[PATCH 21/63] dmaengine: ste_dma40: Don't configure runtime configurable setup during allocate

Lee Jones lee.jones at linaro.org
Wed May 8 11:24:58 EDT 2013


On Fri, 03 May 2013, Linus Walleij wrote:

> On Fri, May 3, 2013 at 4:32 PM, Lee Jones <lee.jones at linaro.org> wrote:
> 
> > Using the dmaengine API, allocating and configuring a channel are two
> > separate actions. Here we're removing logical channel configuration from
> > the channel allocating routines.
> >
> > Cc: Vinod Koul <vinod.koul at intel.com>
> > Cc: Dan Williams <djbw at fb.com>
> > Cc: Per Forlin <per.forlin at stericsson.com>
> > Cc: Rabin Vincent <rabin at rab.in>
> > Signed-off-by: Lee Jones <lee.jones at linaro.org>
> (...)
> 
> > @@ -2024,6 +2024,9 @@ static int d40_config_memcpy(struct d40_chan *d40c)
> >                 d40c->dma_cfg = dma40_memcpy_conf_log;
> >                 d40c->dma_cfg.dev_type = dma40_memcpy_channels[d40c->chan.chan_id];
> >
> > +               d40_log_cfg(&d40c->dma_cfg,
> > +                           &d40c->log_def.lcsp1, &d40c->log_def.lcsp3);
> > +
> 
> So it only gets configured for memcpy now?
> 
> What happens if you use a logical channel for a device transfer?
> 
> Where will that be configured?

In d40_set_runtime_config()

> /* Fill in register values */
> if (chan_is_logical(d40c))
> 	d40_log_cfg(cfg, &d40c->log_def.lcsp1, &d40c->log_def.lcsp3);
> else
> 	d40_phy_cfg(cfg, &d40c->src_def_cfg, &d40c->dst_def_cfg);

> Have you tested this combo?

Yes. All ux500 based DMA use logical channels.

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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