diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/video/fbdev/core/fbcvt.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/video/fbdev/core/fbcvt.c')
-rw-r--r-- | drivers/video/fbdev/core/fbcvt.c | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/fbcvt.c b/drivers/video/fbdev/core/fbcvt.c new file mode 100644 index 0000000000..64843464c6 --- /dev/null +++ b/drivers/video/fbdev/core/fbcvt.c @@ -0,0 +1,368 @@ +/* + * linux/drivers/video/fbcvt.c - VESA(TM) Coordinated Video Timings + * + * Copyright (C) 2005 Antonino Daplas <adaplas@pol.net> + * + * Based from the VESA(TM) Coordinated Video Timing Generator by + * Graham Loveridge April 9, 2003 available at + * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + * + */ +#include <linux/fb.h> +#include <linux/slab.h> + +#define FB_CVT_CELLSIZE 8 +#define FB_CVT_GTF_C 40 +#define FB_CVT_GTF_J 20 +#define FB_CVT_GTF_K 128 +#define FB_CVT_GTF_M 600 +#define FB_CVT_MIN_VSYNC_BP 550 +#define FB_CVT_MIN_VPORCH 3 +#define FB_CVT_MIN_BPORCH 6 + +#define FB_CVT_RB_MIN_VBLANK 460 +#define FB_CVT_RB_HBLANK 160 +#define FB_CVT_RB_V_FPORCH 3 + +#define FB_CVT_FLAG_REDUCED_BLANK 1 +#define FB_CVT_FLAG_MARGINS 2 +#define FB_CVT_FLAG_INTERLACED 4 + +struct fb_cvt_data { + u32 xres; + u32 yres; + u32 refresh; + u32 f_refresh; + u32 pixclock; + u32 hperiod; + u32 hblank; + u32 hfreq; + u32 htotal; + u32 vtotal; + u32 vsync; + u32 hsync; + u32 h_front_porch; + u32 h_back_porch; + u32 v_front_porch; + u32 v_back_porch; + u32 h_margin; + u32 v_margin; + u32 interlace; + u32 aspect_ratio; + u32 active_pixels; + u32 flags; + u32 status; +}; + +static const unsigned char fb_cvt_vbi_tab[] = { + 4, /* 4:3 */ + 5, /* 16:9 */ + 6, /* 16:10 */ + 7, /* 5:4 */ + 7, /* 15:9 */ + 8, /* reserved */ + 9, /* reserved */ + 10 /* custom */ +}; + +/* returns hperiod * 1000 */ +static u32 fb_cvt_hperiod(struct fb_cvt_data *cvt) +{ + u32 num = 1000000000/cvt->f_refresh; + u32 den; + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) { + num -= FB_CVT_RB_MIN_VBLANK * 1000; + den = 2 * (cvt->yres/cvt->interlace + 2 * cvt->v_margin); + } else { + num -= FB_CVT_MIN_VSYNC_BP * 1000; + den = 2 * (cvt->yres/cvt->interlace + cvt->v_margin * 2 + + FB_CVT_MIN_VPORCH + cvt->interlace/2); + } + + return 2 * (num/den); +} + +/* returns ideal duty cycle * 1000 */ +static u32 fb_cvt_ideal_duty_cycle(struct fb_cvt_data *cvt) +{ + u32 c_prime = (FB_CVT_GTF_C - FB_CVT_GTF_J) * + (FB_CVT_GTF_K) + 256 * FB_CVT_GTF_J; + u32 m_prime = (FB_CVT_GTF_K * FB_CVT_GTF_M); + u32 h_period_est = cvt->hperiod; + + return (1000 * c_prime - ((m_prime * h_period_est)/1000))/256; +} + +static u32 fb_cvt_hblank(struct fb_cvt_data *cvt) +{ + u32 hblank = 0; + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) + hblank = FB_CVT_RB_HBLANK; + else { + u32 ideal_duty_cycle = fb_cvt_ideal_duty_cycle(cvt); + u32 active_pixels = cvt->active_pixels; + + if (ideal_duty_cycle < 20000) + hblank = (active_pixels * 20000)/ + (100000 - 20000); + else { + hblank = (active_pixels * ideal_duty_cycle)/ + (100000 - ideal_duty_cycle); + } + } + + hblank &= ~((2 * FB_CVT_CELLSIZE) - 1); + + return hblank; +} + +static u32 fb_cvt_hsync(struct fb_cvt_data *cvt) +{ + u32 hsync; + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) + hsync = 32; + else + hsync = (FB_CVT_CELLSIZE * cvt->htotal)/100; + + hsync &= ~(FB_CVT_CELLSIZE - 1); + return hsync; +} + +static u32 fb_cvt_vbi_lines(struct fb_cvt_data *cvt) +{ + u32 vbi_lines, min_vbi_lines, act_vbi_lines; + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) { + vbi_lines = (1000 * FB_CVT_RB_MIN_VBLANK)/cvt->hperiod + 1; + min_vbi_lines = FB_CVT_RB_V_FPORCH + cvt->vsync + + FB_CVT_MIN_BPORCH; + + } else { + vbi_lines = (FB_CVT_MIN_VSYNC_BP * 1000)/cvt->hperiod + 1 + + FB_CVT_MIN_VPORCH; + min_vbi_lines = cvt->vsync + FB_CVT_MIN_BPORCH + + FB_CVT_MIN_VPORCH; + } + + if (vbi_lines < min_vbi_lines) + act_vbi_lines = min_vbi_lines; + else + act_vbi_lines = vbi_lines; + + return act_vbi_lines; +} + +static u32 fb_cvt_vtotal(struct fb_cvt_data *cvt) +{ + u32 vtotal = cvt->yres/cvt->interlace; + + vtotal += 2 * cvt->v_margin + cvt->interlace/2 + fb_cvt_vbi_lines(cvt); + vtotal |= cvt->interlace/2; + + return vtotal; +} + +static u32 fb_cvt_pixclock(struct fb_cvt_data *cvt) +{ + u32 pixclock; + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) + pixclock = (cvt->f_refresh * cvt->vtotal * cvt->htotal)/1000; + else + pixclock = (cvt->htotal * 1000000)/cvt->hperiod; + + pixclock /= 250; + pixclock *= 250; + pixclock *= 1000; + + return pixclock; +} + +static u32 fb_cvt_aspect_ratio(struct fb_cvt_data *cvt) +{ + u32 xres = cvt->xres; + u32 yres = cvt->yres; + u32 aspect = -1; + + if (xres == (yres * 4)/3 && !((yres * 4) % 3)) + aspect = 0; + else if (xres == (yres * 16)/9 && !((yres * 16) % 9)) + aspect = 1; + else if (xres == (yres * 16)/10 && !((yres * 16) % 10)) + aspect = 2; + else if (xres == (yres * 5)/4 && !((yres * 5) % 4)) + aspect = 3; + else if (xres == (yres * 15)/9 && !((yres * 15) % 9)) + aspect = 4; + else { + printk(KERN_INFO "fbcvt: Aspect ratio not CVT " + "standard\n"); + aspect = 7; + cvt->status = 1; + } + + return aspect; +} + +static void fb_cvt_print_name(struct fb_cvt_data *cvt) +{ + u32 pixcount, pixcount_mod; + int size = 256; + int off = 0; + u8 *buf; + + buf = kzalloc(size, GFP_KERNEL); + if (!buf) + return; + + pixcount = (cvt->xres * (cvt->yres/cvt->interlace))/1000000; + pixcount_mod = (cvt->xres * (cvt->yres/cvt->interlace)) % 1000000; + pixcount_mod /= 1000; + + off += scnprintf(buf + off, size - off, "fbcvt: %dx%d@%d: CVT Name - ", + cvt->xres, cvt->yres, cvt->refresh); + + if (cvt->status) { + off += scnprintf(buf + off, size - off, + "Not a CVT standard - %d.%03d Mega Pixel Image\n", + pixcount, pixcount_mod); + } else { + if (pixcount) + off += scnprintf(buf + off, size - off, "%d", pixcount); + + off += scnprintf(buf + off, size - off, ".%03dM", pixcount_mod); + + if (cvt->aspect_ratio == 0) + off += scnprintf(buf + off, size - off, "3"); + else if (cvt->aspect_ratio == 3) + off += scnprintf(buf + off, size - off, "4"); + else if (cvt->aspect_ratio == 1 || cvt->aspect_ratio == 4) + off += scnprintf(buf + off, size - off, "9"); + else if (cvt->aspect_ratio == 2) + off += scnprintf(buf + off, size - off, "A"); + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) + off += scnprintf(buf + off, size - off, "-R"); + } + + printk(KERN_INFO "%s\n", buf); + kfree(buf); +} + +static void fb_cvt_convert_to_mode(struct fb_cvt_data *cvt, + struct fb_videomode *mode) +{ + mode->refresh = cvt->f_refresh; + mode->pixclock = KHZ2PICOS(cvt->pixclock/1000); + mode->left_margin = cvt->h_back_porch; + mode->right_margin = cvt->h_front_porch; + mode->hsync_len = cvt->hsync; + mode->upper_margin = cvt->v_back_porch; + mode->lower_margin = cvt->v_front_porch; + mode->vsync_len = cvt->vsync; + + mode->sync &= ~(FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT); + + if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) + mode->sync |= FB_SYNC_HOR_HIGH_ACT; + else + mode->sync |= FB_SYNC_VERT_HIGH_ACT; +} + +/* + * fb_find_mode_cvt - calculate mode using VESA(TM) CVT + * @mode: pointer to fb_videomode; xres, yres, refresh and vmode must be + * pre-filled with the desired values + * @margins: add margin to calculation (1.8% of xres and yres) + * @rb: compute with reduced blanking (for flatpanels) + * + * RETURNS: + * 0 for success + * @mode is filled with computed values. If interlaced, the refresh field + * will be filled with the field rate (2x the frame rate) + * + * DESCRIPTION: + * Computes video timings using VESA(TM) Coordinated Video Timings + */ +int fb_find_mode_cvt(struct fb_videomode *mode, int margins, int rb) +{ + struct fb_cvt_data cvt; + + memset(&cvt, 0, sizeof(cvt)); + + if (margins) + cvt.flags |= FB_CVT_FLAG_MARGINS; + + if (rb) + cvt.flags |= FB_CVT_FLAG_REDUCED_BLANK; + + if (mode->vmode & FB_VMODE_INTERLACED) + cvt.flags |= FB_CVT_FLAG_INTERLACED; + + cvt.xres = mode->xres; + cvt.yres = mode->yres; + cvt.refresh = mode->refresh; + cvt.f_refresh = cvt.refresh; + cvt.interlace = 1; + + if (!cvt.xres || !cvt.yres || !cvt.refresh) { + printk(KERN_INFO "fbcvt: Invalid input parameters\n"); + return 1; + } + + if (!(cvt.refresh == 50 || cvt.refresh == 60 || cvt.refresh == 70 || + cvt.refresh == 85)) { + printk(KERN_INFO "fbcvt: Refresh rate not CVT " + "standard\n"); + cvt.status = 1; + } + + cvt.xres &= ~(FB_CVT_CELLSIZE - 1); + + if (cvt.flags & FB_CVT_FLAG_INTERLACED) { + cvt.interlace = 2; + cvt.f_refresh *= 2; + } + + if (cvt.flags & FB_CVT_FLAG_REDUCED_BLANK) { + if (cvt.refresh != 60) { + printk(KERN_INFO "fbcvt: 60Hz refresh rate " + "advised for reduced blanking\n"); + cvt.status = 1; + } + } + + if (cvt.flags & FB_CVT_FLAG_MARGINS) { + cvt.h_margin = (cvt.xres * 18)/1000; + cvt.h_margin &= ~(FB_CVT_CELLSIZE - 1); + cvt.v_margin = ((cvt.yres/cvt.interlace)* 18)/1000; + } + + cvt.aspect_ratio = fb_cvt_aspect_ratio(&cvt); + cvt.active_pixels = cvt.xres + 2 * cvt.h_margin; + cvt.hperiod = fb_cvt_hperiod(&cvt); + cvt.vsync = fb_cvt_vbi_tab[cvt.aspect_ratio]; + cvt.vtotal = fb_cvt_vtotal(&cvt); + cvt.hblank = fb_cvt_hblank(&cvt); + cvt.htotal = cvt.active_pixels + cvt.hblank; + cvt.hsync = fb_cvt_hsync(&cvt); + cvt.pixclock = fb_cvt_pixclock(&cvt); + cvt.hfreq = cvt.pixclock/cvt.htotal; + cvt.h_back_porch = cvt.hblank/2 + cvt.h_margin; + cvt.h_front_porch = cvt.hblank - cvt.hsync - cvt.h_back_porch + + 2 * cvt.h_margin; + cvt.v_front_porch = 3 + cvt.v_margin; + cvt.v_back_porch = cvt.vtotal - cvt.yres/cvt.interlace - + cvt.v_front_porch - cvt.vsync; + fb_cvt_print_name(&cvt); + fb_cvt_convert_to_mode(&cvt, mode); + + return 0; +} |