We are in the process of upgrading our kernel from version 4.14 to 5.15 for our arm-based i.MX 6ULL Single-Core Processor with Arm® Cortex®-A7 Core. We've encountered some issues during the compilation process and have a few queries regarding certain changes in the kernel configuration and device tree handling.
Below are the issues we're currently facing along with our queries:
1. Undefined Reference of IMX_GPIO_NR Macro:
In our previous kernel version 4.14, the IMX_GPIO_NR macro was defined in the "arch/arm/mach-imx/hardware.h" file as follows:
/* There's an off-by-one between the gpio bank number and the gpiochip range e.g. GPIO_1_5 is gpio 5 under linux */
#define IMX_GPIO_NR(bank, nr) (((bank) - 1) * 32 + (nr))
However, during the compilation of kernel version 5.15, we encountered undefined references to this macro. Has there been a change in the definition or usage of IMX_GPIO_NR macro in kernel 5.15? Additionally, has the gpio_request mechanism changed in kernel 5.15 that could be impacting our usage of this macro for defining GPIO pins for our Wi-Fi/BT chip?
2. Missing Configuration Option SOC_IMX6ULL from arch/arm/mach-imx/Kconfig
We noticed that the configuration option "SOC_IMX6ULL" is not available in the file "arch/arm/mach-imx/Kconfig" for our i.MX 6ULL processor. As our processor type is i.MX 6ULL and its specific configurations are not present, can we safely use configurations meant for i.MX 6UL processors?
3. Inclusion of imx6ul.dtsi in imx6ull.dtsi
In the kernel version 4.14, the "imx6ull.dtsi" file included only imx6ull related files. However, in the 5.15 kernel, we observed that "imx6ull.dtsi" now includes "imx6ul.dtsi" file. Does this imply that kernel 5.15 does not fully support i.MX 6ULL series processors, or is it acceptable to use i.MX 6UL configurations for our i.MX 6ULL processor?
We would greatly appreciate your guidance and assistance in resolving these issues and clarifying our queries. Your expertise in NXP processors and kernel development would be invaluable to us in successfully upgrading our system.
@igorpadykov @wang @RITA
