From c4e4fccc5d52d881afaac11d3353265ef4eccb8b Mon Sep 17 00:00:00 2001
From: Wayne Lin <Wayne.Lin@amd.com>
Date: Fri, 3 Jan 2020 13:50:01 +0800
Subject: [PATCH 1/3] drm/dp_mst: correct the shifting in DP_REMOTE_I2C_READ
[Why]
According to DP spec, it should shift left 4 digits for NO_STOP_BIT
in REMOTE_I2C_READ message. Not 5 digits.
In current code, NO_STOP_BIT is always set to zero which means I2C
master is always generating a I2C stop at the end of each I2C write
transaction while handling REMOTE_I2C_READ sideband message. This issue
might have the generated I2C signal not meeting the requirement. Take
random read in I2C for instance, I2C master should generate a repeat
start to start to read data after writing the read address. This issue
will cause the I2C master to generate a stop-start rather than a
re-start which is not expected in I2C random read.
[How]
Correct the shifting value of NO_STOP_BIT for DP_REMOTE_I2C_READ case in
drm_dp_encode_sideband_req().
Changes since v1:(https://patchwork.kernel.org/patch/11312667/)
* Add more descriptions in commit and cc to stable
Fixes: ad7f8a1f9ced ("drm/helper: add Displayport multi-stream helper (v0.6)")
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200103055001.10287-1-Wayne.Lin@amd.com
---
drivers/gpu/drm/drm_dp_mst_topology.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 273dd80fabf3c..644c72f9c5949 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -393,7 +393,7 @@ drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req,
memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
idx += req->u.i2c_read.transactions[i].num_bytes;
- buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
+ buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 4;
buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
idx++;
}
From 4396393fb96449c56423fb4b351f76e45a6bcaf6 Mon Sep 17 00:00:00 2001
From: Chen-Yu Tsai <wens@csie.org>
Date: Tue, 7 Jan 2020 15:01:13 +0800
Subject: [PATCH 2/3] drm/sun4i: tcon: Set RGB DCLK min. divider based on
hardware model
In commit 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK
to 1.") it was assumed that all TCON variants support a minimum divider
of 1 if only DCLK was used.
However, the oldest generation of hardware only supports minimum divider
of 4 if only DCLK is used. If a divider of 1 was used on this old
hardware, some scrolling artifact would appear. A divider of 2 seemed
OK, but a divider of 3 had artifacts as well.
Set the minimum divider when outputing to parallel RGB based on the
hardware model, with a minimum of 4 for the oldest (A10/A10s/A13/A20)
hardware, and a minimum of 1 for the rest. A value is not set for the
TCON variants lacking channel 0.
This fixes the scrolling artifacts seen on my A13 tablet.
Fixes: 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK to 1.")
Cc: <stable@vger.kernel.org> # 5.4.x
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107070113.28951-1-wens@kernel.org
---
drivers/gpu/drm/sun4i/sun4i_tcon.c | 15 ++++++++++++---
drivers/gpu/drm/sun4i/sun4i_tcon.h | 1 +
2 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 42651d737c55b..c81cdce6ed559 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -489,7 +489,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
WARN_ON(!tcon->quirks->has_channel_0);
- tcon->dclk_min_div = 1;
+ tcon->dclk_min_div = tcon->quirks->dclk_min_div;
tcon->dclk_max_div = 127;
sun4i_tcon0_mode_set_common(tcon, mode);
@@ -1426,12 +1426,14 @@ static int sun8i_r40_tcon_tv_set_mux(struct sun4i_tcon *tcon,
static const struct sun4i_tcon_quirks sun4i_a10_quirks = {
.has_channel_0 = true,
.has_channel_1 = true,
+ .dclk_min_div = 4,
.set_mux = sun4i_a10_tcon_set_mux,
};
static const struct sun4i_tcon_quirks sun5i_a13_quirks = {
.has_channel_0 = true,
.has_channel_1 = true,
+ .dclk_min_div = 4,
.set_mux = sun5i_a13_tcon_set_mux,
};
@@ -1440,6 +1442,7 @@ static const struct sun4i_tcon_quirks sun6i_a31_quirks = {
.has_channel_1 = true,
.has_lvds_alt = true,
.needs_de_be_mux = true,
+ .dclk_min_div = 1,
.set_mux = sun6i_tcon_set_mux,
};
@@ -1447,11 +1450,13 @@ static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
.has_channel_0 = true,
.has_channel_1 = true,
.needs_de_be_mux = true,
+ .dclk_min_div = 1,
};
static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
.has_channel_0 = true,
.has_channel_1 = true,
+ .dclk_min_div = 4,
/* Same display pipeline structure as A10 */
.set_mux = sun4i_a10_tcon_set_mux,
};
@@ -1459,11 +1464,13 @@ static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
.has_channel_0 = true,
.has_lvds_alt = true,
+ .dclk_min_div = 1,
};
static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = {
.supports_lvds = true,
.has_channel_0 = true,
+ .dclk_min_div = 1,
};
static const struct sun4i_tcon_quirks sun8i_a83t_tv_quirks = {
@@ -1477,11 +1484,13 @@ static const struct sun4i_tcon_quirks sun8i_r40_tv_quirks = {
static const struct sun4i_tcon_quirks sun8i_v3s_quirks = {
.has_channel_0 = true,
+ .dclk_min_div = 1,
};
static const struct sun4i_tcon_quirks sun9i_a80_tcon_lcd_quirks = {
- .has_channel_0 = true,
- .needs_edp_reset = true,
+ .has_channel_0 = true,
+ .needs_edp_reset = true,
+ .dclk_min_div = 1,
};
static const struct sun4i_tcon_quirks sun9i_a80_tcon_tv_quirks = {
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index f9f1fe80b206c..a62ec826ae71e 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -224,6 +224,7 @@ struct sun4i_tcon_quirks {
bool needs_de_be_mux; /* sun6i needs mux to select backend */
bool needs_edp_reset; /* a80 edp reset needed for tcon0 access */
bool supports_lvds; /* Does the TCON support an LVDS output? */
+ u8 dclk_min_div; /* minimum divider for TCON0 DCLK */
/* callback to handle tcon muxing options */
int (*set_mux)(struct sun4i_tcon *, const struct drm_encoder *);
From f30e27779d3031a092c2a177b7fb76adccc45241 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Mon, 30 Dec 2019 14:27:34 +0100
Subject: [PATCH 3/3] drm/fb-helper: Round up bits_per_pixel if possible
When userspace requests a video mode parameter value that is not
supported, frame buffer device drivers should round it up to a supported
value, if possible, instead of just rejecting it. This allows
applications to quickly scan for supported video modes.
Currently this rule is not followed for the number of bits per pixel,
causing e.g. "fbset -depth N" to fail, if N is smaller than the current
number of bits per pixel.
Fix this by returning an error only if bits per pixel is too large, and
setting it to the current value otherwise.
See also Documentation/fb/framebuffer.rst, Section 2 (Programmer's View
of /dev/fb*").
Fixes: 865afb11949e5bf4 ("drm/fb-helper: reject any changes to the fbdev")
Cc: stable@vger.kernel.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191230132734.4538-1-geert+renesas@glider.be
---
drivers/gpu/drm/drm_fb_helper.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 8ebeccdeed233..d8e8f3960f4db 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1283,7 +1283,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
* Changes struct fb_var_screeninfo are currently not pushed back
* to KMS, hence fail if different settings are requested.
*/
- if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
+ if (var->bits_per_pixel > fb->format->cpp[0] * 8 ||
var->xres > fb->width || var->yres > fb->height ||
var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
DRM_DEBUG("fb requested width/height/bpp can't fit in current fb "
@@ -1308,6 +1308,11 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
drm_fb_helper_fill_pixel_fmt(var, fb->format->depth);
}
+ /*
+ * Likewise, bits_per_pixel should be rounded up to a supported value.
+ */
+ var->bits_per_pixel = fb->format->cpp[0] * 8;
+
/*
* drm fbdev emulation doesn't support changing the pixel format at all,
* so reject all pixel format changing requests.