Skip to content

LCD-7: 64-byte data cache lines and a 32 KB instruction cache for LVGL #17

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
bdbarnett merged 1 commit into from
Sep 25, 2026
Merged

LCD-7: 64-byte data cache lines and a 32 KB instruction cache for LVGL #17

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 11 additions & 0 deletions boards/esp32/WAVESHARE_ESP32_S3_TOUCH_LCD_7/sdkconfig.lcd7
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -26,3 +26,14 @@ CONFIG_LWIP_TCP_RECVMBOX_SIZE=16
# kept the UI thread 54 % busy while idle and starved every other Python
# thread, and 2-5 ms native waits rounded down to zero ticks.
CONFIG_FREERTOS_HZ=1000

# Caches sized for LVGL. Its code runs from flash and its objects and
# framebuffers live in PSRAM, which the RGB scanout is streaming from at the
# same time; with the port's 16 KB instruction cache and 32-byte lines every
# LVGL call ran 5-10x slower than its code. Measured on the remote's UI
# (2026-09-25): 64-byte lines took a full-screen redraw from 176 to 146 ms;
# a 32 KB instruction cache then took a list row from 66 to 44 ms and the
# redraw to 117 ms. It costs 16 KB of internal RAM (DMA-capable free 64 ->
# 48 KB). A 64 KB data cache (rows 30 ms) would leave ~13 KB, too little.
CONFIG_ESP32S3_DATA_CACHE_LINE_64B=y
CONFIG_ESP32S3_INSTRUCTION_CACHE_32KB=y