From: Tomasz Nowicki <tomasz.nowicki@linaro.org>
To: Arnd Bergmann <arnd@arndb.de>, linux-arm-kernel@lists.infradead.org
Cc: Liviu Dudau <liviu@dudau.co.uk>, Tony Luck <tony.luck@intel.com>,
Russell King <linux@arm.linux.org.uk>,
linux-pci@vger.kernel.org, x86@kernel.org,
linux-kernel@vger.kernel.org, Xinwei Hu <huxinwei@huawei.com>,
Bjorn Helgaas <bhelgaas@google.com>,
Thierry Reding <thierry.reding@gmail.com>,
Suravee.Suthikulpanit@amd.com,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Yijing Wang <wangyijing@huawei.com>,
linux-ia64@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
Wuyun <wuyun.wu@huawei.com>,
linuxppc-dev@lists.ozlabs.org
Subject: Re: [RFC PATCH 00/16] Refine PCI host bridge scan interfaces
Date: Thu, 20 Nov 2014 12:54:48 +0100 [thread overview]
Message-ID: <546DD688.60705@linaro.org> (raw)
In-Reply-To: <1463511.o4kE8TX3Bd@wuerfel>
On 17.11.2014 15:13, Arnd Bergmann wrote:
> On Monday 17 November 2014 18:21:34 Yijing Wang wrote:
>> This series is based Linux 3.18-rc1 and Lorenzo Pieralisi's
>> arm PCI domain cleanup patches, link:
>> https://patchwork.ozlabs.org/patch/407585/
>>
>> Current pci scan interfaces like pci_scan_root_bus() and directly
>> call pci_create_root_bus()/pci_scan_child_bus() lack flexiblity.
>> Some platform infos like PCI domain and msi_chip have to be
>> associated to PCI bus by some arch specific function.
>> We want to make a generic pci_host_bridge, and make it hold
>> the platform infos or hook. Then we could eliminate the lots
>> of arch pci_domain_nr, also we could associate some platform
>> ops something like pci_get_msi_chip(struct pci_dev *dev)
>> with pci_host_bridge to avoid introduce arch weak functions.
>>
>> This RFC version not for all platforms, just applied the new
>> scan interface in x86/arm/powerpc/ia64, I will refresh other
>> platforms after the core pci scan interfaces are ok.
>
> I think overall this is a good direction to take, in particular
> moving more things into struct pci_host_bridge so we can
> slim down the architecture specific code.
>
> I don't particularly like the way you use the 'pci_host_info'
> to pass callback pointers and some of the generic information.
> This duplicates some of the issues we are currently trying
> to untangle in the arm32 code to make drivers easier to share
> between architectures.
>
> As a general approach, I'd rather see generic helper functions
> being exported by the PCI core that a driver may or may not
> call.
> The way you split the interface between things that happen
> before scanning the buses (pci_create_host_bridge) and
> the actual scanning (__pci_create_root_bus, pci_scan_child_bus)
> seems very helpful and I think we can expand that concept further:
>
> - The normal pci_create_host_bridge() function can contain
> all of the DT scanning functions (finding bus/mem/io resources,
> finding the msi-parent), while drivers that don't depend on DT
> for this information can call the same function and fill the
> same things after they have the pci_host_bridge pointer.
How about finding PCI domain number (in the DT way) within
pci_create_host_bridge() too ?
Tomasz
next prev parent reply other threads:[~2014-11-20 11:54 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-17 10:21 [RFC PATCH 00/16] Refine PCI host bridge scan interfaces Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 01/16] PCI: Enhance pci_scan_root_bus() to support default IO/MEM resources Yijing Wang
2014-11-17 10:08 ` Arnd Bergmann
2014-11-18 7:44 ` Yijing Wang
2014-11-18 9:36 ` Arnd Bergmann
2014-11-18 11:46 ` Yijing Wang
2014-11-18 14:23 ` Liviu Dudau
2014-11-19 1:15 ` Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 02/16] PCI: Use pci_scan_root_bus() instead of pci_scan_bus() Yijing Wang
2014-11-18 14:28 ` Liviu Dudau
2014-11-19 1:19 ` Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 03/16] PCI: Clean up pci_scan_bus() Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 04/16] PCI: Rip out pci_bus_add_devices() from pci_scan_root_bus() Yijing Wang
2014-11-18 14:34 ` Liviu Dudau
2014-11-19 1:21 ` Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 05/16] PCI: Use pci_scan_root_bus() instead of pci_scan_bus_parented() Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 06/16] PCI: Use u32 type to combine PCI domain and bus number Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 07/16] PCI: Separate pci_host_bridge creation out of pci_create_root_bus() Yijing Wang
2014-11-17 10:56 ` Arnd Bergmann
2014-11-18 8:32 ` Yijing Wang
2014-11-18 9:30 ` Arnd Bergmann
2014-11-18 11:44 ` Yijing Wang
2014-11-18 12:25 ` Arnd Bergmann
2014-11-18 12:41 ` Yijing Wang
2014-11-18 14:48 ` Liviu Dudau
2014-11-19 2:24 ` Yijing Wang
2014-11-19 16:29 ` Liviu Dudau
2014-11-20 2:00 ` Yijing Wang
2014-11-18 15:30 ` Liviu Dudau
2014-11-19 1:42 ` Yijing Wang
2014-11-19 16:37 ` Liviu Dudau
2014-11-20 2:47 ` Yijing Wang
2014-11-20 9:47 ` Liviu Dudau
2014-11-21 2:53 ` Yijing Wang
2014-11-21 9:53 ` Liviu Dudau
2014-11-17 10:21 ` [RFC PATCH 08/16] PCI: Introduce pci_scan_host_bridge() and pci_host_info Yijing Wang
2014-11-18 15:42 ` Liviu Dudau
2014-11-19 2:09 ` Yijing Wang
2014-11-19 16:41 ` Liviu Dudau
2014-11-20 2:54 ` Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 09/16] PCI: Associate .get_msi_ctrl() with pci_host_bridge Yijing Wang
2014-11-17 15:03 ` Lorenzo Pieralisi
2014-11-17 10:21 ` [RFC PATCH 10/16] PCI: Add of_scan_bus() to pci_host_info Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 11/16] x86/PCI: Use pci_scan_host_bridge() instead of pci_create_root_bus() Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 12/16] ia64/PCI: Remove the redundant bus variable Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 13/16] ia64/PCI: Use pci_scan_host_bridge() to refactor pci_acpi_scan_root() Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 14/16] arm/PCI: Introduce pci_get_domain_nr() Yijing Wang
2014-11-17 12:08 ` Lorenzo Pieralisi
2014-11-18 0:55 ` Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 15/16] arm/PCI: Use pci_scan_host_bridge() instead of pci_scan_root_bus() Yijing Wang
2014-11-17 10:21 ` [RFC PATCH 16/16] powerpc/PCI: Use pci_scan_host_bridge() to scan PCI bus Yijing Wang
2014-11-17 14:13 ` [RFC PATCH 00/16] Refine PCI host bridge scan interfaces Arnd Bergmann
2014-11-18 11:17 ` Yijing Wang
2014-11-18 11:30 ` Arnd Bergmann
2014-11-18 11:45 ` Lorenzo Pieralisi
2014-11-18 12:14 ` Yijing Wang
2014-11-18 12:17 ` Yijing Wang
2014-11-18 12:27 ` Arnd Bergmann
2014-11-20 12:01 ` Tomasz Nowicki
2014-11-20 13:15 ` Arnd Bergmann
2014-11-20 11:54 ` Tomasz Nowicki [this message]
2014-11-20 12:08 ` Liviu Dudau
2014-11-20 12:53 ` Tomasz Nowicki
2014-11-20 16:39 ` Liviu Dudau
2014-11-21 2:58 ` Yijing Wang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=546DD688.60705@linaro.org \
--to=tomasz.nowicki@linaro.org \
--cc=Suravee.Suthikulpanit@amd.com \
--cc=arnd@arndb.de \
--cc=benh@kernel.crashing.org \
--cc=bhelgaas@google.com \
--cc=huxinwei@huawei.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=liviu@dudau.co.uk \
--cc=tglx@linutronix.de \
--cc=thierry.reding@gmail.com \
--cc=tony.luck@intel.com \
--cc=wangyijing@huawei.com \
--cc=wuyun.wu@huawei.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).