[PATCH v3 2/5] powerpc: apm82181: create shared dtsi for APM bluestone

[Christian Lamparter]

On 2020-09-15 03:05, Rob Herring wrote:
> On Sun, Sep 06, 2020 at 12:06:12AM +0200, Christian Lamparter wrote:
>> This patch adds an DTSI-File that can be used by various device-tree
>> files for APM82181-based devices.
>>
>> Some of the nodes (like UART, PCIE, SATA) are used by the uboot and
>> need to stick with the naming-conventions of the old times'.
>> I've added comments whenever this was the case.
>>
>> Signed-off-by: Chris Blake <chrisrblake93 at gmail.com>
>> Signed-off-by: Christian Lamparter <chunkeey at gmail.com>
>> ---
>> rfc v1 -> v2:
>> 	- removed PKA (this CryptoPU will need driver)
>> 	- stick with compatibles, nodes, ... from either
>> 	  Bluestone (APM82181) or Canyonlands (PPC460EX).
>> 	- add labels for NAND and NOR to help with access.
>> v2 -> v3:
>> 	- nodename of pciex at d.... was changed to pcie at d..
>> 	  due to upstream patch.
>> 	- use simple-bus on the ebc, opb and plb nodes
>> ---
>>   arch/powerpc/boot/dts/apm82181.dtsi | 466 ++++++++++++++++++++++++++++
>>   1 file changed, 466 insertions(+)
>>   create mode 100644 arch/powerpc/boot/dts/apm82181.dtsi
>>
>> diff --git a/arch/powerpc/boot/dts/apm82181.dtsi b/arch/powerpc/boot/dts/apm82181.dtsi
>> new file mode 100644
>> index 000000000000..60283430978d
>> --- /dev/null
>> +++ b/arch/powerpc/boot/dts/apm82181.dtsi
>> @@ -0,0 +1,466 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * Device Tree template include for various APM82181 boards.
>> + *
>> + * The SoC is an evolution of the PPC460EX predecessor.
>> + * This is why dt-nodes from the canyonlands EBC, OPB, USB,
>> + * DMA, SATA, EMAC, ... ended up in here.
>> + *
>> + * Copyright (c) 2010, Applied Micro Circuits Corporation
>> + * Author: Tirumala R Marri <tmarri at apm.com>,
>> + *	   Christian Lamparter <chunkeey at gmail.com>,
>> + *	   Chris Blake <chrisrblake93 at gmail.com>
>> + */
>> +
>> +#include <dt-bindings/dma/dw-dmac.h>
>> +#include <dt-bindings/input/input.h>
>> +#include <dt-bindings/interrupt-controller/irq.h>
>> +#include <dt-bindings/gpio/gpio.h>
>> +
>> +/ {
>> +	#address-cells = <2>;
>> +	#size-cells = <1>;
>> +	dcr-parent = <&{/cpus/cpu at 0}>;
>> +
>> +	aliases {
>> +		ethernet0 = &EMAC0; /* needed for BSP u-boot */
>> +	};
>> +
>> +	cpus {
>> +		#address-cells = <1>;
>> +		#size-cells = <0>;
>> +
>> +		CPU0: cpu at 0 {
>> +			device_type = "cpu";
>> +			model = "PowerPC,apm82181";
> 
> This doesn't match the existing bluestone dts file.
> 
> Please separate any restructuring from changes.


"I see" (I'm including your comment of the dt-binding as well).

I'm getting the vibe that I better should not touch that bluestone.dts.
An honestly, looking at the series and patches that the APM-engineers
posted back in the day, I can see why this well is so poisoned... and
stuff like SATA/AHBDMA/USB/GPIO/CPM/... was missing.

As for the devices. In the spirit of Arnd Bergmann's post of
<https://lkml.org/lkml/2020/3/30/195>

|It would be nice to move over the the bluestone .dts to the apm82181.dtsi file
|when that gets added, if only to ensure they use the same description for each
|node, but that shouldn't stop the addition of the new file if that is needed for
|distros to make use of a popular device.
|I see a couple of additional files in openwrt.

I mean I don't have the bluestone dev board, just the consumer devices.
Would it be possible to support those? I can start from a "skeleton" apm82181.dtsi
This would just include CPU, Memory (SD-RAM+L2C+OCM), UIC (Interrupt-Controller),
the PLB+OBP+EBC Busses and UART. Just enough to make a board "boot from ram".

And then add nodes for PCIE+MSI, AHBDMA+SATA, I2C, Ethernet, NAND+NOR and finally
the Crypto each in separate patches.