write(dvisampler0_dma_ev_pending_read());
+	dvisampler0_dma_ev_enable_write(0x3);
+	mask = irq_getmask();
+	mask |= 1 << DVISAMPLER0_INTERRUPT;
+	irq_setmask(mask);
+
+	dvisampler0_dma_frame_size_write(sizeof(dvisampler0_framebuffers[0]));
+	dvisampler0_fb_slot_indexes[0] = 0;
+	dvisampler0_dma_slot0_address_write((unsigned int)dvisampler0_framebuffers[0]);
+	dvisampler0_dma_slot0_status_write(DVISAMPLER_SLOT_LOADED);
+	dvisampler0_fb_slot_indexes[1] = 1;
+	dvisampler0_dma_slot1_address_write((unsigned int)dvisampler0_framebuffers[1]);
+	dvisampler0_dma_slot1_status_write(DVISAMPLER_SLOT_LOADED);
+	dvisampler0_next_fb_index = 2;
+
+	fb_base_write((unsigned int)dvisampler0_framebuffers[0]);
+}
+
+void dvisampler0_isr(void)
+{
+	int fb_index = -1;
+
+	if(dvisampler0_dma_slot0_status_read() == DVISAMPLER_SLOT_PENDING) {
+		fb_index = dvisampler0_fb_slot_indexes[0];
+		dvisampler0_fb_slot_indexes[0] = dvisampler0_next_fb_index;
+		dvisampler0_dma_slot0_address_write((unsigned int)dvisampler0_framebuffers[dvisampler0_next_fb_index]);
+		dvisampler0_dma_slot0_status_write(DVISAMPLER_SLOT_LOADED);
+		dvisampler0_next_fb_index = (dvisampler0_next_fb_index + 1) & FRAMEBUFFER_MASK;
+	}
+	if(dvisampler0_dma_slot1_status_read() == DVISAMPLER_SLOT_PENDING) {
+		fb_index = dvisampler0_fb_slot_indexes[1];
+		dvisampler0_fb_slot_indexes[1] = dvisampler0_next_fb_index;
+		dvisampler0_dma_slot1_address_write((unsigned int)dvisampler0_framebuffers[dvisampler0_next_fb_index]);
+		dvisampler0_dma_slot1_status_write(DVISAMPLER_SLOT_LOADED);
+		dvisampler0_next_fb_index = (dvisampler0_next_fb_index + 1) & FRAMEBUFFER_MASK;
+	}
+
+	if(fb_index != -1)
+		fb_base_write((unsigned int)dvisampler0_framebuffers[fb_index]);
+}
+
 static void vmix(void)
 {
 	unsigned int counter;
@@ -132,8 +172,6 @@ static void vmix(void)
 				adjust_phase();
 				counter = 0;
 			}
-			if(readchar_nonblock() && (readchar() == 'c'))
-				capture_fb();
 		}
 		printf("PLL unlocked\n");
 	}
@@ -147,7 +185,7 @@ int main(void)
 	
 	puts("Minimal video mixer software built "__DATE__" "__TIME__"\n");
 	
-	fb_base_write((unsigned int)framebuffer);
+	dvisampler0_init_video();
 	fb_enable_write(1);
 	vmix();