Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH 19/28] nios2: Device tree support | Date | Tue, 22 Apr 2014 15:42:16 +0200 |
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On Friday 18 April 2014, Ley Foon Tan wrote: > diff --git a/arch/nios2/boot/dts/3c120_devboard.dts b/arch/nios2/boot/dts/3c120_devboard.dts > new file mode 100644 > index 0000000..cad29a9 > --- /dev/null > +++ b/arch/nios2/boot/dts/3c120_devboard.dts > @@ -0,0 +1,205 @@ > +/* > + * Copyright (C) 2013 Altera Corporation > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see <http://www.gnu.org/licenses/>. > + * > + * This file is generated by sopc2dts. > + */ > + > +/dts-v1/; > + > +/ { > + model = "ALTR,qsys_ghrd_3c120"; > + compatible = "ALTR,qsys_ghrd_3c120";
You have a mix of "ALTR" and "altr" prefixes. The general recommendation is to use lower-case letters, which is also what is used on ARM socfpga, and what is documented in Documentation/devicetree/bindings/vendor-prefixes.txt for Altera.
> + sopc@0 { > + device_type = "soc"; > + ranges; > + #address-cells = < 1 >; > + #size-cells = < 1 >; > + compatible = "ALTR,avalon", "simple-bus"; > + bus-frequency = < 125000000 >; > + > + pb_cpu_to_io: bridge@0x8000000 { > + compatible = "simple-bus"; > + reg = < 0x08000000 0x00800000 >;
Are these all synthesized devices, or is there also some hardwired logic? It often makes sense to split out the reusable parts into a separate .dtsi file that gets included by every implementation.
> + #address-cells = < 1 >; > + #size-cells = < 1 >; > + ranges = < 0x00400000 0x08400000 0x00000020 > + 0x00004D40 0x08004D40 0x00000008 > + 0x00004D50 0x08004D50 0x00000008 > + 0x00004000 0x08004000 0x00000400 > + 0x00004400 0x08004400 0x00000040 > + 0x00004800 0x08004800 0x00000040 > + 0x00002000 0x08002000 0x00002000 > + 0x00004C80 0x08004C80 0x00000020 > + 0x00004CC0 0x08004CC0 0x00000010 > + 0x00004CE0 0x08004CE0 0x00000010 > + 0x00004D00 0x08004D00 0x00000010 >;
A few style comments:
- no whitespace in the after '<' or before '> - put each entry into its own '<...>' group. - lower-case characters for hex digits - The ranges should reflect what the bus actually translates, which is typically not individual bytes but rather whole address ranges. - sort numerically.
The above could look like
ranges = <0x00000000 0x08000000 0x00010000>, <0x00400000 0x08400000 0x00001000>;
> + timer_1ms: timer@0x400000 { > + compatible = "ALTR,timer-1.0"; > + > + sysid: sysid@0x4d40 { > + compatible = "ALTR,sysid-1.0"; > + reg = < 0x00004D40 0x00000008 >;
> + jtag_uart: serial@0x4d50 { > + compatible = "ALTR,juart-1.0"; > + reg = < 0x00004D50 0x00000008 >; > + > + tse_mac: ethernet@0x4000 { > + compatible = "ALTR,tse-1.0";
Does each one of these have a binding document in Documentation/devicetree/bindings?
I've looked only at the tse binding, which you seem to be violating in a few places:
- compatible string is "ALTR,tse-1.0", not "altr,tse-1.0"
> + reg = < 0x00004000 0x00000400 > + 0x00004400 0x00000040 > + 0x00004800 0x00000040 > + 0x00002000 0x00002000 >; > + reg-names = "control_port", "rx_csr", "tx_csr", "s1";
- wrong order, missing "tx_desc" and "rx_desc" entries
> + rx-fifo-depth = < 8192 >; > + tx-fifo-depth = < 8192 >; > + address-bits = < 48 >;
address-bits is not documented
> + max-frame-size = < 1518 >; > + local-mac-address = [ 02 00 00 00 00 00 ]; > + phy-mode = "rgmii-id"; > + ALTR,mii-id = < 0 >;
ALTR,mii-id is not documented, and required "phy-addr" is missing.
> diff --git a/arch/nios2/boot/linked_dtb.S b/arch/nios2/boot/linked_dtb.S > new file mode 100644 > index 0000000..071f922db338e2cb4064bc77bf346f50e584d04f > --- /dev/null > +++ b/arch/nios2/boot/linked_dtb.S > + */ > +.section .dtb.init.rodata,"a" > +.incbin "arch/nios2/boot/system.dtb"
Linking in the dtb file is really against the point of device trees. You should require boot loaders to pass the dtb seperately.
> + soc_dev_attr->soc_id = kasprintf(GFP_KERNEL, "%u", NIOS2_ID_DEFAULT); > + soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%d", > + NIOS2_REVISION_DEFAULT);
These are hardcoded constants. If there is no way to identify the hardware from looking at the registers, better don't fill these at all.
> + soc_dev = soc_device_register(soc_dev_attr); > + if (IS_ERR_OR_NULL(soc_dev)) {
Never use IS_ERR_OR_NULL().
If an interface can return an error code, you should rely on never seeing NULL, or treating it as a valid pointer.
> +static int __init nios2_device_probe(void) > +{ > + nios2_soc_device_init(); > + > + of_platform_bus_probe(NULL, altera_of_bus_ids, NULL); > + return 0; > +}
This function can get merged into nios2_soc_device_init.
Arnd
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