diff mbox series

[v2,3/7] iommu/exynos: Set correct dma mask for SysMMU v5+

Message ID 20220710230603.13526-4-semen.protsenko@linaro.org
State Superseded
Headers show
Series iommu/exynos: Add basic support for SysMMU v7 | expand

Commit Message

Sam Protsenko July 10, 2022, 11:05 p.m. UTC 
SysMMU v5+ supports 36 bit physical address space. Set corresponding DMA
mask to avoid falling back to SWTLBIO usage in dma_map_single() because
of failed dma_capable() check.

The original code for this fix was suggested by Marek.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Co-developed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
Changes in v2:
  - Handled failed dma_set_mask() call
  - Replaced "Originally-by" tag by "Co-developed-by" + SoB tags

 drivers/iommu/exynos-iommu.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

Comments

Krzysztof Kozlowski July 12, 2022, 4:21 p.m. UTC | #1 
On 11/07/2022 01:05, Sam Protsenko wrote:
> SysMMU v5+ supports 36 bit physical address space. Set corresponding DMA
> mask to avoid falling back to SWTLBIO usage in dma_map_single() because
> of failed dma_capable() check.
> 
> The original code for this fix was suggested by Marek.
> 
> Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
> Co-developed-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>


Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>


Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index c85db9dab851..494f7d7aa9c5 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -646,6 +646,14 @@  static int exynos_sysmmu_probe(struct platform_device *pdev)
 		}
 	}
 
+	if (MMU_MAJ_VER(data->version) >= 5) {
+		ret = dma_set_mask(dev, DMA_BIT_MASK(36));
+		if (ret) {
+			dev_err(dev, "Unable to set DMA mask: %d\n", ret);
+			goto err_dma_set_mask;
+		}
+	}
+
 	/*
 	 * use the first registered sysmmu device for performing
 	 * dma mapping operations on iommu page tables (cpu cache flush)
@@ -657,6 +665,8 @@  static int exynos_sysmmu_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_dma_set_mask:
+	iommu_device_unregister(&data->iommu);
 err_iommu_register:
 	iommu_device_sysfs_remove(&data->iommu);
 	return ret;