Commit cb740a08 authored by Robert Chiras's avatar Robert Chiras Committed by Guido Gunther
Browse files

drm/mxsfb: Add max-memory-bandwidth property for MXSFB



Because of stability issues, we may want to limit the maximum bandwidth
required by the MXSFB (eLCDIF) driver.
Signed-off-by: default avatarRobert Chiras <robert.chiras@nxp.com>
parent 2812c3c5
......@@ -161,6 +161,49 @@ static const struct drm_mode_config_helper_funcs mxsfb_mode_config_helpers = {
.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
};
enum drm_mode_status mxsfb_pipe_mode_valid(struct drm_crtc *crtc,
const struct drm_display_mode *mode)
{
struct drm_simple_display_pipe *pipe =
container_of(crtc, struct drm_simple_display_pipe, crtc);
struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
u32 bpp;
u64 bw;
if (!pipe->plane.state->fb)
bpp = 32;
else
bpp = pipe->plane.state->fb->format->depth;
bw = mode->crtc_clock * 1000;
bw = bw * mode->hdisplay * mode->vdisplay * (bpp / 8);
bw = div_u64(bw, mode->htotal * mode->vtotal);
if (mxsfb->max_bw && (bw > mxsfb->max_bw))
return MODE_BAD;
return MODE_OK;
}
static int mxsfb_pipe_check(struct drm_simple_display_pipe *pipe,
struct drm_plane_state *plane_state,
struct drm_crtc_state *crtc_state)
{
struct drm_framebuffer *fb = plane_state->fb;
struct drm_framebuffer *old_fb = pipe->plane.state->fb;
/* force 'mode_changed' when fb pitches changed, since
* the pitch related registers configuration of LCDIF
* can not be done when LCDIF is running.
*/
if (old_fb && likely(!crtc_state->mode_changed)) {
if (old_fb->pitches[0] != fb->pitches[0])
crtc_state->mode_changed = true;
}
return 0;
}
static void mxsfb_pipe_enable(struct drm_simple_display_pipe *pipe,
struct drm_crtc_state *crtc_state,
struct drm_plane_state *plane_state)
......@@ -251,6 +294,8 @@ static void mxsfb_pipe_disable_vblank(struct drm_simple_display_pipe *pipe)
}
static struct drm_simple_display_pipe_funcs mxsfb_funcs = {
.mode_valid = mxsfb_pipe_mode_valid,
.check = mxsfb_pipe_check,
.enable = mxsfb_pipe_enable,
.disable = mxsfb_pipe_disable,
.update = mxsfb_pipe_update,
......@@ -290,6 +335,9 @@ static int mxsfb_load(struct drm_device *drm, unsigned long flags)
if (IS_ERR(mxsfb->clk_disp_axi))
mxsfb->clk_disp_axi = NULL;
of_property_read_u32(drm->dev->of_node, "max-memory-bandwidth",
&mxsfb->max_bw);
ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
if (ret)
return ret;
......
......@@ -32,6 +32,8 @@ struct mxsfb_drm_private {
struct drm_connector *connector;
struct drm_panel *panel;
struct drm_bridge *bridge;
u32 max_bw;
};
int mxsfb_setup_crtc(struct drm_device *dev);
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment