Commit Graph

5 Commits

Author SHA1 Message Date
Andre Przywara 5e6d821cb3 rpi: Allow using PL011 UART for RPi3/RPi4
The Broadcom 283x SoCs feature multiple UARTs: the mostly used
"Mini-UART", which is an 8250 compatible IP, and at least one PL011.
While the 8250 is usually used for serial console purposes, it suffers
from a design flaw, where its clock depends on the VPU clock, which can
change at runtime. This will reliably mess up the baud rate.
To avoid this problem, people might choose to use the PL011 UART for
the serial console, which is pin-mux'ed to the very same GPIO pins.
This can be done by adding "miniuart-bt" to the "dtoverlay=" line in
config.txt.

To prepare for this situation, use the newly gained freedom of sharing
one console_t pointer across different UART drivers, to introduce the
option of choosing the PL011 for the console.

This is for now hard-coded to choose the Mini-UART by default.
A follow-up patch will introduce automatic detection.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Change-Id: I8cf2522151e09ff4ff94a6d396aec6fc4b091a05
2020-03-17 13:44:49 +00:00
Andre Przywara 4f2b984852 rpi3: Move shared rpi3 files into common directory
To be able to share code more easily between the existing Raspberry Pi 3
and the upcoming Raspberry Pi 4 platform, move some code which is not
board specific into a "common" directory.

Change-Id: I9211ab2d754b040128fac13c2f0a30a5cc8c7f2c
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2019-09-13 16:54:21 +01:00
Andre Przywara 990ab78e78 rpi3: Move rng driver to drivers
To allow sharing the driver between the RPi3 and RPi4, move the random
number generator driver into the generic driver directory.

Change-Id: Iae94d7cb22c6bce3af9bff709d76d4caf87b14d1
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2019-09-13 16:54:21 +01:00
Andre Przywara c00311893d rpi3: Move VC mailbox driver into generic drivers directory
To allow sharing the driver between the RPi3 and RPi4, move the mailbox
driver into the generic driver directory.

Change-Id: I463e49acf82b02bf004f3d56482b7791f3020bc0
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2019-09-13 16:54:21 +01:00
Andre Przywara ab13addd84 rpi3: Add "rpi" platform directory
With the incoming support for the Raspberry Pi 4 boards, one directory
to serve both versions will not end up well.

Create an additional layer by inserting a "rpi" directory betweeen /plat
and rpi3, so that we can more easily share or separate files between the
two later.

Change-Id: I75adbb054fe7902f34db0fd5e579a55612dd8a5f
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2019-09-13 16:54:21 +01:00