Re: [PATCH v2 0/7] imx-drm: ipuv3-crtc: Implement mode_fixup

From: Philipp Zabel
Date: Fri Jan 23 2015 - 11:18:37 EST


Am Freitag, den 23.01.2015, 13:06 -0200 schrieb Fabio Estevam:
> On Fri, Jan 23, 2015 at 12:56 AM, Liu Ying <Ying.Liu@xxxxxxxxxxxxx> wrote:
> > Hi,
> >
> > It looks that the below commit makes my Hannstar XGA LVDS panel stop working
> > on the i.MX6DL SabreSD board. Any idea?
>
> Yes, with eb10d6355532def3a ("mx-drm: encoder prepare/mode_set must
> use adjusted mode") applied
> the DI clock is 0:

My bad, the problem is we are misusing encoder_prepare to enable the
display interface clock needed for the following crtc mode set.

What we really want is to use is adjusted_mode given to
encoder_funcs->mode_set, before the clock is enabled by
crtc_funcs->commit.

How about this patch:

-----8<-----
diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c
index abceb3d..99fe4bb 100644
--- a/drivers/gpu/drm/imx/imx-ldb.c
+++ b/drivers/gpu/drm/imx/imx-ldb.c
@@ -193,22 +193,8 @@ static void imx_ldb_encoder_prepare(struct drm_encoder *encoder)
{
struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
struct imx_ldb *ldb = imx_ldb_ch->ldb;
- struct drm_display_mode *mode = &encoder->crtc->hwmode;
u32 pixel_fmt;
- unsigned long serial_clk;
- unsigned long di_clk = mode->clock * 1000;
- int mux = imx_ldb_get_mux_id(imx_ldb_ch);

- if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
- /* dual channel LVDS mode */
- serial_clk = 3500UL * mode->clock;
- imx_ldb_set_clock(ldb, mux, 0, serial_clk, di_clk);
- imx_ldb_set_clock(ldb, mux, 1, serial_clk, di_clk);
- } else {
- serial_clk = 7000UL * mode->clock;
- imx_ldb_set_clock(ldb, mux, imx_ldb_ch->chno, serial_clk,
- di_clk);
- }

switch (imx_ldb_ch->chno) {
case 0:
@@ -281,6 +267,9 @@ static void imx_ldb_encoder_mode_set(struct drm_encoder *encoder,
struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
struct imx_ldb *ldb = imx_ldb_ch->ldb;
int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
+ unsigned long serial_clk;
+ unsigned long di_clk = mode->clock * 1000;
+ int mux = imx_ldb_get_mux_id(imx_ldb_ch);

if (mode->clock > 170000) {
dev_warn(ldb->dev,
@@ -291,6 +280,16 @@ static void imx_ldb_encoder_mode_set(struct drm_encoder *encoder,
"%s: mode exceeds 85 MHz pixel clock\n", __func__);
}

+ if (dual) {
+ serial_clk = 3500UL * mode->clock;
+ imx_ldb_set_clock(ldb, mux, 0, serial_clk, di_clk);
+ imx_ldb_set_clock(ldb, mux, 1, serial_clk, di_clk);
+ } else {
+ serial_clk = 7000UL * mode->clock;
+ imx_ldb_set_clock(ldb, mux, imx_ldb_ch->chno, serial_clk,
+ di_clk);
+ }
+
/* FIXME - assumes straight connections DI0 --> CH0, DI1 --> CH1 */
if (imx_ldb_ch == &ldb->channel[0]) {
if (mode->flags & DRM_MODE_FLAG_NVSYNC)
--
2.1.4
----->8-----

regards
Philipp

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/