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From: noman pouigt <variksla@gmail.com>
To: linux-kernel@vger.kernel.org,
	kernelnewbies <kernelnewbies@kernelnewbies.org>
Subject: Mapping ram memory using ioremap
Date: Wed, 11 May 2022 16:00:14 -0700	[thread overview]
Message-ID: <CAES_P+-khQGqec2_xqVEU4m0b9WscvLUinQmPXi6zX_P4mP+hw@mail.gmail.com> (raw)

We are using part of DRAM as shared memory
between DSP and SoC. However, DSP
can only access higher 1GB of DRAM.

In order to map the aforementioned memory
I tried using ioremap and it blurted out the
warning as mentioned in this article.
https://lwn.net/Articles/409700/

What is the alternative to using ioremap to
map specific RAM memory region for use
in the driver as shared memory?

I tried memremap + reserved memory as well
and it failed.

WARNING: multiple messages have this Message-ID (diff)
From: noman pouigt <variksla@gmail.com>
To: linux-kernel@vger.kernel.org,
	 kernelnewbies <kernelnewbies@kernelnewbies.org>
Subject: Mapping ram memory using ioremap
Date: Wed, 11 May 2022 16:00:14 -0700	[thread overview]
Message-ID: <CAES_P+-khQGqec2_xqVEU4m0b9WscvLUinQmPXi6zX_P4mP+hw@mail.gmail.com> (raw)

We are using part of DRAM as shared memory
between DSP and SoC. However, DSP
can only access higher 1GB of DRAM.

In order to map the aforementioned memory
I tried using ioremap and it blurted out the
warning as mentioned in this article.
https://lwn.net/Articles/409700/

What is the alternative to using ioremap to
map specific RAM memory region for use
in the driver as shared memory?

I tried memremap + reserved memory as well
and it failed.

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             reply	other threads:[~2022-05-11 23:00 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-11 23:00 noman pouigt [this message]
2022-05-11 23:00 ` Mapping ram memory using ioremap noman pouigt

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