Searched hist:"9 cc3fa1b8ae31c18fd3a6070b782b3384590523e" (Results 1 – 2 of 2) sorted by relevance
| /rk3399_ARM-atf/plat/rpi/common/ |
| H A D | rpi3_common.c | 9cc3fa1b8ae31c18fd3a6070b782b3384590523e Wed Mar 11 15:18:03 UTC 2020 Andre Przywara <andre.przywara@arm.com> rpi: console: Autodetect Mini-UART vs. PL011 configuration
The Raspberry Pi has two different UART devices pin-muxed to GPIO 14&15:
One ARM PL011 one and the 8250 compatible "Mini-UART".
A dtoverlay parameter in config.txt will tell the firmware to switch
between the two: it will setup the right clocks and will configure the
pinmuxes accordingly.
To autodetect the user's choice, we read the pinmux register and check
its setting: ALT5 (0x2) means the Mini-UART is used, ALT0 (0x4) points
to the PL011.
Based on that we select the UART driver to initialise.
This will allow console output in any case.
Change-Id: I620d3ce68de6c6576599f2a405636020e1fd1376
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
|
| /rk3399_ARM-atf/plat/rpi/rpi4/ |
| H A D | platform.mk | 9cc3fa1b8ae31c18fd3a6070b782b3384590523e Wed Mar 11 15:18:03 UTC 2020 Andre Przywara <andre.przywara@arm.com> rpi: console: Autodetect Mini-UART vs. PL011 configuration
The Raspberry Pi has two different UART devices pin-muxed to GPIO 14&15:
One ARM PL011 one and the 8250 compatible "Mini-UART".
A dtoverlay parameter in config.txt will tell the firmware to switch
between the two: it will setup the right clocks and will configure the
pinmuxes accordingly.
To autodetect the user's choice, we read the pinmux register and check
its setting: ALT5 (0x2) means the Mini-UART is used, ALT0 (0x4) points
to the PL011.
Based on that we select the UART driver to initialise.
This will allow console output in any case.
Change-Id: I620d3ce68de6c6576599f2a405636020e1fd1376
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
|