svn commit: r293614 - head/sys/dev/vt/hw/ofwfb

[Nathan Whitehorn]

Author: nwhitehorn
Date: Sat Jan  9 21:28:56 2016
New Revision: 293614
URL: https://svnweb.freebsd.org/changeset/base/293614

Log:
  Make graphical consoles work under PowerKVM. Without using hypercalls, it is
  not possible to write the framebuffer before pmap is up. Solve this by
  deferring initialization until that happens, like on PS3.
  
  MFC after:	1 week

Modified:
  head/sys/dev/vt/hw/ofwfb/ofwfb.c

Modified: head/sys/dev/vt/hw/ofwfb/ofwfb.c
==============================================================================
--- head/sys/dev/vt/hw/ofwfb/ofwfb.c	Sat Jan  9 20:18:53 2016	(r293613)
+++ head/sys/dev/vt/hw/ofwfb/ofwfb.c	Sat Jan  9 21:28:56 2016	(r293614)
@@ -57,6 +57,7 @@ struct ofwfb_softc {
 	int		iso_palette;
 };
 
+static void ofwfb_initialize(struct vt_device *vd);
 static vd_probe_t	ofwfb_probe;
 static vd_init_t	ofwfb_init;
 static vd_bitblt_text_t	ofwfb_bitblt_text;
@@ -124,6 +125,18 @@ ofwfb_bitblt_bitmap(struct vt_device *vd
 		uint8_t	 c[4];
 	} ch1, ch2;
 
+#ifdef __powerpc__
+	/* Deal with unmapped framebuffers */
+	if (sc->fb_flags & FB_FLAG_NOWRITE) {
+		if (pmap_bootstrapped) {
+			sc->fb_flags &= ~FB_FLAG_NOWRITE;
+			ofwfb_initialize(vd);
+		} else {
+			return;
+		}
+	}
+#endif
+
 	fgc = sc->fb_cmap[fg];
 	bgc = sc->fb_cmap[bg];
 	b = m = 0;
@@ -271,6 +284,11 @@ ofwfb_initialize(struct vt_device *vd)
 	cell_t retval;
 	uint32_t oldpix;
 
+	sc->fb.fb_cmsize = 16;
+
+	if (sc->fb.fb_flags & FB_FLAG_NOWRITE)
+		return;
+
 	/*
 	 * Set up the color map
 	 */
@@ -318,8 +336,6 @@ ofwfb_initialize(struct vt_device *vd)
 		panic("Unknown color space depth %d", sc->fb.fb_bpp);
 		break;
         }
-
-	sc->fb.fb_cmsize = 16;
 }
 
 static int
@@ -466,6 +482,11 @@ ofwfb_init(struct vt_device *vd)
 	#if defined(__powerpc__)
 		OF_decode_addr(node, fb_phys, &sc->sc_memt, &sc->fb.fb_vbase);
 		sc->fb.fb_pbase = sc->fb.fb_vbase; /* 1:1 mapped */
+		#ifdef __powerpc64__
+		/* Real mode under a hypervisor probably doesn't cover FB */
+		if (!(mfmsr() & (PSL_HV | PSL_DR)))
+			sc->fb.fb_flags |= FB_FLAG_NOWRITE;
+		#endif
 	#else
 		/* No ability to interpret assigned-addresses otherwise */
 		return (CN_DEAD);