drivers/gpu/drm/arm/hdlcd_crtc.c

   1 /*
   2  * Copyright (C) 2013-2015 ARM Limited
   3  * Author: Liviu Dudau <Liviu.Dudau@arm.com>
   4  *
   5  * This file is subject to the terms and conditions of the GNU General Public
   6  * License.  See the file COPYING in the main directory of this archive
   7  * for more details.
   8  *
   9  *  Implementation of a CRTC class for the HDLCD driver.
  10  */
  11
  12 #include <drm/drmP.h>
  13 #include <drm/drm_atomic_helper.h>
  14 #include <drm/drm_crtc.h>
  15 #include <drm/drm_crtc_helper.h>
  16 #include <drm/drm_fb_helper.h>
  17 #include <drm/drm_fb_cma_helper.h>
  18 #include <drm/drm_gem_cma_helper.h>
  19 #include <drm/drm_of.h>
  20 #include <drm/drm_plane_helper.h>
  21 #include <linux/clk.h>
  22 #include <linux/of_graph.h>
  23 #include <linux/platform_data/simplefb.h>
  24 #include <video/videomode.h>
  25
  26 #include "hdlcd_drv.h"
  27 #include "hdlcd_regs.h"
  28
  29 /*
  30  * The HDLCD controller is a dumb RGB streamer that gets connected to
  31  * a single HDMI transmitter or in the case of the ARM Models it gets
  32  * emulated by the software that does the actual rendering.
  33  *
  34  */
  35
  36 static void hdlcd_crtc_cleanup(struct drm_crtc *crtc)
  37 {
  38         struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
  39
  40         /* stop the controller on cleanup */
  41         hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
  42         drm_crtc_cleanup(crtc);
  43 }
  44
  45 static const struct drm_crtc_funcs hdlcd_crtc_funcs = {
  46         .destroy = hdlcd_crtc_cleanup,
  47         .set_config = drm_atomic_helper_set_config,
  48         .page_flip = drm_atomic_helper_page_flip,
  49         .reset = drm_atomic_helper_crtc_reset,
  50         .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
  51         .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
  52 };
  53
  54 static struct simplefb_format supported_formats[] = SIMPLEFB_FORMATS;
  55
  56 /*
  57  * Setup the HDLCD registers for decoding the pixels out of the framebuffer
  58  */
  59 static int hdlcd_set_pxl_fmt(struct drm_crtc *crtc)
  60 {
  61         unsigned int btpp;
  62         struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
  63         uint32_t pixel_format;
  64         struct simplefb_format *format = NULL;
  65         int i;
  66
  67         pixel_format = crtc->primary->state->fb->pixel_format;
  68
  69         for (i = 0; i < ARRAY_SIZE(supported_formats); i++) {
  70                 if (supported_formats[i].fourcc == pixel_format)
  71                         format = &supported_formats[i];
  72         }
  73
  74         if (WARN_ON(!format))
  75                 return 0;
  76
  77         /* HDLCD uses 'bytes per pixel', zero means 1 byte */
  78         btpp = (format->bits_per_pixel + 7) / 8;
  79         hdlcd_write(hdlcd, HDLCD_REG_PIXEL_FORMAT, (btpp - 1) << 3);
  80
  81         /*
  82          * The format of the HDLCD_REG_<color>_SELECT register is:
  83          *   - bits[23:16] - default value for that color component
  84          *   - bits[11:8]  - number of bits to extract for each color component
  85          *   - bits[4:0]   - index of the lowest bit to extract
  86          *
  87          * The default color value is used when bits[11:8] are zero, when the
  88          * pixel is outside the visible frame area or when there is a
  89          * buffer underrun.
  90          */
  91         hdlcd_write(hdlcd, HDLCD_REG_RED_SELECT, format->red.offset |
  92 #ifdef CONFIG_DRM_HDLCD_SHOW_UNDERRUN
  93                     0x00ff0000 |        /* show underruns in red */
  94 #endif
  95                     ((format->red.length & 0xf) << 8));
  96         hdlcd_write(hdlcd, HDLCD_REG_GREEN_SELECT, format->green.offset |
  97                     ((format->green.length & 0xf) << 8));
  98         hdlcd_write(hdlcd, HDLCD_REG_BLUE_SELECT, format->blue.offset |
  99                     ((format->blue.length & 0xf) << 8));
 100
 101         return 0;
 102 }
 103
 104 static void hdlcd_crtc_mode_set_nofb(struct drm_crtc *crtc)
 105 {
 106         struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
 107         struct drm_display_mode *m = &crtc->state->adjusted_mode;
 108         struct videomode vm;
 109         unsigned int polarities, err;
 110
 111         vm.vfront_porch = m->crtc_vsync_start - m->crtc_vdisplay;
 112         vm.vback_porch = m->crtc_vtotal - m->crtc_vsync_end;
 113         vm.vsync_len = m->crtc_vsync_end - m->crtc_vsync_start;
 114         vm.hfront_porch = m->crtc_hsync_start - m->crtc_hdisplay;
 115         vm.hback_porch = m->crtc_htotal - m->crtc_hsync_end;
 116         vm.hsync_len = m->crtc_hsync_end - m->crtc_hsync_start;
 117
 118         polarities = HDLCD_POLARITY_DATAEN | HDLCD_POLARITY_DATA;
 119
 120         if (m->flags & DRM_MODE_FLAG_PHSYNC)
 121                 polarities |= HDLCD_POLARITY_HSYNC;
 122         if (m->flags & DRM_MODE_FLAG_PVSYNC)
 123                 polarities |= HDLCD_POLARITY_VSYNC;
 124
 125         /* Allow max number of outstanding requests and largest burst size */
 126         hdlcd_write(hdlcd, HDLCD_REG_BUS_OPTIONS,
 127                     HDLCD_BUS_MAX_OUTSTAND | HDLCD_BUS_BURST_16);
 128
 129         hdlcd_write(hdlcd, HDLCD_REG_V_DATA, m->crtc_vdisplay - 1);
 130         hdlcd_write(hdlcd, HDLCD_REG_V_BACK_PORCH, vm.vback_porch - 1);
 131         hdlcd_write(hdlcd, HDLCD_REG_V_FRONT_PORCH, vm.vfront_porch - 1);
 132         hdlcd_write(hdlcd, HDLCD_REG_V_SYNC, vm.vsync_len - 1);
 133         hdlcd_write(hdlcd, HDLCD_REG_H_DATA, m->crtc_hdisplay - 1);
 134         hdlcd_write(hdlcd, HDLCD_REG_H_BACK_PORCH, vm.hback_porch - 1);
 135         hdlcd_write(hdlcd, HDLCD_REG_H_FRONT_PORCH, vm.hfront_porch - 1);
 136         hdlcd_write(hdlcd, HDLCD_REG_H_SYNC, vm.hsync_len - 1);
 137         hdlcd_write(hdlcd, HDLCD_REG_POLARITIES, polarities);
 138
 139         err = hdlcd_set_pxl_fmt(crtc);
 140         if (err)
 141                 return;
 142
 143         clk_set_rate(hdlcd->clk, m->crtc_clock * 1000);
 144 }
 145
 146 static void hdlcd_crtc_enable(struct drm_crtc *crtc)
 147 {
 148         struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
 149
 150         clk_prepare_enable(hdlcd->clk);
 151         hdlcd_crtc_mode_set_nofb(crtc);
 152         hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 1);
 153         drm_crtc_vblank_on(crtc);
 154 }
 155
 156 static void hdlcd_crtc_disable(struct drm_crtc *crtc)
 157 {
 158         struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
 159
 160         drm_crtc_vblank_off(crtc);
 161         hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
 162         clk_disable_unprepare(hdlcd->clk);
 163 }
 164
 165 static int hdlcd_crtc_atomic_check(struct drm_crtc *crtc,
 166                                    struct drm_crtc_state *state)
 167 {
 168         struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
 169         struct drm_display_mode *mode = &state->adjusted_mode;
 170         long rate, clk_rate = mode->clock * 1000;
 171
 172         rate = clk_round_rate(hdlcd->clk, clk_rate);
 173         /* 0.1% seems a close enough tolerance for the TDA19988 on Juno */
 174         if (abs(rate - clk_rate) * 1000 > clk_rate) {
 175                 /* clock required by mode not supported by hardware */
 176                 return -EINVAL;
 177         }
 178
 179         return 0;
 180 }
 181
 182 static void hdlcd_crtc_atomic_begin(struct drm_crtc *crtc,
 183                                     struct drm_crtc_state *state)
 184 {
 185         struct drm_pending_vblank_event *event = crtc->state->event;
 186
 187         if (event) {
 188                 crtc->state->event = NULL;
 189
 190                 spin_lock_irq(&crtc->dev->event_lock);
 191                 if (drm_crtc_vblank_get(crtc) == 0)
 192                         drm_crtc_arm_vblank_event(crtc, event);
 193                 else
 194                         drm_crtc_send_vblank_event(crtc, event);
 195                 spin_unlock_irq(&crtc->dev->event_lock);
 196         }
 197 }
 198
 199 static const struct drm_crtc_helper_funcs hdlcd_crtc_helper_funcs = {
 200         .enable         = hdlcd_crtc_enable,
 201         .disable        = hdlcd_crtc_disable,
 202         .atomic_check   = hdlcd_crtc_atomic_check,
 203         .atomic_begin   = hdlcd_crtc_atomic_begin,
 204 };
 205
 206 static int hdlcd_plane_atomic_check(struct drm_plane *plane,
 207                                     struct drm_plane_state *state)
 208 {
 209         u32 src_w, src_h;
 210
 211         src_w = state->src_w >> 16;
 212         src_h = state->src_h >> 16;
 213
 214         /* we can't do any scaling of the plane source */
 215         if ((src_w != state->crtc_w) || (src_h != state->crtc_h))
 216                 return -EINVAL;
 217
 218         return 0;
 219 }
 220
 221 static void hdlcd_plane_atomic_update(struct drm_plane *plane,
 222                                       struct drm_plane_state *state)
 223 {
 224         struct hdlcd_drm_private *hdlcd;
 225         struct drm_gem_cma_object *gem;
 226         unsigned int depth, bpp;
 227         u32 src_w, src_h, dest_w, dest_h;
 228         dma_addr_t scanout_start;
 229
 230         if (!plane->state->fb)
 231                 return;
 232
 233         drm_fb_get_bpp_depth(plane->state->fb->pixel_format, &depth, &bpp);
 234         src_w = plane->state->src_w >> 16;
 235         src_h = plane->state->src_h >> 16;
 236         dest_w = plane->state->crtc_w;
 237         dest_h = plane->state->crtc_h;
 238         gem = drm_fb_cma_get_gem_obj(plane->state->fb, 0);
 239         scanout_start = gem->paddr + plane->state->fb->offsets[0] +
 240                 plane->state->crtc_y * plane->state->fb->pitches[0] +
 241                 plane->state->crtc_x * bpp / 8;
 242
 243         hdlcd = plane->dev->dev_private;
 244         hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_LENGTH, plane->state->fb->pitches[0]);
 245         hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_PITCH, plane->state->fb->pitches[0]);
 246         hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_COUNT, dest_h - 1);
 247         hdlcd_write(hdlcd, HDLCD_REG_FB_BASE, scanout_start);
 248 }
 249
 250 static const struct drm_plane_helper_funcs hdlcd_plane_helper_funcs = {
 251         .atomic_check = hdlcd_plane_atomic_check,
 252         .atomic_update = hdlcd_plane_atomic_update,
 253 };
 254
 255 static void hdlcd_plane_destroy(struct drm_plane *plane)
 256 {
 257         drm_plane_helper_disable(plane);
 258         drm_plane_cleanup(plane);
 259 }
 260
 261 static const struct drm_plane_funcs hdlcd_plane_funcs = {
 262         .update_plane           = drm_atomic_helper_update_plane,
 263         .disable_plane          = drm_atomic_helper_disable_plane,
 264         .destroy                = hdlcd_plane_destroy,
 265         .reset                  = drm_atomic_helper_plane_reset,
 266         .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
 267         .atomic_destroy_state   = drm_atomic_helper_plane_destroy_state,
 268 };
 269
 270 static struct drm_plane *hdlcd_plane_init(struct drm_device *drm)
 271 {
 272         struct hdlcd_drm_private *hdlcd = drm->dev_private;
 273         struct drm_plane *plane = NULL;
 274         u32 formats[ARRAY_SIZE(supported_formats)], i;
 275         int ret;
 276
 277         plane = devm_kzalloc(drm->dev, sizeof(*plane), GFP_KERNEL);
 278         if (!plane)
 279                 return ERR_PTR(-ENOMEM);
 280
 281         for (i = 0; i < ARRAY_SIZE(supported_formats); i++)
 282                 formats[i] = supported_formats[i].fourcc;
 283
 284         ret = drm_universal_plane_init(drm, plane, 0xff, &hdlcd_plane_funcs,
 285                                        formats, ARRAY_SIZE(formats),
 286                                        DRM_PLANE_TYPE_PRIMARY, NULL);
 287         if (ret) {
 288                 devm_kfree(drm->dev, plane);
 289                 return ERR_PTR(ret);
 290         }
 291
 292         drm_plane_helper_add(plane, &hdlcd_plane_helper_funcs);
 293         hdlcd->plane = plane;
 294
 295         return plane;
 296 }
 297
 298 int hdlcd_setup_crtc(struct drm_device *drm)
 299 {
 300         struct hdlcd_drm_private *hdlcd = drm->dev_private;
 301         struct drm_plane *primary;
 302         int ret;
 303
 304         primary = hdlcd_plane_init(drm);
 305         if (IS_ERR(primary))
 306                 return PTR_ERR(primary);
 307
 308         ret = drm_crtc_init_with_planes(drm, &hdlcd->crtc, primary, NULL,
 309                                         &hdlcd_crtc_funcs, NULL);
 310         if (ret) {
 311                 hdlcd_plane_destroy(primary);
 312                 devm_kfree(drm->dev, primary);
 313                 return ret;
 314         }
 315
 316         drm_crtc_helper_add(&hdlcd->crtc, &hdlcd_crtc_helper_funcs);
 317         return 0;
 318 }