Re: [PATCH v2 2/3] MIPS: cm/cpc: export some missing symbols to be able to use them from driver code

From: Sergio Paracuellos <sergio.paracuellos@gmail.com>
To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Yanteng Si <siyanteng01@gmail.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	bcm-kernel-feedback-list@broadcom.com,
	Yanteng Si <siyanteng@loongson.cn>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Rob Herring <robh@kernel.org>,
	kw@linux.com, Bjorn Helgaas <bhelgaas@google.com>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	linux-pci <linux-pci@vger.kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	"moderated list:ARM/Mediatek SoC support" 
	<linux-mediatek@lists.infradead.org>,
	"open list:MIPS" <linux-mips@vger.kernel.org>,
	chenhuacai@kernel.org, sterlingteng@gmail.com,
	Linux Next Mailing List <linux-next@vger.kernel.org>
Subject: Re: [PATCH v2 2/3] MIPS: cm/cpc: export some missing symbols to be able to use them from driver code
Date: Thu, 28 Oct 2021 11:34:47 +0200	[thread overview]
Message-ID: <CAMhs-H_m=pz4jU_cY-A6PRjR3OYy2zKH0=HN=vFDF2XOk60xBg@mail.gmail.com> (raw)
In-Reply-To: <20211028092318.GA6574@alpha.franken.de>

Hi Thomas,

On Thu, Oct 28, 2021 at 11:24 AM Thomas Bogendoerfer
<tsbogend@alpha.franken.de> wrote:
>
> On Thu, Oct 28, 2021 at 06:11:18AM +0200, Sergio Paracuellos wrote:
> > On Thu, Oct 28, 2021 at 6:05 AM Yanteng Si <siyanteng01@gmail.com> wrote:
> > >
> > > Since commit 2bdd5238e756 ("PCI: mt7621: Add MediaTek MT7621 PCIe host controller driver")
> > > the MT7621 PCIe host controller driver is built as a module but modpost complains once these
> > > drivers become modules.
> > >
> > > ERROR: modpost: "mips_cm_unlock_other" [drivers/pci/controller/pcie-mt7621.ko] undefined!
> > > ERROR: modpost: "mips_cpc_base" [drivers/pci/controller/pcie-mt7621.ko] undefined!
> > > ERROR: modpost: "mips_cm_lock_other" [drivers/pci/controller/pcie-mt7621.ko] undefined!
> > > ERROR: modpost: "mips_cm_is64" [drivers/pci/controller/pcie-mt7621.ko] undefined!
> > > ERROR: modpost: "mips_gcr_base" [drivers/pci/controller/pcie-mt7621.ko] undefined!
> > >
> > > Let's just export them.
> > >
> > > Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
> > > ---
> > >  arch/mips/kernel/mips-cm.c  | 5 +++++
> > >  arch/mips/kernel/mips-cpc.c | 1 +
> > >  2 files changed, 6 insertions(+)
> > >
> >
> > Reviewed-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
>
> could we instead make the pcie-mt761 driver non modular ? Exporting
> all MIPS specific stuff for just making an essential driver modular
> doesn't IMHO make much sense.

The driver is modular because I have been advised other times that new
drivers should be able to be compiled as modules and we should avoid
using 'bool' in Kconfig for new drivers. That's the only reason. I am
also always including as 'y' the driver since for me not having pci in
my boards has no sense... I am ok in changing Kconfig to be 'bool'
instead of 'tristate', but I don't know what should be the correct
thing to do in this case. Thoughts?

Best regards,
    Sergio Paracuellos

>
> Thomas.
>
> --
> Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
> good idea.                                                [ RFC1925, 2.3 ]