Fix VT mode change vs. fbcon
Subsystems (5)
PATCH 1/1 Fix VT mode change vs. fbcon
Hi Linus !
This patch implements what we discussed earlier to fix the switch bewteen KD_GRAPHICS and KD_TEXT.
It has been tested for a few days now and appear to resolve the problem for affected users.
James: I know you have some objections, I don't fully agree with them, and I want that in asap now, that bug has been plaguing fbdev since the very beginning and it's time to get rid of that and my corresponding todolist entry. You are welcome to propose a patch on top of this one if you feel you can make things cleaner. The approach of adding a parameter to con_blank() is Linus idea btw :)
I didn't add a separate function as that would have made the butchering of drivers/char/vt beyond what I want to deal with in 2.6.
Ben.
===== drivers/char/vt.c 1.61 vs edited =====
drivers/char/vt.c +21 -10
@@ -2743,12 +2743,12 @@* Called only if powerdown features are allowed. */ switch (vesa_blank_mode) { -case VESA_NO_BLANKING : - c->vc_sw->con_blank (c,VESA_VSYNC_SUSPEND +1 ); +case VESA_NO_BLANKING : + c->vc_sw->con_blank (c,VESA_VSYNC_SUSPEND +1 ,0 );break ; -case VESA_VSYNC_SUSPEND : -case VESA_HSYNC_SUSPEND : - c->vc_sw->con_blank (c,VESA_POWERDOWN +1 ); +case VESA_VSYNC_SUSPEND : +case VESA_HSYNC_SUSPEND : + c->vc_sw->con_blank (c,VESA_POWERDOWN +1 ,0 );break ; } }
@@ -2776,7 +2776,7 @@if (entering_gfx) {hide_cursor (currcons);save_screen (currcons); - sw->con_blank (vc_cons[currcons].d,-1 ); + sw->con_blank (vc_cons[currcons].d,-1 ,1 ); console_blanked = fg_console +1 ;set_origin (currcons);return ;
@@ -2794,7 +2794,7 @@save_screen (currcons);/* In case we need to reset origin, blanking hook returns 1 */ - i = sw->con_blank (vc_cons[currcons].d,1 ); + i = sw->con_blank (vc_cons[currcons].d,1 ,0 ); console_blanked = fg_console +1 ;if (i)set_origin (currcons);
@@ -2808,14 +2808,14 @@ }if (vesa_blank_mode) - sw->con_blank (vc_cons[currcons].d, vesa_blank_mode +1 ); + sw->con_blank (vc_cons[currcons].d, vesa_blank_mode +1 ,0 ); }/* * Called by timer as well as from vt_console_driver */ -void unblank_screen (void ) +void do_unblank_screen (int leaving_gfx) {int currcons;
@@ -2839,13 +2839,24 @@ } console_blanked =0 ; -if (sw->con_blank (vc_cons[currcons].d,0 )) +if (sw->con_blank (vc_cons[currcons].d,0 , leaving_gfx))/* Low-level driver cannot restore -> do it ourselves */ update_screen (fg_console);if (console_blank_hook)console_blank_hook (0 );set_palette (currcons);set_cursor (fg_console); +} + +/* +* This is called by the outside world to cause a forced unblank, mostly for +* oopses. Currently, I just call do_unblank_screen(0), but we could eventually +* call it with 1 as an argument and so force a mode restore... that may kill +* X or at least garbage the screen but would also make the Oops visible... +*/ +void unblank_screen (void ) +{ +do_unblank_screen (0 ); }/*
===== drivers/char/vt_ioctl.c 1.34 vs edited =====
drivers/char/vt_ioctl.c +3 -3
@@ -497,7 +497,7 @@*/ acquire_console_sem ();if (arg ==KD_TEXT ) -unblank_screen (); +do_unblank_screen (1 );else do_blank_screen (1 );release_console_sem ();
@@ -1103,7 +1103,7 @@if (old_vc_mode != vt_cons[new_console]->vc_mode) {if (vt_cons[new_console]->vc_mode ==KD_TEXT ) -unblank_screen (); +do_unblank_screen (1 );else do_blank_screen (1 ); }
@@ -1138,7 +1138,7 @@if (old_vc_mode != vt_cons[new_console]->vc_mode) {if (vt_cons[new_console]->vc_mode ==KD_TEXT ) -unblank_screen (); +do_unblank_screen (1 );else do_blank_screen (1 ); }
===== drivers/video/fbmem.c 1.90 vs edited =====
drivers/video/fbmem.c +2 -1
@@ -943,7 +943,8 @@ {int err; -if (memcmp (&info->var, var,sizeof (struct fb_var_screeninfo ))) { +if ((var->activate &FB_ACTIVATE_FORCE ) || +memcmp (&info->var, var,sizeof (struct fb_var_screeninfo ))) {if (!info->fbops->fb_check_var) { *var = info->var;return 0 ;
===== drivers/video/console/fbcon.c 1.109 vs edited =====
drivers/video/console/fbcon.c +13 -4
@@ -159,7 +159,7 @@static void fbcon_bmove (struct vc_data *vc,int sy,int sx,int dy,int dx,int height,int width);static int fbcon_switch (struct vc_data *vc); -static int fbcon_blank (struct vc_data *vc,int blank); +static int fbcon_blank (struct vc_data *vc,int blank,int mode_switch);static int fbcon_font_op (struct vc_data *vc,struct console_font_op *op);static int fbcon_set_palette (struct vc_data *vc,unsigned char *table);static int fbcon_scrolldelta (struct vc_data *vc,int lines);
@@ -1696,14 +1696,23 @@return 1 ; } -static int fbcon_blank (struct vc_data *vc,int blank) +static int fbcon_blank (struct vc_data *vc,int blank,int mode_switch) {unsigned short charmask = vc->vc_hi_font_mask ?0x1ff :0xff ;struct fb_info *info = registered_fb[(int ) con2fb_map[vc->vc_num]];struct display *p = &fb_display[vc->vc_num]; -if (blank <0 )/* Entering graphics mode */ -return 0 ; +if (mode_switch) { +struct fb_info *info = registered_fb[(int ) con2fb_map[vc->vc_num]]; +struct fb_var_screeninfo var = info->var; + +if (blank) { +fbcon_cursor (vc,CM_ERASE ); +return 0 ; + } + var.activate =FB_ACTIVATE_NOW |FB_ACTIVATE_FORCE ; +fb_set_var (info, &var); + }fbcon_cursor (vc, blank ?CM_ERASE :CM_DRAW );
===== drivers/video/console/promcon.c 1.9 vs edited =====
drivers/video/console/promcon.c +1 -1
@@ -463,7 +463,7 @@ }static int -promcon_blank (struct vc_data *conp,int blank) +promcon_blank (struct vc_data *conp,int blank,int mode_switch) {if (blank) {promcon_puts ("\033[H\033[J\033[7m \033[m\b" ,15 );
===== drivers/video/console/sticon.c 1.8 vs edited =====
drivers/video/console/sticon.c +9 -17
@@ -250,26 +250,18 @@return 0 ; } -static int sticon_blank (struct vc_data *c,int blank) +static int sticon_blank (struct vc_data *c,int blank,int mode_switch) { -switch (blank) { -case 0 :/* unblank */ - vga_is_gfx =0 ; -/* Tell console.c that it has to restore the screen itself */ -return 1 ; -case 1 :/* normal blanking */ -default :/* VESA blanking */ -if (vga_is_gfx) -return 0 ; -sticon_set_origin (c); -sti_clear (sticon_sti,0 ,0 , c->vc_rows, c->vc_cols,BLANK ); -return 1 ; -case -1 :/* Entering graphic mode */ -sti_clear (sticon_sti,0 ,0 , c->vc_rows, c->vc_cols,BLANK ); - vga_is_gfx =1 ; +if (blank ==0 ) { +if (mode_switch) + vga_is_gfx =0 ;return 1 ; } -return 1 ;/* console needs to restore screen itself */ +sticon_set_origin (c); +sti_clear (sticon_sti,0 ,0 , c->vc_rows, c->vc_cols,BLANK ); +if (mode_switch) + vga_is_gfx =1 ; +return 1 ; }static int sticon_scrolldelta (struct vc_data *conp,int lines)
===== drivers/video/console/vgacon.c 1.15 vs edited =====
drivers/video/console/vgacon.c +6 -8
@@ -76,7 +76,7 @@static void vgacon_deinit (struct vc_data *c);static void vgacon_cursor (struct vc_data *c,int mode);static int vgacon_switch (struct vc_data *c); -static int vgacon_blank (struct vc_data *c,int blank); +static int vgacon_blank (struct vc_data *c,int blank,int mode_switch);static int vgacon_font_op (struct vc_data *c,struct console_font_op *op);static int vgacon_set_palette (struct vc_data *vc,unsigned char *table);static int vgacon_scrolldelta (struct vc_data *c,int lines);
@@ -661,7 +661,7 @@ } } -static int vgacon_blank (struct vc_data *c,int blank) +static int vgacon_blank (struct vc_data *c,int blank,int mode_switch) {switch (blank) {case 0 :/* Unblank */
@@ -678,7 +678,8 @@/* Tell console.c that it has to restore the screen itself */ return 1 ;case 1 :/* Normal blanking */ -if (vga_video_type ==VIDEO_TYPE_VGAC ) { +case -1 :/* Obsolete */ +if (!mode_switch && vga_video_type ==VIDEO_TYPE_VGAC ) {vga_pal_blank (&state); vga_palette_blanked =1 ;return 0 ;
@@ -686,11 +687,8 @@vgacon_set_origin (c);scr_memsetw ((void *) vga_vram_base,BLANK , c->vc_screenbuf_size); -return 1 ; -case -1 :/* Entering graphic mode */ -scr_memsetw ((void *) vga_vram_base,BLANK , - c->vc_screenbuf_size); - vga_is_gfx =1 ; +if (mode_switch) + vga_is_gfx =1 ;return 1 ;default :/* VESA blanking */ if (vga_video_type ==VIDEO_TYPE_VGAC ) {
===== include/linux/console.h 1.11 vs edited =====
include/linux/console.h +1 -1
@@ -37,7 +37,7 @@int (*con_scroll)(struct vc_data *,int ,int ,int ,int );void (*con_bmove)(struct vc_data *,int ,int ,int ,int ,int ,int );int (*con_switch)(struct vc_data *); -int (*con_blank)(struct vc_data *,int ); +int (*con_blank)(struct vc_data *,int ,int );int (*con_font_op)(struct vc_data *,struct console_font_op *);int (*con_resize)(struct vc_data *,unsigned int ,unsigned int );int (*con_set_palette)(struct vc_data *,unsigned char *);
===== include/linux/fb.h 1.60 vs edited =====
include/linux/fb.h +1 -0
@@ -152,6 +152,7 @@#define FB_ACTIVATE_VBL 16/* activate values on next vbl */ #define FB_CHANGE_CMAP_VBL 32/* change colormap on vbl */ #define FB_ACTIVATE_ALL 64/* change all VCs on this fb */ +#define FB_ACTIVATE_FORCE 128/* force apply even when no change*/ #define FB_ACCELF_TEXT 1/* text mode acceleration */
===== include/linux/vt_kern.h 1.9 vs edited =====
include/linux/vt_kern.h +2 -1
@@ -44,7 +44,8 @@void vc_disallocate (unsigned int console);void reset_palette (int currcons);void set_palette (int currcons); -void do_blank_screen (int gfx_mode); +void do_blank_screen (int entering_gfx); +void do_unblank_screen (int leaving_gfx);void unblank_screen (void );void poke_blanked_console (void );int con_font_op (int currcons,struct console_font_op *op);
Quoted 22 lines
drivers/char/vt_ioctl.c +2
-2@@ -497,7 +497,7 @@*/ acquire_console_sem ();if (arg ==KD_TEXT ) -unblank_screen (); +do_unblank_screen (1 );else do_blank_screen (1 );release_console_sem ();@@ -1103,7 +1103,7 @@if (old_vc_mode != vt_cons[new_console]->vc_mode) {if (vt_cons[new_console]->vc_mode ==KD_TEXT ) -unblank_screen (); +do_unblank_screen (1 );else do_blank_screen (1 ); }
drivers/char/vt_ioctl.c line 1144
Quoted 8 lines
drivers/char/vt_ioctl.c +1
-1@@ -1138,7 +1138,7 @@if (old_vc_mode != vt_cons[new_console]->vc_mode) {if (vt_cons[new_console]->vc_mode ==KD_TEXT ) -unblank_screen (); +do_unblank_screen (1 );else do_blank_screen (1 ); }
How about calling resize_screen in vt.c instead in this function. This way fbcon could reset the hardware state :-)
Quoted 3 lines
How about calling
resize_screeninvt.cinstead in this function. This way fbcon could reset the hardware state :-)
Because I don't want to change the semantics in VT too much, the whole VT code is rather fragile and I want to avoid beeing invasive at this point and trigger all sort of funny side effects.
Ben.
Quoted 7 lines
Quoted 3 lines
How about calling
resize_screeninvt.cinstead in this function. This way fbcon could reset the hardware state :-)Because I don't want to change the semantics in VT too much, the whole VT code is rather fragile and I want to avoid beeing invasive at this point and trigger all sort of funny side effects.
I have been pondering the code working out a clean method. Basically you have two areas of concern with this matter. Both are in vt_ioctl.c One in vt_ioctl for the case of KDSETMODE. The other place in the same file, vt_ioctl.c, is function complete_change_console.
In functions involved in this are two functions. One is do_blank_screen. Looking at it you could just break out a new function in vt_ioctl.c. Now do_unblank_screen function is a bit trickier. It makes sense that a unblank function is called. This is where we would also call other functions to reset the display.