feat: make the memory footprint tunable and lower defaults to measured floors - #187
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CONFIG_SOFTSIM_STACK_SIZE replaces the hardcoded 10000, and the main-stack/ heap values move from overlay assignments to Kconfig defaults so an application prj.conf can override them. Values unchanged. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
nrf_softsim_init() eagerly allocated ~5 KB of heap the INIT handler already allocates on demand; APDU/RESET without a context now answer with an error. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
The R-APDU buffer and the PSA cipher scratch are only live inside one function each; as stack locals they stop costing 516 B of permanent RAM. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
The longest path in a provisioned profile is 20 chars; 100 mostly paid in storage-layer stack frames. The port sources now get the same define. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
The default case answered nothing, leaving the modem waiting forever on any command a future firmware adds. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
Measured RAM/flash budgets for the nRF9151 sample, where the module's static and heap bytes go, and how to measure before trimming a knob. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
On-target nRF9151-DK: heap peak 17856 B and softsim-thread HWM 2200 B across provisioning, attach and 12 re-attach cycles; defaults keep OTA headroom and margin (heap 24000, stack 6000). Signed-off-by: Benjamin Bruun <bb@onomondo.com>
Measured: TF-M uses ~40 KB; the only cut is one 8 KB SPU step, and the instance also serves the integrating application's PSA/ITS usage. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
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An application's own CONFIG_HEAP_MEM_POOL_SIZE beat the Kconfig default and tripped the floor assert. Declare HEAP_MEM_POOL_ADD_SIZE_SOFTSIM so the kernel rounds the effective pool up to it, and assert on the effective K_HEAP_MEM_POOL_SIZE. Signed-off-by: Benjamin Bruun <bb@onomondo.com>
Signed-off-by: Benjamin Bruun <bb@onomondo.com>
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The stack/heap requirements imposed on integrating apps become overridable Kconfig options, and the defaults drop to measured values: SoftSIM workqueue stack 10000 -> 6000 and heap (plus its build-assert floor) 30000 -> 24000, based on on-target measurement over provisioning, attach and 12 re-attach cycles (heap peak 17.9 KB, stack high-water 2.2 KB). Also defers the SIM context allocation to the modem INIT request, moves scratch buffers off .bss, sizes SS_STORAGE_PATH_MAX to real paths, and adds docs/memory.md with the measured budget.