src/northbridge/intel/sandybridge/gma_sandybridge_lvds.c - mirrors/cros/chromiumos/third_party/coreboot - Git at Google

 /*
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2013, 2014 Vladimir Serbinenko
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2 or (at your option)
  *  any later version of the License.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc.
  */

 #include <arch/io.h>
 #include <console/console.h>
 #include <delay.h>
 #include <device/device.h>
 #include <string.h>

 #include <drivers/intel/gma/edid.h>
 #include <drivers/intel/gma/i915.h>
 #include "gma.h"
 #include "chip.h"
 #include <pc80/vga.h>
 #include <pc80/vga_io.h>
 #include <device/pci_def.h>
 #include <device/pci_rom.h>

 #if IS_ENABLED(CONFIG_MAINBOARD_DO_NATIVE_VGA_INIT)

 static void train_link(u8 *mmio)
 {
 	/* Clear interrupts. */
 	write32(mmio + DEIIR, 0xffffffff);

 	write32(mmio + 0xf000c, 0x2040);
 	write32(mmio + 0xf000c, 0x2050);
 	write32(mmio + 0x60100, 0x44000);
 	write32(mmio + 0xf000c, 0x22050);

 	mdelay(1);

 	write32(mmio + 0x000f0018, 0x0000008ff);
 	write32(mmio + 0x000f1018, 0x0000008ff);

 	write32(mmio + 0x000f000c, 0x001a2050);
 	write32(mmio + 0x00060100, 0x001c4000);

 	write32(mmio + 0x00060100, 0x801c4000);
 	write32(mmio + 0x000f000c, 0x801a2050);

 	write32(mmio + 0x00060100, 0x801c4000);
 	write32(mmio + 0x000f000c, 0x801a2050);
 	mdelay(1);

 	read32(mmio + 0x000f0014); // = 0x00000100
 	write32(mmio + 0x000f0014, 0x00000100);
 	write32(mmio + 0x00060100, 0x901c4000);
 	write32(mmio + 0x000f000c, 0x801a2150);
 	mdelay(1);
 	read32(mmio + 0x000f0014); // = 0x00000600
 }

 static void power_port(u8 *mmio)
 {
 	read32(mmio + 0x000e1100); // = 0x00000000
 	write32(mmio + 0x000e1100, 0x00000000);
 	write32(mmio + 0x000e1100, 0x00010000);
 	read32(mmio + 0x000e1100); // = 0x00010000
 	read32(mmio + 0x000e1100); // = 0x00010000
 	read32(mmio + 0x000e1100); // = 0x00000000
 	write32(mmio + 0x000e1100, 0x00000000);
 	read32(mmio + 0x000e1100); // = 0x00000000
 	read32(mmio + 0x000e4200); // = 0x0000001c
 	write32(mmio + 0x000e4210, 0x8004003e);
 	write32(mmio + 0x000e4214, 0x80060002);
 	write32(mmio + 0x000e4218, 0x01000000);
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	write32(mmio + 0x000e4210, 0x5344003e);
 	read32(mmio + 0x000e4210); // = 0x0144003e
 	write32(mmio + 0x000e4210, 0x8074003e);
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	write32(mmio + 0x000e4210, 0x5344003e);
 	read32(mmio + 0x000e4210); // = 0x0144003e
 	write32(mmio + 0x000e4210, 0x8074003e);
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	write32(mmio + 0x000e4210, 0x5344003e);
 	read32(mmio + 0x000e4210); // = 0x0144003e
 	write32(mmio + 0x000e4210, 0x8074003e);
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	read32(mmio + 0x000e4210); // = 0x5144003e
 	write32(mmio + 0x000e4210, 0x5344003e);
 	write32(mmio + 0x000e4f00, 0x0100030c);
 	write32(mmio + 0x000e4f04, 0x00b8230c);
 	write32(mmio + 0x000e4f08, 0x06f8930c);
 	write32(mmio + 0x000e4f0c, 0x09f8e38e);
 	write32(mmio + 0x000e4f10, 0x00b8030c);
 	write32(mmio + 0x000e4f14, 0x0b78830c);
 	write32(mmio + 0x000e4f18, 0x0ff8d3cf);
 	write32(mmio + 0x000e4f1c, 0x01e8030c);
 	write32(mmio + 0x000e4f20, 0x0ff863cf);
 	write32(mmio + 0x000e4f24, 0x0ff803cf);
 	write32(mmio + 0x000c4030, 0x00001000);
 	read32(mmio + 0x000c4000); // = 0x00000000
 	write32(mmio + 0x000c4030, 0x00001000);
 	read32(mmio + 0x000e1150); // = 0x0000001c
 	write32(mmio + 0x000e1150, 0x0000089c);
 	write32(mmio + 0x000fcc00, 0x01986f00);
 	write32(mmio + 0x000fcc0c, 0x01986f00);
 	write32(mmio + 0x000fcc18, 0x01986f00);
 	write32(mmio + 0x000fcc24, 0x01986f00);
 	read32(mmio + 0x000c4000); // = 0x00000000
 	read32(mmio + 0x000e1180); // = 0x40000002
 }

 int i915lightup_sandy(const struct i915_gpu_controller_info *info,
 		u32 physbase, u16 piobase, u8 *mmio, u32 lfb)
 {
 	int i;
 	u8 edid_data[128];
 	struct edid edid;
 	u32 hactive, vactive, right_border, bottom_border;
 	int hpolarity, vpolarity;
 	u32 vsync, hsync, vblank, hblank, hfront_porch, vfront_porch;
 	u32 candp1, candn;
 	u32 best_delta = 0xffffffff;
 	u32 target_frequency;
 	u32 pixel_p1 = 1;
 	u32 pixel_n = 1;
 	u32 pixel_m1 = 1;
 	u32 pixel_m2 = 1;
 	u32 link_frequency = info->link_frequency_270_mhz ? 270000 : 162000;
 	u32 data_m1;
 	u32 data_n1 = 0x00800000;
 	u32 link_m1;
 	u32 link_n1 = 0x00080000;

 	write32(mmio + 0x00070080, 0x00000000);
 	write32(mmio + DSPCNTR(0), 0x00000000);
 	write32(mmio + 0x00071180, 0x00000000);
 	write32(mmio + CPU_VGACNTRL, 0x0000298e | VGA_DISP_DISABLE);
 	write32(mmio + 0x0007019c, 0x00000000);
 	write32(mmio + 0x0007119c, 0x00000000);
 	write32(mmio + 0x000ec008, 0x2c010000);
 	write32(mmio + 0x000ec020, 0x2c010000);
 	write32(mmio + 0x000ec038, 0x2c010000);
 	write32(mmio + 0x000ec050, 0x2c010000);
 	write32(mmio + 0x000ec408, 0x2c010000);
 	write32(mmio + 0x000ec420, 0x2c010000);
 	write32(mmio + 0x000ec438, 0x2c010000);
 	write32(mmio + 0x000ec450, 0x2c010000);
 	vga_gr_write(0x18, 0);
 	write32(mmio + 0x00042004, 0x02000000);
 	write32(mmio + 0x000fd034, 0x8421ffe0);

 	/* Setup GTT.  */
 	for (i = 0; i < 0x2000; i++)
 	{
 		outl((i << 2) | 1, piobase);
 		outl(physbase + (i << 12) + 1, piobase + 4);
 	}

 	vga_misc_write(0x67);

 	const u8 cr[] = { 0x5f, 0x4f, 0x50, 0x82, 0x55, 0x81, 0xbf, 0x1f,
 		    0x00, 0x4f, 0x0d, 0x0e, 0x00, 0x00, 0x00, 0x00,
 		    0x9c, 0x8e, 0x8f, 0x28, 0x1f, 0x96, 0xb9, 0xa3,
 		    0xff
 	};
 	vga_cr_write(0x11, 0);

 	for (i = 0; i <= 0x18; i++)
 		vga_cr_write(i, cr[i]);

 	power_port(mmio);

 	intel_gmbus_read_edid(mmio + PCH_GMBUS0, 3, 0x50, edid_data, 128);
 	decode_edid(edid_data,
 		    sizeof(edid_data), &edid);

 	/* Disable screen memory to prevent garbage from appearing.  */
 	vga_sr_write(1, vga_sr_read(1) | 0x20);

 	hactive = edid.x_resolution;
 	vactive = edid.y_resolution;
 	right_border = edid.hborder;
 	bottom_border = edid.vborder;
 	hpolarity = (edid.phsync == '-');
 	vpolarity = (edid.pvsync == '-');
 	vsync = edid.vspw;
 	hsync = edid.hspw;
 	vblank = edid.vbl;
 	hblank = edid.hbl;
 	hfront_porch = edid.hso;
 	vfront_porch = edid.vso;

 	target_frequency = info->lvds_dual_channel ? edid.pixel_clock
 		: (2 * edid.pixel_clock);
 #if !IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
 	vga_textmode_init();
 #else
 	vga_sr_write(1, 1);
 	vga_sr_write(0x2, 0xf);
 	vga_sr_write(0x3, 0x0);
 	vga_sr_write(0x4, 0xe);
 	vga_gr_write(0, 0x0);
 	vga_gr_write(1, 0x0);
 	vga_gr_write(2, 0x0);
 	vga_gr_write(3, 0x0);
 	vga_gr_write(4, 0x0);
 	vga_gr_write(5, 0x0);
 	vga_gr_write(6, 0x5);
 	vga_gr_write(7, 0xf);
 	vga_gr_write(0x10, 0x1);
 	vga_gr_write(0x11, 0);


 	edid.bytes_per_line = (edid.bytes_per_line + 63) & ~63;

 	write32(mmio + DSPCNTR(0), DISPPLANE_BGRX888);
 	write32(mmio + DSPADDR(0), 0);
 	write32(mmio + DSPSTRIDE(0), edid.bytes_per_line);
 	write32(mmio + DSPSURF(0), 0);
 	for (i = 0; i < 0x100; i++)
 		write32(mmio + LGC_PALETTE(0) + 4 * i, i * 0x010101);
 #endif

 	/* Find suitable divisors.  */
 	for (candp1 = 1; candp1 <= 8; candp1++) {
 		for (candn = 5; candn <= 10; candn++) {
 			u32 cur_frequency;
 			u32 m; /* 77 - 131.  */
 			u32 denom; /* 35 - 560.  */
 			u32 current_delta;

 			denom = candn * candp1 * 7;
 			/* Doesnt overflow for up to
 			   5000000 kHz = 5 GHz.  */
 			m = (target_frequency * denom + 60000) / 120000;

 			if (m < 77 || m > 131)
 				continue;

 			cur_frequency = (120000 * m) / denom;
 			if (target_frequency > cur_frequency)
 				current_delta = target_frequency - cur_frequency;
 			else
 				current_delta = cur_frequency - target_frequency;


 			if (best_delta > current_delta) {
 				best_delta = current_delta;
 				pixel_n = candn;
 				pixel_p1 = candp1;
 				pixel_m2 = ((m + 3) % 5) + 7;
 				pixel_m1 = (m - pixel_m2) / 5;
 			}
 		}
 	}

 	if (best_delta == 0xffffffff) {
 		printk (BIOS_ERR, "Couldn't find GFX clock divisors\n");
 		return 0;
 	}

 	link_m1 = ((uint64_t)link_n1 * edid.pixel_clock) / link_frequency;
 	data_m1 = ((uint64_t)data_n1 * 18 * edid.pixel_clock)
 		/ (link_frequency * 8 * (info->lvds_num_lanes ? : 4));

 	printk(BIOS_INFO, "bringing up panel at resolution %d x %d\n",
 	       hactive, vactive);
 	printk(BIOS_DEBUG, "Borders %d x %d\n",
 	       right_border, bottom_border);
 	printk(BIOS_DEBUG, "Blank %d x %d\n",
 	       hblank, vblank);
 	printk(BIOS_DEBUG, "Sync %d x %d\n",
 	       hsync, vsync);
 	printk(BIOS_DEBUG, "Front porch %d x %d\n",
 	       hfront_porch, vfront_porch);
 	printk(BIOS_DEBUG, (info->use_spread_spectrum_clock
 			    ? "Spread spectrum clock\n" : "DREF clock\n"));
 	printk(BIOS_DEBUG,
 	       info->lvds_dual_channel ? "Dual channel\n" : "Single channel\n");
 	printk(BIOS_DEBUG, "Polarities %d, %d\n",
 	       hpolarity, vpolarity);
 	printk(BIOS_DEBUG, "Data M1=%d, N1=%d\n",
 	       data_m1, data_n1);
 	printk(BIOS_DEBUG, "Link frequency %d kHz\n",
 	       link_frequency);
 	printk(BIOS_DEBUG, "Link M1=%d, N1=%d\n",
 	       link_m1, link_n1);
 	printk(BIOS_DEBUG, "Pixel N=%d, M1=%d, M2=%d, P1=%d\n",
 	       pixel_n, pixel_m1, pixel_m2, pixel_p1);
 	printk(BIOS_DEBUG, "Pixel clock %d kHz\n",
 	       120000 * (5 * pixel_m1 + pixel_m2) / pixel_n
 	       / (pixel_p1 * 7));

 	write32(mmio + PCH_LVDS,
 		(hpolarity << 20) | (vpolarity << 21)
 		| (info->lvds_dual_channel ? LVDS_CLOCK_B_POWERUP_ALL
 		   | LVDS_CLOCK_BOTH_POWERUP_ALL : 0)
 		| LVDS_BORDER_ENABLE | LVDS_CLOCK_A_POWERUP_ALL
 		| LVDS_DETECTED);
 	write32(mmio + BLC_PWM_CPU_CTL2, (1 << 31));
 	write32(mmio + PCH_DREF_CONTROL, (info->use_spread_spectrum_clock
 					  ? 0x1002 : 0x400));
 	mdelay(1);
 	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS
 		| (read32(mmio + PCH_PP_CONTROL) & ~PANEL_UNLOCK_MASK));
 	write32(mmio + _PCH_FP0(0),
 		((pixel_n - 2) << 16)
 		| ((pixel_m1 - 2) << 8) | pixel_m2);
 	write32(mmio + PCH_DPLL_SEL, 8);
 	write32(mmio + _PCH_DPLL(0),
 		DPLL_VCO_ENABLE | DPLLB_MODE_LVDS
 		| (info->lvds_dual_channel ? DPLLB_LVDS_P2_CLOCK_DIV_7
 		   : DPLLB_LVDS_P2_CLOCK_DIV_14)
 		| (0x10000 << (pixel_p1 - 1))
 		| ((info->use_spread_spectrum_clock ? 3 : 0) << 13)
 		| (0x1 << (pixel_p1 - 1)));
 	mdelay(1);
 	write32(mmio + _PCH_DPLL(0),
 		DPLL_VCO_ENABLE | DPLLB_MODE_LVDS
 		| (info->lvds_dual_channel ? DPLLB_LVDS_P2_CLOCK_DIV_7
 		   : DPLLB_LVDS_P2_CLOCK_DIV_14)
 		| (0x10000 << (pixel_p1 - 1))
 		| ((info->use_spread_spectrum_clock ? 3 : 0) << 13)
 		| (0x1 << (pixel_p1 - 1)));
 	/* Re-lock the registers.  */
 	write32(mmio + PCH_PP_CONTROL,
 		(read32(mmio + PCH_PP_CONTROL) & ~PANEL_UNLOCK_MASK));

 	write32(mmio + PCH_LVDS,
 		(hpolarity << 20) | (vpolarity << 21)
 		| (info->lvds_dual_channel ? LVDS_CLOCK_B_POWERUP_ALL
 		   | LVDS_CLOCK_BOTH_POWERUP_ALL : 0)
 		| LVDS_BORDER_ENABLE | LVDS_CLOCK_A_POWERUP_ALL
 		| LVDS_DETECTED);

 	write32(mmio + HTOTAL(0),
 		((hactive + right_border + hblank - 1) << 16)
 		| (hactive - 1));
 	write32(mmio + HBLANK(0),
 		((hactive + right_border + hblank - 1) << 16)
 		| (hactive + right_border - 1));
 	write32(mmio + HSYNC(0),
 		((hactive + right_border + hfront_porch + hsync - 1) << 16)
 		| (hactive + right_border + hfront_porch - 1));

 	write32(mmio + VTOTAL(0), ((vactive + bottom_border + vblank - 1) << 16)
 		| (vactive - 1));
 	write32(mmio + VBLANK(0), ((vactive + bottom_border + vblank - 1) << 16)
 		| (vactive + bottom_border - 1));
 	write32(mmio + VSYNC(0),
 		(vactive + bottom_border + vfront_porch + vsync - 1)
 		| (vactive + bottom_border + vfront_porch - 1));

 	write32(mmio + PIPECONF(0), PIPECONF_DISABLE);

 	write32(mmio + PF_WIN_POS(0), 0);
 #if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
 	write32(mmio + PIPESRC(0), ((hactive - 1) << 16) | (vactive - 1));
 	write32(mmio + PF_CTL(0),0);
 	write32(mmio + PF_WIN_SZ(0), 0);
 #else
 	write32(mmio + PIPESRC(0), (639 << 16) | 399);
 	write32(mmio + PF_CTL(0),PF_ENABLE | PF_FILTER_MED_3x3);
 	write32(mmio + PF_WIN_SZ(0), vactive | (hactive << 16));
 #endif

 	mdelay(1);

 	write32(mmio + PIPE_DATA_M1(0), 0x7e000000 | data_m1);
 	write32(mmio + PIPE_DATA_N1(0), data_n1);
 	write32(mmio + PIPE_LINK_M1(0), link_m1);
 	write32(mmio + PIPE_LINK_N1(0), link_n1);

 	write32(mmio + 0x000f000c, 0x00002040);
 	mdelay(1);
 	write32(mmio + 0x000f000c, 0x00002050);
 	write32(mmio + 0x00060100, 0x00044000);
 	mdelay(1);
 	write32(mmio + PIPECONF(0), PIPECONF_BPP_6);
 	write32(mmio + 0x000f000c, 0x00022050);
 	write32(mmio + PIPECONF(0), PIPECONF_BPP_6 | PIPECONF_DITHER_EN);
 	write32(mmio + PIPECONF(0), PIPECONF_ENABLE | PIPECONF_BPP_6 | PIPECONF_DITHER_EN);

 #if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
 	write32(mmio + CPU_VGACNTRL, 0x20298e | VGA_DISP_DISABLE);
 #else
 	write32(mmio + CPU_VGACNTRL, 0x20298e);
 #endif
 	train_link(mmio);

 #if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
 	write32(mmio + DSPCNTR(0), DISPLAY_PLANE_ENABLE | DISPPLANE_BGRX888);
 	mdelay(1);
 #endif

 	write32(mmio + TRANS_HTOTAL(0),
 		((hactive + right_border + hblank - 1) << 16)
 		| (hactive - 1));
 	write32(mmio + TRANS_HBLANK(0),
 		((hactive + right_border + hblank - 1) << 16)
 		| (hactive + right_border - 1));
 	write32(mmio + TRANS_HSYNC(0),
 		((hactive + right_border + hfront_porch + hsync - 1) << 16)
 		| (hactive + right_border + hfront_porch - 1));

 	write32(mmio + TRANS_VTOTAL(0),
 		((vactive + bottom_border + vblank - 1) << 16)
 		| (vactive - 1));
 	write32(mmio + TRANS_VBLANK(0),
 		((vactive + bottom_border + vblank - 1) << 16)
 		| (vactive + bottom_border - 1));
 	write32(mmio + TRANS_VSYNC(0),
 		(vactive + bottom_border + vfront_porch + vsync - 1)
 		| (vactive + bottom_border + vfront_porch - 1));

 	write32(mmio + 0x00060100, 0xb01c4000);
 	write32(mmio + 0x000f000c, 0x801a2350);
 	mdelay(1);
 	write32(mmio + TRANSCONF(0), TRANS_ENABLE | TRANS_6BPC
 #if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
 		| TRANS_STATE_MASK
 #endif
 		);

 	write32(mmio + PCH_LVDS,
 		LVDS_PORT_ENABLE
 		| (hpolarity << 20) | (vpolarity << 21)
 		| (info->lvds_dual_channel ? LVDS_CLOCK_B_POWERUP_ALL
 		   | LVDS_CLOCK_BOTH_POWERUP_ALL : 0)
 		| LVDS_BORDER_ENABLE | LVDS_CLOCK_A_POWERUP_ALL
 		| LVDS_DETECTED);

 	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS | PANEL_POWER_OFF);
 	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS | PANEL_POWER_RESET);
 	mdelay(1);
 	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS
 		| PANEL_POWER_ON | PANEL_POWER_RESET);

 	printk (BIOS_DEBUG, "waiting for panel powerup\n");
 	while (1) {
 		u32 reg32;
 		reg32 = read32(mmio + PCH_PP_STATUS);
 		if (((reg32 >> 28) & 3) == 0)
 			break;
 	}
 	printk (BIOS_DEBUG, "panel powered up\n");

 	write32(mmio + PCH_PP_CONTROL, PANEL_POWER_ON | PANEL_POWER_RESET);

 	/* Enable screen memory.  */
 	vga_sr_write(1, vga_sr_read(1) & ~0x20);

 	/* Clear interrupts. */
 	write32(mmio + DEIIR, 0xffffffff);
 	write32(mmio + SDEIIR, 0xffffffff);

 #if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
 	memset ((void *) lfb, 0, edid.x_resolution * edid.y_resolution * 4);
 	set_vbe_mode_info_valid(&edid, lfb);
 #endif

 	/* Linux relies on VBT for panel info.  */
 	generate_fake_intel_oprom(info, dev_find_slot(0, PCI_DEVFN(2, 0)),
 				  "$VBT SNB/IVB-MOBILE ");

 	return 1;
 }

 #endif
	/*
	* This file is part of the coreboot project.
	*
	* Copyright (C) 2013, 2014 Vladimir Serbinenko
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; version 2 or (at your option)
	* any later version of the License.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc.
	*/

	#include <arch/io.h>
	#include <console/console.h>
	#include <delay.h>
	#include <device/device.h>
	#include <string.h>

	#include <drivers/intel/gma/edid.h>
	#include <drivers/intel/gma/i915.h>
	#include "gma.h"
	#include "chip.h"
	#include <pc80/vga.h>
	#include <pc80/vga_io.h>
	#include <device/pci_def.h>
	#include <device/pci_rom.h>

	#if IS_ENABLED(CONFIG_MAINBOARD_DO_NATIVE_VGA_INIT)

	static void train_link(u8 *mmio)
	{
	/* Clear interrupts. */
	write32(mmio + DEIIR, 0xffffffff);

	write32(mmio + 0xf000c, 0x2040);
	write32(mmio + 0xf000c, 0x2050);
	write32(mmio + 0x60100, 0x44000);
	write32(mmio + 0xf000c, 0x22050);

	mdelay(1);

	write32(mmio + 0x000f0018, 0x0000008ff);
	write32(mmio + 0x000f1018, 0x0000008ff);

	write32(mmio + 0x000f000c, 0x001a2050);
	write32(mmio + 0x00060100, 0x001c4000);

	write32(mmio + 0x00060100, 0x801c4000);
	write32(mmio + 0x000f000c, 0x801a2050);

	write32(mmio + 0x00060100, 0x801c4000);
	write32(mmio + 0x000f000c, 0x801a2050);
	mdelay(1);

	read32(mmio + 0x000f0014); // = 0x00000100
	write32(mmio + 0x000f0014, 0x00000100);
	write32(mmio + 0x00060100, 0x901c4000);
	write32(mmio + 0x000f000c, 0x801a2150);
	mdelay(1);
	read32(mmio + 0x000f0014); // = 0x00000600
	}

	static void power_port(u8 *mmio)
	{
	read32(mmio + 0x000e1100); // = 0x00000000
	write32(mmio + 0x000e1100, 0x00000000);
	write32(mmio + 0x000e1100, 0x00010000);
	read32(mmio + 0x000e1100); // = 0x00010000
	read32(mmio + 0x000e1100); // = 0x00010000
	read32(mmio + 0x000e1100); // = 0x00000000
	write32(mmio + 0x000e1100, 0x00000000);
	read32(mmio + 0x000e1100); // = 0x00000000
	read32(mmio + 0x000e4200); // = 0x0000001c
	write32(mmio + 0x000e4210, 0x8004003e);
	write32(mmio + 0x000e4214, 0x80060002);
	write32(mmio + 0x000e4218, 0x01000000);
	read32(mmio + 0x000e4210); // = 0x5144003e
	write32(mmio + 0x000e4210, 0x5344003e);
	read32(mmio + 0x000e4210); // = 0x0144003e
	write32(mmio + 0x000e4210, 0x8074003e);
	read32(mmio + 0x000e4210); // = 0x5144003e
	read32(mmio + 0x000e4210); // = 0x5144003e
	write32(mmio + 0x000e4210, 0x5344003e);
	read32(mmio + 0x000e4210); // = 0x0144003e
	write32(mmio + 0x000e4210, 0x8074003e);
	read32(mmio + 0x000e4210); // = 0x5144003e
	read32(mmio + 0x000e4210); // = 0x5144003e
	write32(mmio + 0x000e4210, 0x5344003e);
	read32(mmio + 0x000e4210); // = 0x0144003e
	write32(mmio + 0x000e4210, 0x8074003e);
	read32(mmio + 0x000e4210); // = 0x5144003e
	read32(mmio + 0x000e4210); // = 0x5144003e
	write32(mmio + 0x000e4210, 0x5344003e);
	write32(mmio + 0x000e4f00, 0x0100030c);
	write32(mmio + 0x000e4f04, 0x00b8230c);
	write32(mmio + 0x000e4f08, 0x06f8930c);
	write32(mmio + 0x000e4f0c, 0x09f8e38e);
	write32(mmio + 0x000e4f10, 0x00b8030c);
	write32(mmio + 0x000e4f14, 0x0b78830c);
	write32(mmio + 0x000e4f18, 0x0ff8d3cf);
	write32(mmio + 0x000e4f1c, 0x01e8030c);
	write32(mmio + 0x000e4f20, 0x0ff863cf);
	write32(mmio + 0x000e4f24, 0x0ff803cf);
	write32(mmio + 0x000c4030, 0x00001000);
	read32(mmio + 0x000c4000); // = 0x00000000
	write32(mmio + 0x000c4030, 0x00001000);
	read32(mmio + 0x000e1150); // = 0x0000001c
	write32(mmio + 0x000e1150, 0x0000089c);
	write32(mmio + 0x000fcc00, 0x01986f00);
	write32(mmio + 0x000fcc0c, 0x01986f00);
	write32(mmio + 0x000fcc18, 0x01986f00);
	write32(mmio + 0x000fcc24, 0x01986f00);
	read32(mmio + 0x000c4000); // = 0x00000000
	read32(mmio + 0x000e1180); // = 0x40000002
	}

	int i915lightup_sandy(const struct i915_gpu_controller_info *info,
	u32 physbase, u16 piobase, u8 *mmio, u32 lfb)
	{
	int i;
	u8 edid_data[128];
	struct edid edid;
	u32 hactive, vactive, right_border, bottom_border;
	int hpolarity, vpolarity;
	u32 vsync, hsync, vblank, hblank, hfront_porch, vfront_porch;
	u32 candp1, candn;
	u32 best_delta = 0xffffffff;
	u32 target_frequency;
	u32 pixel_p1 = 1;
	u32 pixel_n = 1;
	u32 pixel_m1 = 1;
	u32 pixel_m2 = 1;
	u32 link_frequency = info->link_frequency_270_mhz ? 270000 : 162000;
	u32 data_m1;
	u32 data_n1 = 0x00800000;
	u32 link_m1;
	u32 link_n1 = 0x00080000;

	write32(mmio + 0x00070080, 0x00000000);
	write32(mmio + DSPCNTR(0), 0x00000000);
	write32(mmio + 0x00071180, 0x00000000);
	write32(mmio + CPU_VGACNTRL, 0x0000298e \| VGA_DISP_DISABLE);
	write32(mmio + 0x0007019c, 0x00000000);
	write32(mmio + 0x0007119c, 0x00000000);
	write32(mmio + 0x000ec008, 0x2c010000);
	write32(mmio + 0x000ec020, 0x2c010000);
	write32(mmio + 0x000ec038, 0x2c010000);
	write32(mmio + 0x000ec050, 0x2c010000);
	write32(mmio + 0x000ec408, 0x2c010000);
	write32(mmio + 0x000ec420, 0x2c010000);
	write32(mmio + 0x000ec438, 0x2c010000);
	write32(mmio + 0x000ec450, 0x2c010000);
	vga_gr_write(0x18, 0);
	write32(mmio + 0x00042004, 0x02000000);
	write32(mmio + 0x000fd034, 0x8421ffe0);

	/* Setup GTT. */
	for (i = 0; i < 0x2000; i++)
	{
	outl((i << 2) \| 1, piobase);
	outl(physbase + (i << 12) + 1, piobase + 4);
	}

	vga_misc_write(0x67);

	const u8 cr[] = { 0x5f, 0x4f, 0x50, 0x82, 0x55, 0x81, 0xbf, 0x1f,
	0x00, 0x4f, 0x0d, 0x0e, 0x00, 0x00, 0x00, 0x00,
	0x9c, 0x8e, 0x8f, 0x28, 0x1f, 0x96, 0xb9, 0xa3,
	0xff
	};
	vga_cr_write(0x11, 0);

	for (i = 0; i <= 0x18; i++)
	vga_cr_write(i, cr[i]);

	power_port(mmio);

	intel_gmbus_read_edid(mmio + PCH_GMBUS0, 3, 0x50, edid_data, 128);
	decode_edid(edid_data,
	sizeof(edid_data), &edid);

	/* Disable screen memory to prevent garbage from appearing. */
	vga_sr_write(1, vga_sr_read(1) \| 0x20);

	hactive = edid.x_resolution;
	vactive = edid.y_resolution;
	right_border = edid.hborder;
	bottom_border = edid.vborder;
	hpolarity = (edid.phsync == '-');
	vpolarity = (edid.pvsync == '-');
	vsync = edid.vspw;
	hsync = edid.hspw;
	vblank = edid.vbl;
	hblank = edid.hbl;
	hfront_porch = edid.hso;
	vfront_porch = edid.vso;

	target_frequency = info->lvds_dual_channel ? edid.pixel_clock
	: (2 * edid.pixel_clock);
	#if !IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
	vga_textmode_init();
	#else
	vga_sr_write(1, 1);
	vga_sr_write(0x2, 0xf);
	vga_sr_write(0x3, 0x0);
	vga_sr_write(0x4, 0xe);
	vga_gr_write(0, 0x0);
	vga_gr_write(1, 0x0);
	vga_gr_write(2, 0x0);
	vga_gr_write(3, 0x0);
	vga_gr_write(4, 0x0);
	vga_gr_write(5, 0x0);
	vga_gr_write(6, 0x5);
	vga_gr_write(7, 0xf);
	vga_gr_write(0x10, 0x1);
	vga_gr_write(0x11, 0);


	edid.bytes_per_line = (edid.bytes_per_line + 63) & ~63;

	write32(mmio + DSPCNTR(0), DISPPLANE_BGRX888);
	write32(mmio + DSPADDR(0), 0);
	write32(mmio + DSPSTRIDE(0), edid.bytes_per_line);
	write32(mmio + DSPSURF(0), 0);
	for (i = 0; i < 0x100; i++)
	write32(mmio + LGC_PALETTE(0) + 4 * i, i * 0x010101);
	#endif

	/* Find suitable divisors. */
	for (candp1 = 1; candp1 <= 8; candp1++) {
	for (candn = 5; candn <= 10; candn++) {
	u32 cur_frequency;
	u32 m; /* 77 - 131. */
	u32 denom; /* 35 - 560. */
	u32 current_delta;

	denom = candn * candp1 * 7;
	/* Doesnt overflow for up to
	5000000 kHz = 5 GHz. */
	m = (target_frequency * denom + 60000) / 120000;

	if (m < 77 \|\| m > 131)
	continue;

	cur_frequency = (120000 * m) / denom;
	if (target_frequency > cur_frequency)
	current_delta = target_frequency - cur_frequency;
	else
	current_delta = cur_frequency - target_frequency;


	if (best_delta > current_delta) {
	best_delta = current_delta;
	pixel_n = candn;
	pixel_p1 = candp1;
	pixel_m2 = ((m + 3) % 5) + 7;
	pixel_m1 = (m - pixel_m2) / 5;
	}
	}
	}

	if (best_delta == 0xffffffff) {
	printk (BIOS_ERR, "Couldn't find GFX clock divisors\n");
	return 0;
	}

	link_m1 = ((uint64_t)link_n1 * edid.pixel_clock) / link_frequency;
	data_m1 = ((uint64_t)data_n1 * 18 * edid.pixel_clock)
	/ (link_frequency * 8 * (info->lvds_num_lanes ? : 4));

	printk(BIOS_INFO, "bringing up panel at resolution %d x %d\n",
	hactive, vactive);
	printk(BIOS_DEBUG, "Borders %d x %d\n",
	right_border, bottom_border);
	printk(BIOS_DEBUG, "Blank %d x %d\n",
	hblank, vblank);
	printk(BIOS_DEBUG, "Sync %d x %d\n",
	hsync, vsync);
	printk(BIOS_DEBUG, "Front porch %d x %d\n",
	hfront_porch, vfront_porch);
	printk(BIOS_DEBUG, (info->use_spread_spectrum_clock
	? "Spread spectrum clock\n" : "DREF clock\n"));
	printk(BIOS_DEBUG,
	info->lvds_dual_channel ? "Dual channel\n" : "Single channel\n");
	printk(BIOS_DEBUG, "Polarities %d, %d\n",
	hpolarity, vpolarity);
	printk(BIOS_DEBUG, "Data M1=%d, N1=%d\n",
	data_m1, data_n1);
	printk(BIOS_DEBUG, "Link frequency %d kHz\n",
	link_frequency);
	printk(BIOS_DEBUG, "Link M1=%d, N1=%d\n",
	link_m1, link_n1);
	printk(BIOS_DEBUG, "Pixel N=%d, M1=%d, M2=%d, P1=%d\n",
	pixel_n, pixel_m1, pixel_m2, pixel_p1);
	printk(BIOS_DEBUG, "Pixel clock %d kHz\n",
	120000 * (5 * pixel_m1 + pixel_m2) / pixel_n
	/ (pixel_p1 * 7));

	write32(mmio + PCH_LVDS,
	(hpolarity << 20) \| (vpolarity << 21)
	\| (info->lvds_dual_channel ? LVDS_CLOCK_B_POWERUP_ALL
	\| LVDS_CLOCK_BOTH_POWERUP_ALL : 0)
	\| LVDS_BORDER_ENABLE \| LVDS_CLOCK_A_POWERUP_ALL
	\| LVDS_DETECTED);
	write32(mmio + BLC_PWM_CPU_CTL2, (1 << 31));
	write32(mmio + PCH_DREF_CONTROL, (info->use_spread_spectrum_clock
	? 0x1002 : 0x400));
	mdelay(1);
	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS
	\| (read32(mmio + PCH_PP_CONTROL) & ~PANEL_UNLOCK_MASK));
	write32(mmio + _PCH_FP0(0),
	((pixel_n - 2) << 16)
	\| ((pixel_m1 - 2) << 8) \| pixel_m2);
	write32(mmio + PCH_DPLL_SEL, 8);
	write32(mmio + _PCH_DPLL(0),
	DPLL_VCO_ENABLE \| DPLLB_MODE_LVDS
	\| (info->lvds_dual_channel ? DPLLB_LVDS_P2_CLOCK_DIV_7
	: DPLLB_LVDS_P2_CLOCK_DIV_14)
	\| (0x10000 << (pixel_p1 - 1))
	\| ((info->use_spread_spectrum_clock ? 3 : 0) << 13)
	\| (0x1 << (pixel_p1 - 1)));
	mdelay(1);
	write32(mmio + _PCH_DPLL(0),
	DPLL_VCO_ENABLE \| DPLLB_MODE_LVDS
	\| (info->lvds_dual_channel ? DPLLB_LVDS_P2_CLOCK_DIV_7
	: DPLLB_LVDS_P2_CLOCK_DIV_14)
	\| (0x10000 << (pixel_p1 - 1))
	\| ((info->use_spread_spectrum_clock ? 3 : 0) << 13)
	\| (0x1 << (pixel_p1 - 1)));
	/* Re-lock the registers. */
	write32(mmio + PCH_PP_CONTROL,
	(read32(mmio + PCH_PP_CONTROL) & ~PANEL_UNLOCK_MASK));

	write32(mmio + PCH_LVDS,
	(hpolarity << 20) \| (vpolarity << 21)
	\| (info->lvds_dual_channel ? LVDS_CLOCK_B_POWERUP_ALL
	\| LVDS_CLOCK_BOTH_POWERUP_ALL : 0)
	\| LVDS_BORDER_ENABLE \| LVDS_CLOCK_A_POWERUP_ALL
	\| LVDS_DETECTED);

	write32(mmio + HTOTAL(0),
	((hactive + right_border + hblank - 1) << 16)
	\| (hactive - 1));
	write32(mmio + HBLANK(0),
	((hactive + right_border + hblank - 1) << 16)
	\| (hactive + right_border - 1));
	write32(mmio + HSYNC(0),
	((hactive + right_border + hfront_porch + hsync - 1) << 16)
	\| (hactive + right_border + hfront_porch - 1));

	write32(mmio + VTOTAL(0), ((vactive + bottom_border + vblank - 1) << 16)
	\| (vactive - 1));
	write32(mmio + VBLANK(0), ((vactive + bottom_border + vblank - 1) << 16)
	\| (vactive + bottom_border - 1));
	write32(mmio + VSYNC(0),
	(vactive + bottom_border + vfront_porch + vsync - 1)
	\| (vactive + bottom_border + vfront_porch - 1));

	write32(mmio + PIPECONF(0), PIPECONF_DISABLE);

	write32(mmio + PF_WIN_POS(0), 0);
	#if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
	write32(mmio + PIPESRC(0), ((hactive - 1) << 16) \| (vactive - 1));
	write32(mmio + PF_CTL(0),0);
	write32(mmio + PF_WIN_SZ(0), 0);
	#else
	write32(mmio + PIPESRC(0), (639 << 16) \| 399);
	write32(mmio + PF_CTL(0),PF_ENABLE \| PF_FILTER_MED_3x3);
	write32(mmio + PF_WIN_SZ(0), vactive \| (hactive << 16));
	#endif

	mdelay(1);

	write32(mmio + PIPE_DATA_M1(0), 0x7e000000 \| data_m1);
	write32(mmio + PIPE_DATA_N1(0), data_n1);
	write32(mmio + PIPE_LINK_M1(0), link_m1);
	write32(mmio + PIPE_LINK_N1(0), link_n1);

	write32(mmio + 0x000f000c, 0x00002040);
	mdelay(1);
	write32(mmio + 0x000f000c, 0x00002050);
	write32(mmio + 0x00060100, 0x00044000);
	mdelay(1);
	write32(mmio + PIPECONF(0), PIPECONF_BPP_6);
	write32(mmio + 0x000f000c, 0x00022050);
	write32(mmio + PIPECONF(0), PIPECONF_BPP_6 \| PIPECONF_DITHER_EN);
	write32(mmio + PIPECONF(0), PIPECONF_ENABLE \| PIPECONF_BPP_6 \| PIPECONF_DITHER_EN);

	#if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
	write32(mmio + CPU_VGACNTRL, 0x20298e \| VGA_DISP_DISABLE);
	#else
	write32(mmio + CPU_VGACNTRL, 0x20298e);
	#endif
	train_link(mmio);

	#if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
	write32(mmio + DSPCNTR(0), DISPLAY_PLANE_ENABLE \| DISPPLANE_BGRX888);
	mdelay(1);
	#endif

	write32(mmio + TRANS_HTOTAL(0),
	((hactive + right_border + hblank - 1) << 16)
	\| (hactive - 1));
	write32(mmio + TRANS_HBLANK(0),
	((hactive + right_border + hblank - 1) << 16)
	\| (hactive + right_border - 1));
	write32(mmio + TRANS_HSYNC(0),
	((hactive + right_border + hfront_porch + hsync - 1) << 16)
	\| (hactive + right_border + hfront_porch - 1));

	write32(mmio + TRANS_VTOTAL(0),
	((vactive + bottom_border + vblank - 1) << 16)
	\| (vactive - 1));
	write32(mmio + TRANS_VBLANK(0),
	((vactive + bottom_border + vblank - 1) << 16)
	\| (vactive + bottom_border - 1));
	write32(mmio + TRANS_VSYNC(0),
	(vactive + bottom_border + vfront_porch + vsync - 1)
	\| (vactive + bottom_border + vfront_porch - 1));

	write32(mmio + 0x00060100, 0xb01c4000);
	write32(mmio + 0x000f000c, 0x801a2350);
	mdelay(1);
	write32(mmio + TRANSCONF(0), TRANS_ENABLE \| TRANS_6BPC
	#if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
	\| TRANS_STATE_MASK
	#endif
	);

	write32(mmio + PCH_LVDS,
	LVDS_PORT_ENABLE
	\| (hpolarity << 20) \| (vpolarity << 21)
	\| (info->lvds_dual_channel ? LVDS_CLOCK_B_POWERUP_ALL
	\| LVDS_CLOCK_BOTH_POWERUP_ALL : 0)
	\| LVDS_BORDER_ENABLE \| LVDS_CLOCK_A_POWERUP_ALL
	\| LVDS_DETECTED);

	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS \| PANEL_POWER_OFF);
	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS \| PANEL_POWER_RESET);
	mdelay(1);
	write32(mmio + PCH_PP_CONTROL, PANEL_UNLOCK_REGS
	\| PANEL_POWER_ON \| PANEL_POWER_RESET);

	printk (BIOS_DEBUG, "waiting for panel powerup\n");
	while (1) {
	u32 reg32;
	reg32 = read32(mmio + PCH_PP_STATUS);
	if (((reg32 >> 28) & 3) == 0)
	break;
	}
	printk (BIOS_DEBUG, "panel powered up\n");

	write32(mmio + PCH_PP_CONTROL, PANEL_POWER_ON \| PANEL_POWER_RESET);

	/* Enable screen memory. */
	vga_sr_write(1, vga_sr_read(1) & ~0x20);

	/* Clear interrupts. */
	write32(mmio + DEIIR, 0xffffffff);
	write32(mmio + SDEIIR, 0xffffffff);

	#if IS_ENABLED(CONFIG_FRAMEBUFFER_KEEP_VESA_MODE)
	memset ((void ) lfb, 0, edid.x_resolution edid.y_resolution * 4);
	set_vbe_mode_info_valid(&edid, lfb);
	#endif

	/* Linux relies on VBT for panel info. */
	generate_fake_intel_oprom(info, dev_find_slot(0, PCI_DEVFN(2, 0)),
	"$VBT SNB/IVB-MOBILE ");

	return 1;
	}

	#endif