x86, setup: "glove box" BIOS interrupts in the video code
Impact: BIOS proofing "Glove box" off BIOS interrupts in the video code. LKML-Reference: <49DE7F79.4030106@zytor.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Rafael J. Wysocki <rjw@sisk.pl>
This commit is contained in:
H. Peter Anvin
H. Peter Anvin
parent
0a706db320
commit
cf06de7b9c
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@ -2,6 +2,7 @@
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright 2007 rPath, Inc. - All Rights Reserved
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* Copyright 2009 Intel Corporation; author H. Peter Anvin
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*
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* This file is part of the Linux kernel, and is made available under
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* the terms of the GNU General Public License version 2.
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@ -29,21 +30,21 @@ static int bios_set_mode(struct mode_info *mi)
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static int set_bios_mode(u8 mode)
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{
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u16 ax;
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struct biosregs ireg, oreg;
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u8 new_mode;
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ax = mode; /* AH=0x00 Set Video Mode */
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asm volatile(INT10
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: "+a" (ax)
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: : "ebx", "ecx", "edx", "esi", "edi");
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initregs(&ireg);
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ireg.al = mode; /* AH=0x00 Set Video Mode */
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intcall(0x10, &ireg, NULL);
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ax = 0x0f00; /* Get Current Video Mode */
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asm volatile(INT10
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: "+a" (ax)
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: : "ebx", "ecx", "edx", "esi", "edi");
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ireg.ah = 0x0f; /* Get Current Video Mode */
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intcall(0x10, &ireg, &oreg);
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do_restore = 1; /* Assume video contents were lost */
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new_mode = ax & 0x7f; /* Not all BIOSes are clean with the top bit */
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/* Not all BIOSes are clean with the top bit */
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new_mode = ireg.al & 0x7f;
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if (new_mode == mode)
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return 0; /* Mode change OK */
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@ -53,10 +54,8 @@ static int set_bios_mode(u8 mode)
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/* Mode setting failed, but we didn't end up where we
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started. That's bad. Try to revert to the original
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video mode. */
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ax = boot_params.screen_info.orig_video_mode;
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asm volatile(INT10
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: "+a" (ax)
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: : "ebx", "ecx", "edx", "esi", "edi");
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ireg.ax = boot_params.screen_info.orig_video_mode;
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intcall(0x10, &ireg, NULL);
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}
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#endif
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return -1;
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@ -2,6 +2,7 @@
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright 2007 rPath, Inc. - All Rights Reserved
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* Copyright 2009 Intel Corporation; author H. Peter Anvin
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*
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* This file is part of the Linux kernel, and is made available under
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* the terms of the GNU General Public License version 2.
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@ -31,7 +32,7 @@ static inline void vesa_store_mode_params_graphics(void) {}
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static int vesa_probe(void)
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{
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#if defined(CONFIG_VIDEO_VESA) || defined(CONFIG_FIRMWARE_EDID)
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u16 ax, cx, di;
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struct biosregs ireg, oreg;
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u16 mode;
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addr_t mode_ptr;
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struct mode_info *mi;
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@ -39,13 +40,12 @@ static int vesa_probe(void)
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video_vesa.modes = GET_HEAP(struct mode_info, 0);
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ax = 0x4f00;
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di = (size_t)&vginfo;
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asm(INT10
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: "+a" (ax), "+D" (di), "=m" (vginfo)
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: : "ebx", "ecx", "edx", "esi");
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initregs(&ireg);
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ireg.ax = 0x4f00;
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ireg.di = (size_t)&vginfo;
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intcall(0x10, &ireg, &oreg);
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if (ax != 0x004f ||
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if (ireg.ax != 0x004f ||
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vginfo.signature != VESA_MAGIC ||
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vginfo.version < 0x0102)
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return 0; /* Not present */
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@ -65,14 +65,12 @@ static int vesa_probe(void)
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memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
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ax = 0x4f01;
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cx = mode;
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di = (size_t)&vminfo;
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asm(INT10
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: "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo)
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: : "ebx", "edx", "esi");
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ireg.ax = 0x4f01;
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ireg.cx = mode;
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ireg.di = (size_t)&vminfo;
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intcall(0x10, &ireg, &oreg);
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if (ax != 0x004f)
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if (ireg.ax != 0x004f)
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continue;
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if ((vminfo.mode_attr & 0x15) == 0x05) {
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@ -111,20 +109,19 @@ static int vesa_probe(void)
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static int vesa_set_mode(struct mode_info *mode)
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{
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u16 ax, bx, cx, di;
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struct biosregs ireg, oreg;
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int is_graphic;
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u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
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memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
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ax = 0x4f01;
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cx = vesa_mode;
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di = (size_t)&vminfo;
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asm(INT10
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: "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo)
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: : "ebx", "edx", "esi");
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initregs(&ireg);
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ireg.ax = 0x4f01;
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ireg.cx = vesa_mode;
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ireg.di = (size_t)&vminfo;
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intcall(0x10, &ireg, &oreg);
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if (ax != 0x004f)
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if (oreg.ax != 0x004f)
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return -1;
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if ((vminfo.mode_attr & 0x15) == 0x05) {
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@ -141,14 +138,12 @@ static int vesa_set_mode(struct mode_info *mode)
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}
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ax = 0x4f02;
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bx = vesa_mode;
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di = 0;
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asm volatile(INT10
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: "+a" (ax), "+b" (bx), "+D" (di)
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: : "ecx", "edx", "esi");
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initregs(&ireg);
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ireg.ax = 0x4f02;
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ireg.bx = vesa_mode;
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intcall(0x10, &ireg, &oreg);
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if (ax != 0x004f)
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if (oreg.ax != 0x004f)
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return -1;
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graphic_mode = is_graphic;
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@ -171,50 +166,45 @@ static int vesa_set_mode(struct mode_info *mode)
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/* Switch DAC to 8-bit mode */
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static void vesa_dac_set_8bits(void)
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{
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struct biosregs ireg, oreg;
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u8 dac_size = 6;
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/* If possible, switch the DAC to 8-bit mode */
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if (vginfo.capabilities & 1) {
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u16 ax, bx;
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ax = 0x4f08;
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bx = 0x0800;
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asm volatile(INT10
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: "+a" (ax), "+b" (bx)
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: : "ecx", "edx", "esi", "edi");
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if (ax == 0x004f)
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dac_size = bx >> 8;
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initregs(&ireg);
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ireg.ax = 0x4f08;
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ireg.bh = 0x08;
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intcall(0x10, &ireg, &oreg);
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if (oreg.ax == 0x004f)
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dac_size = oreg.bh;
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}
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/* Set the color sizes to the DAC size, and offsets to 0 */
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boot_params.screen_info.red_size = dac_size;
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boot_params.screen_info.red_size = dac_size;
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boot_params.screen_info.green_size = dac_size;
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boot_params.screen_info.blue_size = dac_size;
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boot_params.screen_info.rsvd_size = dac_size;
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boot_params.screen_info.blue_size = dac_size;
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boot_params.screen_info.rsvd_size = dac_size;
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boot_params.screen_info.red_pos = 0;
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boot_params.screen_info.green_pos = 0;
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boot_params.screen_info.blue_pos = 0;
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boot_params.screen_info.rsvd_pos = 0;
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boot_params.screen_info.red_pos = 0;
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boot_params.screen_info.green_pos = 0;
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boot_params.screen_info.blue_pos = 0;
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boot_params.screen_info.rsvd_pos = 0;
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}
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/* Save the VESA protected mode info */
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static void vesa_store_pm_info(void)
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{
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u16 ax, bx, di, es;
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struct biosregs ireg, oreg;
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ax = 0x4f0a;
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bx = di = 0;
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asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es"
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: "=d" (es), "+a" (ax), "+b" (bx), "+D" (di)
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: : "ecx", "esi");
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initregs(&ireg);
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ireg.ax = 0x4f0a;
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intcall(0x10, &ireg, &oreg);
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if (ax != 0x004f)
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if (oreg.ax != 0x004f)
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return;
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boot_params.screen_info.vesapm_seg = es;
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boot_params.screen_info.vesapm_off = di;
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boot_params.screen_info.vesapm_seg = oreg.es;
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boot_params.screen_info.vesapm_off = oreg.di;
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}
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/*
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@ -252,7 +242,7 @@ static void vesa_store_mode_params_graphics(void)
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void vesa_store_edid(void)
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{
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#ifdef CONFIG_FIRMWARE_EDID
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u16 ax, bx, cx, dx, di;
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struct biosregs ireg, oreg;
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/* Apparently used as a nonsense token... */
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memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
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@ -260,33 +250,26 @@ void vesa_store_edid(void)
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if (vginfo.version < 0x0200)
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return; /* EDID requires VBE 2.0+ */
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ax = 0x4f15; /* VBE DDC */
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bx = 0x0000; /* Report DDC capabilities */
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cx = 0; /* Controller 0 */
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di = 0; /* ES:DI must be 0 by spec */
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initregs(&ireg);
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ireg.ax = 0x4f15; /* VBE DDC */
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/* ireg.bx = 0x0000; */ /* Report DDC capabilities */
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/* ireg.cx = 0; */ /* Controller 0 */
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ireg.es = 0; /* ES:DI must be 0 by spec */
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intcall(0x10, &ireg, &oreg);
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/* Note: The VBE DDC spec is different from the main VESA spec;
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we genuinely have to assume all registers are destroyed here. */
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asm("pushw %%es; movw %2,%%es; "INT10"; popw %%es"
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: "+a" (ax), "+b" (bx), "+c" (cx), "+D" (di)
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: : "esi", "edx");
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if (ax != 0x004f)
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if (oreg.ax != 0x004f)
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return; /* No EDID */
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/* BH = time in seconds to transfer EDD information */
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/* BL = DDC level supported */
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ax = 0x4f15; /* VBE DDC */
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bx = 0x0001; /* Read EDID */
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cx = 0; /* Controller 0 */
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dx = 0; /* EDID block number */
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di =(size_t) &boot_params.edid_info; /* (ES:)Pointer to block */
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asm(INT10
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: "+a" (ax), "+b" (bx), "+d" (dx), "=m" (boot_params.edid_info),
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"+c" (cx), "+D" (di)
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: : "esi");
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ireg.ax = 0x4f15; /* VBE DDC */
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ireg.bx = 0x0001; /* Read EDID */
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/* ireg.cx = 0; */ /* Controller 0 */
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/* ireg.dx = 0; */ /* EDID block number */
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ireg.es = ds();
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ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
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intcall(0x10, &ireg, &oreg);
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#endif /* CONFIG_FIRMWARE_EDID */
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}
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@ -2,6 +2,7 @@
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright 2007 rPath, Inc. - All Rights Reserved
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* Copyright 2009 Intel Corporation; author H. Peter Anvin
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*
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* This file is part of the Linux kernel, and is made available under
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* the terms of the GNU General Public License version 2.
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@ -39,30 +40,30 @@ static __videocard video_vga;
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/* Set basic 80x25 mode */
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static u8 vga_set_basic_mode(void)
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{
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struct biosregs ireg, oreg;
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u16 ax;
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u8 rows;
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u8 mode;
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initregs(&ireg);
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#ifdef CONFIG_VIDEO_400_HACK
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if (adapter >= ADAPTER_VGA) {
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asm volatile(INT10
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: : "a" (0x1202), "b" (0x0030)
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: "ecx", "edx", "esi", "edi");
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ireg.ax = 0x1202;
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ireg.bx = 0x0030;
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intcall(0x10, &ireg, NULL);
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}
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#endif
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ax = 0x0f00;
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asm volatile(INT10
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: "+a" (ax)
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: : "ebx", "ecx", "edx", "esi", "edi");
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mode = (u8)ax;
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intcall(0x10, &ireg, &oreg);
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mode = oreg.al;
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set_fs(0);
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rows = rdfs8(0x484); /* rows minus one */
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#ifndef CONFIG_VIDEO_400_HACK
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if ((ax == 0x5003 || ax == 0x5007) &&
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if ((oreg.ax == 0x5003 || oreg.ax == 0x5007) &&
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(rows == 0 || rows == 24))
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return mode;
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#endif
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@ -71,10 +72,8 @@ static u8 vga_set_basic_mode(void)
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mode = 3;
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/* Set the mode */
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ax = mode;
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asm volatile(INT10
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: "+a" (ax)
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: : "ebx", "ecx", "edx", "esi", "edi");
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ireg.ax = mode; /* AH=0: set mode */
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intcall(0x10, &ireg, NULL);
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do_restore = 1;
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return mode;
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}
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@ -82,43 +81,69 @@ static u8 vga_set_basic_mode(void)
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static void vga_set_8font(void)
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{
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/* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */
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struct biosregs ireg;
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initregs(&ireg);
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/* Set 8x8 font */
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asm volatile(INT10 : : "a" (0x1112), "b" (0));
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ireg.ax = 0x1112;
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/* ireg.bl = 0; */
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intcall(0x10, &ireg, NULL);
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/* Use alternate print screen */
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asm volatile(INT10 : : "a" (0x1200), "b" (0x20));
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ireg.ax = 0x1200;
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ireg.bl = 0x20;
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intcall(0x10, &ireg, NULL);
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/* Turn off cursor emulation */
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asm volatile(INT10 : : "a" (0x1201), "b" (0x34));
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ireg.ax = 0x1201;
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ireg.bl = 0x34;
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intcall(0x10, &ireg, NULL);
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/* Cursor is scan lines 6-7 */
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asm volatile(INT10 : : "a" (0x0100), "c" (0x0607));
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ireg.ax = 0x0100;
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ireg.cx = 0x0607;
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intcall(0x10, &ireg, NULL);
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}
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static void vga_set_14font(void)
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{
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/* Set 9x14 font - 80x28 on VGA */
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struct biosregs ireg;
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initregs(&ireg);
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/* Set 9x14 font */
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asm volatile(INT10 : : "a" (0x1111), "b" (0));
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ireg.ax = 0x1111;
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/* ireg.bl = 0; */
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intcall(0x10, &ireg, NULL);
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/* Turn off cursor emulation */
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asm volatile(INT10 : : "a" (0x1201), "b" (0x34));
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ireg.ax = 0x1201;
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ireg.bl = 0x34;
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intcall(0x10, &ireg, NULL);
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/* Cursor is scan lines 11-12 */
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asm volatile(INT10 : : "a" (0x0100), "c" (0x0b0c));
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ireg.ax = 0x0100;
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ireg.cx = 0x0b0c;
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intcall(0x10, &ireg, NULL);
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}
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static void vga_set_80x43(void)
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{
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/* Set 80x43 mode on VGA (not EGA) */
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struct biosregs ireg;
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initregs(&ireg);
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/* Set 350 scans */
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asm volatile(INT10 : : "a" (0x1201), "b" (0x30));
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ireg.ax = 0x1201;
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ireg.bl = 0x30;
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intcall(0x10, &ireg, NULL);
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/* Reset video mode */
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asm volatile(INT10 : : "a" (0x0003));
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ireg.ax = 0x0003;
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intcall(0x10, &ireg, NULL);
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vga_set_8font();
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}
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@ -225,8 +250,6 @@ static int vga_set_mode(struct mode_info *mode)
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*/
|
||||
static int vga_probe(void)
|
||||
{
|
||||
u16 ega_bx;
|
||||
|
||||
static const char *card_name[] = {
|
||||
"CGA/MDA/HGC", "EGA", "VGA"
|
||||
};
|
||||
|
|
@ -240,26 +263,26 @@ static int vga_probe(void)
|
|||
sizeof(ega_modes)/sizeof(struct mode_info),
|
||||
sizeof(vga_modes)/sizeof(struct mode_info),
|
||||
};
|
||||
u8 vga_flag;
|
||||
|
||||
asm(INT10
|
||||
: "=b" (ega_bx)
|
||||
: "a" (0x1200), "b" (0x10) /* Check EGA/VGA */
|
||||
: "ecx", "edx", "esi", "edi");
|
||||
struct biosregs ireg, oreg;
|
||||
|
||||
initregs(&ireg);
|
||||
|
||||
ireg.ax = 0x1200;
|
||||
ireg.bl = 0x10; /* Check EGA/VGA */
|
||||
intcall(0x10, &ireg, &oreg);
|
||||
|
||||
#ifndef _WAKEUP
|
||||
boot_params.screen_info.orig_video_ega_bx = ega_bx;
|
||||
boot_params.screen_info.orig_video_ega_bx = oreg.bx;
|
||||
#endif
|
||||
|
||||
/* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */
|
||||
if ((u8)ega_bx != 0x10) {
|
||||
if (oreg.bl != 0x10) {
|
||||
/* EGA/VGA */
|
||||
asm(INT10
|
||||
: "=a" (vga_flag)
|
||||
: "a" (0x1a00)
|
||||
: "ebx", "ecx", "edx", "esi", "edi");
|
||||
ireg.ax = 0x1a00;
|
||||
intcall(0x10, &ireg, &oreg);
|
||||
|
||||
if (vga_flag == 0x1a) {
|
||||
if (oreg.al == 0x1a) {
|
||||
adapter = ADAPTER_VGA;
|
||||
#ifndef _WAKEUP
|
||||
boot_params.screen_info.orig_video_isVGA = 1;
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@
|
|||
*
|
||||
* Copyright (C) 1991, 1992 Linus Torvalds
|
||||
* Copyright 2007 rPath, Inc. - All Rights Reserved
|
||||
* Copyright 2009 Intel Corporation; author H. Peter Anvin
|
||||
*
|
||||
* This file is part of the Linux kernel, and is made available under
|
||||
* the terms of the GNU General Public License version 2.
|
||||
|
|
@ -18,33 +19,29 @@
|
|||
|
||||
static void store_cursor_position(void)
|
||||
{
|
||||
u16 curpos;
|
||||
u16 ax, bx;
|
||||
struct biosregs ireg, oreg;
|
||||
|
||||
ax = 0x0300;
|
||||
bx = 0;
|
||||
asm(INT10
|
||||
: "=d" (curpos), "+a" (ax), "+b" (bx)
|
||||
: : "ecx", "esi", "edi");
|
||||
initregs(&ireg);
|
||||
ireg.ah = 0x03;
|
||||
intcall(0x10, &ireg, &oreg);
|
||||
|
||||
boot_params.screen_info.orig_x = curpos;
|
||||
boot_params.screen_info.orig_y = curpos >> 8;
|
||||
boot_params.screen_info.orig_x = oreg.dl;
|
||||
boot_params.screen_info.orig_y = oreg.dh;
|
||||
}
|
||||
|
||||
static void store_video_mode(void)
|
||||
{
|
||||
u16 ax, page;
|
||||
struct biosregs ireg, oreg;
|
||||
|
||||
/* N.B.: the saving of the video page here is a bit silly,
|
||||
since we pretty much assume page 0 everywhere. */
|
||||
ax = 0x0f00;
|
||||
asm(INT10
|
||||
: "+a" (ax), "=b" (page)
|
||||
: : "ecx", "edx", "esi", "edi");
|
||||
initregs(&ireg);
|
||||
ireg.ah = 0x0f;
|
||||
intcall(0x10, &ireg, &oreg);
|
||||
|
||||
/* Not all BIOSes are clean with respect to the top bit */
|
||||
boot_params.screen_info.orig_video_mode = ax & 0x7f;
|
||||
boot_params.screen_info.orig_video_page = page >> 8;
|
||||
boot_params.screen_info.orig_video_mode = oreg.al & 0x7f;
|
||||
boot_params.screen_info.orig_video_page = oreg.bh;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -257,7 +254,7 @@ static void restore_screen(void)
|
|||
int y;
|
||||
addr_t dst = 0;
|
||||
u16 *src = saved.data;
|
||||
u16 ax, bx, dx;
|
||||
struct biosregs ireg;
|
||||
|
||||
if (graphic_mode)
|
||||
return; /* Can't restore onto a graphic mode */
|
||||
|
|
@ -296,12 +293,11 @@ static void restore_screen(void)
|
|||
}
|
||||
|
||||
/* Restore cursor position */
|
||||
ax = 0x0200; /* Set cursor position */
|
||||
bx = 0; /* Page number (<< 8) */
|
||||
dx = (saved.cury << 8)+saved.curx;
|
||||
asm volatile(INT10
|
||||
: "+a" (ax), "+b" (bx), "+d" (dx)
|
||||
: : "ecx", "esi", "edi");
|
||||
initregs(&ireg);
|
||||
ireg.ah = 0x02; /* Set cursor position */
|
||||
ireg.dh = saved.cury;
|
||||
ireg.dl = saved.curx;
|
||||
intcall(0x10, &ireg, NULL);
|
||||
}
|
||||
#else
|
||||
#define save_screen() ((void)0)
|
||||
|
|
|
|||
|
|
@ -112,20 +112,6 @@ extern int force_x, force_y; /* Don't query the BIOS for cols/rows */
|
|||
extern int do_restore; /* Restore screen contents */
|
||||
extern int graphic_mode; /* Graphics mode with linear frame buffer */
|
||||
|
||||
/*
|
||||
* int $0x10 is notorious for touching registers it shouldn't.
|
||||
* gcc doesn't like %ebp being clobbered, so define it as a push/pop
|
||||
* sequence here.
|
||||
*
|
||||
* A number of systems, including the original PC can clobber %bp in
|
||||
* certain circumstances, like when scrolling. There exists at least
|
||||
* one Trident video card which could clobber DS under a set of
|
||||
* circumstances that we are unlikely to encounter (scrolling when
|
||||
* using an extended graphics mode of more than 800x600 pixels), but
|
||||
* it's cheap insurance to deal with that here.
|
||||
*/
|
||||
#define INT10 "pushl %%ebp; pushw %%ds; int $0x10; popw %%ds; popl %%ebp"
|
||||
|
||||
/* Accessing VGA indexed registers */
|
||||
static inline u8 in_idx(u16 port, u8 index)
|
||||
{
|
||||
|
|
|
|||
Reference in New Issue