From: Arnd Bergmann <arnd@arndb.de>
To: Sven Peter <sven@svenpeter.dev>
Cc: Hector Martin <marcan@marcan.st>,
Alyssa Rosenzweig <alyssa@rosenzweig.io>,
Rob Herring <robh+dt@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@fb.com>,
Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
Marc Zyngier <maz@kernel.org>, DTML <devicetree@vger.kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-nvme@lists.infradead.org
Subject: Re: [PATCH 4/9] soc: apple: Add SART driver
Date: Mon, 21 Mar 2022 18:07:39 +0100 [thread overview]
Message-ID: <CAK8P3a19F8K0MvZV_R6HrmmR+WBsDge+u6U3iEVEjZ74i6+nEg@mail.gmail.com> (raw)
In-Reply-To: <20220321165049.35985-5-sven@svenpeter.dev>
On Mon, Mar 21, 2022 at 5:50 PM Sven Peter <sven@svenpeter.dev> wrote:
>
> The NVMe co-processor on the Apple M1 uses a DMA address filter called
> SART for some DMA transactions. This adds a simple driver used to
> configure the memory regions from which DMA transactions are allowed.
>
> Co-developed-by: Hector Martin <marcan@marcan.st>
> Signed-off-by: Hector Martin <marcan@marcan.st>
> Signed-off-by: Sven Peter <sven@svenpeter.dev>
Can you add some explanation about why this uses a custom interface
instead of hooking into the dma_map_ops?
> +static void sart2_get_entry(struct apple_sart *sart, int index, u8 *flags,
> + phys_addr_t *paddr, size_t *size)
> +{
> + u32 cfg = readl_relaxed(sart->regs + APPLE_SART2_CONFIG(index));
> + u32 paddr_ = readl_relaxed(sart->regs + APPLE_SART2_PADDR(index));
Why do you use the _relaxed() accessors here and elsewhere in the driver?
> +struct apple_sart *apple_sart_get(struct device *dev)
> +{
> + struct device_node *sart_node;
> + struct platform_device *sart_pdev;
> + struct apple_sart *sart;
> +
> + sart_node = of_parse_phandle(dev->of_node, "apple,sart", 0);
> + if (!sart_node)
> + return ERR_PTR(ENODEV);
The error pointers need to take negative values, like 'ERR_PTR(-ENODEV)',
here and everywhere else in the driver.
Arnd
next prev parent reply other threads:[~2022-03-21 17:08 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-21 16:50 [PATCH 0/9] Apple M1 (Pro/Max) NVMe driver Sven Peter
2022-03-21 16:50 ` [PATCH 1/9] dt-bindings: soc: apple: Add Apple SART Sven Peter
2022-03-31 21:23 ` Rob Herring
2022-04-02 12:58 ` Sven Peter
2022-03-21 16:50 ` [PATCH 2/9] dt-bindings: soc: apple: Add ANS NVMe Sven Peter
2022-03-23 11:14 ` Krzysztof Kozlowski
2022-04-02 13:05 ` Sven Peter
2022-04-02 16:06 ` Krzysztof Kozlowski
2022-03-21 16:50 ` [PATCH 3/9] soc: apple: Always include Makefile Sven Peter
2022-03-21 16:50 ` [PATCH 4/9] soc: apple: Add SART driver Sven Peter
2022-03-21 17:07 ` Arnd Bergmann [this message]
2022-04-02 12:38 ` Sven Peter
2022-04-02 19:07 ` Arnd Bergmann
2022-04-04 14:58 ` Rob Herring
2022-04-04 15:01 ` Hector Martin
2022-04-05 15:37 ` Sven Peter
2022-03-21 17:17 ` Alyssa Rosenzweig
2022-04-02 12:40 ` Sven Peter
2022-03-21 16:50 ` [PATCH 5/9] soc: apple: Add RTKit IPC library Sven Peter
2022-03-22 13:13 ` Arnd Bergmann
2022-03-22 17:41 ` Robin Murphy
2022-04-02 12:56 ` Sven Peter
2022-04-02 18:30 ` Arnd Bergmann
2022-04-03 10:45 ` Sven Peter
2022-03-22 17:23 ` Alyssa Rosenzweig
2022-04-02 12:50 ` Sven Peter
2022-03-23 11:19 ` Krzysztof Kozlowski
2022-04-02 13:51 ` Sven Peter
2022-04-02 16:08 ` Krzysztof Kozlowski
2022-04-04 15:02 ` Rob Herring
2022-04-04 15:47 ` Hector Martin
2022-03-21 16:50 ` [PATCH 6/9] nvme-apple: Add initial Apple SoC NVMe driver Sven Peter
2022-03-21 17:01 ` Keith Busch
2022-04-02 13:10 ` Sven Peter
2022-03-22 13:38 ` Arnd Bergmann
2022-04-02 13:34 ` Sven Peter
2022-04-02 13:58 ` Janne Grunau
2022-04-02 14:02 ` Sven Peter
2022-04-02 21:26 ` Arnd Bergmann
2022-03-24 6:16 ` Christoph Hellwig
2022-04-02 12:47 ` Sven Peter
2022-04-04 15:57 ` Hector Martin
2022-04-04 15:59 ` Christoph Hellwig
2022-04-04 16:03 ` Sven Peter
2022-04-04 16:05 ` hch
2022-04-04 16:05 ` Hector Martin
2022-04-04 18:29 ` Jens Axboe
2022-04-05 6:24 ` Christoph Hellwig
2022-03-21 16:50 ` [PATCH 7/9] nvme-apple: Serialize command issue Sven Peter
2022-03-24 6:16 ` Christoph Hellwig
2022-04-02 12:42 ` Sven Peter
2022-03-21 16:50 ` [PATCH 8/9] nvme-apple: Add support for multiple power domains Sven Peter
2022-03-21 16:50 ` [PATCH 9/9] nvme-apple: Add support for suspend/resume Sven Peter
2022-03-24 6:17 ` Christoph Hellwig
2022-03-22 17:26 ` [PATCH 0/9] Apple M1 (Pro/Max) NVMe driver Alyssa Rosenzweig
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=CAK8P3a19F8K0MvZV_R6HrmmR+WBsDge+u6U3iEVEjZ74i6+nEg@mail.gmail.com \
--to=arnd@arndb.de \
--cc=alyssa@rosenzweig.io \
--cc=axboe@fb.com \
--cc=devicetree@vger.kernel.org \
--cc=hch@lst.de \
--cc=kbusch@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=marcan@marcan.st \
--cc=maz@kernel.org \
--cc=robh+dt@kernel.org \
--cc=sagi@grimberg.me \
--cc=sven@svenpeter.dev \
/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).