RE: [EXT] Re: [PATCH V2 1/1] dmaengine: fsl-edma: support edma memcpy

From: Joy Zou
Date: Tue Oct 19 2021 - 01:39:49 EST



-----Original Message-----
From: Vinod Koul <vkoul@xxxxxxxxxx>
Sent: 2021年10月18日 14:40
To: Joy Zou <joy.zou@xxxxxxx>
Cc: Robin Gong <yibin.gong@xxxxxxx>; dmaengine@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Subject: [EXT] Re: [PATCH V2 1/1] dmaengine: fsl-edma: support edma memcpy

Caution: EXT Email

On 11-10-21, 18:36, Joy Zou wrote:
> add memcpy in edma.

can you describe the changes?
The edma has the capability to transfer data by software trigger so that it could be used for memory copy. Enable MEMCPY for edma driver and it could be test directly by dmatest.

>
> Signed-off-by: Joy Zou <joy.zou@xxxxxxx>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>

how is the support reported by the bot?
Robot report warning on v1, will remove 'Reported-by' tag and move such Information in change history in v3.

> ---
> drivers/dma/fsl-edma-common.c | 32 +++++++++++++++++++++++++++++++-
> drivers/dma/fsl-edma-common.h | 4 ++++
> drivers/dma/fsl-edma.c | 7 +++++++
> 3 files changed, 42 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma/fsl-edma-common.c
> b/drivers/dma/fsl-edma-common.c index 930ae268c497..8a451855c3be
> 100644
> --- a/drivers/dma/fsl-edma-common.c
> +++ b/drivers/dma/fsl-edma-common.c
> @@ -348,7 +348,7 @@ static void fsl_edma_set_tcd_regs(struct fsl_edma_chan *fsl_chan,
> struct fsl_edma_engine *edma = fsl_chan->edma;
> struct edma_regs *regs = &fsl_chan->edma->regs;
> u32 ch = fsl_chan->vchan.chan.chan_id;
> -
> + u16 csr = 0;

blank line would look better after this
Will fixed in v3
> /*
> * TCD parameters are stored in struct fsl_edma_hw_tcd in little
> * endian format. However, we need to load the TCD registers in
> @@ -373,6 +373,12 @@ static void fsl_edma_set_tcd_regs(struct fsl_edma_chan *fsl_chan,
> edma_writel(edma, (s32)tcd->dlast_sga,
> &regs->tcd[ch].dlast_sga);
>
> + if (fsl_chan->is_sw) {
> + csr = le16_to_cpu(tcd->csr);
> + csr |= EDMA_TCD_CSR_START;
> + tcd->csr = cpu_to_le16(csr);
> + }
> +
> edma_writew(edma, (s16)tcd->csr, &regs->tcd[ch].csr); }
>
> @@ -587,6 +593,29 @@ struct dma_async_tx_descriptor
> *fsl_edma_prep_slave_sg( }
> EXPORT_SYMBOL_GPL(fsl_edma_prep_slave_sg);
>
> +struct dma_async_tx_descriptor *fsl_edma_prep_memcpy(
> + struct dma_chan *chan, dma_addr_t dma_dst,
> + dma_addr_t dma_src, size_t len, unsigned long flags) {
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct fsl_edma_desc *fsl_desc;
> +
> + fsl_desc = fsl_edma_alloc_desc(fsl_chan, 1);
> + if (!fsl_desc)
> + return NULL;
> + fsl_desc->iscyclic = false;
> +
> + fsl_chan->is_sw = true;
> +
> + /* To match with copy_align and max_seg_size so 1 tcd is enough */
> + fsl_edma_fill_tcd(fsl_desc->tcd[0].vtcd, dma_src, dma_dst,
> + EDMA_TCD_ATTR_SSIZE_32BYTE | EDMA_TCD_ATTR_DSIZE_32BYTE,
> + 32, len, 0, 1, 1, 32, 0, true, true, false);
> +
> + return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
> +} EXPORT_SYMBOL_GPL(fsl_edma_prep_memcpy);
> +
> void fsl_edma_xfer_desc(struct fsl_edma_chan *fsl_chan) {
> struct virt_dma_desc *vdesc;
> @@ -652,6 +681,7 @@ void fsl_edma_free_chan_resources(struct dma_chan *chan)
> vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
> dma_pool_destroy(fsl_chan->tcd_pool);
> fsl_chan->tcd_pool = NULL;
> + fsl_chan->is_sw = false;
> }
> EXPORT_SYMBOL_GPL(fsl_edma_free_chan_resources);
>
> diff --git a/drivers/dma/fsl-edma-common.h
> b/drivers/dma/fsl-edma-common.h index ec1169741de1..004ec4a6bc86
> 100644
> --- a/drivers/dma/fsl-edma-common.h
> +++ b/drivers/dma/fsl-edma-common.h
> @@ -121,6 +121,7 @@ struct fsl_edma_chan {
> struct fsl_edma_desc *edesc;
> struct dma_slave_config cfg;
> u32 attr;
> + bool is_sw;

what does is_sw mean?
The 'is_sw' mean whether the edma request is triggered by software.
> struct dma_pool *tcd_pool;
> dma_addr_t dma_dev_addr;
> u32 dma_dev_size;
> @@ -240,6 +241,9 @@ struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg(
> struct dma_chan *chan, struct scatterlist *sgl,
> unsigned int sg_len, enum dma_transfer_direction direction,
> unsigned long flags, void *context);
> +struct dma_async_tx_descriptor *fsl_edma_prep_memcpy(
> + struct dma_chan *chan, dma_addr_t dma_dst, dma_addr_t dma_src,
> + size_t len, unsigned long flags);
> void fsl_edma_xfer_desc(struct fsl_edma_chan *fsl_chan); void
> fsl_edma_issue_pending(struct dma_chan *chan); int
> fsl_edma_alloc_chan_resources(struct dma_chan *chan); diff --git
> a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c index
> 90bb72af306c..76cbf54aec58 100644
> --- a/drivers/dma/fsl-edma.c
> +++ b/drivers/dma/fsl-edma.c
> @@ -17,6 +17,7 @@
> #include <linux/of_address.h>
> #include <linux/of_irq.h>
> #include <linux/of_dma.h>
> +#include <linux/dma-mapping.h>
>
> #include "fsl-edma-common.h"
>
> @@ -372,6 +373,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
> dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
> dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
> dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
> + dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
>
> fsl_edma->dma_dev.dev = &pdev->dev;
> fsl_edma->dma_dev.device_alloc_chan_resources
> @@ -381,6 +383,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
> fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
> fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
> fsl_edma->dma_dev.device_prep_dma_cyclic =
> fsl_edma_prep_dma_cyclic;
> + fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
> fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
> fsl_edma->dma_dev.device_pause = fsl_edma_pause;
> fsl_edma->dma_dev.device_resume = fsl_edma_resume; @@ -392,6
> +395,10 @@ static int fsl_edma_probe(struct platform_device *pdev)
> fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
> fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) |
> BIT(DMA_MEM_TO_DEV);
>
> + fsl_edma->dma_dev.copy_align = DMAENGINE_ALIGN_32_BYTES;
> + /* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
> + dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);
> +
> platform_set_drvdata(pdev, fsl_edma);
>
> ret = dma_async_device_register(&fsl_edma->dma_dev);
> --
> 2.25.1

--
~Vinod