From feca57ffa9c5a92186409569f849c246319047f4 Mon Sep 17 00:00:00 2001 From: Gustavo Henrique Nihei Date: Wed, 13 Jul 2022 10:08:16 -0300 Subject: [PATCH] esp32-devkitc: Add knsh configuration to the Documentation page Signed-off-by: Gustavo Henrique Nihei --- .../esp32/boards/esp32-devkitc/index.rst | 22 +++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/Documentation/platforms/xtensa/esp32/boards/esp32-devkitc/index.rst b/Documentation/platforms/xtensa/esp32/boards/esp32-devkitc/index.rst index a5d09ef0ff..db01f6e0b2 100644 --- a/Documentation/platforms/xtensa/esp32/boards/esp32-devkitc/index.rst +++ b/Documentation/platforms/xtensa/esp32/boards/esp32-devkitc/index.rst @@ -115,6 +115,28 @@ nsh Basic NuttShell configuration (console enabled in UART0, exposed via USB connection by means of CP2102 converter, at 115200 bps). +knsh +---- + +This is identical to the nsh configuration except that (1) NuttX +is built as PROTECTED mode, monolithic module and the user applications +are built separately and, as a consequence, (2) some features that are +only available in the FLAT build are disabled. + +Protected Mode support for ESP32 relies on the PID Controller peripheral +for implementing isolation between Kernel and Userspace. + +By working together with the MMU and Static MPUs of the ESP32, the PID +Controller is able to restrict the application access to peripherals, on-chip +memories (Internal ROM and Internal SRAM) and off-chip memories (External +Flash and PSRAM). + +.. warning:: + * The PID Controller driver is in **EXPERIMENTAL** state, so please + consider the Protected Mode feature for ESP32 a **Proof-of-Concept**. + * The PID Controller **does not** prevent the application from accessing + CPU System Registers. + wapi ----