test(prog_field): Update to reflect new findings.

progressive_field/Makefile

@@ -1,6 +1,6 @@
 EE_OBJS	= prog_field.o
 EE_BIN = prog_field.elf
-EE_LIBS = -lkernel -lgraph
+EE_LIBS = -lkernel
 
 all: $(EE_BIN)
 

progressive_field/README.md

@@ -1,29 +1,35 @@
 # Progressive Field
 
 ## Description
-Checks the behaviour of FIELD in the GS CSR register when the PCRT is set to progressive. 
+Checks the behaviour of FIELD(in CSR) when the CMOD(in SMODE1)
+and VFP(in SYNCHV) bits are changed.
 
 ## PCSX2 Behaviour
-FIELD would alternate, just as if the PCRT was set to interlaced.
+PCSX2 would swap FIELD unconditionally, this caused some progressive games to
+bounce.
 
-This caused some progressive games to bounce.
+After the original progressive hardware test, PCSX2 would look at the interlace bit of SMODE2.
+If the bit was not set (progressive), PCSX2 would set FIELD, otherwise it would swap.
+
+This was later found to be incorrect behaviour.
 
 ## Findings
-When the video mode is set to progressive, FIELD is set.
+The original finding determined that when the video mode is set to progressive, FIELD is set.
+
+
+Turns out, the SMODE2 interlace bit has no control over FIELD behaviour.
+
+The actual behaviour is determined by CMOD (bits 13 & 14 in SMODE1)
+and VFP (bottom bits in SYNCV)
+
+![img](https://i.imgur.com/dsFYHm5.jpg)
 
 ## Related PR(s) or Issue(s)
 https://github.com/PCSX2/pcsx2/pull/6256
 
+https://github.com/PCSX2/pcsx2/pull/6342
 ## Expected Results
 
-This 30 times:
-```
-FIELD Prev 2000 Field New 2000
-```
+When testing CMOD 1, odd VFPs should say `FIELD IS CHANGING`
 
-In the case that the PCRT mode was set to interlaced, the expected result would be this, 15 times:
-
-```
-FIELD Prev 0 Field New 2000
-FIELD Prev 2000 Field New 0
-```
+When testing CMOD 0, no matter the VFP, it should say `FIELD IS NOT CHANGING`

progressive_field/prog_field.c

@@ -1,68 +1,63 @@
 #include <kernel.h>
 #include <stdio.h>
-#include <graph.h>
-#include <draw.h>
-#include <gs_psm.h>
 
 #define INTC_STAT (*(volatile u32 *)0x1000F000)
 #define GSCSR (*(volatile u64 *)0x12001000)
+#define SYNCV (*(volatile u64 *)0x12000060)
+#define SMODE1 (*(volatile u64 *)0x12000010)
 
-void setup_gs()
+static inline void wait_intc_vsync()
 {
-	framebuffer_t fb;
-	fb.address = graph_vram_allocate(640, 448, GS_PSM_24, GRAPH_ALIGN_PAGE);
-	fb.psm = GS_PSM_24;
-	fb.width = 640;
-	fb.height = 480;
+	INTC_STAT = 0xC;
+	while (!(INTC_STAT & 0x8))
+		;
+}
 
-	graph_initialize(fb.address, fb.width, fb.height, fb.psm, 0, 0);
-	return;
+void test_gs_field()
+{
+	for (int i = 0; i <= 9; i++)
+	{
+		printf("    Checking VFP %d\n", i);
+
+		// Bottom bits of SYNCV are the VFP
+		SYNCV = 0xC7800003000000LL + i;
+
+		// Wait for two vsyncs here, otherwise our current_field could be
+		// wrong.
+		wait_intc_vsync();
+		wait_intc_vsync();
+
+		u32 current_field = GSCSR & 0x2000;
+
+		for (u32 j = 0; j < 5; j++)
+		{
+			wait_intc_vsync();
+			if (current_field != (GSCSR & 0x2000))
+			{
+				goto field_changed;
+			}
+		}
+
+		printf("        FIELD IS NOT CHANGING\n");
+		continue;
+	field_changed:
+		printf("        FIELD IS CHANGING\n");
+	}
 }
 
 int main(void)
 {
-	setup_gs();
+	wait_intc_vsync();
 
-	INTC_STAT = 0xC;
-	while (!(INTC_STAT & 0x8))
-	{
-	}
-
-	INTC_STAT = 0xC;
-	while (!(INTC_STAT & 0x8))
-	{
-	}
-	// Set the mode to progressive
-	graph_set_mode(GRAPH_MODE_NONINTERLACED, GRAPH_MODE_NTSC, 0, 0);
-
-	// Clear V-blank start and V-blank end interrupts
-	INTC_STAT = 0xC;
-	// Wait for V-blank end interrupt
-	while (!(INTC_STAT & 0x8))
-	{
-	}
-
-	// Enable the VSync interrupt
+	// Enable VSYNC event
 	GSCSR = 0x8;
 
-	for(int i = 0; i < 30; i++)
-	{
-		// Clear V-blank start and V-blank end interrupts
-		INTC_STAT = 0xC;
-
-		// Read FIELD
-		u32 start_odd = GSCSR & 0x2000;
-
-		// Wait for V-blank end interrupt
-		while (!(INTC_STAT & 0x8))
-		{
-		}
-
-		// Read FIELD again
-		u32 end_odd = GSCSR & 0x2000;
-
-		printf("FIELD Prev %x Field New %x\n", start_odd, end_odd);
-	}
+	printf("Checking FIELD when CMOD is set to 1\n");
+	SMODE1 |= (1 << 13);
+	test_gs_field();
+	printf("Checking FIELD when CMOD is set to 0\n");
+	SMODE1 &= ~(2 << 13);
+	test_gs_field();
 
 	SleepThread();
 }