[PATCH] bcm4908: initial work on the Broadcom BCM4908 target

[Rafał Miłecki]

On 08.01.2021 19:30, Adrian Schmutzler wrote:
>> -----Original Message-----
>> From: openwrt-devel [mailto:openwrt-devel-bounces at lists.openwrt.org]
>> On Behalf Of Rafal Milecki
>> Sent: Freitag, 8. Januar 2021 14:53
>> To: openwrt-devel at lists.openwrt.org
>> Cc: Rafał Miłecki <rafal at milecki.pl>
>> Subject: [PATCH] bcm4908: initial work on the Broadcom BCM4908 target
>>
>> From: Rafał Miłecki <rafal at milecki.pl>
>>
>> BCM4906, BCM4908 and BCM49408 are SoCs with 64 bit ARMv8 B53 CPUs.
>> Upstream Linux is slowly getting support for that SoCs family so it makes
>> sense to add target for it.
>>
>> It isn't usable yet (it only produces a bootable kernel) so "source-only"
>> is used.
>>
> 
> some nitpicks below, as usual.
> 
> [...]
> 
>> --- /dev/null
>> +++ b/target/linux/bcm4908/generic/target.mk
>> @@ -0,0 +1 @@
>> +BOARDNAME:=Generic
>> diff --git a/target/linux/bcm4908/image/Makefile
>> b/target/linux/bcm4908/image/Makefile
>> new file mode 100644
>> index 0000000000..672cdf40e6
>> --- /dev/null
>> +++ b/target/linux/bcm4908/image/Makefile
>> @@ -0,0 +1,39 @@
>> +# SPDX-License-Identifier: GPL-2.0-only
>> +
>> +include $(TOPDIR)/rules.mk
>> +include $(INCLUDE_DIR)/image.mk
>> +
>> +define Build/bcm4908lzma
>> +	$(STAGING_DIR_HOST)/bin/lzma e -lc1 -lp2 -pb2 -d22 $@ $@.new
>> +	mv $@.new $@
>> +endef
>> +
>> +define Device/Default
>> +  KERNEL := kernel-bin | bcm4908lzma
>> +  KERNEL_DEPENDS = $$(wildcard $(DTS_DIR)/$$(DEVICE_DTS).dts)
>> +  KERNEL_INITRAMFS_SUFFIX := .bin
>> +  KERNEL_INITRAMFS := kernel-bin | bcm4908lzma
>> +  FILESYSTEMS := squashfs
>> +  KERNEL_NAME := Image
>> +  IMAGE_NAME = $$(IMAGE_PREFIX)-$$(1).$$(2)
>> +  BLOCKSIZE := 128k
>> +  PAGESIZE := 2048
>> +endef
>> +
>> +define Device/asus-gt-ac5300
> 
> It would be nice if we could use the vendor_model scheme with underscore here, like for most of the other targets (i.e. asus_gt-ac5300 in this case).

Absolutely, thanks for pointing that out!


>> +  DEVICE_VENDOR := Asus
>> +  DEVICE_MODEL := GT-AC5300
>> +  DEVICE_DTS := broadcom/bcm4908/bcm4908-asus-gt-ac5300
> 
> This could be auto-assembled based on SOC variable and DEVICE_NAME/$1 eventually.

For now I'll just keep it in mind, I promise to get back to this when I
start working on generating images. That will require some device specific
files and identifying directories somehow.


>> +  IMAGES := bin
>> +endef
>> +TARGET_DEVICES += asus-gt-ac5300
>> +
> 
> [...]
> 
>> +--- /dev/null
>> ++++ b/arch/arm64/boot/dts/broadcom/bcm4908/bcm4908.dtsi
>> +@@ -0,0 +1,187 @@
>> ++// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
>> ++
>> ++#include <dt-bindings/interrupt-controller/irq.h>
>> ++#include <dt-bindings/interrupt-controller/arm-gic.h>
>> ++
>> ++/dts-v1/;
> 
> dts-v1 needs to be placed before any definitions to be valid. I assume the includes only contain macros (so don't count in that context), but one might still consider to move the dts-v1 in front of them, directly after the license. (Same argument applies indirectly to the includes in the DTS file above.

This is backport of upstream patch, so I can't just change it. I'll submit
upstream fix and then backport it.