From: David Eger It's a simple issue of taking care of overlapping regions in calls to copyarea(). --- 25-akpm/drivers/video/aty/radeon_accel.c | 21 +++++++++++++++++---- 1 files changed, 17 insertions(+), 4 deletions(-) diff -puN drivers/video/aty/radeon_accel.c~radeon-fb-screen-corruption-fix drivers/video/aty/radeon_accel.c --- 25/drivers/video/aty/radeon_accel.c~radeon-fb-screen-corruption-fix Mon Apr 19 15:26:36 2004 +++ 25-akpm/drivers/video/aty/radeon_accel.c Mon Apr 19 15:26:36 2004 @@ -53,6 +53,18 @@ void radeonfb_fillrect(struct fb_info *i static void radeonfb_prim_copyarea(struct radeonfb_info *rinfo, const struct fb_copyarea *area) { + int xdir, ydir; + u32 sx, sy, dx, dy, w, h; + + w = area->width; h = area->height; + dx = area->dx; dy = area->dy; + sx = area->sx; sy = area->sy; + xdir = sx - dx; + ydir = sy - dy; + + if ( xdir < 0 ) { sx += w-1; dx += w-1; } + if ( ydir < 0 ) { sy += h-1; dy += h-1; } + radeon_fifo_wait(3); OUTREG(DP_GUI_MASTER_CNTL, rinfo->dp_gui_master_cntl /* i.e. GMC_DST_32BPP */ @@ -60,12 +72,13 @@ static void radeonfb_prim_copyarea(struc | ROP3_S | DP_SRC_RECT ); OUTREG(DP_WRITE_MSK, 0xffffffff); - OUTREG(DP_CNTL, (DST_X_LEFT_TO_RIGHT | DST_Y_TOP_TO_BOTTOM)); + OUTREG(DP_CNTL, (xdir>=0 ? DST_X_LEFT_TO_RIGHT : 0) + | (ydir>=0 ? DST_Y_TOP_TO_BOTTOM : 0)); radeon_fifo_wait(3); - OUTREG(SRC_Y_X, (area->sy << 16) | area->sx); - OUTREG(DST_Y_X, (area->dy << 16) | area->dx); - OUTREG(DST_HEIGHT_WIDTH, (area->height << 16) | area->width); + OUTREG(SRC_Y_X, (sy << 16) | sx); + OUTREG(DST_Y_X, (dy << 16) | dx); + OUTREG(DST_HEIGHT_WIDTH, (h << 16) | w); } _