[PATCH 1/3: FBDEV: VGA State Save/Restore module

[PATCH 1/3: FBDEV: VGA State Save/Restore module

[Antonino Daplas]

[-- Attachment #1: Type: text/plain, Size: 1019 bytes --]

Hi,

Attached is a patch against linux-2.5.50 + James Simmons fbdev.diff to
save and restore the VGA state. This includes character maps (plane
0-3), the colormap, and the video mode.  This can be used in fb_open()
and fb_release() to go back to VGA text/graphics mode.

Usage:

struct fb_vgastate state;

/* To save VGA state */
state.flags = VGA_SAVE_MODE | VGA_SAVE_CMAP | VGA_SAVE_FONTS;
fb_save_vga(&state);

/* To restore VGA state */
fb_restore_vga(&state);

Limitations:
1.  Restoring the VGA state from high-resolution graphics mode may
result in a corrupt display which can be corrected by switching
consoles.  May need a screen redraw at this point.  Restoring from VGA
graphics mode to text mode and vice versa is okay.

2. Assumes some things about the hardware which is not universally
correct:  VGA memory base is at 0xA0000, memory size is 64KB, the
hardware palette is readable, etc. 

Any comments welcome.

Tony

PS:  Please reverse the early patch I submitted if it was applied --
vgastate.diff





[-- Attachment #2: vgastate1.diff --]
[-- Type: text/x-patch, Size: 16077 bytes --]

diff -Naur linux-2.5.50-js/drivers/video/Makefile linux/drivers/video/Makefile
--- linux-2.5.50-js/drivers/video/Makefile	2002-12-04 15:15:25.000000000 +0000
+++ linux/drivers/video/Makefile	2002-12-04 15:14:40.000000000 +0000
@@ -6,7 +6,7 @@
 # This list comes from 'grep -l EXPORT_SYMBOL *.[hc]'.
 
 export-objs    	:= fbmem.o fbcmap.o fbmon.o modedb.o softcursor.o cfbfillrect.o \
-		   cfbcopyarea.o cfbimgblt.o cyber2000fb.o 
+		   cfbcopyarea.o cfbimgblt.o cyber2000fb.o vgastate.o
 
 # Each configuration option enables a list of files.
 
diff -Naur linux-2.5.50-js/drivers/video/vgastate.c linux/drivers/video/vgastate.c
--- linux-2.5.50-js/drivers/video/vgastate.c	1970-01-01 00:00:00.000000000 +0000
+++ linux/drivers/video/vgastate.c	2002-12-04 15:14:17.000000000 +0000
@@ -0,0 +1,438 @@
+/*
+ * linux/include/video/vgastate.c -- VGA state save/restore
+ *
+ * Copyright 2002 James Simmons
+ * 
+ * Copyright history from vga16fb.c:
+ *	Copyright 1999 Ben Pfaff and Petr Vandrovec
+ *	Based on VGA info at http://www.goodnet.com/~tinara/FreeVGA/home.htm
+ *	Based on VESA framebuffer (c) 1998 Gerd Knorr
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.  
+ *
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/fb.h>
+
+#include "vga.h"
+
+static inline unsigned char vga_rcrtcs(caddr_t regbase, unsigned short iobase, 
+				       unsigned char reg)
+{
+	vga_w(regbase, iobase + 0x4, reg);
+	return vga_r(regbase, iobase + 0x5);
+}
+
+static inline void vga_wcrtcs(caddr_t regbase, unsigned short iobase, 
+			      unsigned char reg, unsigned char val)
+{
+	vga_w(regbase, iobase + 0x4, reg);
+	vga_w(regbase, iobase + 0x5, val);
+}
+
+static void save_vga_text(struct fb_vgastate *state)
+{
+	int i;
+	u8 misc, attr10, gr4, gr5, gr6, seq1, seq2, seq4;
+
+	/* if in graphics mode, no need to save */
+	attr10 = vga_rattr(state->vgabase, 0x10);
+	if (attr10 & 1)
+		return;
+	
+	/* save regs */
+	misc = vga_r(state->vgabase, VGA_MIS_R);
+	gr4 = vga_rgfx(state->vgabase, VGA_GFX_PLANE_READ);
+	gr5 = vga_rgfx(state->vgabase, VGA_GFX_MODE);
+	gr6 = vga_rgfx(state->vgabase, VGA_GFX_MISC);
+	seq2 = vga_rseq(state->vgabase, VGA_SEQ_PLANE_WRITE);
+	seq4 = vga_rseq(state->vgabase, VGA_SEQ_MEMORY_MODE);
+	
+	/* force graphics mode */
+	vga_w(state->vgabase, VGA_MIS_W, misc | 1);
+
+	/* blank screen */
+	seq1 = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 | 1 << 5);
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
+
+	/* save font 0 */
+	if (state->flags & VGA_SAVE_FONT0) {
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x4);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x2);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 8 * 8192; i++) 
+			state->vga_font0[i] = vga_r(state->fbbase, i);
+	}
+	/* save font 1 */
+	if (state->flags & VGA_SAVE_FONT1) {
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x8);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x3);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 8 * 8192; i++) 
+			state->vga_font1[i] = vga_r(state->fbbase, i);
+	}
+	/* save font 2 */
+	if (state->flags & VGA_SAVE_TEXT) {
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x1);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 2 * 8192; i++) 
+			state->vga_text[i] = vga_r(state->fbbase, i);
+
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x2);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x1);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 2 * 8192; i++) 
+			state->vga_text[i] = vga_r(state->fbbase + 
+						    2 * 8192, i);
+	}
+
+	/* restore regs */
+	vga_wattr(state->vgabase, 0x10, attr10);
+
+	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, seq2);
+	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, seq4);
+
+	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, gr4);
+	vga_wgfx(state->vgabase, VGA_GFX_MODE, gr5);
+	vga_wgfx(state->vgabase, VGA_GFX_MISC, gr6);
+	vga_w(state->vgabase, VGA_MIS_W, misc);
+
+	/* unblank screen */
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 & ~(1 << 5));
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
+
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1);
+}
+
+static void restore_vga_text(struct fb_vgastate *state)
+{
+	int i;
+	u8 misc, gr1, gr3, gr4, gr5, gr6, gr8; 
+	u8 seq1, seq2, seq4;
+
+	/* save regs */
+	misc = vga_r(state->vgabase, VGA_MIS_R);
+	gr1 = vga_rgfx(state->vgabase, VGA_GFX_SR_ENABLE);
+	gr3 = vga_rgfx(state->vgabase, VGA_GFX_DATA_ROTATE);
+	gr4 = vga_rgfx(state->vgabase, VGA_GFX_PLANE_READ);
+	gr5 = vga_rgfx(state->vgabase, VGA_GFX_MODE);
+	gr6 = vga_rgfx(state->vgabase, VGA_GFX_MISC);
+	gr8 = vga_rgfx(state->vgabase, VGA_GFX_BIT_MASK);
+	seq2 = vga_rseq(state->vgabase, VGA_SEQ_PLANE_WRITE);
+	seq4 = vga_rseq(state->vgabase, VGA_SEQ_MEMORY_MODE);
+	
+	/* force graphics mode */
+	vga_w(state->vgabase, VGA_MIS_W, misc | 1);
+
+	/* blank screen */
+	seq1 = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 | 1 << 5);
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
+
+	if (state->depth == 4) {
+		vga_wgfx(state->vgabase, VGA_GFX_DATA_ROTATE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_BIT_MASK, 0xff);
+		vga_wgfx(state->vgabase, VGA_GFX_SR_ENABLE, 0x00);
+	}
+	/* restore font 0 */
+	if (state->flags & VGA_SAVE_FONT0) {
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x4);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x2);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 8 * 8192; i++) 
+			vga_w(state->fbbase, i, state->vga_font0[i]);
+	}
+	/* restore font 1 */
+	if (state->flags & VGA_SAVE_FONT1) {
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x8);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x3);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 8 * 8192; i++) 
+			vga_w(state->fbbase, i, state->vga_font1[i]);
+	}
+	/* restore font 2 */
+	if (state->flags & VGA_SAVE_TEXT) {
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x1);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 2 * 8192; i++) 
+			vga_w(state->fbbase, i, state->vga_text[i]);
+		
+		vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x2);
+		vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
+		vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x1);
+		vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
+		vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
+		for (i = 0; i < 2 * 8192; i++) 
+			vga_w(state->fbbase + 2 * 8192, i, 
+			      state->vga_text[i]);
+	}
+	/* unblank screen */
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 & ~(1 << 5));
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
+
+	/* restore regs */
+	vga_w(state->vgabase, VGA_MIS_W, misc);
+
+	vga_wgfx(state->vgabase, VGA_GFX_SR_ENABLE, gr1);
+	vga_wgfx(state->vgabase, VGA_GFX_DATA_ROTATE, gr3);
+	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, gr4);
+	vga_wgfx(state->vgabase, VGA_GFX_MODE, gr5);
+	vga_wgfx(state->vgabase, VGA_GFX_MISC, gr6);
+	vga_wgfx(state->vgabase, VGA_GFX_BIT_MASK, gr8);
+
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1);
+	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, seq2);
+	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, seq4);
+}
+			      
+static void save_vga_mode(struct fb_vgastate *state)
+{
+	unsigned short iobase;
+	int i;
+
+	state->misc = vga_r(state->vgabase, VGA_MIS_R);
+	if (state->misc & 1)
+		iobase = 0x3d0;
+	else
+		iobase = 0x3b0;
+
+	for (i = 0; i < state->num_crtc; i++) 
+		state->crtc[i] = vga_rcrtcs(state->vgabase, iobase, i);
+	
+	vga_r(state->vgabase, iobase + 0xa); 
+	vga_w(state->vgabase, VGA_ATT_W, 0x00);
+	for (i = 0; i < state->num_attr; i++) {
+		vga_r(state->vgabase, iobase + 0xa);
+		state->attr[i] = vga_rattr(state->vgabase, i);
+	}
+	vga_r(state->vgabase, iobase + 0xa);
+	vga_w(state->vgabase, VGA_ATT_W, 0x20);
+
+	for (i = 0; i < state->num_gfx; i++) 
+		state->gfx[i] = vga_rgfx(state->vgabase, i);
+
+	for (i = 0; i < state->num_seq; i++) 
+		state->seq[i] = vga_rseq(state->vgabase, i);
+}
+
+static void restore_vga_mode(struct fb_vgastate *state)
+{
+	unsigned short iobase;
+	int i;
+
+	vga_w(state->vgabase, VGA_MIS_W, state->misc);
+
+	if (state->misc & 1)
+		iobase = 0x3d0;
+	else
+		iobase = 0x3b0;
+
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, 
+		 state->seq[VGA_SEQ_CLOCK_MODE] | 0x20);
+
+	for (i = 2; i < state->num_seq; i++) 
+		vga_wseq(state->vgabase, i, state->seq[i]);
+
+	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
+
+	/* unprotect vga regs */
+	vga_wcrtcs(state->vgabase, iobase, 17, state->crtc[17] & ~0x80);
+	for (i = 0; i < state->num_crtc; i++) 
+		vga_wcrtcs(state->vgabase, iobase, i, state->crtc[i]);
+	
+	for (i = 0; i < state->num_gfx; i++) 
+		vga_wgfx(state->vgabase, i, state->gfx[i]);
+
+	vga_r(state->vgabase, iobase + 0xa);
+	vga_w(state->vgabase, VGA_ATT_W, 0x00);
+	for (i = 0; i < state->num_attr; i++) {
+		vga_r(state->vgabase, iobase + 0xa);
+		vga_wattr(state->vgabase, i, state->attr[i]);
+	}
+
+	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, 
+		 state->seq[VGA_SEQ_CLOCK_MODE]);
+
+	vga_r(state->vgabase, iobase + 0xa);
+	vga_w(state->vgabase, VGA_ATT_W, 0x20);
+}
+
+static void save_vga_cmap(struct fb_vgastate *state)
+{
+	int i;
+
+	vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
+	
+	/* assumes DAC is readable and writable */
+	vga_w(state->vgabase, VGA_PEL_IR, 0x00);
+	for (i = 0; i < 768; i++)
+		state->vga_cmap[i] = vga_r(state->vgabase, VGA_PEL_D);
+}
+
+static void restore_vga_cmap(struct fb_vgastate *state)
+{
+	int i;
+
+	vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
+
+	vga_w(state->vgabase, VGA_PEL_IW, 0x00);
+	for (i = 0; i < 768; i++)
+		vga_w(state->vgabase, VGA_PEL_D, state->vga_cmap[i]);
+}
+
+static void vga_cleanup(struct fb_vgastate *state)
+{
+	if (state->vga_font0) 
+		kfree(state->vga_font0);
+	if (state->vga_font1) 
+		kfree(state->vga_font1);
+	if (state->vga_text)
+		kfree(state->vga_text);
+	if (state->fbbase)
+		iounmap(state->fbbase);
+	if (state->vga_cmap)
+		kfree(state->vga_cmap);
+	if (state->attr)
+		kfree(state->attr);
+	if (state->crtc)
+		kfree(state->crtc);
+	if (state->gfx)
+		kfree(state->gfx);
+	if (state->seq)
+		kfree(state->seq);
+}
+		
+int fb_save_vga(struct fb_vgastate *state)
+{
+	state->vga_font0 = NULL;
+	state->vga_font1 = NULL;
+	state->vga_text = NULL;
+	state->vga_cmap = NULL;
+	state->attr = NULL;
+	state->crtc = NULL;
+	state->gfx = NULL;
+	state->seq = NULL;
+		
+	if (state->flags & VGA_SAVE_CMAP) {
+		state->vga_cmap = kmalloc(768, GFP_KERNEL);
+		if (!state->vga_cmap) {
+			vga_cleanup(state);
+			return 1;
+		}
+		save_vga_cmap(state);
+	}
+
+	if (state->flags & VGA_SAVE_MODE) {
+		if (state->num_attr < 21)
+			state->num_attr = 21;
+		if (state->num_crtc < 25)
+			state->num_crtc = 25;
+		if (state->num_gfx < 9)
+			state->num_gfx = 9;
+		if (state->num_seq < 5)
+			state->num_seq = 5;
+		state->attr = kmalloc(state->num_attr, GFP_KERNEL);
+		state->crtc = kmalloc(state->num_crtc, GFP_KERNEL);
+		state->gfx = kmalloc(state->num_gfx, GFP_KERNEL);
+		state->seq = kmalloc(state->num_seq, GFP_KERNEL);
+		if (!state->attr || !state->crtc || !state->gfx ||
+		    !state->seq) {
+			vga_cleanup(state);
+			return 1;
+		}
+		save_vga_mode(state);
+	}
+
+	if (state->flags & VGA_SAVE_FONT0) {
+		state->vga_font0 = kmalloc(8192 * 8, GFP_KERNEL);
+		if (!state->vga_font0) {
+			vga_cleanup(state);
+			return 1;
+		}
+	}
+	if (state->flags & VGA_SAVE_FONT1) {
+		state->vga_font1 = kmalloc(8192 * 8, GFP_KERNEL);
+		if (!state->vga_font1) {
+			vga_cleanup(state);
+			return 1;
+		}
+	}
+	if (state->flags & VGA_SAVE_TEXT) {
+		state->vga_text = kmalloc(8192 * 4, GFP_KERNEL);
+		if (!state->vga_text) {
+			vga_cleanup(state);
+			return 1;
+		}
+	}
+	if (state->flags & VGA_SAVE_FONTS) {
+		state->fbbase = ioremap(0xA0000, 8 * 8192);
+		if (!state->fbbase) {
+			vga_cleanup(state);
+			return 1;
+		}
+		save_vga_text(state);
+		iounmap(state->fbbase);
+		state->fbbase = NULL;
+	}
+	return 0;
+}
+
+int fb_restore_vga (struct fb_vgastate *state)
+{
+	if (state->flags & VGA_SAVE_MODE)
+		restore_vga_mode(state);
+
+	if (state->flags & VGA_SAVE_FONTS) {
+		state->fbbase = ioremap(0xA0000, 8 * 8192);
+		if (!state->fbbase) {
+			vga_cleanup(state);
+			return 1;
+		}
+		restore_vga_text(state);
+	}
+
+	if (state->flags & VGA_SAVE_CMAP)
+		restore_vga_cmap(state);
+
+	vga_cleanup(state);
+	return 0;
+}
+
+#ifdef MODULE
+int init_module(void) { return 0; };
+void cleanup_module(void) {};
+#endif
+
+EXPORT_SYMBOL(fb_save_vga);
+EXPORT_SYMBOL(fb_restore_vga);
+
+MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
+MODULE_DESCRIPTION("VGA State Save/Restore");
+MODULE_LICENSE("GPL");
+
diff -Naur linux-2.5.50-js/include/linux/fb.h linux/include/linux/fb.h
--- linux-2.5.50-js/include/linux/fb.h	2002-12-04 15:07:13.000000000 +0000
+++ linux/include/linux/fb.h	2002-12-04 15:20:00.000000000 +0000
@@ -321,6 +321,37 @@
 	struct fb_image	image;	/* Cursor image */
 };
 
+/* VGA State Save and Restore */
+#define VGA_SAVE_FONT0 1  /* save/restore plane 2 fonts   */
+#define VGA_SAVE_FONT1 2  /* save/restore plane 3 fonts   */
+#define VGA_SAVE_TEXT  4  /* save/restore plane 0/1 fonts */
+#define VGA_SAVE_FONTS 7  /* save/restore all fonts       */
+#define VGA_SAVE_MODE  8  /* save/restore video mode      */
+#define VGA_SAVE_CMAP  16 /* save/restore color map/DAC  */
+
+struct fb_vgastate {
+	caddr_t vgabase;         /* mmio base, if supported                 */
+	__u32 flags;             /* what state/s to save (see VGA_SAVE_*)   */ 
+	__u32 depth;             /* current fb depth, not important         */
+	__u32 num_attr;          /* number of att registers, 0 for default  */
+	__u32 num_crtc;          /* number of crt registers, 0 for default  */
+	__u32 num_gfx;           /* number of gfx registers, 0 for default  */
+	__u32 num_seq;           /* number of seq registers, 0 for default  */
+	caddr_t fbbase;          /*    -- DO NOT ALTER STARTING HERE --     */
+	__u8 *vga_font0;         
+	__u8 *vga_font1;         
+	__u8 *vga_text;         
+	__u8 *vga_cmap;          
+	__u8 *attr;               
+	__u8 *crtc;              
+	__u8 *gfx;               
+	__u8 *seq;               
+	__u8 misc;               
+};
+
+extern int fb_save_vga(struct fb_vgastate *state);
+extern int fb_restore_vga(struct fb_vgastate *state);
+
 #ifdef __KERNEL__
 
 #include <linux/fs.h>

Re: [Linux-fbdev-devel] [PATCH 1/3: FBDEV: VGA State Save/Restore module

[James Simmons]

> Limitations:
> 1.  Restoring the VGA state from high-resolution graphics mode may
> result in a corrupt display which can be corrected by switching
> consoles.  May need a screen redraw at this point.  Restoring from VGA
> graphics mode to text mode and vice versa is okay.
> 
> 2. Assumes some things about the hardware which is not universally
> correct:  VGA memory base is at 0xA0000, memory size is 64KB, the
> hardware palette is readable, etc. 
> 
> Any comments welcome.

One thing I like to suggest. I like to move the vga code in fb.h to vga.h. 
Alot of fbdev devices don't have a VGA core. 

Re: [Linux-fbdev-devel] [PATCH 1/3: FBDEV: VGA State Save/Restore module

[Antonino Daplas]

On Thu, 2002-12-05 at 22:31, James Simmons wrote:
> 
> > Limitations:
> > 1.  Restoring the VGA state from high-resolution graphics mode may
> > result in a corrupt display which can be corrected by switching
> > consoles.  May need a screen redraw at this point.  Restoring from VGA
> > graphics mode to text mode and vice versa is okay.
> > 
> > 2. Assumes some things about the hardware which is not universally
> > correct:  VGA memory base is at 0xA0000, memory size is 64KB, the
> > hardware palette is readable, etc. 
> > 
> > Any comments welcome.
> 
> One thing I like to suggest. I like to move the vga code in fb.h to vga.h. 
> Alot of fbdev devices don't have a VGA core. 
> 
> 

Only the structure definition of fb_vgastate is in fb.h.  For drivers
without a vga core, they'll just won't link to it and it won't be
compiled.  Plus, vga.h is not a common header (not located in
include/asm or include/linux) and it contains a lot of declarations and
definitions which are irrelevant to most drivers or are already
duplicated.  This will be messier, I think.  

Maybe we can just enclose it in a macro, something like:

#ifdef FBDEV_HAS_VGACORE
...
#endif

Tony

Re: [Linux-fbdev-devel] [PATCH 1/3: FBDEV: VGA State Save/Restore module

[James Simmons]

> > One thing I like to suggest. I like to move the vga code in fb.h to vga.h. 
> > Alot of fbdev devices don't have a VGA core. 
> > 
> > 
> 
> Only the structure definition of fb_vgastate is in fb.h.  For drivers
> without a vga core, they'll just won't link to it and it won't be
> compiled.  Plus, vga.h is not a common header (not located in
> include/asm or include/linux) and it contains a lot of declarations and
> definitions which are irrelevant to most drivers or are already
> duplicated.  This will be messier, I think.  

I like to move vga.h to include/video. And yes I like to clean it up. The 
reason is I like to implement the function in vga.h and some in vgastate 
into vgacon.c. It would be nice if vgacon could support different hardware 
states per VC instead of changing every virtual console for everything. 
The other dream is I like to see vgacon become firmware independent. 

> Maybe we can just enclose it in a macro, something like:
> 
> #ifdef FBDEV_HAS_VGACORE
> ...
> #endif
 
Yuck :-(

Re: [Linux-fbdev-devel] [PATCH 1/3: FBDEV: VGA State Save/Restore module

[Antonino Daplas]

On Fri, 2002-12-06 at 05:53, James Simmons wrote:
> > 
> > Only the structure definition of fb_vgastate is in fb.h.  For drivers
> > without a vga core, they'll just won't link to it and it won't be
> > compiled.  Plus, vga.h is not a common header (not located in
> > include/asm or include/linux) and it contains a lot of declarations and
> > definitions which are irrelevant to most drivers or are already
> > duplicated.  This will be messier, I think.  
> 
> I like to move vga.h to include/video. And yes I like to clean it up. The 
> reason is I like to implement the function in vga.h and some in vgastate 
> into vgacon.c. It would be nice if vgacon could support different hardware 
> states per VC instead of changing every virtual console for everything. 
> The other dream is I like to see vgacon become firmware independent. 
> 
OK.

Tony