From: Niklas Söderlund <[email protected]> Fix warning when running with CONFIG_DMA_API_DEBUG_SG=y by allocating a device_dma_parameters structure and filling in the max segment size. The size used is the result of a discussion with Renesas hardware engineers and unfortunately not found in the datasheet.
renesas_sdhi_internal_dmac ee140000.sd: DMA-API: mapping sg segment longer than device claims to support [len=126976] [max=65536] Reported-by: Geert Uytterhoeven <[email protected]> Signed-off-by: Niklas Söderlund <[email protected]> [wsa: simplified some logic after validating intended dma_parms life cycle and added comment] Signed-off-by: Wolfram Sang <[email protected]> --- After discussing with DMA maintainers [1], this really seems the intended way of using dma_parms. Took Niklas patch V2 and simplified the logic a bit more given the information from above (but I'll still tackle the dangling pointer issue in the DMA core seperately). [1] https://www.spinics.net/lists/iommu/msg29861.html drivers/mmc/host/renesas_sdhi_internal_dmac.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/mmc/host/renesas_sdhi_internal_dmac.c b/drivers/mmc/host/renesas_sdhi_internal_dmac.c index ca0b43973769..e0823acaa3c2 100644 --- a/drivers/mmc/host/renesas_sdhi_internal_dmac.c +++ b/drivers/mmc/host/renesas_sdhi_internal_dmac.c @@ -309,12 +309,20 @@ static const struct soc_device_attribute gen3_soc_whitelist[] = { static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev) { const struct soc_device_attribute *soc = soc_device_match(gen3_soc_whitelist); + struct device *dev = &pdev->dev; if (!soc) return -ENODEV; global_flags |= (unsigned long)soc->data; + dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms), GFP_KERNEL); + if (!dev->dma_parms) + return -ENOMEM; + + /* value is max of SD_SECCNT. Confirmed by HW engineers */ + dma_set_max_seg_size(dev, 0xffffffff); + return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops); } -- 2.11.0
