Adapt kernel config to disable framebuffer console

BCS 746-000063

Norman Stetter authored 4 years ago and Clemens Terasa committed 4 years ago

The Garz & Fricke gitlab has been restructured, change fetch URL of
the gfxml2dto as well as the README.md documentation.

Rename the linux kernel repository to linux-guf.
Switch to SRCREV="${AUTOREV}" for the kernel development.

The team decision is to rename the linux kernel repository from
linux-stable to linux-guf to show that it actually does not mirror the
linux-stable directly but uses it as a basis source for our Garz &
Fricke development.

This changes include renaming the recipe, adjusting the Gitlab URL and
renaming the PREFERRED_PROVIDER_virtual/kernel.

With this change we also want to use the bitbake AUTOREV feature to pull
the latest development kernel. Right now we do not have the release
method to pin the revision to a specific version.

To be able to use the externally built touch drivers we provide in the
BSP we need to add the touch drivers. This is done with the help of the
packagegroup-guf-touchdriver that combines all drivers.

Compared to Rocko the EDT driver was not ported: we want to use he
mainline one.

It is still unclear if we want to use the touchgpio helper driver. It
provides general functionality for the GPIO handling of teh drivers,
however this shall be part of the drivers.
Setting GPIO options may very well be possible by using the gpiod_*
interface instead of the legacy gpio kernel interface.

A minor mapping bug was fixed and the irq-gpio, reset-gpio and wake-gpio
parsing was introduced. This is currently only used by
rbtouch-eeti-exc3000-v00.xml however we will adapt the other touch
settings accordingly.

Use the mainline kernel driver instead.
This, however, also remove the touchgpio functionality form the driver.
It might be OK if the touchgpio driver is deprecated anyway.

Add a valid fall through comment to the switch fall though.
See https://lwn.net/Articles/794944/ why this is necessary since Linux
5.3.

Also replace the VLA (Variable Length Arrays) expression by adding a
constexpr max().
See https://stackoverflow.com/a/49481218 for a detailed explanation of
__is_constexpr() in the linux kernel used for max() and useful links.

The access_ok macro has changed and abolished the first parameter with
commit 96d4f267e40f9509e8a66e2b39e8b95655617693 (v5.0).
Thus change the  eetii2c driver accordingly and remove the first
parameter.

Replace deprecated functions vfs_read/vfs_write with
kernel_read/kernel_write.  Use the KERNEL_DS define instead of the
deprecated get_de() function.

Replace the deprecated do_gettimeofday() function call with the recent
ktime_get_real_ts64() function and move from struct timeval to struct
timespec64 to do this.

Fix a compiler error that complains about large frames by reducing the
stack size in the function ilitek_sensortest_write().

Replace the usage of the deprecated do_gettimeofday() function using
struct  timeval with the newer ktime_get_real_ts64() function using
timespec64. This makes it necessary to change the time difference
calculation as well.

Also replace the deprecated get_ds() function call with the recent
KERNEL_DS define.

Remove the FB_EARLY_EVENT_BLANK that was removed with Linux kernel
commit e7642f35851da14b78be7a38b0bb0d4068254859.

The compiler complained about a variable length array declaration.
It is no valid C90 and is considered "STUPID" by Linus Torvalds :)
https://lkml.org/lkml/2018/3/7/621

The function egalax_I2C_write is only called once with a fix value of
MAX_I2C_LEN and thus use this valie instead.

* Copied touch drivers from G&F Rocko
* Includes the drivers for several touches including
** atmel-mtx
** AUO pixcir
** EDT ft5x05 and ft5x06
** EETI EXC7200 (i2c)
** EETI EXC3000 (i2c) including 80H80
** Himax
** Ilitek 2118
** Ilitek 25xx
** SCX050000
** SIS
* Also includes touchgpio kernel module that generalizes the GPIO
handling
* Include a guf-kernel-module.inc include file

Somehow the Garz & Fricke specific PCF8563 driver rtc-pcf8563-guf was
not buildable.

On cause was a missing and unused config.h file. Remove this file from
the recipe.

Another error was due to the removal of the register resets in the
PCF8563 that should be prevented by the driver. However the buffer
variable is used later on so we cannot comment it out.

* Use known scheme: imx6guf for SAN*, imx6ullguf for NALLINO
* Machine overrides are now set directly in the corresponding machine
configs instead of relying on 'imx-base.inc' from meta-freescale
* Update README

Pull the latest kernel including an increase of the Backlight PWM
frequency. Together with the activated panel-dt and the previously added
gfxml2dto more then one display can be supported,

To convert the Garz & Fricke specific XML files to the more general
Device Tree overlay files a tool is needed.

This tool is called gfxml2dto.
It is capable of reading the G&F XML file (by default located in
/etc/shared/config.xml) and converting some of the parts to device tree
overlay blobs.

These blobs together with a base device tree can be used to generate a
system specific device tree. The base device tree needs to be created
including the symbols. (This is achieved by using the "-@" flag when
using the `dtc` tool.)

We currently have no versioning applied to gfxml2dto.

Add this gfxml2dto to the MACHINE_EXTRA_RRECOMMENDS to install it in
images using this machine layer.

The Flash-N-Go Boot bootloader propagates its version using ATAGS.
ATAGS, however, will be destroyed after bootup if an appended device tree
was found. Thus it needs to be saved to the device tree by the kernel
before.

Souch a kernel patch has been added and now get the FnGBoot info from
the device tree.

The Device Tree entry used for this is FnGBoot agnostic and was called
"atag-revision".

Pull in the ATAGS_REVISION propagation from git commit
adddc460e1f761b7c41ec171dd88d6db92faee47.

This will later enable the gfplatdetect module to parse the atag-revision
entry from teh Device Tree. This is used by the FnGBoot bootloader to
propagate its version.

Pull the latest kernel version fa7cf8de40b0695d856dab2a417bcb3c53620d36.
This adds support for the gfplatdetect module that needs some exported
symbols.

It also activates the gfplatdetect in the device tree.

With the gfplatdetect module it is possible for all Garz & Fricke
iMX6QDL platforms (San* platforms) to detect the board type, board
revision and more information form the so caled PFID GPIO pins.

Because of legacy we propagate this info to the `/proc/cpuinfo`.
Add the gfplatdetect module for all Garz & Fricke San* boards.

This commit establishes a working module and adds the real code to detect the
platform and to propagate the platform to the /proc/cpuinfo file.
The platform detection module is meant to replace the previous platform
detection code in the imx6 board file.

The kernel, however, needs some adaptions namely the exported symbols for
the system_rev, board_rev, fngboot_rev and macghine_name.
These are defined in arc/arm/kernel/setup.c and are meant to be
displayed via the /proc/cpuinfo file.

The other explicit exports are imx_get_soc_revision and a new function
mxc_get_cpu_type which returns the __mxc_cpu_type variable.

The main parts are taken from the previous implementation in the current
rocko G&F kernel and from the Flash-N-Go Boot board detection code.

Read the "pfid-gpios" from the device tree entry to get the correct
GPIOs. This prevents the need for gpio definitions in this driver.

Backup the previous information in case we want to unload the driver.
Do this mainly for the machine_name string to prevent a dangling
string pointer.

Add another new sysfs interface to read the board and board revision.
This might deprecate the /proc/cpuinfo part so that we do not have to
touch it in the future anymore.
And with teh sysfs we get a consistent method to propagate G&F specific
board information.

Right now only the imx6qdl (San*) platforms are supported. The imx6ull
devices (NALLINO) are not yet supported.

* fnginstallscript lives in the distro layer
* This way it may be still enabled in a machine specific way

* Allow usage of commandline from bootloader
* Adapt the default commandline:
** Remove earlyprintk, should be used for debug only

* Remove unused lines
* Added bootscript to machine essential rdepends
  This way the inclusion into the image and the recipe live in the same
  layer

We want to overlay the device tree in the install script. Thus we can
create a device specific device tree with the generic name
"devicetree.dtb".

This removes the neccessary pacthing of the boot.cfg.

However, currently we cannot load the devicetree with the bootloader and
thus append the device tree to the kernel at installation time and name
the resulting binary "linuximage".

Add the bootscript from current rocko commit
ad543879 with following modifications:
- Move imx6guf to san and imx6ullguf to nallino
- Remove the "inherit release" as the release is not supported right now

The bootscript recipe builds but does not output the correct script yet.

The variables IMAGE_BOOT_FILES and IMAGE_FSTYPES are less machine
dependent and are more distro options.

Thus move them to meta-guf-distro.

Also edit the README accordingly.

The ordinary kernel.bbclass should implement all necessary dependencies
needed to build the linux kernel.

I tried to remove the build dependencies and it worked for me, thus
remove the unneccessary dependencies.

Normally teh device tree blobs will be built without symbols like the
aliases that may be used like references.

However, the overlay method relies on the fact that the symbols are
present in the devcie tree to be overlayed. This can be eigther achieved
by using a textual representation of the devcie tree or by additional
symbols in the device tree blob.

Introduce the latter, so that we can use the device tree blob as overlay
basis.

* disable TIMER_CONTROL register TD[1:0] bit configuration in PCF8563 driver
  probe since we use that bits for bootselect

* Pull the rtc-pcf8563.c source from the kernel-tree at v5.4.23
 (bfe3046ecafdd71ba6932deebe2eb357048b7bfc)
* Remove the in-tree driver from the defconfig
* Add the module to the MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS for san* and
nallino platforms

- increased U-Boot boot delay to 3 seconds to be able to interrupt the bootloader properly with 'ESC' as configured

- add a first NALLINO configuration to allow U-Boot build ('bitbake u-boot')

- allow our linux-stable-5.4 kernel also to be build for NALLINO

- added U-Boot for NALLINO taken from GUF-Yocto-rocko-9.2.0-IMXULLGUF-bsp

- update to new kernel version
  - USB support
  - thernet support
  - audio support

- added documentation for running basic tests

- use new kernel version with all I2C devices present for testing on 400 kHz bus rate

- cleaned up machine config to be able to add more boards later

- use new kernel with SIS9255 touch support and updated kernel's defconfig