1 files changed, 279 insertions, 0 deletions
diff --git a/arch/x86/boot/video-vesa.c b/arch/x86/boot/video-vesa.c
new file mode 100644
index 000000000..7e185977a
--- /dev/null
+++ b/arch/x86/boot/video-vesa.c
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *   Copyright 2007 rPath, Inc. - All Rights Reserved
+ *   Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * VESA text modes
+ */
+
+#include "boot.h"
+#include "video.h"
+#include "vesa.h"
+#include "string.h"
+
+/* VESA information */
+static struct vesa_general_info vginfo;
+static struct vesa_mode_info vminfo;
+
+static __videocard video_vesa;
+
+#ifndef _WAKEUP
+static void vesa_store_mode_params_graphics(void);
+#else /* _WAKEUP */
+static inline void vesa_store_mode_params_graphics(void) {}
+#endif /* _WAKEUP */
+
+static int vesa_probe(void)
+{
+	struct biosregs ireg, oreg;
+	u16 mode;
+	addr_t mode_ptr;
+	struct mode_info *mi;
+	int nmodes = 0;
+
+	video_vesa.modes = GET_HEAP(struct mode_info, 0);
+
+	initregs(&ireg);
+	ireg.ax = 0x4f00;
+	ireg.di = (size_t)&vginfo;
+	intcall(0x10, &ireg, &oreg);
+
+	if (oreg.ax != 0x004f ||
+	    vginfo.signature != VESA_MAGIC ||
+	    vginfo.version < 0x0102)
+		return 0;	/* Not present */
+
+	set_fs(vginfo.video_mode_ptr.seg);
+	mode_ptr = vginfo.video_mode_ptr.off;
+
+	while ((mode = rdfs16(mode_ptr)) != 0xffff) {
+		mode_ptr += 2;
+
+		if (!heap_free(sizeof(struct mode_info)))
+			break;	/* Heap full, can't save mode info */
+
+		if (mode & ~0x1ff)
+			continue;
+
+		memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
+
+		ireg.ax = 0x4f01;
+		ireg.cx = mode;
+		ireg.di = (size_t)&vminfo;
+		intcall(0x10, &ireg, &oreg);
+
+		if (oreg.ax != 0x004f)
+			continue;
+
+		if ((vminfo.mode_attr & 0x15) == 0x05) {
+			/* Text Mode, TTY BIOS supported,
+			   supported by hardware */
+			mi = GET_HEAP(struct mode_info, 1);
+			mi->mode  = mode + VIDEO_FIRST_VESA;
+			mi->depth = 0; /* text */
+			mi->x     = vminfo.h_res;
+			mi->y     = vminfo.v_res;
+			nmodes++;
+		} else if ((vminfo.mode_attr & 0x99) == 0x99 &&
+			   (vminfo.memory_layout == 4 ||
+			    vminfo.memory_layout == 6) &&
+			   vminfo.memory_planes == 1) {
+#ifdef CONFIG_FB_BOOT_VESA_SUPPORT
+			/* Graphics mode, color, linear frame buffer
+			   supported.  Only register the mode if
+			   if framebuffer is configured, however,
+			   otherwise the user will be left without a screen. */
+			mi = GET_HEAP(struct mode_info, 1);
+			mi->mode = mode + VIDEO_FIRST_VESA;
+			mi->depth = vminfo.bpp;
+			mi->x = vminfo.h_res;
+			mi->y = vminfo.v_res;
+			nmodes++;
+#endif
+		}
+	}
+
+	return nmodes;
+}
+
+static int vesa_set_mode(struct mode_info *mode)
+{
+	struct biosregs ireg, oreg;
+	int is_graphic;
+	u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
+
+	memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
+
+	initregs(&ireg);
+	ireg.ax = 0x4f01;
+	ireg.cx = vesa_mode;
+	ireg.di = (size_t)&vminfo;
+	intcall(0x10, &ireg, &oreg);
+
+	if (oreg.ax != 0x004f)
+		return -1;
+
+	if ((vminfo.mode_attr & 0x15) == 0x05) {
+		/* It's a supported text mode */
+		is_graphic = 0;
+#ifdef CONFIG_FB_BOOT_VESA_SUPPORT
+	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
+		/* It's a graphics mode with linear frame buffer */
+		is_graphic = 1;
+		vesa_mode |= 0x4000; /* Request linear frame buffer */
+#endif
+	} else {
+		return -1;	/* Invalid mode */
+	}
+
+
+	initregs(&ireg);
+	ireg.ax = 0x4f02;
+	ireg.bx = vesa_mode;
+	intcall(0x10, &ireg, &oreg);
+
+	if (oreg.ax != 0x004f)
+		return -1;
+
+	graphic_mode = is_graphic;
+	if (!is_graphic) {
+		/* Text mode */
+		force_x = mode->x;
+		force_y = mode->y;
+		do_restore = 1;
+	} else {
+		/* Graphics mode */
+		vesa_store_mode_params_graphics();
+	}
+
+	return 0;
+}
+
+
+#ifndef _WAKEUP
+
+/* Switch DAC to 8-bit mode */
+static void vesa_dac_set_8bits(void)
+{
+	struct biosregs ireg, oreg;
+	u8 dac_size = 6;
+
+	/* If possible, switch the DAC to 8-bit mode */
+	if (vginfo.capabilities & 1) {
+		initregs(&ireg);
+		ireg.ax = 0x4f08;
+		ireg.bh = 0x08;
+		intcall(0x10, &ireg, &oreg);
+		if (oreg.ax == 0x004f)
+			dac_size = oreg.bh;
+	}
+
+	/* Set the color sizes to the DAC size, and offsets to 0 */
+	boot_params.screen_info.red_size   = dac_size;
+	boot_params.screen_info.green_size = dac_size;
+	boot_params.screen_info.blue_size  = dac_size;
+	boot_params.screen_info.rsvd_size  = dac_size;
+
+	boot_params.screen_info.red_pos    = 0;
+	boot_params.screen_info.green_pos  = 0;
+	boot_params.screen_info.blue_pos   = 0;
+	boot_params.screen_info.rsvd_pos   = 0;
+}
+
+/* Save the VESA protected mode info */
+static void vesa_store_pm_info(void)
+{
+	struct biosregs ireg, oreg;
+
+	initregs(&ireg);
+	ireg.ax = 0x4f0a;
+	intcall(0x10, &ireg, &oreg);
+
+	if (oreg.ax != 0x004f)
+		return;
+
+	boot_params.screen_info.vesapm_seg = oreg.es;
+	boot_params.screen_info.vesapm_off = oreg.di;
+}
+
+/*
+ * Save video mode parameters for graphics mode
+ */
+static void vesa_store_mode_params_graphics(void)
+{
+	/* Tell the kernel we're in VESA graphics mode */
+	boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
+
+	/* Mode parameters */
+	boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
+	boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
+	boot_params.screen_info.lfb_width = vminfo.h_res;
+	boot_params.screen_info.lfb_height = vminfo.v_res;
+	boot_params.screen_info.lfb_depth = vminfo.bpp;
+	boot_params.screen_info.pages = vminfo.image_planes;
+	boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
+	memcpy(&boot_params.screen_info.red_size,
+	       &vminfo.rmask, 8);
+
+	/* General parameters */
+	boot_params.screen_info.lfb_size = vginfo.total_memory;
+
+	if (vminfo.bpp <= 8)
+		vesa_dac_set_8bits();
+
+	vesa_store_pm_info();
+}
+
+/*
+ * Save EDID information for the kernel; this is invoked, separately,
+ * after mode-setting.
+ */
+void vesa_store_edid(void)
+{
+#ifdef CONFIG_FIRMWARE_EDID
+	struct biosregs ireg, oreg;
+
+	/* Apparently used as a nonsense token... */
+	memset(&boot_params.edid_info, 0x13, sizeof(boot_params.edid_info));
+
+	if (vginfo.version < 0x0200)
+		return;		/* EDID requires VBE 2.0+ */
+
+	initregs(&ireg);
+	ireg.ax = 0x4f15;		/* VBE DDC */
+	/* ireg.bx = 0x0000; */		/* Report DDC capabilities */
+	/* ireg.cx = 0;	*/		/* Controller 0 */
+	ireg.es = 0;			/* ES:DI must be 0 by spec */
+	intcall(0x10, &ireg, &oreg);
+
+	if (oreg.ax != 0x004f)
+		return;		/* No EDID */
+
+	/* BH = time in seconds to transfer EDD information */
+	/* BL = DDC level supported */
+
+	ireg.ax = 0x4f15;		/* VBE DDC */
+	ireg.bx = 0x0001;		/* Read EDID */
+	/* ireg.cx = 0; */		/* Controller 0 */
+	/* ireg.dx = 0;	*/		/* EDID block number */
+	ireg.es = ds();
+	ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
+	intcall(0x10, &ireg, &oreg);
+#endif /* CONFIG_FIRMWARE_EDID */
+}
+
+#endif /* not _WAKEUP */
+
+static __videocard video_vesa =
+{
+	.card_name	= "VESA",
+	.probe		= vesa_probe,
+	.set_mode	= vesa_set_mode,
+	.xmode_first	= VIDEO_FIRST_VESA,
+	.xmode_n	= 0x200,
+};