diff options
author | Philippe CORNU <philippe.cornu@st.com> | 2018-01-25 17:01:01 +0100 |
---|---|---|
committer | Benjamin Gaignard <benjamin.gaignard@linaro.org> | 2018-01-29 11:07:16 +0100 |
commit | 1a32a938b6438afe70c0a2a6dd666f4a49f6c384 (patch) | |
tree | d04395cac7edff153153d4a69ead2b2dbca7dff9 /drivers | |
parent | 41d2f5fa89e3fa772ea27c0e1b7bf0e7c6f295b1 (diff) |
drm/stm: ltdc: use crtc_mode_fixup to update adjusted_mode clock
There is a difference between the panel/bridge requested pixel clock
value and the real one due to the hw platform clock preciseness (pll,
dividers...). This patch updates the adjusted_mode clock value with
the real hw clock value so then attached encoder & connector can use
it for precise timing computations.
Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
Reviewed-by: Yannick Fertré <yannick.fertre@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180125160101.9102-1-philippe.cornu@st.com
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/gpu/drm/stm/ltdc.c | 35 |
1 files changed, 25 insertions, 10 deletions
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index b48589343ae1..90b3de516c91 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -428,12 +428,35 @@ static void ltdc_crtc_atomic_disable(struct drm_crtc *crtc, reg_set(ldev->regs, LTDC_SRCR, SRCR_IMR); } +static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode) +{ + struct ltdc_device *ldev = crtc_to_ltdc(crtc); + int rate = mode->clock * 1000; + + /* + * TODO clk_round_rate() does not work yet. When ready, it can + * be used instead of clk_set_rate() then clk_get_rate(). + */ + + clk_disable(ldev->pixel_clk); + if (clk_set_rate(ldev->pixel_clk, rate) < 0) { + DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate); + return false; + } + clk_enable(ldev->pixel_clk); + + adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000; + + return true; +} + static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc) { struct ltdc_device *ldev = crtc_to_ltdc(crtc); struct drm_display_mode *mode = &crtc->state->adjusted_mode; struct videomode vm; - int rate = mode->clock * 1000; u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h; u32 total_width, total_height; u32 val; @@ -456,15 +479,6 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc) total_width = accum_act_w + vm.hfront_porch; total_height = accum_act_h + vm.vfront_porch; - clk_disable(ldev->pixel_clk); - - if (clk_set_rate(ldev->pixel_clk, rate) < 0) { - DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate); - return; - } - - clk_enable(ldev->pixel_clk); - /* Configures the HS, VS, DE and PC polarities. Default Active Low */ val = 0; @@ -528,6 +542,7 @@ static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc, } static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = { + .mode_fixup = ltdc_crtc_mode_fixup, .mode_set_nofb = ltdc_crtc_mode_set_nofb, .atomic_flush = ltdc_crtc_atomic_flush, .atomic_enable = ltdc_crtc_atomic_enable, |