artist: Fix X cursor position calculation in X11

The X cursor postion can be calculated based on the backporch and
interleave values.  In the emulation we ignore the HP-UX settings for
backporch and use instead twice the size of the emulated cursor.  With
those changes the X-position of the graphics cursor is now finally
working correctly on HP-UX 10 and HP-UX 11.

Based on coding in Xorg X11R6.6

Signed-off-by: Helge Deller <deller@gmx.de>
This commit is contained in:
Helge Deller 2022-05-12 13:40:39 +02:00
parent caca6e618d
commit 9ef2c6b4ab

View file

@ -1,7 +1,8 @@
/*
* QEMU HP Artist Emulation
*
* Copyright (c) 2019 Sven Schnelle <svens@stackframe.org>
* Copyright (c) 2019-2022 Sven Schnelle <svens@stackframe.org>
* Copyright (c) 2022 Helge Deller <deller@gmx.de>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
*/
@ -313,19 +314,15 @@ static void artist_rop8(ARTISTState *s, struct vram_buffer *buf,
static void artist_get_cursor_pos(ARTISTState *s, int *x, int *y)
{
/*
* Don't know whether these magic offset values are configurable via
* some register. They seem to be the same for all resolutions.
* The cursor values provided in the registers are:
* X-value: -295 (for HP-UX 11) and 338 (for HP-UX 10.20) up to 2265
* Y-value: 1146 down to 0
* The emulated Artist graphic is like a CRX graphic, and as such
* it's usually fixed at 1280x1024 pixels.
* Because of the maximum Y-value of 1146 you can not choose a higher
* vertical resolution on HP-UX (unless you disable the mouse).
* Other resolutions may work, but no guarantee.
*/
static int offset = 338;
int lx;
unsigned int hbp_times_vi, horizBackPorch;
int16_t xHi, xLo;
const int videoInterleave = 4;
const int pipelineDelay = 4;
/* ignore if uninitialized */
if (s->cursor_pos == 0) {
@ -333,16 +330,23 @@ static void artist_get_cursor_pos(ARTISTState *s, int *x, int *y)
return;
}
lx = artist_get_x(s->cursor_pos);
if (lx < offset) {
offset = lx;
}
*x = (lx - offset) / 2;
/*
* Calculate X position based on backporch and interleave values.
* Based on code from Xorg X11R6.6
*/
horizBackPorch = ((s->horiz_backporch & 0xff0000) >> 16) +
((s->horiz_backporch & 0xff00) >> 8) + 2;
hbp_times_vi = horizBackPorch * videoInterleave;
xHi = s->cursor_pos >> 19;
*x = ((xHi + pipelineDelay) * videoInterleave) - hbp_times_vi;
xLo = (s->cursor_pos >> 16) & 0x07;
*x += ((xLo - hbp_times_vi) & (videoInterleave - 1)) + 8 - 1;
/* subtract cursor offset from cursor control register */
*x -= (s->cursor_cntrl & 0xf0) >> 4;
/* height minus nOffscreenScanlines is stored in cursor control register */
/* Calculate Y position */
*y = s->height - artist_get_y(s->cursor_pos);
*y -= (s->cursor_cntrl & 0x0f);
@ -1056,6 +1060,8 @@ static void artist_reg_write(void *opaque, hwaddr addr, uint64_t val,
break;
case HORIZ_BACKPORCH:
/* overwrite HP-UX settings to fix X cursor position. */
val = (NGLE_MAX_SPRITE_SIZE << 16) + (NGLE_MAX_SPRITE_SIZE << 8);
combine_write_reg(addr, val, size, &s->horiz_backporch);
break;