On 26.03.2025 17:49, Oleksii Kurochko wrote:
> On 3/26/25 4:19 PM, Jan Beulich wrote:
>> On 25.03.2025 18:36, Oleksii Kurochko wrote:
>>> Introduce preinitialization stuff for the RISC-V Advanced Platform-Level
>>> Interrupt Controller (APLIC) in Xen:
>>> - Implementing the APLIC pre-initialization function (`aplic_preinit()`),
>>> ensuring that only one APLIC instance is supported in S mode.
>>> - Initialize APLIC's correspoinding DT node.
>>> - Declaring the DT device match table for APLIC.
>>> - Setting `aplic_info.hw_version` during its declaration.
>>> - Declaring an APLIC device.
>>>
>>> Since Microchip originally developed aplic.c [1], an internal discussion
>>> with them led to the decision to use the MIT license instead of the default
>>> GPL-2.0-only.
>>>
>>> [1]https://gitlab.com/xen-project/people/olkur/xen/-/commit/7cfb4bd4748ca268142497ac5c327d2766fb342d
>>>
>>> Signed-off-by: Romain Caritey<romain.cari...@microchip.com>
>>> Signed-off-by: Oleksii Kurochko<oleksii.kuroc...@gmail.com>
>> You recall that From: != 1st S-o-b is unusual, and wants some explanation.
>> IOW it's unclear who the original author of this patch is.
>
> I'm not 100% sure who should be the author. Such patch doesn't exist before
> but I took the changes
> based on the changes mentioned in commit message as [1].
>
> If you think that the author should be Romain, I am okay with that.
I can't sensibly form an opinion here. This needs settling between him and you.
>From your reply I'm not even convinced his S-o-b is legitimately there then.
You may want to use another, less standard tag in such a case (like the
Co-developed-by: that I've seen in use here and there) to still give credit to
him.
>>> --- /dev/null
>>> +++ b/xen/arch/riscv/aplic.c
>>> @@ -0,0 +1,49 @@
>>> +/* SPDX-License-Identifier: MIT */
>>> +
>>> +/*
>>> + * xen/arch/riscv/aplic.c
>>> + *
>>> + * RISC-V Advanced Platform-Level Interrupt Controller support
>>> + *
>>> + * Copyright (c) 2023-2024 Microchip.
>>> + * Copyright (c) 2024-2025 Vates
>>> + */
>>> +
>>> +#include <xen/errno.h>
>>> +#include <xen/init.h>
>>> +#include <xen/types.h>
>>> +
>>> +#include <asm/device.h>
>>> +#include <asm/intc.h>
>>> +
>>> +static struct intc_info aplic_info = {
>>> + .hw_version = INTC_APLIC
>>> +};
>> Is this going to be written to (much) post-init? IOW - __read_mostly or
>> even __ro_after_init?
>
> I think that __read_mostly would be better because intc_info structure in the
> future
> will contain member "void *private". And in `private` it can be a data which
> can
> be changed.
You mean the pointer can change? Or merely what it points to, i.e. ...
> For example, `private` can contain an aplic_priv structure:
> struct aplic_priv {
> /* number of irqs */
> uint32_t nr_irqs;
>
> /* base physical address and size */
> paddr_t paddr_start;
> paddr_t paddr_end;
> uint64_t size;
>
> /* registers */
> struct aplic_regs *regs;
>
> /* imsic configuration */
> const struct imsic_config *imsic_cfg;
> };
>
> and regs from aplic_priv structure can be changed in runtime.
... the contents of such a struct? In this latter case the struct instance
here can still be __ro_after_init as long as the pointer is set from an
__init function.
Jan
