WSL2-Linux-Kernel/drivers/acpi/arm64/dma.c

51 строка
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/acpi.h>
#include <linux/acpi_iort.h>
#include <linux/device.h>
#include <linux/dma-direct.h>
void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
{
int ret;
u64 end, mask;
u64 dmaaddr = 0, size = 0, offset = 0;
/*
* If @dev is expected to be DMA-capable then the bus code that created
* it should have initialised its dma_mask pointer by this point. For
* now, we'll continue the legacy behaviour of coercing it to the
* coherent mask if not, but we'll no longer do so quietly.
*/
if (!dev->dma_mask) {
dev_warn(dev, "DMA mask not set\n");
dev->dma_mask = &dev->coherent_dma_mask;
}
if (dev->coherent_dma_mask)
size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
else
size = 1ULL << 32;
ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size);
if (ret == -ENODEV)
ret = iort_dma_get_ranges(dev, &size);
if (!ret) {
/*
* Limit coherent and dma mask based on size retrieved from
* firmware.
*/
end = dmaaddr + size - 1;
mask = DMA_BIT_MASK(ilog2(end) + 1);
dev->bus_dma_limit = end;
dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
*dev->dma_mask = min(*dev->dma_mask, mask);
}
*dma_addr = dmaaddr;
*dma_size = size;
ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size);
dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? " failed!" : "");
}