diff options
Diffstat (limited to 'arch/powerpc/kernel/prom_parse.c')
| -rw-r--r-- | arch/powerpc/kernel/prom_parse.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/prom_parse.c b/arch/powerpc/kernel/prom_parse.c new file mode 100644 index 000000000..9cb7f88df --- /dev/null +++ b/arch/powerpc/kernel/prom_parse.c @@ -0,0 +1,34 @@ +// 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); +} |