The newest ESP32 can run Linux and it's getting close to a Raspberry Pi
Points and comments are a snapshot, not live.
Espressif's ESP32-S31 adds a real Sv32 MMU, gigabit Ethernet and USB host, letting Linux boot on what is still a microcontroller.
The ESP32-S31 pairs two 32-bit RISC-V cores at up to 320 MHz plus a 40 MHz low-power core with a 1000 Mbps Ethernet MAC over RGMII, a USB 2.0 High-Speed OTG host controller, dual SDIO slots, a DVP camera interface, a parallel RGB LCD controller, and Wi-Fi 6, Bluetooth 5.4 and 802.15.4 radios. It carries 512 KB of on-chip SRAM, up to 256 MB flash and up to 64 MB PSRAM over a dedicated 250 MHz 8-bit DDR interface.
The key change is the MMU: Espressif now implements RISC-V Sv32 two-level page-table translation with Machine, Supervisor and User privilege modes, versus the simpler flash-and-PSRAM mapping it previously called an MMU. Espressif published a Buildroot and U-Boot Linux BSP in August, and community ports run Linux 6.18 and 7.1, one showing a console on an 800x480 LCD.
The downsides: at most 64 MB PSRAM and no DRAM controller, no GPU or NPU, and the datasheet is still version 0.5 and marked preliminary, listing 80 MHz PSRAM against Espressif's published 250 MHz.
What commenters are saying
Commenters focused on the Sv32 MMU as the enabler, with one noting it is a full 32-bit RISC-V MMU, not a partial one, and others seeing the S31 as a cheap emulation platform for retro consoles and even a 386, with a 486 plausible. Two camps formed over XDA's writing: one calling it AI-pumped and the author replying that it is human-written and that a heading was a typo from being sick. Others corrected technical framing, noting MCU versus SBC confusion and that the S31 has no MIPI CSI and an 8-bit PSRAM bus.