Hello.
On 09/14/2013 10:33 PM, Guennadi Liakhovetski wrote:
From: Max Filippov <max.filip...@cogentembedded.com>
Add support for HPB-DMAC found in Renesas R-Car SoCs, using 'shdma-base' DMA
driver framework.
Based on the original patch by Phil Edworthy <phil.edwor...@renesas.com>.
Signed-off-by: Max Filippov <max.filip...@cogentembedded.com>
[Sergei: removed useless #include, sorted #include's, fixed HPB_DMA_TCR_MAX,
fixed formats and removed line breaks in the dev_dbg() calls, rephrased and
added IRQ # to the shdma_request_irq() failure message, added MODULE_AUTHOR(),
removed '__init'/'__exit' annotations from the probe()/remove() methods, removed
'__initdata' annotation from 'hpb_dmae_driver', fixed guard macro name in the
header file, fixed #define ASYNCRSTR_ASRST20, added #define ASYNCRSTR_ASRST24,
added the necessary runtime PM calls to the probe() and remove() methods,
handled errors returned by dma_async_device_register(), beautified comments
and #define's.]
Signed-off-by: Sergei Shtylyov <sergei.shtyl...@cogentembedded.com>
---
[snip]
Index: slave-dma/drivers/dma/sh/rcar-hpbdma.c
===================================================================
--- /dev/null
+++ slave-dma/drivers/dma/sh/rcar-hpbdma.c
@@ -0,0 +1,655 @@
[snip]
+static int hpb_dmae_chan_probe(struct hpb_dmae_device *hpbdev, int id)
+{
+ struct shdma_dev *sdev = &hpbdev->shdma_dev;
+ struct platform_device *pdev =
+ to_platform_device(hpbdev->shdma_dev.dma_dev.dev);
+ struct hpb_dmae_chan *new_hpb_chan;
+ struct shdma_chan *schan;
+
+ /* Alloc channel */
+ new_hpb_chan = devm_kzalloc(&pdev->dev,
+ sizeof(struct hpb_dmae_chan), GFP_KERNEL);
+ if (!new_hpb_chan) {
+ dev_err(hpbdev->shdma_dev.dma_dev.dev,
+ "No free memory for allocating DMA channels!\n");
+ return -ENOMEM;
+ }
+
+ schan = &new_hpb_chan->shdma_chan;
A suggestion for an incremental patch - you might want to initialise the
max_xfer_len field like
schan->max_xfer_len = 64 * 1024 * 1024 - 1;
IIRC, the HPB-DMAC's maximum transfer length is 16 MiB, without -1. You
probably mixed it with LBSC-DMAC which is indeed capable of 64 MiB.
because if it isn't initialised your max transfer length will be 4k,
which will hurt your performance. I think you should get a better
throughput after that
OK, note taken. We'll look into it.
WBR, Sergei
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