From: Stephen Warren <swarren@wwwdotorg.org>
To: Hiroshi Doyu <hdoyu@nvidia.com>,
swarren@nvidia.com, will.deacon@arm.com, grant.likely@linaro.org,
thierry.reding@gmail.com, robherring2@gmail.com, joro@8bytes.org
Cc: mark.rutland@arm.com, devicetree@vger.kernel.org,
lorenzo.pieralisi@arm.com, linux-kernel@vger.kernel.org,
iommu@lists.linux-foundation.org, galak@codeaurora.org,
linux-tegra@vger.kernel.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCHv7 02/12] iommu/of: introduce a global iommu device list
Date: Mon, 16 Dec 2013 11:32:47 -0700 [thread overview]
Message-ID: <52AF474F.7080701@wwwdotorg.org> (raw)
In-Reply-To: <1386835033-4701-3-git-send-email-hdoyu@nvidia.com>
On 12/12/2013 12:57 AM, Hiroshi Doyu wrote:
> This enables to find an populated IOMMU device via a device node. This
> can be used to see if an dependee IOMMU is populated or not to keep
> correct device population order. Client devices need to wait an IOMMU
> to be populated.
>
> Suggested by Thierry Reding and copied his example code.
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> +static struct iommu *of_find_iommu_by_node(struct device_node *np)
> +{
> + struct iommu *iommu;
> +
> + mutex_lock(&iommus_lock);
> + list_for_each_entry(iommu, &iommus_list, list) {
> + if (iommu->dev->of_node == np) {
> + mutex_unlock(&iommus_lock);
Now that the list is unlocked, the IOMMU could be removed from the list,
and the driver unregistered. Should you do something like
iommu_get(iommu); before the mutex_unlock() call, and call iommu_put()
somewhere (i.e. in the next patch ...)?
next prev parent reply other threads:[~2013-12-16 18:32 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-12 7:57 [PATCHv7 00/12] Unifying SMMU driver among Tegra SoCs Hiroshi Doyu
2013-12-12 7:57 ` [PATCHv7 01/12] of: introduce of_property_for_each_phandle_with_args() Hiroshi Doyu
2013-12-16 18:29 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 02/12] iommu/of: introduce a global iommu device list Hiroshi Doyu
2013-12-16 18:32 ` Stephen Warren [this message]
2013-12-12 7:57 ` [PATCHv7 03/12] iommu/of: check if dependee iommu is ready or not Hiroshi Doyu
2013-12-16 18:34 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 04/12] driver/core: populate devices in order for IOMMUs Hiroshi Doyu
2013-12-12 11:39 ` Grant Likely
2013-12-13 2:14 ` Greg KH
2013-12-14 12:24 ` Thierry Reding
2013-12-14 14:28 ` Hiroshi Doyu
2013-12-16 18:26 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 05/12] iommu/core: add ops->{bound,unbind}_driver() Hiroshi Doyu
2013-12-16 18:42 ` Stephen Warren
2013-12-30 13:45 ` Joerg Roedel
2013-12-12 7:57 ` [PATCHv7 06/12] ARM: tegra: create a DT header defining SWGROUP ID Hiroshi Doyu
2013-12-18 8:02 ` Mark Zhang
2013-12-18 16:27 ` Stephen Warren
2013-12-20 12:35 ` Thierry Reding
2013-12-20 17:36 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 07/12] iommu/tegra: smmu: register device to iommu dynamically Hiroshi Doyu
2013-12-16 18:46 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 08/12] iommu/tegra: smmu: calculate ASID register offset by ID Hiroshi Doyu
2013-12-16 19:02 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 09/12] iommu/tegra: smmu: get swgroups from DT "iommus=" Hiroshi Doyu
2013-12-16 19:09 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 10/12] iommu/tegra: smmu: allow duplicate ASID wirte Hiroshi Doyu
2013-12-16 19:19 ` Stephen Warren
2013-12-12 7:57 ` [PATCHv7 11/12] iommu/tegra: smmu: Rename hwgrp -> swgroups Hiroshi Doyu
2013-12-12 7:57 ` [PATCHv7 12/12] iommu/tegra: smmu: add SMMU to an global iommu list Hiroshi Doyu
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=52AF474F.7080701@wwwdotorg.org \
--to=swarren@wwwdotorg.org \
--cc=devicetree@vger.kernel.org \
--cc=galak@codeaurora.org \
--cc=grant.likely@linaro.org \
--cc=hdoyu@nvidia.com \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=lorenzo.pieralisi@arm.com \
--cc=mark.rutland@arm.com \
--cc=robherring2@gmail.com \
--cc=swarren@nvidia.com \
--cc=thierry.reding@gmail.com \
--cc=will.deacon@arm.com \
/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).