+LTS/SOPINE Clusterboard, U-Boot, PL7 LED - Printable Version +- PINE64 (https://forum.pine64.org) +-- Forum: PINE A64(+) (https://forum.pine64.org/forumdisplay.php?fid=4) +--- Forum: Pine A64 Hardware, Accessories and POT (https://forum.pine64.org/forumdisplay.php?fid=32) +---- Forum: Pi2, Euler and Exp GPIO Ports (https://forum.pine64.org/forumdisplay.php?fid=34) +---- Thread: +LTS/SOPINE Clusterboard, U-Boot, PL7 LED (/showthread.php?tid=13359) |
Clusterboard, U-Boot, PL7 LED - Pine - 03-09-2021 Greetings, U-Boot has a board-specific method with signature Code: void show_boot_progress(int val); Various stages of U-Boot SPL and full U-Boot call this method with a known int to signal the current boot stage. I would like to activate PL7 on the SOPINE clusterboard which has an LED attached on certain checkpoints in booting. My question is, does anyone have experience with low-level GPIO registers/memory and knows how to achieve this? We can't use syntactic sugar like the following Code: gpio_direction_output(PL7_GPIO, 1); because the GPIO and DM (driver model) systems are not initialized at power-on yet (and I encounter an infinite loop deep in U-Boot trying to enumerate non-initialized hardware). I understand the pin number for PL7 is 359 from ([L - A] * 32) + 7. A solution using one of Code: writel(...); or would be a probable goal. Any ideas? |