Consensus on the mailing lists is that panels shouldn't use a table of
init commands but should instead use init functions. We'll use the
same concepts as the recently introduced
mipi_dsi_generic_write_seq_multi() to make this clean/easy and also
not bloat the driver too much. Measuring before/after this change:
$ scripts/bloat-o-meter \
.../before/panel-innolux-p079zca.ko \
.../after/panel-innolux-p079zca.ko
add/remove: 3/2 grow/shrink: 0/1 up/down: 2356/-1944 (412)
Function old new delta
innolux_p097pfg_init - 1772 +1772
innolux_p097pfg_init.d - 480 +480
innolux_panel_write_multi - 104 +104
innolux_panel_prepare 412 308 -104
.compoundliteral 480 - -480
innolux_p097pfg_init_cmds 1360 - -1360
Total: Before=5802, After=6214, chg +7.10%
Note that, unlike some other drivers, we actually make this panel
driver _bigger_ by using the new functions. This is because the
innolux-p079zca panel driver didn't have as complex of a table and
thus the old table was more efficient than the code. The bloat is
still not giant (only 412 bytes).
Also note that we can't direclty use
mipi_dsi_generic_write_seq_multi() here because we need to deal with
the crazy "nop" that this driver sends after all commands. This means
that we have to write code that is "inspired" by the new macros.
Since we're touching all the tables, let's also convert hex numbers to
lower case as per kernel conventions.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240514102056.v5.9.I947e28c81f9ef7dcd3add6e193be72d6f8ea086f@changeid
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240514102056.v5.9.I947e28c81f9ef7dcd3add6e193be72d6f8ea086f@changeid
Consensus on the mailing lists is that panels shouldn't use a table of
init commands but should instead use init functions. With the recently
introduced mipi_dsi_dcs_write_seq_multi() this is not only clean/easy
but also saves space. Measuring before/after this change:
$ scripts/bloat-o-meter \
.../before/panel-ilitek-ili9882t.ko \
.../after/panel-ilitek-ili9882t.ko
add/remove: 3/2 grow/shrink: 0/2 up/down: 6834/-8177 (-1343)
Function old new delta
starry_ili9882t_init - 6152 +6152
starry_ili9882t_init.d - 678 +678
ili9882t_disable.d - 4 +4
ili9882t_disable 260 228 -32
ili9882t_prepare 540 396 -144
.compoundliteral 681 - -681
starry_ili9882t_init_cmd 7320 - -7320
Total: Before=11928, After=10585, chg -11.26%
Let's do the conversion.
Since we're touching all the tables, let's also convert hex numbers to
lower case as per kernel conventions.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240514102056.v5.8.I407b977f9508573103491df549dfaffc3688db13@changeid
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240514102056.v5.8.I407b977f9508573103491df549dfaffc3688db13@changeid
The current mipi_dsi_*_write_seq() macros are non-intutitive because
they contain a hidden "return" statement that will return out of the
_caller_ of the macro. Let's mark them as deprecated and instead
introduce some new macros that are more intuitive.
These new macros are less optimal when an error occurs but should
behave more optimally when there is no error. Specifically these new
macros cause smaller code to get generated and the code size savings
(less to fetch from RAM, less cache space used, less RAM used) are
important. Since the error case isn't something we need to optimize
for and these new macros are easier to understand and more flexible,
they should be used.
After converting to use these new functions, one example shows some
nice savings while also being easier to understand.
$ scripts/bloat-o-meter \
...after/panel-novatek-nt36672e.ko \
...ctx/panel-novatek-nt36672e.ko
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-988 (-988)
Function old new delta
nt36672e_1080x2408_60hz_init 6236 5248 -988
Total: Before=10651, After=9663, chg -9.28%
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240514102056.v5.5.Ie94246c30fe95101e0e26dd5f96e976dbeb8f242@changeid
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240514102056.v5.5.Ie94246c30fe95101e0e26dd5f96e976dbeb8f242@changeid
Through a cooperative effort between Hsin-Yi Wang and Dmitry
Baryshkov, we have realized the dev_err() in the
mipi_dsi_*_write_seq() macros was causing quite a bit of bloat to the
kernel. Let's hoist this call into drm_mipi_dsi.c by adding a "chatty"
version of the functions that includes the print. While doing this,
add a bit more comments to these macros making it clear that they
print errors and also that they return out of _the caller's_ function.
Without any changes to clients this gives a nice savings. Specifically
the macro was inlined and thus the error report call was inlined into
every call to mipi_dsi_dcs_write_seq() and
mipi_dsi_generic_write_seq(). By using a call to a "chatty" function,
the usage is reduced to one call in the chatty function and a function
call at the invoking site.
Building with my build system shows one example:
$ scripts/bloat-o-meter \
.../before/panel-novatek-nt36672e.ko \
.../after/panel-novatek-nt36672e.ko
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-4404 (-4404)
Function old new delta
nt36672e_1080x2408_60hz_init 10640 6236 -4404
Total: Before=15055, After=10651, chg -29.25%
Note that given the change in location of the print it's harder to
include the "cmd" in the printout for mipi_dsi_dcs_write_seq() since,
theoretically, someone could call the new chatty function with a
zero-size array and it would be illegal to dereference data[0].
There's a printk format to print the whole buffer and this is probably
more useful for debugging anyway. Given that we're doing this for
mipi_dsi_dcs_write_seq(), let's also print the buffer for
mipi_dsi_generic_write_seq() in the error case.
It should be noted that the current consensus of DRM folks is that the
mipi_dsi_*_write_seq() should be deprecated due to the non-intuitive
return behavior. A future patch will formally mark them as deprecated
and provide an alternative.
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240514102056.v5.4.Id15fae80582bc74a0d4f1338987fa375738f45b9@changeid
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240514102056.v5.4.Id15fae80582bc74a0d4f1338987fa375738f45b9@changeid
The checks on the existence of bridge->encoder in the implementation of
drm_bridge_funcs::attach() is not necessary, as it has already been checked
in the drm_bridge_attach() function call by previous bridge or KMS driver.
The drm_bridge_attach() will quit with a negative error code returned if
it fails for some reasons, hence, it is guaranteed that the .encoder member
of the drm_bridge instance is not NULL when various bridge attach functions
are called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-13-sui.jingfeng@linux.dev
The checks on the existence of bridge->encoder in the implementation of
drm_bridge_funcs::attach() is not necessary, as it has already been checked
in the drm_bridge_attach() function call by previous bridge or KMS driver.
The drm_bridge_attach() will quit with a negative error code returned if
it fails for some reasons, hence, it is guaranteed that the .encoder member
of the drm_bridge instance is not NULL when various i.MX specific bridge
attach functions are called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-12-sui.jingfeng@linux.dev
In the lt9611uxc_connector_init() function, the check on the existence
of bridge->encoder is not necessary, as it has already been checked in
the drm_bridge_attach() function. And the check on the drm bridge core
happens before check in the implementation. Hence, it is guaranteed that
the .encoder member of the struct drm_bridge is not NULL when
lt9611uxc_connector_init() function get called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-11-sui.jingfeng@linux.dev
In the dw_mipi_dsi_bridge_attach() function, the check on the existence
of bridge->encoder is not necessary, as it has already been checked in
the drm_bridge_attach() function invocked by previous bridge or KMS driver.
The previous drm_bridge_attach() will quit with a negative error code
returned if it fails for some reasons, hence, it is guaranteed that the
.encoder member of the struct drm_bridge is not NULL when
dw_mipi_dsi_bridge_attach() function gets called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-10-sui.jingfeng@linux.dev
In the ge_b850v3_lvds_create_connector function, the check on the existence
of bridge->encoder is not necessary, as it has already been checked in the
drm_bridge_attach() function called by upstream bridge or driver. Hence, it
is guaranteed that the .encoder member of the drm_bridge instance is not
NULL when cdns_mhdp_connector_init() function get called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-9-sui.jingfeng@linux.dev
In the cdns_mhdp_connector_init() function, the check on the existence
of bridge->encoder is not necessary, as it has already been checked in
the drm_bridge_attach() function. As the cdns_mhdp_connector_init() is
only called by cdns_mhdp_attach(), it is guaranteed that the .encoder
member of the struct drm_bridge is not NULL when cdns_mhdp_attach() gets
called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-8-sui.jingfeng@linux.dev
In the adv7511_connector_init() function, the check on the existence of
bridge->encoder is not necessary. As it has already been checked in the
drm_bridge_attach() which happens prior to the adv7511_bridge_attach()
get called. Also note that the adv7511_connector_init() is only called by
adv7511_bridge_attach(). Hence, it is guaranteed that the .encoder member
of the drm_bridge instance is not NULL when adv7511_connector_init() get
called.
Remove the redundant checking codes "if (!bridge->encoder) { ... }".
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513153109.46786-7-sui.jingfeng@linux.dev
