linux/linux-5.4.31/arch/powerpc/kernel/prom_parse.c

35 lines
910 B
C

// SPDX-License-Identifier: GPL-2.0
#undef DEBUG
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/etherdevice.h>
#include <linux/of_address.h>
#include <asm/prom.h>
void of_parse_dma_window(struct device_node *dn, const __be32 *dma_window,
unsigned long *busno, unsigned long *phys,
unsigned long *size)
{
u32 cells;
const __be32 *prop;
/* busno is always one cell */
*busno = of_read_number(dma_window, 1);
dma_window++;
prop = of_get_property(dn, "ibm,#dma-address-cells", NULL);
if (!prop)
prop = of_get_property(dn, "#address-cells", NULL);
cells = prop ? of_read_number(prop, 1) : of_n_addr_cells(dn);
*phys = of_read_number(dma_window, cells);
dma_window += cells;
prop = of_get_property(dn, "ibm,#dma-size-cells", NULL);
cells = prop ? of_read_number(prop, 1) : of_n_size_cells(dn);
*size = of_read_number(dma_window, cells);
}