From: Phil Chang <phil.chang@mediatek.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alix Wu <alix.wu@mediatek.com>,
YJ Chiang <yj.chiang@mediatek.com>,
Phil Chang <phil.chang@mediatek.com>,
linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: Re: [PATCH] [PATCH] ARM64: Setup DMA32 zone size by bootargs
Date: Thu, 24 Sep 2020 22:15:14 +0800 [thread overview]
Message-ID: <20200924141514.23930-1-phil.chang@mediatek.com> (raw)
In-Reply-To: <20200916133324.6280-1-phil.chang@mediatek.com>
Actually, In a embedded system with 3GB memory, the memory bus width is not the same among the 3GB.
(The first 2GB is 48-bit wide, and the latter 1GB is 16-bit wide.)
For memory throughput reason of hardware IPs, we need allocate memory from the first 2GB for
the hardware IPs. And that is why we setup the first 2GB as DMA_ZONE, and use GFP_DMA to allocate
memory from the range.
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next prev parent reply other threads:[~2020-09-24 14:17 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-15 15:08 [PATCH] [PATCH] ARM64: Setup DMA32 zone size by bootargs Phil Chang
2020-09-15 16:13 ` Catalin Marinas
2020-09-15 16:18 ` Mike Rapoport
2020-09-15 17:48 ` David Woodhouse
2020-09-16 7:22 ` Phil Chang
2020-09-16 8:37 ` Christoph Hellwig
2020-09-16 13:33 ` Phil Chang
2020-09-16 14:56 ` Catalin Marinas
2020-09-24 14:15 ` Phil Chang [this message]
2020-09-25 9:11 ` Catalin Marinas
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