From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
To: Sricharan R <sricharan@codeaurora.org>, vkoul@kernel.org
Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-arm-msm@vger.kernel.org
Subject: Re: [PATCH] dmaengine: qcom-bam: fix circular buffer handling
Date: Tue, 18 Jun 2019 17:50:06 +0100 [thread overview]
Message-ID: <31574ef2-d675-bb36-08d1-18b756ebd29e@linaro.org> (raw)
In-Reply-To: <a50066ac-be85-6706-e7f3-f1069fd0dd0b@codeaurora.org>
On 18/06/2019 17:27, Sricharan R wrote:
> The Macro's expect that buffer size is power of 2. So we are infact passing the actual correct
> size ( MAX_DESCRIPTORS + 1 = 4096)
This will make the circular buffer macros happy but question is that do
we actually have that many descriptor buffers?
This is what is in the driver:
#define BAM_DESC_FIFO_SIZE SZ_32K
#define MAX_DESCRIPTORS (BAM_DESC_FIFO_SIZE / sizeof(struct bam_desc_hw)
- 1)
#define BAM_FIFO_SIZE (SZ_32K - 8)
Wouldn't having MAX_DESCRIPTORS + 1 = 4096 lead to overflow the actual
descriptor memory size of (SZ_32K - 8) ?
--srini
next prev parent reply other threads:[~2019-06-18 16:50 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-14 14:20 [PATCH] dmaengine: qcom-bam: fix circular buffer handling Srinivas Kandagatla
2019-06-14 19:43 ` Andy Gross
2019-06-18 4:53 ` Vinod Koul
2019-06-18 7:13 ` Sricharan R
2019-06-18 14:49 ` Srinivas Kandagatla
2019-06-18 14:50 ` Srinivas Kandagatla
2019-06-18 14:56 ` Sricharan R
2019-06-18 15:12 ` Srinivas Kandagatla
2019-06-18 16:27 ` Sricharan R
2019-06-18 16:50 ` Srinivas Kandagatla [this message]
2019-06-19 17:50 ` Sricharan R
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