From a91f03d56e75b7862c040f56951169697c9e75d3 Mon Sep 17 00:00:00 2001
From: Sorgelig <pour.garbage@gmail.com>
Date: Wed, 8 Feb 2023 20:47:35 +0800
Subject: [PATCH] Support for YC phase_inc override.

---
 cfg.cpp   | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 cfg.h     |  8 +++++++
 video.cpp | 24 +++++++++++++++++---
 yc.txt    | 14 ++++++++++++
 4 files changed, 110 insertions(+), 3 deletions(-)
 create mode 100644 yc.txt

diff --git a/cfg.cpp b/cfg.cpp
index 34ebdcf..19c1bb6 100644
--- a/cfg.cpp
+++ b/cfg.cpp
@@ -579,3 +579,70 @@ void cfg_print()
 	}
 	printf("--------------\n");
 }
+
+static int yc_parse_mode(char* buf, yc_mode *mode)
+{
+	int i = 0;
+	while (1)
+	{
+		if (buf[i] == '=' || CHAR_IS_SPACE(buf[i]))
+		{
+			buf[i] = 0;
+			break;
+		}
+		else if (!buf[i]) return 0;
+		i++;
+	}
+
+	i++;
+	while (buf[i] == '=' || CHAR_IS_SPACE(buf[i])) i++;
+	ini_parser_debugf("Got yc_mode '%s' with VALUE %s", buf, buf + i);
+
+	snprintf(mode->key, sizeof(mode->key), "%s", buf);
+	mode->phase_inc = strtoull(buf + i, 0, 0);
+	if (!mode->phase_inc)
+	{
+		printf("ERROR: cannot parse YC phase_inc: '%s'\n", buf + i);
+		return 0;
+	}
+
+	return 1;
+}
+
+void yc_parse(yc_mode *yc_table, int max)
+{
+	memset(yc_table, 0, max * sizeof(yc_mode));
+
+	static char line[INI_LINE_SIZE];
+	int eof;
+
+	memset(line, 0, sizeof(line));
+	memset(&ini_file, 0, sizeof(ini_file));
+
+	const char *corename = user_io_get_core_name(1);
+	int corename_len = strlen(corename);
+
+	const char *name = "yc.txt";
+	if (!FileOpen(&ini_file, name))	return;
+
+	ini_parser_debugf("Opened file %s with size %llu bytes.", name, ini_file.size);
+
+	ini_pt = 0;
+	int n = 0;
+
+	while (n < max)
+	{
+		// get line
+		eof = ini_getline(line);
+		if (!strncasecmp(line, corename, corename_len))
+		{
+			int res = yc_parse_mode(line, &yc_table[n]);
+			if (res) n++;
+		}
+
+		// if end of file, stop
+		if (eof) break;
+	}
+
+	FileClose(&ini_file);
+}
diff --git a/cfg.h b/cfg.h
index 4bb4ea3..1805dfe 100644
--- a/cfg.h
+++ b/cfg.h
@@ -101,4 +101,12 @@ bool cfg_has_video_sections();
 void cfg_error(const char *fmt, ...);
 bool cfg_check_errors(char *msg, size_t max_len);
 
+struct yc_mode
+{
+	char key[64];
+	int64_t phase_inc;
+};
+
+void yc_parse(yc_mode *yc_table, int max);
+
 #endif // __CFG_H__
diff --git a/video.cpp b/video.cpp
index 15fd199..36b3828 100644
--- a/video.cpp
+++ b/video.cpp
@@ -77,6 +77,8 @@ static VideoInfo current_video_info;
 
 static int support_FHD = 0;
 
+yc_mode yc_modes[10];
+
 struct vrr_cap_t
 {
 	uint8_t active;
@@ -2394,6 +2396,8 @@ void video_cfg_reset()
 
 void video_init()
 {
+	yc_parse(yc_modes, sizeof(yc_modes) / sizeof(yc_modes[0]));
+
 	fb_init();
 	hdmi_config_init();
 	hdmi_config_set_hdr();
@@ -2725,7 +2729,8 @@ static void set_yc_mode()
 {
 	if (cfg.vga_mode_int >= 2)
 	{
-		int pal = (!current_video_info.vtime || (100000000 / current_video_info.vtime) < 55);
+		float fps = current_video_info.vtime ? (100000000.f / current_video_info.vtime) : 0.f;
+		int pal = fps < 55.f;
 		double CLK_REF = pal ? 4.43361875f : 3.579545f;
 		double CLK_VIDEO = current_video_info.ctime * 100.f / current_video_info.ptime;
 
@@ -2735,6 +2740,21 @@ static void set_yc_mode()
 		int COLORBURST_END = (int)(9.0f * (CLK_VIDEO / CLK_REF)) + COLORBURST_START;
 		int COLORBURST_RANGE = (COLORBURST_START << 10) | COLORBURST_END;
 
+		char yc_key[64];
+		sprintf(yc_key, "%s_%.1f%s", user_io_get_core_name(1), fps, current_video_info.interlaced ? "i" : "");
+
+		printf("Calculated YC parameters for '%s': %s PHASE_INC=%lld, COLORBURST_START=%d, COLORBURST_END=%d\n", yc_key, pal ? "PAL" : "NTSC", PHASE_INC, COLORBURST_START, COLORBURST_END);
+
+		for (uint i = 0; i < sizeof(yc_modes) / sizeof(yc_modes[0]); i++)
+		{
+			if (!strcasecmp(yc_modes[i].key, yc_key))
+			{
+				printf("Override YC PHASE_INC with value: %lld\n", yc_modes[i].phase_inc);
+				PHASE_INC = yc_modes[i].phase_inc;
+				break;
+			}
+		}
+
 		spi_uio_cmd_cont(UIO_SET_YC_PAR);
 		spi_w((pal ? 4 : 0) | ((cfg.vga_mode_int == 3) ? 3 : 1));
 		spi_w(PHASE_INC);
@@ -2743,8 +2763,6 @@ static void set_yc_mode()
 		spi_w(COLORBURST_RANGE);
 		spi_w(COLORBURST_RANGE >> 16);
 		DisableIO();
-
-		printf("Send YC parameters: %s PHASE_INC=%lld, COLORBURST_START=%d, COLORBURST_END=%d\n", pal ? "PAL" : "NTSC", PHASE_INC, COLORBURST_START, COLORBURST_END);
 	}
 	else
 	{
diff --git a/yc.txt b/yc.txt
new file mode 100644
index 0000000..4a964e7
--- /dev/null
+++ b/yc.txt
@@ -0,0 +1,14 @@
+;
+; PHASE_INC override per <core_fps> mode.
+; It affects only CVBS video output.
+; S-Video doesn't need this file.
+;
+
+SNES_60.1=91625968981
+SNES_60.0i=91625968981
+SNES_50.0=114532461227
+SNES_49.9i=114532461227
+NEOGEO_59.2=81994830080
+NEOGEO_59.6=81425421603
+NEOGEO_50.1=101558653516
+NEOGEO_50.4=100853152548