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Message-ID: <795366b601b0b9bed2144ea94c08519dcf198beb.camel@redhat.com>
Subject: Re: [PATCH 1/3] resource: Add resource set range and size helpers
From: Philipp Stanner <pstanner@redhat.com>
To: Ilpo =?ISO-8859-1?Q?J=E4rvinen?= <ilpo.jarvinen@linux.intel.com>,  Bjorn
 Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org, Lorenzo Pieralisi
 <lpieralisi@kernel.org>,  Rob Herring <robh@kernel.org>, Krzysztof
 =?UTF-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,  linux-kernel@vger.kernel.org
Cc: Jonathan Hunter <jonathanh@nvidia.com>, 
	linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org, Robert
	Richter <rric@kernel.org>, Thierry Reding <thierry.reding@gmail.com>
Date: Wed, 12 Jun 2024 15:48:51 +0200
In-Reply-To: <20240612085629.5015-2-ilpo.jarvinen@linux.intel.com>
References: <20240612085629.5015-1-ilpo.jarvinen@linux.intel.com>
	 <20240612085629.5015-2-ilpo.jarvinen@linux.intel.com>
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On Wed, 2024-06-12 at 11:56 +0300, Ilpo J=C3=A4rvinen wrote:
> Setting the end address for a resource with a given size lacks a
> helper
> and is therefore open coded unlike the getter side which has a helper
> for resource size calculation.=C2=A0

"open coded"?=20

How about "coded manually unlike [...]"

> Also, almost all callsites that
> calculate end address for a resource also set the start address right

"an end address" or "the end address"?

> before it like this:
>=20
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0res->start =3D start_addr=
;
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0res->end =3D res->start +=
 size - 1;
>=20
> Thus, add resource_set_range(res, start_addr, size) that sets the
> start
> address and calculates the end address to simplify this often
> repeated
> fragment. In addition, introduce resource_set_size() for the cases
> where setting the start address of the resource is not necessary but
> note resource_set_range() is preferred.

"note"? I don't fully get that sentence.


Looks like a cool little improvement otherwise :)


P.

>=20
> Signed-off-by: Ilpo J=C3=A4rvinen <ilpo.jarvinen@linux.intel.com>
> ---
> =C2=A0include/linux/ioport.h | 32 ++++++++++++++++++++++++++++++++
> =C2=A01 file changed, 32 insertions(+)
>=20
> diff --git a/include/linux/ioport.h b/include/linux/ioport.h
> index db7fe25f3370..2a1d33ad151c 100644
> --- a/include/linux/ioport.h
> +++ b/include/linux/ioport.h
> @@ -216,6 +216,38 @@ struct resource *lookup_resource(struct resource
> *root, resource_size_t start);
> =C2=A0int adjust_resource(struct resource *res, resource_size_t start,
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 resource_size_t size);
> =C2=A0resource_size_t resource_alignment(struct resource *res);
> +
> +/**
> + * resource_set_size - Calculates resource end address from size and
> start address
> + * @res: The resource descriptor
> + * @size: The size of the resource
> + *
> + * Calculates the end address for @res based on @size.
> + *
> + * Note: The start address of @res must be set when calling this
> function.
> + * Use resource_set_range() if setting both the start address and
> @size.
> + */
> +static inline void resource_set_size(struct resource *res,
> resource_size_t size)
> +{
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0res->end =3D res->start + size=
 - 1;
> +}
> +
> +/**
> + * resource_set_range - Sets resource start and end addresses
> + * @res: The resource descriptor
> + * @start: The start address for the resource
> + * @size: The size of the resource
> + *
> + * Sets @res start address and calculates the end address based on
> @size.
> + */
> +static inline void resource_set_range(struct resource *res,
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 resou=
rce_size_t start,
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 resou=
rce_size_t size)
> +{
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0res->start =3D start;
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0resource_set_size(res, size);
> +}
> +
> =C2=A0static inline resource_size_t resource_size(const struct resource
> *res)
> =C2=A0{
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0return res->end - res->st=
art + 1;