Message-ID: <4f98164406cfd6da084f9ef617a6668dc4e8d44b.camel@linux.ibm.com>
Subject: Re: [PATCH 1/2] pcmcia : make PCMCIA depend on HAS_IOMEM
From:   Niklas Schnelle <schnelle@linux.ibm.com>
To:     Baoquan He <bhe@redhat.com>, linux-kernel@vger.kernel.org
Cc:     linux-mm@kvack.org, linux-s390@vger.kernel.org,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        Arnd Bergmann <arnd@arndb.de>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Date:   Thu, 16 Feb 2023 10:05:15 +0100
In-Reply-To: <20230216073403.451455-1-bhe@redhat.com>
References: <20230216073403.451455-1-bhe@redhat.com>
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On Thu, 2023-02-16 at 15:34 +0800, Baoquan He wrote:
> On s390 systems (aka mainframes), it has classic channel devices for
> networking and permanent storage that are currently even more common
> than PCI devices. Hence it could have a fully functional s390 kernel
> with CONFIG_PCI=3Dn, then the relevant iomem mapping functions
> [including ioremap(), devm_ioremap(), etc.] are not available.
>=20
> Here let depend PCMCIA on HAS_IOMEM so that it won't be built to
> cause below compiling error if PCI is unset.
>=20
> -------------------------------------------------------
> ld: drivers/pcmcia/cistpl.o: in function `set_cis_map':
> cistpl.c:(.text+0x1202): undefined reference to `ioremap'
> ld: cistpl.c:(.text+0x13b0): undefined reference to `iounmap'
> ld: cistpl.c:(.text+0x14a6): undefined reference to `iounmap'
> ld: cistpl.c:(.text+0x1544): undefined reference to `ioremap'
> ld: drivers/pcmcia/cistpl.o: in function `release_cis_mem':
> cistpl.c:(.text+0x3f14): undefined reference to `iounmap'
>=20
> Link: https://lore.kernel.org/all/Y0TcaZD4nB1w+mAQ@MiWiFi-R3L-srv/T/#u
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Dominik Brodowski <linux@dominikbrodowski.net>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> ---
>  drivers/pcmcia/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
>=20
> diff --git a/drivers/pcmcia/Kconfig b/drivers/pcmcia/Kconfig
> index 1525023e49b6..7c412bbe8bbe 100644
> --- a/drivers/pcmcia/Kconfig
> +++ b/drivers/pcmcia/Kconfig
> @@ -20,6 +20,7 @@ if PCCARD
>=20=20
>  config PCMCIA
>  	tristate "16-bit PCMCIA support"
> +	depends on HAS_IOMEM
>  	select CRC32
>  	default y
>  	help

Not sure how many PCMCIA drivers only use I/O memory but not I/O ports
the latter of which are badly stubbed out on s390, though at leat they
compile. I have a series on that part that I intend to send a new
version for soon=E2=84=A2. That said yes this does solve the compilation is=
sue
and there could be drivers which rely only on I/O memory and are not
broken in principle.

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>