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Groups > linux.kernel > #1741979
| From | Chen-Yu Tsai <wens@csie.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v3 07/14] drm/sun4i: hdmi: Allow using second PLL as TMDS clk parent |
| Date | 2017-09-29 10:30 +0200 |
| Message-ID | <uuYQj-3Ke-35@gated-at.bofh.it> (permalink) |
| References | <uuYQi-3Ke-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On SoCs with two display pipelines, it is possible that the two
pipelines are active at the same time, with potentially incompatible
dot clocks.
Let the HDMI encoder's TMDS clock go through all of its parents when
calculating possible clock rates. This allows usage of the second video
PLL as its parent.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c | 53 ++++++++++++++++-------------
1 file changed, 29 insertions(+), 24 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c b/drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c
index 5cf2527bffc8..e8d4c311b80d 100644
--- a/drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c
+++ b/drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c
@@ -67,11 +67,11 @@ static unsigned long sun4i_tmds_calc_divider(unsigned long rate,
static int sun4i_tmds_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
- struct clk_hw *parent;
+ struct clk_hw *parent = NULL;
unsigned long best_parent = 0;
unsigned long rate = req->rate;
int best_div = 1, best_half = 1;
- int i, j;
+ int i, j, p;
/*
* We only consider PLL3, since the TCON is very likely to be
@@ -79,32 +79,37 @@ static int sun4i_tmds_determine_rate(struct clk_hw *hw,
* clock, so we should not need to do anything.
*/
- parent = clk_hw_get_parent_by_index(hw, 0);
- if (!parent)
- return -EINVAL;
-
- for (i = 1; i < 3; i++) {
- for (j = 1; j < 16; j++) {
- unsigned long ideal = rate * i * j;
- unsigned long rounded;
-
- rounded = clk_hw_round_rate(parent, ideal);
-
- if (rounded == ideal) {
- best_parent = rounded;
- best_half = i;
- best_div = j;
- goto out;
- }
-
- if (abs(rate - rounded / i) <
- abs(rate - best_parent / best_div)) {
- best_parent = rounded;
- best_div = i;
+ for (p = 0; p < clk_hw_get_num_parents(hw); p++) {
+ parent = clk_hw_get_parent_by_index(hw, p);
+ if (!parent)
+ continue;
+
+ for (i = 1; i < 3; i++) {
+ for (j = 1; j < 16; j++) {
+ unsigned long ideal = rate * i * j;
+ unsigned long rounded;
+
+ rounded = clk_hw_round_rate(parent, ideal);
+
+ if (rounded == ideal) {
+ best_parent = rounded;
+ best_half = i;
+ best_div = j;
+ goto out;
+ }
+
+ if (abs(rate - rounded / i) <
+ abs(rate - best_parent / best_div)) {
+ best_parent = rounded;
+ best_div = i;
+ }
}
}
}
+ if (!parent)
+ return -EINVAL;
+
out:
req->rate = best_parent / best_half / best_div;
req->best_parent_rate = best_parent;
--
2.14.2
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[PATCH v3 00/14] drm/sun4i: hdmi: Support HDMI controller on A31 Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 11/14] drm/sun4i: hdmi: Add A31 specific DDC register definitions Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 06/14] drm/sun4i: hdmi: create a regmap for later use Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 10/14] drm/sun4i: hdmi: Add support for controller hardware variants Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 07/14] drm/sun4i: hdmi: Allow using second PLL as TMDS clk parent Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 05/14] drm/sun4i: hdmi: Disable clks in bind function error path and unbind function Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 03/14] drm/sun4i: tcon: Add variant callback for TCON output muxing Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
Re: [PATCH v3 03/14] drm/sun4i: tcon: Add variant callback for TCON output muxing Maxime Ripard <maxime.ripard@free-electrons.com> - 2017-09-29 12:20 +0200
Re: [PATCH v3 03/14] drm/sun4i: tcon: Add variant callback for TCON output muxing Chen-Yu Tsai <wens@csie.org> - 2017-10-02 15:10 +0200
[PATCH v3 14/14] ARM: dts: sun6i: Enable HDMI support on some A31/A31s devices Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
[PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Chen-Yu Tsai <wens@csie.org> - 2017-09-29 10:30 +0200
Re: [PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Chen-Yu Tsai <wens@csie.org> - 2017-09-29 12:30 +0200
Re: [linux-sunxi] Re: [PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Julian Calaby <julian.calaby@gmail.com> - 2017-09-30 07:40 +0200
Re: [linux-sunxi] Re: [PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Chen-Yu Tsai <wens@csie.org> - 2017-09-30 08:00 +0200
Re: [linux-sunxi] Re: [PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Julian Calaby <julian.calaby@gmail.com> - 2017-09-30 08:30 +0200
Re: [linux-sunxi] Re: [PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Chen-Yu Tsai <wens@csie.org> - 2017-10-02 09:20 +0200
Re: [PATCH v3 04/14] drm/sun4i: tcon: Add support for demuxing TCON output on A31 Maxime Ripard <maxime.ripard@free-electrons.com> - 2017-09-29 12:30 +0200
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