r354875 pushed VCBUS <-> ARMC translations to runtime determination, but
incorrectly mapped addresses for the BCM2836 -- SOC_BCM2835 and SOC_BCM2836
are actually mutually exclusive, so the BCM2836 config (GENERIC) would have
taken the latter path in the header and used 0x3f000000 as peripheral start.
Easily fixed -- split out the BCM2836 into its own memmap config and use
that instead if SOC_BCM2836 is included. With this, we get back to userland
again.
Reported by: Marek Zarychta <zarychtam@plan-b.pwste.edu.pl>
It's unclear how this didn't get caught in my last iteration, but the fix is
easy- the interface is still compatible, it was just gratuituously renamed
to match my arbitrary definition of consistency... VCBUS, the BCM2835 name,
represents an address on the VideoCore CPU Bus.
In a similar fashion, while it is a physical address, the ARMC portion
represents that these are addresses as seen by the ARM CPU.
To make things even more fun, the BCM2711 peripheral documentation describes
not virtual address space vs. physical address space, but instead the 32-bit
address map vs. the address map in "Low Peripheral" mode. The latter of
these is what the *ARMC* macros translate to/from.
We could maintain the static conversions for the !AArch64 Raspberry Pis, but
I'm not sure it's worth it -- we'll traverse the platform list exactly once
(of which there are only two for armv7), then every conversion there-after
traverses the memory map listing of which there are at-most two entries for
these boards: sdram and peripheral space.
Detecting this at runtime is necessary for the AArch64 SOC, though, because
of the distinct IO windows being otherwise not discernible just from support
compiled into the kernel. We currently select the correct window based on
/compatible in the FDT.
We also use a similar mechanism to describe the DMA restrictions- the RPi 4
can have up to 4GB of RAM while the DMA controller and mailbox mechanism can
technically, kind of, only access the lowest 1GB. See the comment in
bcm2835_vcbus.h for a fun description/clarification of this.
Differential Revision: https://reviews.freebsd.org/D22301
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
- Rename SOC_BCM2837 to SOC_BRCM_BCM2837, put it to opt_soc.h
- do not use files.XXX files, just move required sources to
conf/files.arm64 and make them depend on soc_brcm_bcm2837
Suggested by: andrew
RPI3 kernel config builds kernel compatible with latest upstream device
tree and firmware: https://github.com/raspberrypi/firmware/tree/master/boot
As of today it's 597c662a613df1144a6bc43e5f4505d83bd748ca
Default console is PL01x, so pi3-disable-bt dt overlay should be configured
in config.txt and stock U-Boot should be patched to use proper serial port.
Yet unsupported: SMP, VCHIQ, RNG driver. RNG requires some work due to
upstream device tree incompatibility.
Multiple people contributed to this work over time: db@, loos@, manu@
receives video memory address from VideoCore through property mailbox
channel. Older versions of firmware (and the one that is currently part
of sysutils/u-boot-rpi and sysutils/u-boot-rpi2) returned real physical
address, newer one returns VideoCore bus address, so we need to convert
it to actual physical address. this version works with both older and
newer interface.
