[PATCH v2 4/7] artist: Fix vertical X11 cursor position in HP-UX

[Helge Deller <deller@gmx.de>]

Drop the hard-coded value of 1146 lines which seems to work with HP-UX
11, but not with HP-UX 10. Instead encode the screen height in byte 0 of
active_lines_low and byte 3 of misc_video as it's expected by the Xorg
X11 graphics driver.

This potentially allows for higher vertical screen resolutions than
1280x1024 with X11.

Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
 hw/display/artist.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/hw/display/artist.c b/hw/display/artist.c
index c8b261a52e..780cb15026 100644
--- a/hw/display/artist.c
+++ b/hw/display/artist.c
@@ -337,10 +337,11 @@ static void artist_get_cursor_pos(ARTISTState *s, int *x, int *y)
     }
     *x = (lx - offset) / 2;

-    *y = 1146 - artist_get_y(s->cursor_pos);
-
     /* subtract cursor offset from cursor control register */
     *x -= (s->cursor_cntrl & 0xf0) >> 4;
+
+    /* height minus nOffscreenScanlines is stored in cursor control register */
+    *y = s->height - artist_get_y(s->cursor_pos);
     *y -= (s->cursor_cntrl & 0x0f);

     if (*x > s->width) {
@@ -1158,14 +1159,17 @@ static uint64_t artist_reg_read(void *opaque, hwaddr addr, unsigned size)
     case ACTIVE_LINES_LOW:
         val = s->active_lines_low;
         /* activeLinesLo for cursor is in reg20.b.b0 */
-        val |= ((s->height - 1) & 0xff);
+        val &= ~(0xff << 24);
+        val |= (s->height & 0xff) << 24;
         break;

     case MISC_VIDEO:
         /* emulate V-blank */
-        val = s->misc_video ^ 0x00040000;
+        s->misc_video ^= 0x00040000;
         /* activeLinesHi for cursor is in reg21.b.b2 */
-        val |= ((s->height - 1) & 0xff00);
+        val = s->misc_video;
+        val &= ~0xff00UL;
+        val |= (s->height & 0xff00);
         break;

     case MISC_CTRL:
--
2.35.3