[BACKPORT] arch/arm/stm32: set F412 SRAM1_END to 256KiB - #406
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The F412 has 256KiB of system SRAM at 0x20000000 and no CCM. The F2/F4 heap map had no F412 entry, so it used the 128KiB default at 0x20020000 and left the upper half unused. Signed-off-by: Jacob Dahl <dahl.jakejacob@gmail.com> (cherry picked from commit 65d0b3f) Backport note: this tree still has stm32_allocateheap.c under arch/arm/src/stm32; upstream moved the F2/F4 heap map to arch/arm/src/common/stm32/stm32_allocateheap_m3m4_v1.c.
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Picks up PX4/NuttX#406, which sets SRAM1_END to 0x20040000 for the F412. The gitlink is the 10.3 tip, so this also carries PX4/NuttX#401. Signed-off-by: Jacob Dahl <dahl.jakejacob@gmail.com>
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Summary
Backport of apache/nuttx#20039, now merged upstream as 65d0b3f.
Give STM32F412 the 256 KiB of system SRAM it actually has. The F2/F4 heap map had no F412 entry, so
SRAM1_ENDwas the 128 KiB default.Problem
Every F412 (CE/CG/VG/ZG) has 256 KiB at
0x20000000and no CCM.stm32_allocateheap.clisted F401/F410/F427/F429/F446/F469 and dumped F412 into the 128 KiBelse, soup_allocate_heap()ended at0x20020000.Solution
Set
SRAM1_ENDto0x20040000whenCONFIG_STM32_STM32F412is selected.12.12 carry is #407. PX4-Autopilot gitlink and 256K linker scripts are PX4/PX4-Autopilot#28498, stacked on #28456.