drivers/gpu/drm/cirrus/cirrus_mode.c - kernel/msm-4.9 - Gitiles


 /*
  * Copyright 2012 Red Hat
  *
  * This file is subject to the terms and conditions of the GNU General
  * Public License version 2. See the file COPYING in the main
  * directory of this archive for more details.
  *
  * Authors: Matthew Garrett
  *          Dave Airlie
  *
  * Portions of this code derived from cirrusfb.c:
  * drivers/video/cirrusfb.c - driver for Cirrus Logic chipsets
  *
  * Copyright 1999-2001 Jeff Garzik <jgarzik@pobox.com>
  */
 #include <drm/drmP.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_plane_helper.h>

 #include <video/cirrus.h>

 #include "cirrus_drv.h"

 #define CIRRUS_LUT_SIZE 256

 #define PALETTE_INDEX 0x8
 #define PALETTE_DATA 0x9

 /*
  * This file contains setup code for the CRTC.
  */

 static void cirrus_crtc_load_lut(struct drm_crtc *crtc)
 {
 	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct cirrus_device *cdev = dev->dev_private;
 	int i;

 	if (!crtc->enabled)
 		return;

 	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
 		/* VGA registers */
 		WREG8(PALETTE_INDEX, i);
 		WREG8(PALETTE_DATA, cirrus_crtc->lut_r[i]);
 		WREG8(PALETTE_DATA, cirrus_crtc->lut_g[i]);
 		WREG8(PALETTE_DATA, cirrus_crtc->lut_b[i]);
 	}
 }

 /*
  * The DRM core requires DPMS functions, but they make little sense in our
  * case and so are just stubs
  */

 static void cirrus_crtc_dpms(struct drm_crtc *crtc, int mode)
 {
 	struct drm_device *dev = crtc->dev;
 	struct cirrus_device *cdev = dev->dev_private;
 	u8 sr01, gr0e;

 	switch (mode) {
 	case DRM_MODE_DPMS_ON:
 		sr01 = 0x00;
 		gr0e = 0x00;
 		break;
 	case DRM_MODE_DPMS_STANDBY:
 		sr01 = 0x20;
 		gr0e = 0x02;
 		break;
 	case DRM_MODE_DPMS_SUSPEND:
 		sr01 = 0x20;
 		gr0e = 0x04;
 		break;
 	case DRM_MODE_DPMS_OFF:
 		sr01 = 0x20;
 		gr0e = 0x06;
 		break;
 	default:
 		return;
 	}

 	WREG8(SEQ_INDEX, 0x1);
 	sr01 |= RREG8(SEQ_DATA) & ~0x20;
 	WREG_SEQ(0x1, sr01);

 	WREG8(GFX_INDEX, 0xe);
 	gr0e |= RREG8(GFX_DATA) & ~0x06;
 	WREG_GFX(0xe, gr0e);
 }

 /*
  * The core passes the desired mode to the CRTC code to see whether any
  * CRTC-specific modifications need to be made to it. We're in a position
  * to just pass that straight through, so this does nothing
  */
 static bool cirrus_crtc_mode_fixup(struct drm_crtc *crtc,
 				   const struct drm_display_mode *mode,
 				   struct drm_display_mode *adjusted_mode)
 {
 	return true;
 }

 static void cirrus_set_start_address(struct drm_crtc *crtc, unsigned offset)
 {
 	struct cirrus_device *cdev = crtc->dev->dev_private;
 	u32 addr;
 	u8 tmp;

 	addr = offset >> 2;
 	WREG_CRT(0x0c, (u8)((addr >> 8) & 0xff));
 	WREG_CRT(0x0d, (u8)(addr & 0xff));

 	WREG8(CRT_INDEX, 0x1b);
 	tmp = RREG8(CRT_DATA);
 	tmp &= 0xf2;
 	tmp |= (addr >> 16) & 0x01;
 	tmp |= (addr >> 15) & 0x0c;
 	WREG_CRT(0x1b, tmp);
 	WREG8(CRT_INDEX, 0x1d);
 	tmp = RREG8(CRT_DATA);
 	tmp &= 0x7f;
 	tmp |= (addr >> 12) & 0x80;
 	WREG_CRT(0x1d, tmp);
 }

 /* cirrus is different - we will force move buffers out of VRAM */
 static int cirrus_crtc_do_set_base(struct drm_crtc *crtc,
 				struct drm_framebuffer *fb,
 				int x, int y, int atomic)
 {
 	struct cirrus_device *cdev = crtc->dev->dev_private;
 	struct drm_gem_object *obj;
 	struct cirrus_framebuffer *cirrus_fb;
 	struct cirrus_bo *bo;
 	int ret;
 	u64 gpu_addr;

 	/* push the previous fb to system ram */
 	if (!atomic && fb) {
 		cirrus_fb = to_cirrus_framebuffer(fb);
 		obj = cirrus_fb->obj;
 		bo = gem_to_cirrus_bo(obj);
 		ret = cirrus_bo_reserve(bo, false);
 		if (ret)
 			return ret;
 		cirrus_bo_push_sysram(bo);
 		cirrus_bo_unreserve(bo);
 	}

 	cirrus_fb = to_cirrus_framebuffer(crtc->primary->fb);
 	obj = cirrus_fb->obj;
 	bo = gem_to_cirrus_bo(obj);

 	ret = cirrus_bo_reserve(bo, false);
 	if (ret)
 		return ret;

 	ret = cirrus_bo_pin(bo, TTM_PL_FLAG_VRAM, &gpu_addr);
 	if (ret) {
 		cirrus_bo_unreserve(bo);
 		return ret;
 	}

 	if (&cdev->mode_info.gfbdev->gfb == cirrus_fb) {
 		/* if pushing console in kmap it */
 		ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
 		if (ret)
 			DRM_ERROR("failed to kmap fbcon\n");
 	}
 	cirrus_bo_unreserve(bo);

 	cirrus_set_start_address(crtc, (u32)gpu_addr);
 	return 0;
 }

 static int cirrus_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
 			     struct drm_framebuffer *old_fb)
 {
 	return cirrus_crtc_do_set_base(crtc, old_fb, x, y, 0);
 }

 /*
  * The meat of this driver. The core passes us a mode and we have to program
  * it. The modesetting here is the bare minimum required to satisfy the qemu
  * emulation of this hardware, and running this against a real device is
  * likely to result in an inadequately programmed mode. We've already had
  * the opportunity to modify the mode, so whatever we receive here should
  * be something that can be correctly programmed and displayed
  */
 static int cirrus_crtc_mode_set(struct drm_crtc *crtc,
 				struct drm_display_mode *mode,
 				struct drm_display_mode *adjusted_mode,
 				int x, int y, struct drm_framebuffer *old_fb)
 {
 	struct drm_device *dev = crtc->dev;
 	struct cirrus_device *cdev = dev->dev_private;
 	int hsyncstart, hsyncend, htotal, hdispend;
 	int vtotal, vdispend;
 	int tmp;
 	int sr07 = 0, hdr = 0;

 	htotal = mode->htotal / 8;
 	hsyncend = mode->hsync_end / 8;
 	hsyncstart = mode->hsync_start / 8;
 	hdispend = mode->hdisplay / 8;

 	vtotal = mode->vtotal;
 	vdispend = mode->vdisplay;

 	vdispend -= 1;
 	vtotal -= 2;

 	htotal -= 5;
 	hdispend -= 1;
 	hsyncstart += 1;
 	hsyncend += 1;

 	WREG_CRT(VGA_CRTC_V_SYNC_END, 0x20);
 	WREG_CRT(VGA_CRTC_H_TOTAL, htotal);
 	WREG_CRT(VGA_CRTC_H_DISP, hdispend);
 	WREG_CRT(VGA_CRTC_H_SYNC_START, hsyncstart);
 	WREG_CRT(VGA_CRTC_H_SYNC_END, hsyncend);
 	WREG_CRT(VGA_CRTC_V_TOTAL, vtotal & 0xff);
 	WREG_CRT(VGA_CRTC_V_DISP_END, vdispend & 0xff);

 	tmp = 0x40;
 	if ((vdispend + 1) & 512)
 		tmp |= 0x20;
 	WREG_CRT(VGA_CRTC_MAX_SCAN, tmp);

 	/*
 	 * Overflow bits for values that don't fit in the standard registers
 	 */
 	tmp = 16;
 	if (vtotal & 256)
 		tmp |= 1;
 	if (vdispend & 256)
 		tmp |= 2;
 	if ((vdispend + 1) & 256)
 		tmp |= 8;
 	if (vtotal & 512)
 		tmp |= 32;
 	if (vdispend & 512)
 		tmp |= 64;
 	WREG_CRT(VGA_CRTC_OVERFLOW, tmp);

 	tmp = 0;

 	/* More overflow bits */

 	if ((htotal + 5) & 64)
 		tmp |= 16;
 	if ((htotal + 5) & 128)
 		tmp |= 32;
 	if (vtotal & 256)
 		tmp |= 64;
 	if (vtotal & 512)
 		tmp |= 128;

 	WREG_CRT(CL_CRT1A, tmp);

 	/* Disable Hercules/CGA compatibility */
 	WREG_CRT(VGA_CRTC_MODE, 0x03);

 	WREG8(SEQ_INDEX, 0x7);
 	sr07 = RREG8(SEQ_DATA);
 	sr07 &= 0xe0;
 	hdr = 0;
 	switch (crtc->primary->fb->bits_per_pixel) {
 	case 8:
 		sr07 |= 0x11;
 		break;
 	case 16:
 		sr07 |= 0x17;
 		hdr = 0xc1;
 		break;
 	case 24:
 		sr07 |= 0x15;
 		hdr = 0xc5;
 		break;
 	case 32:
 		sr07 |= 0x19;
 		hdr = 0xc5;
 		break;
 	default:
 		return -1;
 	}

 	WREG_SEQ(0x7, sr07);

 	/* Program the pitch */
 	tmp = crtc->primary->fb->pitches[0] / 8;
 	WREG_CRT(VGA_CRTC_OFFSET, tmp);

 	/* Enable extended blanking and pitch bits, and enable full memory */
 	tmp = 0x22;
 	tmp |= (crtc->primary->fb->pitches[0] >> 7) & 0x10;
 	tmp |= (crtc->primary->fb->pitches[0] >> 6) & 0x40;
 	WREG_CRT(0x1b, tmp);

 	/* Enable high-colour modes */
 	WREG_GFX(VGA_GFX_MODE, 0x40);

 	/* And set graphics mode */
 	WREG_GFX(VGA_GFX_MISC, 0x01);

 	WREG_HDR(hdr);
 	cirrus_crtc_do_set_base(crtc, old_fb, x, y, 0);

 	/* Unblank (needed on S3 resume, vgabios doesn't do it then) */
 	outb(0x20, 0x3c0);
 	return 0;
 }

 /*
  * This is called before a mode is programmed. A typical use might be to
  * enable DPMS during the programming to avoid seeing intermediate stages,
  * but that's not relevant to us
  */
 static void cirrus_crtc_prepare(struct drm_crtc *crtc)
 {
 }

 /*
  * This is called after a mode is programmed. It should reverse anything done
  * by the prepare function
  */
 static void cirrus_crtc_commit(struct drm_crtc *crtc)
 {
 }

 /*
  * The core can pass us a set of gamma values to program. We actually only
  * use this for 8-bit mode so can't perform smooth fades on deeper modes,
  * but it's a requirement that we provide the function
  */
 static void cirrus_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				  u16 *blue, uint32_t start, uint32_t size)
 {
 	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
 	int i;

 	if (size != CIRRUS_LUT_SIZE)
 		return;

 	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
 		cirrus_crtc->lut_r[i] = red[i];
 		cirrus_crtc->lut_g[i] = green[i];
 		cirrus_crtc->lut_b[i] = blue[i];
 	}
 	cirrus_crtc_load_lut(crtc);
 }

 /* Simple cleanup function */
 static void cirrus_crtc_destroy(struct drm_crtc *crtc)
 {
 	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);

 	drm_crtc_cleanup(crtc);
 	kfree(cirrus_crtc);
 }

 /* These provide the minimum set of functions required to handle a CRTC */
 static const struct drm_crtc_funcs cirrus_crtc_funcs = {
 	.gamma_set = cirrus_crtc_gamma_set,
 	.set_config = drm_crtc_helper_set_config,
 	.destroy = cirrus_crtc_destroy,
 };

 static const struct drm_crtc_helper_funcs cirrus_helper_funcs = {
 	.dpms = cirrus_crtc_dpms,
 	.mode_fixup = cirrus_crtc_mode_fixup,
 	.mode_set = cirrus_crtc_mode_set,
 	.mode_set_base = cirrus_crtc_mode_set_base,
 	.prepare = cirrus_crtc_prepare,
 	.commit = cirrus_crtc_commit,
 	.load_lut = cirrus_crtc_load_lut,
 };

 /* CRTC setup */
 static void cirrus_crtc_init(struct drm_device *dev)
 {
 	struct cirrus_device *cdev = dev->dev_private;
 	struct cirrus_crtc *cirrus_crtc;
 	int i;

 	cirrus_crtc = kzalloc(sizeof(struct cirrus_crtc) +
 			      (CIRRUSFB_CONN_LIMIT * sizeof(struct drm_connector *)),
 			      GFP_KERNEL);

 	if (cirrus_crtc == NULL)
 		return;

 	drm_crtc_init(dev, &cirrus_crtc->base, &cirrus_crtc_funcs);

 	drm_mode_crtc_set_gamma_size(&cirrus_crtc->base, CIRRUS_LUT_SIZE);
 	cdev->mode_info.crtc = cirrus_crtc;

 	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
 		cirrus_crtc->lut_r[i] = i;
 		cirrus_crtc->lut_g[i] = i;
 		cirrus_crtc->lut_b[i] = i;
 	}

 	drm_crtc_helper_add(&cirrus_crtc->base, &cirrus_helper_funcs);
 }

 /** Sets the color ramps on behalf of fbcon */
 void cirrus_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
 			      u16 blue, int regno)
 {
 	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);

 	cirrus_crtc->lut_r[regno] = red;
 	cirrus_crtc->lut_g[regno] = green;
 	cirrus_crtc->lut_b[regno] = blue;
 }

 /** Gets the color ramps on behalf of fbcon */
 void cirrus_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
 			      u16 *blue, int regno)
 {
 	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);

 	*red = cirrus_crtc->lut_r[regno];
 	*green = cirrus_crtc->lut_g[regno];
 	*blue = cirrus_crtc->lut_b[regno];
 }


 static bool cirrus_encoder_mode_fixup(struct drm_encoder *encoder,
 				      const struct drm_display_mode *mode,
 				      struct drm_display_mode *adjusted_mode)
 {
 	return true;
 }

 static void cirrus_encoder_mode_set(struct drm_encoder *encoder,
 				struct drm_display_mode *mode,
 				struct drm_display_mode *adjusted_mode)
 {
 }

 static void cirrus_encoder_dpms(struct drm_encoder *encoder, int state)
 {
 	return;
 }

 static void cirrus_encoder_prepare(struct drm_encoder *encoder)
 {
 }

 static void cirrus_encoder_commit(struct drm_encoder *encoder)
 {
 }

 static void cirrus_encoder_destroy(struct drm_encoder *encoder)
 {
 	struct cirrus_encoder *cirrus_encoder = to_cirrus_encoder(encoder);
 	drm_encoder_cleanup(encoder);
 	kfree(cirrus_encoder);
 }

 static const struct drm_encoder_helper_funcs cirrus_encoder_helper_funcs = {
 	.dpms = cirrus_encoder_dpms,
 	.mode_fixup = cirrus_encoder_mode_fixup,
 	.mode_set = cirrus_encoder_mode_set,
 	.prepare = cirrus_encoder_prepare,
 	.commit = cirrus_encoder_commit,
 };

 static const struct drm_encoder_funcs cirrus_encoder_encoder_funcs = {
 	.destroy = cirrus_encoder_destroy,
 };

 static struct drm_encoder *cirrus_encoder_init(struct drm_device *dev)
 {
 	struct drm_encoder *encoder;
 	struct cirrus_encoder *cirrus_encoder;

 	cirrus_encoder = kzalloc(sizeof(struct cirrus_encoder), GFP_KERNEL);
 	if (!cirrus_encoder)
 		return NULL;

 	encoder = &cirrus_encoder->base;
 	encoder->possible_crtcs = 0x1;

 	drm_encoder_init(dev, encoder, &cirrus_encoder_encoder_funcs,
 			 DRM_MODE_ENCODER_DAC, NULL);
 	drm_encoder_helper_add(encoder, &cirrus_encoder_helper_funcs);

 	return encoder;
 }


 static int cirrus_vga_get_modes(struct drm_connector *connector)
 {
 	int count;

 	/* Just add a static list of modes */
 	if (cirrus_bpp <= 24) {
 		count = drm_add_modes_noedid(connector, 1280, 1024);
 		drm_set_preferred_mode(connector, 1024, 768);
 	} else {
 		count = drm_add_modes_noedid(connector, 800, 600);
 		drm_set_preferred_mode(connector, 800, 600);
 	}
 	return count;
 }

 static struct drm_encoder *cirrus_connector_best_encoder(struct drm_connector
 						  *connector)
 {
 	int enc_id = connector->encoder_ids[0];
 	/* pick the encoder ids */
 	if (enc_id)
 		return drm_encoder_find(connector->dev, enc_id);
 	return NULL;
 }

 static enum drm_connector_status cirrus_vga_detect(struct drm_connector
 						   *connector, bool force)
 {
 	return connector_status_connected;
 }

 static void cirrus_connector_destroy(struct drm_connector *connector)
 {
 	drm_connector_cleanup(connector);
 	kfree(connector);
 }

 struct drm_connector_helper_funcs cirrus_vga_connector_helper_funcs = {
 	.get_modes = cirrus_vga_get_modes,
 	.best_encoder = cirrus_connector_best_encoder,
 };

 struct drm_connector_funcs cirrus_vga_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
 	.detect = cirrus_vga_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = cirrus_connector_destroy,
 };

 static struct drm_connector *cirrus_vga_init(struct drm_device *dev)
 {
 	struct drm_connector *connector;
 	struct cirrus_connector *cirrus_connector;

 	cirrus_connector = kzalloc(sizeof(struct cirrus_connector), GFP_KERNEL);
 	if (!cirrus_connector)
 		return NULL;

 	connector = &cirrus_connector->base;

 	drm_connector_init(dev, connector,
 			   &cirrus_vga_connector_funcs, DRM_MODE_CONNECTOR_VGA);

 	drm_connector_helper_add(connector, &cirrus_vga_connector_helper_funcs);

 	drm_connector_register(connector);
 	return connector;
 }


 int cirrus_modeset_init(struct cirrus_device *cdev)
 {
 	struct drm_encoder *encoder;
 	struct drm_connector *connector;
 	int ret;

 	drm_mode_config_init(cdev->dev);
 	cdev->mode_info.mode_config_initialized = true;

 	cdev->dev->mode_config.max_width = CIRRUS_MAX_FB_WIDTH;
 	cdev->dev->mode_config.max_height = CIRRUS_MAX_FB_HEIGHT;

 	cdev->dev->mode_config.fb_base = cdev->mc.vram_base;
 	cdev->dev->mode_config.preferred_depth = 24;
 	/* don't prefer a shadow on virt GPU */
 	cdev->dev->mode_config.prefer_shadow = 0;

 	cirrus_crtc_init(cdev->dev);

 	encoder = cirrus_encoder_init(cdev->dev);
 	if (!encoder) {
 		DRM_ERROR("cirrus_encoder_init failed\n");
 		return -1;
 	}

 	connector = cirrus_vga_init(cdev->dev);
 	if (!connector) {
 		DRM_ERROR("cirrus_vga_init failed\n");
 		return -1;
 	}

 	drm_mode_connector_attach_encoder(connector, encoder);

 	ret = cirrus_fbdev_init(cdev);
 	if (ret) {
 		DRM_ERROR("cirrus_fbdev_init failed\n");
 		return ret;
 	}

 	return 0;
 }

 void cirrus_modeset_fini(struct cirrus_device *cdev)
 {
 	cirrus_fbdev_fini(cdev);

 	if (cdev->mode_info.mode_config_initialized) {
 		drm_mode_config_cleanup(cdev->dev);
 		cdev->mode_info.mode_config_initialized = false;
 	}
 }

	/*
	* Copyright 2012 Red Hat
	*
	* This file is subject to the terms and conditions of the GNU General
	* Public License version 2. See the file COPYING in the main
	* directory of this archive for more details.
	*
	* Authors: Matthew Garrett
	* Dave Airlie
	*
	* Portions of this code derived from cirrusfb.c:
	* drivers/video/cirrusfb.c - driver for Cirrus Logic chipsets
	*
	* Copyright 1999-2001 Jeff Garzik <jgarzik@pobox.com>
	*/
	#include <drm/drmP.h>
	#include <drm/drm_crtc_helper.h>
	#include <drm/drm_plane_helper.h>

	#include <video/cirrus.h>

	#include "cirrus_drv.h"

	#define CIRRUS_LUT_SIZE 256

	#define PALETTE_INDEX 0x8
	#define PALETTE_DATA 0x9

	/*
	* This file contains setup code for the CRTC.
	*/

	static void cirrus_crtc_load_lut(struct drm_crtc *crtc)
	{
	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
	struct drm_device *dev = crtc->dev;
	struct cirrus_device *cdev = dev->dev_private;
	int i;

	if (!crtc->enabled)
	return;

	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
	/* VGA registers */
	WREG8(PALETTE_INDEX, i);
	WREG8(PALETTE_DATA, cirrus_crtc->lut_r[i]);
	WREG8(PALETTE_DATA, cirrus_crtc->lut_g[i]);
	WREG8(PALETTE_DATA, cirrus_crtc->lut_b[i]);
	}
	}

	/*
	* The DRM core requires DPMS functions, but they make little sense in our
	* case and so are just stubs
	*/

	static void cirrus_crtc_dpms(struct drm_crtc *crtc, int mode)
	{
	struct drm_device *dev = crtc->dev;
	struct cirrus_device *cdev = dev->dev_private;
	u8 sr01, gr0e;

	switch (mode) {
	case DRM_MODE_DPMS_ON:
	sr01 = 0x00;
	gr0e = 0x00;
	break;
	case DRM_MODE_DPMS_STANDBY:
	sr01 = 0x20;
	gr0e = 0x02;
	break;
	case DRM_MODE_DPMS_SUSPEND:
	sr01 = 0x20;
	gr0e = 0x04;
	break;
	case DRM_MODE_DPMS_OFF:
	sr01 = 0x20;
	gr0e = 0x06;
	break;
	default:
	return;
	}

	WREG8(SEQ_INDEX, 0x1);
	sr01 \|= RREG8(SEQ_DATA) & ~0x20;
	WREG_SEQ(0x1, sr01);

	WREG8(GFX_INDEX, 0xe);
	gr0e \|= RREG8(GFX_DATA) & ~0x06;
	WREG_GFX(0xe, gr0e);
	}

	/*
	* The core passes the desired mode to the CRTC code to see whether any
	* CRTC-specific modifications need to be made to it. We're in a position
	* to just pass that straight through, so this does nothing
	*/
	static bool cirrus_crtc_mode_fixup(struct drm_crtc *crtc,
	const struct drm_display_mode *mode,
	struct drm_display_mode *adjusted_mode)
	{
	return true;
	}

	static void cirrus_set_start_address(struct drm_crtc *crtc, unsigned offset)
	{
	struct cirrus_device *cdev = crtc->dev->dev_private;
	u32 addr;
	u8 tmp;

	addr = offset >> 2;
	WREG_CRT(0x0c, (u8)((addr >> 8) & 0xff));
	WREG_CRT(0x0d, (u8)(addr & 0xff));

	WREG8(CRT_INDEX, 0x1b);
	tmp = RREG8(CRT_DATA);
	tmp &= 0xf2;
	tmp \|= (addr >> 16) & 0x01;
	tmp \|= (addr >> 15) & 0x0c;
	WREG_CRT(0x1b, tmp);
	WREG8(CRT_INDEX, 0x1d);
	tmp = RREG8(CRT_DATA);
	tmp &= 0x7f;
	tmp \|= (addr >> 12) & 0x80;
	WREG_CRT(0x1d, tmp);
	}

	/* cirrus is different - we will force move buffers out of VRAM */
	static int cirrus_crtc_do_set_base(struct drm_crtc *crtc,
	struct drm_framebuffer *fb,
	int x, int y, int atomic)
	{
	struct cirrus_device *cdev = crtc->dev->dev_private;
	struct drm_gem_object *obj;
	struct cirrus_framebuffer *cirrus_fb;
	struct cirrus_bo *bo;
	int ret;
	u64 gpu_addr;

	/* push the previous fb to system ram */
	if (!atomic && fb) {
	cirrus_fb = to_cirrus_framebuffer(fb);
	obj = cirrus_fb->obj;
	bo = gem_to_cirrus_bo(obj);
	ret = cirrus_bo_reserve(bo, false);
	if (ret)
	return ret;
	cirrus_bo_push_sysram(bo);
	cirrus_bo_unreserve(bo);
	}

	cirrus_fb = to_cirrus_framebuffer(crtc->primary->fb);
	obj = cirrus_fb->obj;
	bo = gem_to_cirrus_bo(obj);

	ret = cirrus_bo_reserve(bo, false);
	if (ret)
	return ret;

	ret = cirrus_bo_pin(bo, TTM_PL_FLAG_VRAM, &gpu_addr);
	if (ret) {
	cirrus_bo_unreserve(bo);
	return ret;
	}

	if (&cdev->mode_info.gfbdev->gfb == cirrus_fb) {
	/* if pushing console in kmap it */
	ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
	if (ret)
	DRM_ERROR("failed to kmap fbcon\n");
	}
	cirrus_bo_unreserve(bo);

	cirrus_set_start_address(crtc, (u32)gpu_addr);
	return 0;
	}

	static int cirrus_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
	struct drm_framebuffer *old_fb)
	{
	return cirrus_crtc_do_set_base(crtc, old_fb, x, y, 0);
	}

	/*
	* The meat of this driver. The core passes us a mode and we have to program
	* it. The modesetting here is the bare minimum required to satisfy the qemu
	* emulation of this hardware, and running this against a real device is
	* likely to result in an inadequately programmed mode. We've already had
	* the opportunity to modify the mode, so whatever we receive here should
	* be something that can be correctly programmed and displayed
	*/
	static int cirrus_crtc_mode_set(struct drm_crtc *crtc,
	struct drm_display_mode *mode,
	struct drm_display_mode *adjusted_mode,
	int x, int y, struct drm_framebuffer *old_fb)
	{
	struct drm_device *dev = crtc->dev;
	struct cirrus_device *cdev = dev->dev_private;
	int hsyncstart, hsyncend, htotal, hdispend;
	int vtotal, vdispend;
	int tmp;
	int sr07 = 0, hdr = 0;

	htotal = mode->htotal / 8;
	hsyncend = mode->hsync_end / 8;
	hsyncstart = mode->hsync_start / 8;
	hdispend = mode->hdisplay / 8;

	vtotal = mode->vtotal;
	vdispend = mode->vdisplay;

	vdispend -= 1;
	vtotal -= 2;

	htotal -= 5;
	hdispend -= 1;
	hsyncstart += 1;
	hsyncend += 1;

	WREG_CRT(VGA_CRTC_V_SYNC_END, 0x20);
	WREG_CRT(VGA_CRTC_H_TOTAL, htotal);
	WREG_CRT(VGA_CRTC_H_DISP, hdispend);
	WREG_CRT(VGA_CRTC_H_SYNC_START, hsyncstart);
	WREG_CRT(VGA_CRTC_H_SYNC_END, hsyncend);
	WREG_CRT(VGA_CRTC_V_TOTAL, vtotal & 0xff);
	WREG_CRT(VGA_CRTC_V_DISP_END, vdispend & 0xff);

	tmp = 0x40;
	if ((vdispend + 1) & 512)
	tmp \|= 0x20;
	WREG_CRT(VGA_CRTC_MAX_SCAN, tmp);

	/*
	* Overflow bits for values that don't fit in the standard registers
	*/
	tmp = 16;
	if (vtotal & 256)
	tmp \|= 1;
	if (vdispend & 256)
	tmp \|= 2;
	if ((vdispend + 1) & 256)
	tmp \|= 8;
	if (vtotal & 512)
	tmp \|= 32;
	if (vdispend & 512)
	tmp \|= 64;
	WREG_CRT(VGA_CRTC_OVERFLOW, tmp);

	tmp = 0;

	/* More overflow bits */

	if ((htotal + 5) & 64)
	tmp \|= 16;
	if ((htotal + 5) & 128)
	tmp \|= 32;
	if (vtotal & 256)
	tmp \|= 64;
	if (vtotal & 512)
	tmp \|= 128;

	WREG_CRT(CL_CRT1A, tmp);

	/* Disable Hercules/CGA compatibility */
	WREG_CRT(VGA_CRTC_MODE, 0x03);

	WREG8(SEQ_INDEX, 0x7);
	sr07 = RREG8(SEQ_DATA);
	sr07 &= 0xe0;
	hdr = 0;
	switch (crtc->primary->fb->bits_per_pixel) {
	case 8:
	sr07 \|= 0x11;
	break;
	case 16:
	sr07 \|= 0x17;
	hdr = 0xc1;
	break;
	case 24:
	sr07 \|= 0x15;
	hdr = 0xc5;
	break;
	case 32:
	sr07 \|= 0x19;
	hdr = 0xc5;
	break;
	default:
	return -1;
	}

	WREG_SEQ(0x7, sr07);

	/* Program the pitch */
	tmp = crtc->primary->fb->pitches[0] / 8;
	WREG_CRT(VGA_CRTC_OFFSET, tmp);

	/* Enable extended blanking and pitch bits, and enable full memory */
	tmp = 0x22;
	tmp \|= (crtc->primary->fb->pitches[0] >> 7) & 0x10;
	tmp \|= (crtc->primary->fb->pitches[0] >> 6) & 0x40;
	WREG_CRT(0x1b, tmp);

	/* Enable high-colour modes */
	WREG_GFX(VGA_GFX_MODE, 0x40);

	/* And set graphics mode */
	WREG_GFX(VGA_GFX_MISC, 0x01);

	WREG_HDR(hdr);
	cirrus_crtc_do_set_base(crtc, old_fb, x, y, 0);

	/* Unblank (needed on S3 resume, vgabios doesn't do it then) */
	outb(0x20, 0x3c0);
	return 0;
	}

	/*
	* This is called before a mode is programmed. A typical use might be to
	* enable DPMS during the programming to avoid seeing intermediate stages,
	* but that's not relevant to us
	*/
	static void cirrus_crtc_prepare(struct drm_crtc *crtc)
	{
	}

	/*
	* This is called after a mode is programmed. It should reverse anything done
	* by the prepare function
	*/
	static void cirrus_crtc_commit(struct drm_crtc *crtc)
	{
	}

	/*
	* The core can pass us a set of gamma values to program. We actually only
	* use this for 8-bit mode so can't perform smooth fades on deeper modes,
	* but it's a requirement that we provide the function
	*/
	static void cirrus_crtc_gamma_set(struct drm_crtc crtc, u16 red, u16 *green,
	u16 *blue, uint32_t start, uint32_t size)
	{
	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
	int i;

	if (size != CIRRUS_LUT_SIZE)
	return;

	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
	cirrus_crtc->lut_r[i] = red[i];
	cirrus_crtc->lut_g[i] = green[i];
	cirrus_crtc->lut_b[i] = blue[i];
	}
	cirrus_crtc_load_lut(crtc);
	}

	/* Simple cleanup function */
	static void cirrus_crtc_destroy(struct drm_crtc *crtc)
	{
	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);

	drm_crtc_cleanup(crtc);
	kfree(cirrus_crtc);
	}

	/* These provide the minimum set of functions required to handle a CRTC */
	static const struct drm_crtc_funcs cirrus_crtc_funcs = {
	.gamma_set = cirrus_crtc_gamma_set,
	.set_config = drm_crtc_helper_set_config,
	.destroy = cirrus_crtc_destroy,
	};

	static const struct drm_crtc_helper_funcs cirrus_helper_funcs = {
	.dpms = cirrus_crtc_dpms,
	.mode_fixup = cirrus_crtc_mode_fixup,
	.mode_set = cirrus_crtc_mode_set,
	.mode_set_base = cirrus_crtc_mode_set_base,
	.prepare = cirrus_crtc_prepare,
	.commit = cirrus_crtc_commit,
	.load_lut = cirrus_crtc_load_lut,
	};

	/* CRTC setup */
	static void cirrus_crtc_init(struct drm_device *dev)
	{
	struct cirrus_device *cdev = dev->dev_private;
	struct cirrus_crtc *cirrus_crtc;
	int i;

	cirrus_crtc = kzalloc(sizeof(struct cirrus_crtc) +
	(CIRRUSFB_CONN_LIMIT * sizeof(struct drm_connector *)),
	GFP_KERNEL);

	if (cirrus_crtc == NULL)
	return;

	drm_crtc_init(dev, &cirrus_crtc->base, &cirrus_crtc_funcs);

	drm_mode_crtc_set_gamma_size(&cirrus_crtc->base, CIRRUS_LUT_SIZE);
	cdev->mode_info.crtc = cirrus_crtc;

	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
	cirrus_crtc->lut_r[i] = i;
	cirrus_crtc->lut_g[i] = i;
	cirrus_crtc->lut_b[i] = i;
	}

	drm_crtc_helper_add(&cirrus_crtc->base, &cirrus_helper_funcs);
	}

	/** Sets the color ramps on behalf of fbcon */
	void cirrus_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
	u16 blue, int regno)
	{
	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);

	cirrus_crtc->lut_r[regno] = red;
	cirrus_crtc->lut_g[regno] = green;
	cirrus_crtc->lut_b[regno] = blue;
	}

	/** Gets the color ramps on behalf of fbcon */
	void cirrus_crtc_fb_gamma_get(struct drm_crtc crtc, u16 red, u16 *green,
	u16 *blue, int regno)
	{
	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);

	*red = cirrus_crtc->lut_r[regno];
	*green = cirrus_crtc->lut_g[regno];
	*blue = cirrus_crtc->lut_b[regno];
	}


	static bool cirrus_encoder_mode_fixup(struct drm_encoder *encoder,
	const struct drm_display_mode *mode,
	struct drm_display_mode *adjusted_mode)
	{
	return true;
	}

	static void cirrus_encoder_mode_set(struct drm_encoder *encoder,
	struct drm_display_mode *mode,
	struct drm_display_mode *adjusted_mode)
	{
	}

	static void cirrus_encoder_dpms(struct drm_encoder *encoder, int state)
	{
	return;
	}

	static void cirrus_encoder_prepare(struct drm_encoder *encoder)
	{
	}

	static void cirrus_encoder_commit(struct drm_encoder *encoder)
	{
	}

	static void cirrus_encoder_destroy(struct drm_encoder *encoder)
	{
	struct cirrus_encoder *cirrus_encoder = to_cirrus_encoder(encoder);
	drm_encoder_cleanup(encoder);
	kfree(cirrus_encoder);
	}

	static const struct drm_encoder_helper_funcs cirrus_encoder_helper_funcs = {
	.dpms = cirrus_encoder_dpms,
	.mode_fixup = cirrus_encoder_mode_fixup,
	.mode_set = cirrus_encoder_mode_set,
	.prepare = cirrus_encoder_prepare,
	.commit = cirrus_encoder_commit,
	};

	static const struct drm_encoder_funcs cirrus_encoder_encoder_funcs = {
	.destroy = cirrus_encoder_destroy,
	};

	static struct drm_encoder cirrus_encoder_init(struct drm_device dev)
	{
	struct drm_encoder *encoder;
	struct cirrus_encoder *cirrus_encoder;

	cirrus_encoder = kzalloc(sizeof(struct cirrus_encoder), GFP_KERNEL);
	if (!cirrus_encoder)
	return NULL;

	encoder = &cirrus_encoder->base;
	encoder->possible_crtcs = 0x1;

	drm_encoder_init(dev, encoder, &cirrus_encoder_encoder_funcs,
	DRM_MODE_ENCODER_DAC, NULL);
	drm_encoder_helper_add(encoder, &cirrus_encoder_helper_funcs);

	return encoder;
	}


	static int cirrus_vga_get_modes(struct drm_connector *connector)
	{
	int count;

	/* Just add a static list of modes */
	if (cirrus_bpp <= 24) {
	count = drm_add_modes_noedid(connector, 1280, 1024);
	drm_set_preferred_mode(connector, 1024, 768);
	} else {
	count = drm_add_modes_noedid(connector, 800, 600);
	drm_set_preferred_mode(connector, 800, 600);
	}
	return count;
	}

	static struct drm_encoder *cirrus_connector_best_encoder(struct drm_connector
	*connector)
	{
	int enc_id = connector->encoder_ids[0];
	/* pick the encoder ids */
	if (enc_id)
	return drm_encoder_find(connector->dev, enc_id);
	return NULL;
	}

	static enum drm_connector_status cirrus_vga_detect(struct drm_connector
	*connector, bool force)
	{
	return connector_status_connected;
	}

	static void cirrus_connector_destroy(struct drm_connector *connector)
	{
	drm_connector_cleanup(connector);
	kfree(connector);
	}

	struct drm_connector_helper_funcs cirrus_vga_connector_helper_funcs = {
	.get_modes = cirrus_vga_get_modes,
	.best_encoder = cirrus_connector_best_encoder,
	};

	struct drm_connector_funcs cirrus_vga_connector_funcs = {
	.dpms = drm_helper_connector_dpms,
	.detect = cirrus_vga_detect,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.destroy = cirrus_connector_destroy,
	};

	static struct drm_connector cirrus_vga_init(struct drm_device dev)
	{
	struct drm_connector *connector;
	struct cirrus_connector *cirrus_connector;

	cirrus_connector = kzalloc(sizeof(struct cirrus_connector), GFP_KERNEL);
	if (!cirrus_connector)
	return NULL;

	connector = &cirrus_connector->base;

	drm_connector_init(dev, connector,
	&cirrus_vga_connector_funcs, DRM_MODE_CONNECTOR_VGA);

	drm_connector_helper_add(connector, &cirrus_vga_connector_helper_funcs);

	drm_connector_register(connector);
	return connector;
	}


	int cirrus_modeset_init(struct cirrus_device *cdev)
	{
	struct drm_encoder *encoder;
	struct drm_connector *connector;
	int ret;

	drm_mode_config_init(cdev->dev);
	cdev->mode_info.mode_config_initialized = true;

	cdev->dev->mode_config.max_width = CIRRUS_MAX_FB_WIDTH;
	cdev->dev->mode_config.max_height = CIRRUS_MAX_FB_HEIGHT;

	cdev->dev->mode_config.fb_base = cdev->mc.vram_base;
	cdev->dev->mode_config.preferred_depth = 24;
	/* don't prefer a shadow on virt GPU */
	cdev->dev->mode_config.prefer_shadow = 0;

	cirrus_crtc_init(cdev->dev);

	encoder = cirrus_encoder_init(cdev->dev);
	if (!encoder) {
	DRM_ERROR("cirrus_encoder_init failed\n");
	return -1;
	}

	connector = cirrus_vga_init(cdev->dev);
	if (!connector) {
	DRM_ERROR("cirrus_vga_init failed\n");
	return -1;
	}

	drm_mode_connector_attach_encoder(connector, encoder);

	ret = cirrus_fbdev_init(cdev);
	if (ret) {
	DRM_ERROR("cirrus_fbdev_init failed\n");
	return ret;
	}

	return 0;
	}

	void cirrus_modeset_fini(struct cirrus_device *cdev)
	{
	cirrus_fbdev_fini(cdev);

	if (cdev->mode_info.mode_config_initialized) {
	drm_mode_config_cleanup(cdev->dev);
	cdev->mode_info.mode_config_initialized = false;
	}
	}