Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c | 150 +++++++++++++++++++-
1 file changed, 149 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c b/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c
index 3473b85acbf1..87f56ec76edf 100644
--- a/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c
+++ b/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c
@@ -18,10 +18,18 @@
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_modeset_helper.h>
#include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
#include <linux/fb.h>
+#include "fbdevdrm_modes.h"
#include "fbdevdrm_primary.h"
+static struct fbdevdrm_modeset* fbdevdrm_modeset_of_crtc(
+ struct drm_crtc *crtc)
+{
+ return container_of(crtc, struct fbdevdrm_modeset, crtc);
+}
+
/*
* CRTC
*/
@@ -29,18 +37,124 @@
static enum drm_mode_status crtc_helper_mode_valid(
struct drm_crtc *crtc, const struct drm_display_mode *mode)
{
+ static const unsigned char bits_per_pixel[] = {
+ 32, 16, 8, 24, 15
+ };
+
+ struct fbdevdrm_modeset *modeset;
+ struct fb_var_screeninfo fb_var;
+ size_t i;
+ int ret;
+
+ modeset = fbdevdrm_modeset_of_crtc(crtc);
+
+ if (!modeset->fb_info->fbops->fb_check_var)
+ return MODE_OK;
+
+ for (i = 0; i < ARRAY_SIZE(bits_per_pixel); ++i) {
+
+ memcpy(&fb_var, &modeset->fb_info->var, sizeof(fb_var));
+ fbdevdrm_update_fb_var_screeninfo_from_mode(&fb_var, mode);
+ fb_var.bits_per_pixel = bits_per_pixel[i];
+
+ ret = modeset->fb_info->fbops->fb_check_var(&fb_var, modeset->fb_info);
+ if (ret)
+ continue; /* generally not supported */
+ if ((mode->hdisplay != fb_var.xres) ||
+ (mode->vdisplay != fb_var.yres))
+ continue; /* unsupported resolution */
+ if (KHZ2PICOS(mode->clock) != fb_var.pixclock)
+ continue; /* unsupported pixel clock */
+
+ break; /* mode successfully tested */
+ }
+ if (i == ARRAY_SIZE(bits_per_pixel))
+ return MODE_BAD; /* mode is not support */
+
return MODE_OK;
}
+static int fbdevdrm_update_fb_var_screeninfo_from_crtc(
+ struct fb_var_screeninfo *fb_var, struct drm_crtc* crtc)
+{
+ struct drm_plane *primary = crtc->primary;
+ struct fbdevdrm_modeset *modeset = fbdevdrm_modeset_of_crtc(crtc);
+
+ if (primary && primary->state && primary->state->fb)
+ return fbdevdrm_update_fb_var_screeninfo_from_framebuffer(
+ fb_var, primary->state->fb,
+ modeset->fb_info->fix.smem_len);
+
+ fb_var->xres_virtual = fb_var->xres;
+ fb_var->yres_virtual = fb_var->yres;
+ fb_var->bits_per_pixel = modeset->dev->mode_config.preferred_depth;
+
+ return 0;
+}
+
static bool crtc_helper_mode_fixup(struct drm_crtc *crtc,
const struct drm_display_mode *mode,
struct drm_display_mode *adjusted_mode)
{
+ struct fbdevdrm_modeset *modeset;
+ struct fb_var_screeninfo fb_var;
+ int ret;
+
+ modeset = fbdevdrm_modeset_of_crtc(crtc);
+
+ if (!modeset->fb_info->fbops->fb_check_var)
+ return true;
+
+ fbdevdrm_init_fb_var_screeninfo_from_mode(&fb_var, mode);
+
+ ret = fbdevdrm_update_fb_var_screeninfo_from_crtc(&fb_var, crtc);
+ if (ret)
+ return true;
+
+ ret = modeset->fb_info->fbops->fb_check_var(&fb_var, modeset->fb_info);
+ if (ret < 0)
+ return false;
+
+ drm_mode_update_from_fb_var_screeninfo(adjusted_mode, &fb_var);
+
return true;
}
static void crtc_helper_mode_set_nofb(struct drm_crtc *crtc)
-{ }
+{
+ struct fbdevdrm_modeset *modeset;
+ struct fb_var_screeninfo fb_var;
+ int ret;
+
+ /* As this is atomic mode setting, any function call is not
+ * allowed to fail. If it does, an additional test should be
+ * added to crtc_helper_atomic_check().
+ */
+
+ modeset = fbdevdrm_modeset_of_crtc(crtc);
+
+ memset(&fb_var, 0, sizeof(fb_var));
+ fbdevdrm_update_fb_var_screeninfo_from_mode(&fb_var, &crtc->state->adjusted_mode);
+
+ if (crtc->primary && crtc->primary->state && crtc->primary->state->fb) {
+ ret = fbdevdrm_update_fb_var_screeninfo_from_framebuffer(
+ &fb_var, crtc->primary->state->fb,
+ modeset->fb_info->fix.smem_len);
+ if (ret)
+ return;
+ } else {
+ fb_var.xres_virtual = fb_var.xres;
+ fb_var.yres_virtual = fb_var.yres;
+ }
+
+ fb_var.activate = FB_ACTIVATE_NOW;
+
+ ret = fb_set_var(modeset->fb_info, &fb_var);
+ if (ret) {
+ DRM_ERROR("fbdevdrm: fb_set_var() failed: %d\n", ret);
+ return;
+ }
+}
static int crtc_helper_mode_set_base_atomic(struct drm_crtc *crtc,
struct drm_framebuffer *fb,
@@ -53,6 +167,40 @@ static int crtc_helper_mode_set_base_atomic(struct drm_crtc *crtc,
static int crtc_helper_atomic_check(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
+ struct fbdevdrm_modeset *modeset;
+ struct fb_videomode fb_mode, fb_var_mode;
+
+ modeset = fbdevdrm_modeset_of_crtc(crtc);
+
+ /* DRM porting notes: when fbcon takes over the console, it regularly
+ * changes the display mode. Where's apparently no way to detect this
+ * directly from fbcon itself. DRM's mode information might therefore
+ * be out of data, after it takes over the display at a later time.
+ * Here, we test the CRTC's current mode with the fbdev state. If they
+ * do not match, we request a mode change from DRM. If you port an
+ * fbdev driver to DRM, you can remove this code section, DRM will
+ * be in full control of the display device and doesn't have to react
+ * to changes from external sources.
+ */
+
+ if (!state->mode_changed && state->adjusted_mode.clock) {
+ fbdevdrm_init_fb_videomode_from_mode(&fb_mode, &state->adjusted_mode);
+ fb_var_to_videomode(&fb_var_mode, &modeset->fb_info->var);
+ if (!fb_mode_is_equal(&fb_mode, &fb_var_mode))
+ state->mode_changed = true;
+ }
+
+ /* TODO: The vblank interupt is currently not supported. We set
+ * the corresponding flag as a workaround. Some fbdev drivers
+ * support FBIO_WAITFORVSYNC, which we might use for querying
+ * vblanks.
+ *
+ * DRM porting notes: if you're porting an fbdev driver to DRM,
+ * remove this line and instead signal a vblank event from the
+ * interupt handler.
+ */
+ state->no_vblank = true;
+
return 0;
}
--
2.21.0
