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db59e1b6e4
Extract generic DMA setup code out of IORT, so it can be reused by VIOT. Keep it in drivers/acpi/arm64 for now, since it could break x86 platforms that haven't run this code so far, if they have invalid tables. Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/20210618152059.1194210-2-jean-philippe@linaro.org Signed-off-by: Joerg Roedel <jroedel@suse.de>
50 lines
1.4 KiB
C
50 lines
1.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/acpi.h>
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#include <linux/acpi_iort.h>
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#include <linux/device.h>
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#include <linux/dma-direct.h>
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void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
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{
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int ret;
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u64 end, mask;
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u64 dmaaddr = 0, size = 0, offset = 0;
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/*
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* If @dev is expected to be DMA-capable then the bus code that created
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* it should have initialised its dma_mask pointer by this point. For
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* now, we'll continue the legacy behaviour of coercing it to the
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* coherent mask if not, but we'll no longer do so quietly.
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*/
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if (!dev->dma_mask) {
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dev_warn(dev, "DMA mask not set\n");
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dev->dma_mask = &dev->coherent_dma_mask;
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}
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if (dev->coherent_dma_mask)
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size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
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else
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size = 1ULL << 32;
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ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size);
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if (ret == -ENODEV)
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ret = iort_dma_get_ranges(dev, &size);
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if (!ret) {
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/*
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* Limit coherent and dma mask based on size retrieved from
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* firmware.
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*/
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end = dmaaddr + size - 1;
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mask = DMA_BIT_MASK(ilog2(end) + 1);
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dev->bus_dma_limit = end;
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dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
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*dev->dma_mask = min(*dev->dma_mask, mask);
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}
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*dma_addr = dmaaddr;
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*dma_size = size;
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ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size);
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dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? " failed!" : "");
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}
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