igfx: get edid information from lvds

1 files changed, 414 insertions, 0 deletions

diff --git a/sys/src/cmd/aux/vga/edid.c b/sys/src/cmd/aux/vga/edid.c
new file mode 100644
index 000000000..ba95d2611
--- /dev/null
+++ b/sys/src/cmd/aux/vga/edid.c
@@ -0,0 +1,414 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <ndb.h>
+
+#include "pci.h"
+#include "vga.h"
+#include "edid.h"
+
+static Modelist*
+addmode(Modelist *l, Mode m)
+{
+	int rr;
+	Modelist **lp;
+
+	rr = (m.frequency+m.ht*m.vt/2)/(m.ht*m.vt);
+	snprint(m.name, sizeof m.name, "%dx%d@%dHz", m.x, m.y, rr);
+
+	for(lp=&l; *lp; lp=&(*lp)->next){
+		if(strcmp((*lp)->name, m.name) == 0){
+			(*lp)->Mode = m;
+			return l;
+		}
+	}
+
+	*lp = alloc(sizeof(**lp));
+	(*lp)->Mode = m;
+	return l;
+}
+
+/*
+ * Parse VESA EDID information.  Based on the VESA
+ * Extended Display Identification Data standard, Version 3,
+ * November 13, 1997.  See /public/doc/vesa/edidv3.pdf.
+ *
+ * This only handles 128-byte EDID blocks.  Until I find
+ * a monitor that produces 256-byte blocks, I'm not going
+ * to try to decode them.
+ */
+
+/*
+ * Established timings block.  There is a bitmap
+ * that says whether each mode is supported.  Most
+ * of these have VESA definitions.  Those that don't are marked
+ * as such, and we ignore them (the lookup fails).
+ */
+static char *estabtime[] = {
+	"720x400@70Hz",	/* non-VESA: IBM, VGA */
+	"720x400@88Hz",	/* non-VESA: IBM, XGA2 */
+	"640x480@60Hz",
+	"640x480@67Hz",	/* non-VESA: Apple, Mac II */
+	"640x480@72Hz",
+	"640x480@75Hz",
+	"800x600@56Hz",
+	"800x600@60Hz",
+
+	"800x600@72Hz",
+	"800x600@75Hz",
+	"832x624@75Hz",	/* non-VESA: Apple, Mac II */
+	"1024x768i@87Hz",	/* non-VESA: IBM */
+	"1024x768@60Hz",
+	"1024x768@70Hz",
+	"1024x768@75Hz",
+	"1280x1024@75Hz",
+
+	"1152x870@75Hz",	/* non-VESA: Apple, Mac II */
+};
+
+/*
+ * Decode the EDID detailed timing block.  See pp. 20-21 of the standard.
+ */
+static int
+decodedtb(Mode *m, uchar *p)
+{
+	int ha, hb, hso, hspw, rr, va, vb, vso, vspw;
+	/* int hbord, vbord, dxmm, dymm, hbord, vbord; */
+
+	memset(m, 0, sizeof *m);
+
+	m->frequency = ((p[1]<<8) | p[0]) * 10000;
+
+	ha = ((p[4] & 0xF0)<<4) | p[2];		/* horizontal active */
+	hb = ((p[4] & 0x0F)<<8) | p[3];		/* horizontal blanking */
+	va = ((p[7] & 0xF0)<<4) | p[5];		/* vertical active */
+	vb = ((p[7] & 0x0F)<<8) | p[6];		/* vertical blanking */
+	hso = ((p[11] & 0xC0)<<2) | p[8];	/* horizontal sync offset */
+	hspw = ((p[11] & 0x30)<<4) | p[9];	/* horizontal sync pulse width */
+	vso = ((p[11] & 0x0C)<<2) | ((p[10] & 0xF0)>>4);	/* vertical sync offset */
+	vspw = ((p[11] & 0x03)<<4) | (p[10] & 0x0F);		/* vertical sync pulse width */
+
+	/* dxmm = (p[14] & 0xF0)<<4) | p[12]; 	/* horizontal image size (mm) */
+	/* dymm = (p[14] & 0x0F)<<8) | p[13];	/* vertical image size (mm) */
+	/* hbord = p[15];		/* horizontal border (pixels) */
+	/* vbord = p[16];		/* vertical border (pixels) */
+
+	m->x = ha;
+	m->y = va;
+
+	m->ht = ha+hb;
+	m->shb = ha+hso;
+	m->ehb = ha+hso+hspw;
+
+	m->vt = va+vb;
+	m->vrs = va+vso;
+	m->vre = va+vso+vspw;
+
+	if(p[17] & 0x80)	/* interlaced */
+		m->interlace = 'v';
+
+	if(p[17] & 0x60)	/* some form of stereo monitor mode; no support */
+		return -1;
+
+	/*
+	 * Sync signal description.  I have no idea how to properly handle the 
+	 * first three cases, which I think are aimed at things other than
+	 * canonical SVGA monitors.
+	 */
+	switch((p[17] & 0x18)>>3) {
+	case 0:	/* analog composite sync signal*/
+	case 1:	/* bipolar analog composite sync signal */
+		/* p[17] & 0x04 means serration: hsync during vsync */
+		/* p[17] & 0x02 means sync pulse appears on RGB not just G */
+		break;
+
+	case 2:	/* digital composite sync signal */
+		/* p[17] & 0x04 means serration: hsync during vsync */
+		/* p[17] & 0x02 means hsync positive outside vsync */
+		break;
+
+	case 3:	/* digital separate sync signal; the norm */
+		m->vsync = (p[17] & 0x04) ? '+' : '-';
+		m->hsync = (p[17] & 0x02) ? '+' : '-';
+		break;
+	}
+	/* p[17] & 0x01 is another stereo bit, only referenced if p[17] & 0x60 != 0 */
+
+	rr = (m->frequency+m->ht*m->vt/2) / (m->ht*m->vt);
+
+	snprint(m->name, sizeof m->name, "%dx%d@%dHz", m->x, m->y, rr);
+
+	return 0;
+}
+
+static int
+vesalookup(Mode *m, char *name)
+{
+	Mode **p;
+
+	for(p=vesamodes; *p; p++)
+		if(strcmp((*p)->name, name) == 0) {
+			*m = **p;
+			return 0;
+		}
+	return -1;
+}
+
+static int
+decodesti(Mode *m, uchar *p)
+{
+	int x, y, rr;
+	char str[20];
+
+	x = (p[0]+31)*8;
+	switch((p[1]>>6) & 3){
+	default:
+	case 0:
+		y = x;
+		break;
+	case 1:
+		y = (x*4)/3;
+		break;
+	case 2:
+		y = (x*5)/4;
+		break;
+	case 3:
+		y = (x*16)/9;
+		break;
+	}
+	rr = (p[1] & 0x1F) + 60;
+
+	sprint(str, "%dx%d@%dHz", x, y, rr);
+	return vesalookup(m, str);
+}
+
+int
+parseedid128(Edid *e, void *v)
+{
+	static uchar magic[8] = { 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00 };
+	uchar *p, *q, sum;
+	int dpms, estab, i, m, vid;
+	Mode mode;
+
+	memset(e, 0, sizeof *e);
+
+	p = (uchar*)v;
+	if(memcmp(p, magic, 8) != 0) {
+		werrstr("bad edid header");
+		return -1;
+	}
+
+	sum = 0;
+	for(i=0; i<128; i++) 
+		sum += p[i];
+	if(sum != 0) {
+		werrstr("bad edid checksum");
+		return -1;
+	}
+	p += 8;
+
+	assert(p == (uchar*)v+8);	/* assertion offsets from pp. 12-13 of the standard */
+	/*
+	 * Manufacturer name is three 5-bit ascii letters, packed
+	 * into a big endian [sic] short in big endian order.  The high bit is unused.
+	 */
+	i = (p[0]<<8) | p[1];
+	p += 2;
+	e->mfr[0] = 'A'-1 + ((i>>10) & 0x1F);
+	e->mfr[1] = 'A'-1 + ((i>>5) & 0x1F);
+	e->mfr[2] = 'A'-1 + (i & 0x1F);
+	e->mfr[3] = '\0';
+
+	/*
+	 * Product code is a little endian short.
+	 */
+	e->product = (p[1]<<8) | p[0];
+	p += 2;
+
+	/*
+	 * Serial number is a little endian long, 0x01010101 = unused.
+	 */
+	e->serial = (p[3]<<24) | (p[2]<<16) | (p[1]<<8) | p[0];
+	p += 4;
+	if(e->serial == 0x01010101)
+		e->serial = 0;
+
+	e->mfrweek = *p++;
+	e->mfryear = 1990 + *p++;
+
+	assert(p == (uchar*)v+8+10);
+	/*
+	 * Structure version is next two bytes: major.minor.
+	 */
+	e->version = *p++;
+	e->revision = *p++;
+
+	assert(p == (uchar*)v+8+10+2);
+	/*
+	 * Basic display parameters / features.
+	 */
+	/*
+	 * Video input definition byte: 0x80 tells whether it is
+	 * an analog or digital screen; we ignore the other bits.
+	 * See p. 15 of the standard.
+	 */
+	vid = *p++;
+	if(vid & 0x80)
+		e->flags |= Fdigital;
+
+	e->dxcm = *p++;
+	e->dycm = *p++;
+	e->gamma = 100 + *p++;
+	dpms = *p++;
+	if(dpms & 0x80)
+		e->flags |= Fdpmsstandby;
+	if(dpms & 0x40)
+		e->flags |= Fdpmssuspend;
+	if(dpms & 0x20)
+		e->flags |= Fdpmsactiveoff;
+	if((dpms & 0x18) == 0x00)
+		e->flags |= Fmonochrome;
+	if(dpms & 0x01)
+		e->flags |= Fgtf;
+
+	assert(p == (uchar*)v+8+10+2+5);
+	/*
+	 * Color characteristics currently ignored.
+	 */
+	p += 10;
+
+	assert(p == (uchar*)v+8+10+2+5+10);
+	/*
+	 * Established timings: a bitmask of 19 preset timings.
+	 */
+	estab = (p[0]<<16) | (p[1]<<8) | p[2];
+	p += 3;
+
+	for(i=0, m=1<<23; i<nelem(estabtime); i++, m>>=1)
+		if(estab & m)
+			if(vesalookup(&mode, estabtime[i]) == 0)
+				e->modelist = addmode(e->modelist,  mode);
+
+	assert(p == (uchar*)v+8+10+2+5+10+3);
+	/*
+	 * Standard Timing Identifications: eight 2-byte selectors
+	 * of more standard timings.
+	 */
+	for(i=0; i<8; i++, p+=2)
+		if(decodesti(&mode, p+2*i) == 0)
+			e->modelist = addmode(e->modelist, mode);
+
+	assert(p == (uchar*)v+8+10+2+5+10+3+16);
+	/*
+	 * Detailed Timings
+	 */
+	for(i=0; i<4; i++, p+=18) {
+		if(p[0] || p[1]) {	/* detailed timing block: p[0] or p[1] != 0 */
+			if(decodedtb(&mode, p) == 0)
+				e->modelist = addmode(e->modelist, mode);
+		} else if(p[2]==0) {	/* monitor descriptor block */
+			switch(p[3]) {
+			case 0xFF:	/* monitor serial number (13-byte ascii, 0A terminated) */
+				if(q = memchr(p+5, 0x0A, 13))
+					*q = '\0';
+				memset(e->serialstr, 0, sizeof(e->serialstr));
+				strncpy(e->serialstr, (char*)p+5, 13);
+				break;
+			case 0xFE:	/* ascii string (13-byte ascii, 0A terminated) */
+				break;
+			case 0xFD:	/* monitor range limits */
+				e->rrmin = p[5];
+				e->rrmax = p[6];
+				e->hrmin = p[7]*1000;
+				e->hrmax = p[8]*1000;
+				if(p[9] != 0xFF)
+					e->pclkmax = p[9]*10*1000000;
+				break;
+			case 0xFC:	/* monitor name (13-byte ascii, 0A terminated) */
+				if(q = memchr(p+5, 0x0A, 13))
+					*q = '\0';
+				memset(e->name, 0, sizeof(e->name));
+				strncpy(e->name, (char*)p+5, 13);
+				break;
+			case 0xFB:	/* extra color point data */
+				break;
+			case 0xFA:	/* extra standard timing identifications */
+				for(i=0; i<6; i++)
+					if(decodesti(&mode, p+5+2*i) == 0)
+						e->modelist = addmode(e->modelist, mode);
+				break;
+			}
+		}
+	}
+
+	assert(p == (uchar*)v+8+10+2+5+10+3+16+72);
+	return 0;
+}
+
+Flag edidflags[] = {
+	Fdigital, "digital",
+	Fdpmsstandby, "standby",
+	Fdpmssuspend, "suspend",
+	Fdpmsactiveoff, "activeoff",
+	Fmonochrome, "monochrome",
+	Fgtf, "gtf",
+	0
+};
+
+void
+printflags(Flag *f, int b)
+{
+	int i;
+
+	for(i=0; f[i].bit; i++)
+		if(f[i].bit & b)
+			Bprint(&stdout, " %s", f[i].desc);
+	Bprint(&stdout, "\n");
+}
+
+void
+printedid(Edid *e)
+{
+	Modelist *l;
+
+	printitem("edid", "mfr");
+	Bprint(&stdout, "%s\n", e->mfr);
+	printitem("edid", "serialstr");
+	Bprint(&stdout, "%s\n", e->serialstr);
+	printitem("edid", "name");
+	Bprint(&stdout, "%s\n", e->name);
+	printitem("edid", "product");
+	Bprint(&stdout, "%d\n", e->product);
+	printitem("edid", "serial");
+	Bprint(&stdout, "%lud\n", e->serial);
+	printitem("edid", "version");
+	Bprint(&stdout, "%d.%d\n", e->version, e->revision);
+	printitem("edid", "mfrdate");
+	Bprint(&stdout, "%d.%d\n", e->mfryear, e->mfrweek);
+	printitem("edid", "size (cm)");
+	Bprint(&stdout, "%dx%d\n", e->dxcm, e->dycm);
+	printitem("edid", "gamma");
+	Bprint(&stdout, "%.2f\n", e->gamma/100.);
+	printitem("edid", "vert (Hz)");
+	Bprint(&stdout, "%d-%d\n", e->rrmin, e->rrmax);
+	printitem("edid", "horz (Hz)");
+	Bprint(&stdout, "%d-%d\n", e->hrmin, e->hrmax);
+	printitem("edid", "pclkmax");
+	Bprint(&stdout, "%lud\n", e->pclkmax);
+	printitem("edid", "flags");
+	printflags(edidflags, e->flags);
+
+	for(l=e->modelist; l; l=l->next){
+		printitem("edid", l->name);
+		Bprint(&stdout, "\n\t\tclock=%g\n"
+			"\t\tshb=%d ehb=%d ht=%d\n"
+			"\t\tvrs=%d vre=%d vt=%d\n"
+			"\t\thsync=%c vsync=%c %s\n",
+			l->frequency/1.e6, 
+			l->shb, l->ehb, l->ht,
+			l->vrs, l->vre, l->vt,
+			l->hsync?l->hsync:'?',
+			l->vsync?l->vsync:'?',
+			l->interlace?"interlace=v" : "");
+	}
+}