On 04-11-22, 11:17, Lizhi Hou wrote:
> On 11/4/22 10:57, Vinod Koul wrote:
> > On 04-11-22, 09:57, Lizhi Hou wrote:
> > > On 11/4/22 07:32, Vinod Koul wrote:
> > > > On 25-10-22, 10:57, Lizhi Hou wrote:
> > > > > +static inline int xdma_write_reg(struct xdma_device *xdev, u32 base, u32 reg,
> > > > > + u32 val)
> > > > > +{
> > > > > + return regmap_write(xdev->regmap, base + reg, val);
> > > > > +}
> > > > Do you really need one more level indirection?
> > > Do you mean using readl / writel instead of regmap_* here?
> > Nope, I refer to using regmap_write() intead of xdma_write_reg()
>
> Ok. As you mentioned below,
>
> why not move err into xdma_write_reg(), rather than adding in each
> helper!
>
> If I use regmap_write() directly, I will not be able to move err into
> xdma_write_reg(). Having a inline function might be useful to add debug
> code. May I keep xdma_write_reg()?
Okay, either way if xdma_write_reg() is doing only regmap_write() then
no, if it has extra logic like logging on error etc then it makes sense
> > > > > +failed:
> > > > > + xdma_free_desc(&sw_desc->vdesc);
> > > > who will free sw_desc here?
> > > sw_desc is freed by xdma_free_desc(). xdma_free_desc() is virt-dma callback
> > > it converts struct virt_dma_desc pointer to driver sw_desc pointer and free
> > > the whole thing.
> > IN case of error, you are returning NULL, so allocated descriptor leaks
>
> I meant the descriptor is freed inside xdma_free_desc() which is called
> before 'return NULL'.
>
> xdma_free_desc(struct virt_dma_desc *vdesc)
>
> {
>
> sw_desc = to_xdma_desc(vdesc);
>
> .....
>
> kfree(sw_desc);
>
> }
ok
> > > > > +#ifndef _PLATDATA_AMD_XDMA_H
> > > > > +#define _PLATDATA_AMD_XDMA_H
> > > > > +
> > > > > +#include <linux/dmaengine.h>
> > > > > +
> > > > > +/**
> > > > > + * struct xdma_chan_info - DMA channel information
> > > > > + * This information is used to match channel when request dma channel
> > > > > + * @dir: Channel transfer direction
> > > > > + */
> > > > > +struct xdma_chan_info {
> > > > > + enum dma_transfer_direction dir;
> > > > > +};
> > > > > +
> > > > > +#define XDMA_FILTER_PARAM(chan_info) ((void *)(chan_info))
> > > > > +
> > > > > +struct dma_slave_map;
> > > > > +
> > > > > +/**
> > > > > + * struct xdma_platdata - platform specific data for XDMA engine
> > > > > + * @max_dma_channels: Maximum dma channels in each direction
> > > > > + */
> > > > > +struct xdma_platdata {
> > > > > + u32 max_dma_channels;
> > > > > + u32 device_map_cnt;
> > > > > + struct dma_slave_map *device_map;
> > > > > +};
> > > > why do you need this plat data
> > > max_dma_channels is used to specify the maximum dma channels will be used.
> > What is the device mode, who creates this dma device, devicetree or
> > something else?
>
> This dma engine is on PCI device (exposed on PCI BAR). Thus, the pci device
> driver creates this dma device.
So it is a platform_device type? Why not make it something like auxdev?
--
~Vinod
