linux/arch/m68k/apollo/dma.c

51 lines
1.2 KiB
C

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/kd.h>
#include <linux/tty.h>
#include <linux/console.h>
#include <asm/setup.h>
#include <asm/bootinfo.h>
#include <asm/system.h>
#include <asm/pgtable.h>
#include <asm/apollodma.h>
#include <asm/io.h>
/* note only works for 16 Bit 1 page DMA's */
static unsigned short next_free_xlat_entry=0;
unsigned short dma_map_page(unsigned long phys_addr,int count,int type) {
unsigned long page_aligned_addr=phys_addr & (~((1<<12)-1));
unsigned short start_map_addr=page_aligned_addr >> 10;
unsigned short free_xlat_entry, *xlat_map_entry;
int i;
free_xlat_entry=next_free_xlat_entry;
for(i=0,xlat_map_entry=addr_xlat_map+(free_xlat_entry<<2);i<8;i++,xlat_map_entry++) {
#if 0
printk("phys_addr: %x, page_aligned_addr: %x, start_map_addr: %x\n",phys_addr,page_aligned_addr,start_map_addr+i);
#endif
out_be16(xlat_map_entry, start_map_addr+i);
}
next_free_xlat_entry+=2;
if(next_free_xlat_entry>125)
next_free_xlat_entry=0;
#if 0
printk("next_free_xlat_entry: %d\n",next_free_xlat_entry);
#endif
return free_xlat_entry<<10;
}
void dma_unmap_page(unsigned short dma_addr) {
return ;
}