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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm64/mm/dma-mapping.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/arm64/mm/dma-mapping.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c new file mode 100644 index 000000000..5240f6aca --- /dev/null +++ b/arch/arm64/mm/dma-mapping.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 ARM Ltd. + * Author: Catalin Marinas <catalin.marinas@arm.com> + */ + +#include <linux/gfp.h> +#include <linux/cache.h> +#include <linux/dma-map-ops.h> +#include <linux/iommu.h> +#include <xen/xen.h> + +#include <asm/cacheflush.h> +#include <asm/xen/xen-ops.h> + +void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, + enum dma_data_direction dir) +{ + unsigned long start = (unsigned long)phys_to_virt(paddr); + + dcache_clean_poc(start, start + size); +} + +void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, + enum dma_data_direction dir) +{ + unsigned long start = (unsigned long)phys_to_virt(paddr); + + if (dir == DMA_TO_DEVICE) + return; + + dcache_inval_poc(start, start + size); +} + +void arch_dma_prep_coherent(struct page *page, size_t size) +{ + unsigned long start = (unsigned long)page_address(page); + + /* + * The architecture only requires a clean to the PoC here in order to + * meet the requirements of the DMA API. However, some vendors (i.e. + * Qualcomm) abuse the DMA API for transferring buffers from the + * non-secure to the secure world, resetting the system if a non-secure + * access shows up after the buffer has been transferred: + * + * https://lore.kernel.org/r/20221114110329.68413-1-manivannan.sadhasivam@linaro.org + * + * Using clean+invalidate appears to make this issue less likely, but + * the drivers themselves still need fixing as the CPU could issue a + * speculative read from the buffer via the linear mapping irrespective + * of the cache maintenance we use. Once the drivers are fixed, we can + * relax this to a clean operation. + */ + dcache_clean_inval_poc(start, start + size); +} + +#ifdef CONFIG_IOMMU_DMA +void arch_teardown_dma_ops(struct device *dev) +{ + dev->dma_ops = NULL; +} +#endif + +void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, + const struct iommu_ops *iommu, bool coherent) +{ + int cls = cache_line_size_of_cpu(); + + WARN_TAINT(!coherent && cls > ARCH_DMA_MINALIGN, + TAINT_CPU_OUT_OF_SPEC, + "%s %s: ARCH_DMA_MINALIGN smaller than CTR_EL0.CWG (%d < %d)", + dev_driver_string(dev), dev_name(dev), + ARCH_DMA_MINALIGN, cls); + + dev->dma_coherent = coherent; + if (iommu) + iommu_setup_dma_ops(dev, dma_base, dma_base + size - 1); + + xen_setup_dma_ops(dev); +} |