The ADMA base and page address are represented using a 64-bit variable. To accurately derive the exact ADMA page number provided from the DT properties, use the div_u64() to divide the address difference between adma page and base address by the page offset.
This change fixes the below error "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] undefined! ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe': tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"
Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page") Cc: stable@vger.kernel.org Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3-lkp@intel.com/ Signed-off-by: Mohan Kumar D mkumard@nvidia.com Reviewed-by: Jon Hunter jonathanh@nvidia.com Acked-by: Thierry Reding treding@nvidia.com --- drivers/dma/tegra210-adma.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c index 6896da8ac7ef..a0bd4822ed80 100644 --- a/drivers/dma/tegra210-adma.c +++ b/drivers/dma/tegra210-adma.c @@ -887,7 +887,8 @@ static int tegra_adma_probe(struct platform_device *pdev) const struct tegra_adma_chip_data *cdata; struct tegra_adma *tdma; struct resource *res_page, *res_base; - int ret, i, page_no; + u64 page_no, page_offset; + int ret, i;
cdata = of_device_get_match_data(&pdev->dev); if (!cdata) { @@ -914,10 +915,16 @@ static int tegra_adma_probe(struct platform_device *pdev)
res_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "global"); if (res_base) { - page_no = (res_page->start - res_base->start) / cdata->ch_base_offset; - if (page_no <= 0) + if (WARN_ON(res_page->start <= res_base->start)) return -EINVAL; - tdma->ch_page_no = page_no - 1; + + page_offset = res_page->start - res_base->start; + page_no = div_u64(page_offset, cdata->ch_base_offset); + + if (WARN_ON(page_no == 0)) + return -EINVAL; + + tdma->ch_page_no = lower_32_bits(page_no) - 1; tdma->base_addr = devm_ioremap_resource(&pdev->dev, res_base); if (IS_ERR(tdma->base_addr)) return PTR_ERR(tdma->base_addr);