linker: __data_region_start equal to __data_start #38817
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Fixes: zephyrproject-rtos#38591, zephyrproject-rtos#38207, zephyrproject-rtos#37861 The commit 65a2de8 aligned the data linker symbol for sections and regions. The data region symbol start has been placed outside the sections thus being defined as the address of the region before alignment of the first section in the data region, usually the `datas` section. The symbol defining the start address of the data section is after section alignment. In most cases the address of the data region start and datas section start will be identical, but not always. The data region symbol is a new linker symbol and existing code has been depending on the old data section start symbol. Thus, the update to the use of the data region start symbol instead of data ram start symbol thus results in a different address when the section is aligned to a different address. To ensure the original behavior in all cases, the data region start address is now moved inside the data section. Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
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Two additional commits targeted the ld linker script generator has been added to ensure the data and text region start symbol addresses are defined identical to using the ld template files. |
The root cause of zephyrproject-rtos#38591 was region symbols being placed before the section description for data region. Some region start symbols are placed before section description, other region start symbols are placed inside the first section in the region and thus identical to the sections own first symbol. To support both schemes with the linker generator, a new `SYMBOL SECTION` argument has been added to the zephyr_linker_group() function. The ld_script.cmake linker script generator has been updated to support the new argument so that generated ld linker script has identical behavior to the templated ld linker scripts. Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
The root cause of zephyrproject-rtos#38591 was region symbols being placed before the section description for data region. To support both schemes with the linker generator, a new `SYMBOL SECTION` argument has been added to the zephyr_linker_group() function. This commit updates the arm/linker.cmake CMake linker file to use the new `SYMBOL SECTION` argument for the data region group and text region group so that those two groups now behave identical to the behavior when using the cortex_m linker.ld template. Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
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Fixes: #38591, #38207, #37861
The commit 65a2de8 aligned the data
linker symbol for sections and regions.
The data region symbol start has been placed outside the sections thus
being defined as the address of the region before alignment of the first
section in the data region, usually the
datassection.The symbol defining the start address of the data section is after
section alignment.
In most cases the address of the data region start and datas section
start will be identical, but not always.
The data region symbol is a new linker symbol and existing code has
been depending on the old data section start symbol.
Thus, the update to the use of the data region start symbol instead of
data ram start symbol thus results in a different address when the
section is aligned to a different address.
To ensure the original behavior in all cases, the data region start
address is now moved inside the data section.
Signed-off-by: Torsten Rasmussen Torsten.Rasmussen@nordicsemi.no
DNM to allow time to examine the ld linker script generator for possible related fixup.