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authorYannick Fertre <yannick.fertre@st.com>2018-06-29 13:22:22 +0200
committerBenjamin Gaignard <benjamin.gaignard@linaro.org>2018-07-06 10:15:36 +0200
commit7868e5079228b4c07cf61b5ad5d35af5c29f7375 (patch)
tree89a569279cc887faef8d68952e8c584a09471935 /drivers/gpu/drm/stm
parentdrm: print plane state normalized zpos value (diff)
downloadlinux-7868e5079228b4c07cf61b5ad5d35af5c29f7375.tar.xz
linux-7868e5079228b4c07cf61b5ad5d35af5c29f7375.zip
drm/stm: ltdc: filter mode pixel clock vs pad constraint
Filter the requested mode pixel clock frequency according to the pad maximum supported frequency. Signed-off-by: Yannick Fertre <yannick.fertre@st.com> Reviewed-by: Philippe Cornu <philippe.cornu@st.com> Tested-by: Philippe Cornu <philippe.cornu@st.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/1530271342-5532-1-git-send-email-yannick.fertre@st.com
Diffstat (limited to 'drivers/gpu/drm/stm')
-rw-r--r--drivers/gpu/drm/stm/ltdc.c16
-rw-r--r--drivers/gpu/drm/stm/ltdc.h1
2 files changed, 13 insertions, 4 deletions
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index d997a6014d6c..f1f37336a57a 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -457,6 +457,14 @@ ltdc_crtc_mode_valid(struct drm_crtc *crtc,
int target_max = target + CLK_TOLERANCE_HZ;
int result;
+ result = clk_round_rate(ldev->pixel_clk, target);
+
+ DRM_DEBUG_DRIVER("clk rate target %d, available %d\n", target, result);
+
+ /* Filter modes according to the max frequency supported by the pads */
+ if (result > ldev->caps.pad_max_freq_hz)
+ return MODE_CLOCK_HIGH;
+
/*
* Accept all "preferred" modes:
* - this is important for panels because panel clock tolerances are
@@ -468,10 +476,6 @@ ltdc_crtc_mode_valid(struct drm_crtc *crtc,
if (mode->type & DRM_MODE_TYPE_PREFERRED)
return MODE_OK;
- result = clk_round_rate(ldev->pixel_clk, target);
-
- DRM_DEBUG_DRIVER("clk rate target %d, available %d\n", target, result);
-
/*
* Filter modes according to the clock value, particularly useful for
* hdmi modes that require precise pixel clocks.
@@ -991,11 +995,15 @@ static int ltdc_get_caps(struct drm_device *ddev)
* does not work on 2nd layer.
*/
ldev->caps.non_alpha_only_l1 = true;
+ ldev->caps.pad_max_freq_hz = 90000000;
+ if (ldev->caps.hw_version == HWVER_10200)
+ ldev->caps.pad_max_freq_hz = 65000000;
break;
case HWVER_20101:
ldev->caps.reg_ofs = REG_OFS_4;
ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
ldev->caps.non_alpha_only_l1 = false;
+ ldev->caps.pad_max_freq_hz = 150000000;
break;
default:
return -ENODEV;
diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
index 1e16d6afb0d2..d5afb8960867 100644
--- a/drivers/gpu/drm/stm/ltdc.h
+++ b/drivers/gpu/drm/stm/ltdc.h
@@ -18,6 +18,7 @@ struct ltdc_caps {
u32 bus_width; /* bus width (32 or 64 bits) */
const u32 *pix_fmt_hw; /* supported pixel formats */
bool non_alpha_only_l1; /* non-native no-alpha formats on layer 1 */
+ int pad_max_freq_hz; /* max frequency supported by pad */
};
#define LTDC_MAX_LAYER 4