STM32CubeMX generates wrong RAM size for STM32H745BITx

When using STM32CubeMX v6.0.1 to generate a project for dual-core STM32H745BIT6 MCU the resulting linker files for CM4 and CM7 show the following memory structures:

CM7

MEMORY
{
FLASH (rx) : ORIGIN = 0x08000000, LENGTH = 1024K
RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 128K
ITCMRAM (xrw) : ORIGIN = 0x00000000, LENGTH = 64K
}

CM4

MEMORY
{
FLASH (rx) : ORIGIN = 0x08100000, LENGTH = 1024K
RAM (xrw) : ORIGIN = 0x10000000, LENGTH = 288K
}

The Flash sizes seems to be correct, however the RAM size (128K + 288K) is way too low from the 1MByte which STM32H745BI is supposed to have as shown in the table below.

As Clive1 noted in another thread (https://community.st.com/s/question/0D50X0000BZHcaiSQD/linker-script-files-generated-by-stm32cubeide-dont-use-entire-ram-for-stm32h745) apart from adding additional lines in the linker memory structure one needs to also change the startup.s files.

Still to avoid improper changes to startup.s files it would be very helpful to have a sample startup.s example where one can see the changes which needs to be made to workaround the wrongly generated setup.