[1/5] dmaengine: edma: Implement protection for invalid max_burst

Message ID 20170912104424.18495-2-peter.ujfalusi@ti.com
State New
Headers show
Series
  • dmaengine: core/edma/omap-dma: maximum SG len reporting
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Commit Message

Peter Ujfalusi Sept. 12, 2017, 10:44 a.m.
´╗┐Set the device's max_burst to 32767 (CIDX is 16bit signed value) so clients
can take this into consideration when setting up the trasnfer.

During slave transfer preparation check if the requested maxburst is valid.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/dma/edma.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Vinod Koul Sept. 21, 2017, 5:10 p.m. | #1
On Tue, Sep 12, 2017 at 01:44:20PM +0300, Peter Ujfalusi wrote:
> Set the device's max_burst to 32767 (CIDX is 16bit signed value) so clients
> can take this into consideration when setting up the trasnfer.

/s/trasnfer/transfer

> 
> During slave transfer preparation check if the requested maxburst is valid.
> 
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> ---
>  drivers/dma/edma.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
> index 3879f80a4815..6970355abdc9 100644
> --- a/drivers/dma/edma.c
> +++ b/drivers/dma/edma.c
> @@ -891,6 +891,10 @@ static int edma_slave_config(struct dma_chan *chan,
>  	    cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
>  		return -EINVAL;
>  
> +	if (cfg->src_maxburst > chan->device->max_burst ||
> +	    cfg->dst_maxburst > chan->device->max_burst)
> +		return -EINVAL;
> +
>  	memcpy(&echan->cfg, cfg, sizeof(echan->cfg));
>  
>  	return 0;
> @@ -1855,6 +1859,7 @@ static void edma_dma_init(struct edma_cc *ecc, bool legacy_mode)
>  	s_ddev->dst_addr_widths = EDMA_DMA_BUSWIDTHS;
>  	s_ddev->directions |= (BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV));
>  	s_ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
> +	s_ddev->max_burst = SZ_32K - 1; /* CIDX: 16bit signed */
>  
>  	s_ddev->dev = ecc->dev;
>  	INIT_LIST_HEAD(&s_ddev->channels);
> -- 
> 2.14.1
> 
> 
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
> 
>

Patch

diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index 3879f80a4815..6970355abdc9 100644
--- a/drivers/dma/edma.c
+++ b/drivers/dma/edma.c
@@ -891,6 +891,10 @@  static int edma_slave_config(struct dma_chan *chan,
 	    cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
 		return -EINVAL;
 
+	if (cfg->src_maxburst > chan->device->max_burst ||
+	    cfg->dst_maxburst > chan->device->max_burst)
+		return -EINVAL;
+
 	memcpy(&echan->cfg, cfg, sizeof(echan->cfg));
 
 	return 0;
@@ -1855,6 +1859,7 @@  static void edma_dma_init(struct edma_cc *ecc, bool legacy_mode)
 	s_ddev->dst_addr_widths = EDMA_DMA_BUSWIDTHS;
 	s_ddev->directions |= (BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV));
 	s_ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+	s_ddev->max_burst = SZ_32K - 1; /* CIDX: 16bit signed */
 
 	s_ddev->dev = ecc->dev;
 	INIT_LIST_HEAD(&s_ddev->channels);