The previous wording "top of PSRAM" was ambiguous: the carve-out is
actually mapped at the highest physical addresses of PSRAM (after the
rodata, text, and main heap mappings). Update the Kconfig help text for
SPIRAM_ENC_EXEMPT and SPIRAM_ENC_EXEMPT_SIZE, the External RAM
documentation, and the internal layout comment to say "upper end of PSRAM
(highest physical addresses)" instead.
Extends the External RAM encryption section to describe
CONFIG_SPIRAM_ENC_EXEMPT and the MALLOC_CAP_SPIRAM_NO_ENC heap
capability, including a security warning and a typical DMA-alignment
use case. Mirrors the change in zh_CN.
Adds CONFIG_SPIRAM_ENC_EXEMPT, available on chips that support per-page
PSRAM encryption configuration (esp32c5, esp32c61, esp32p4). When
enabled, esp_psram carves CONFIG_SPIRAM_ENC_EXEMPT_SIZE off the top of
PSRAM and maps it via the new mmu_hal_map_region_no_enc() helper, which
writes MMU entries without the SENSITIVE bit. The region is registered
as a separate heap pool reachable only through the new
MALLOC_CAP_SPIRAM_NO_ENC capability bit, so default SPIRAM allocations
cannot accidentally land there.
PSRAM encryption imposes alignment constraints that some DMA engines
(e.g. 2D-DMA) cannot satisfy. This option lets such workloads place
their buffers in unencrypted PSRAM while keeping the rest of PSRAM
(and flash) encrypted. Default disabled; security implications are
documented in the Kconfig help text.
Clarify that MALLOC_CAP_DEFAULT describes a memory capability
rather than the malloc() placement policy, so PSRAM-backed
capability allocations are documented correctly when malloc()
remains internal-only by default.
Closes https://github.com/espressif/esp-idf/issues/18391
Made-with: Cursor
This reverts earlier commit d2858847 and thereby making SPIRAM_USE_MEMMAP
available for all targets.
This config option has no direct usage but just avoids adding the PSRAM
to heap but still keeps it memory mapped.
Closes https://github.com/espressif/esp-idf/issues/17764
wuzhenghui
Mahavir Jain
Marius Vikhammer
harshal.patil
wangtao@espressif.com
Chen Jichang
muhaidong
Armando