Commit 54541815 authored Sep 13, 2018 by Niklas Söderlund Committed by Ulf Hansson Oct 08, 2018

mmc: renesas_sdhi_internal_dmac: set scatter/gather max segment size



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 <geert+renesas@glider.be>
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
[wsa: simplified some logic after validating intended dma_parms life cycle
      and added comment]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

parent 07bafc1e

drivers/mmc/host/renesas_sdhi_internal_dmac.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -308,12 +308,20 @@ 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);
		}