linuxdebug/arch/loongarch/kernel/dma.c

31 lines
709 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <linux/acpi.h>
#include <linux/dma-direct.h>
void acpi_arch_dma_setup(struct device *dev)
{
int ret;
u64 mask, end = 0;
const struct bus_dma_region *map = NULL;
ret = acpi_dma_get_range(dev, &map);
if (!ret && map) {
const struct bus_dma_region *r = map;
for (end = 0; r->size; r++) {
if (r->dma_start + r->size - 1 > end)
end = r->dma_start + r->size - 1;
}
mask = DMA_BIT_MASK(ilog2(end) + 1);
dev->bus_dma_limit = end;
dev->dma_range_map = map;
dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
*dev->dma_mask = min(*dev->dma_mask, mask);
}
}