projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 57bbb53e BJ |
1 | /* |
| 2 | * code to manage AT bus | |
| 3 | * @(#)isa.c 1.1 (Berkeley) %G% | |
| 4 | */ | |
| 5 | ||
| 6 | #include "param.h" | |
| 7 | #include "systm.h" | |
| 8 | #include "conf.h" | |
| 9 | #include "file.h" | |
| 10 | #include "dir.h" | |
| 11 | #include "user.h" | |
| 12 | #include "buf.h" | |
| 13 | #include "vm.h" | |
| 14 | #include "uio.h" | |
| 15 | #include "machine/pte.h" | |
| 16 | ||
| 17 | /* stuff needed for virtual to physical calculations */ | |
| 18 | extern char Sysbase; | |
| 19 | static unsigned long sbase = (unsigned long) &Sysbase; | |
| 20 | ||
| 21 | struct buf *dma_bounce[8]; | |
| 22 | #define MAXDMASZ 512 | |
| 23 | ||
| 24 | /* XXX temporary */ | |
| 25 | kernel_space(x) | |
| 26 | unsigned long x; | |
| 27 | { | |
| 28 | if ((x >= sbase) & (x < sbase + 0x800000)) return 1; | |
| 29 | else return 0; | |
| 30 | } | |
| 31 | ||
| 32 | ||
| 33 | /****************************************************************************/ | |
| 34 | /* at_dma */ | |
| 35 | /* set up DMA read/write operation and virtual address addr for nbytes */ | |
| 36 | /****************************************************************************/ | |
| 37 | at_dma(read,addr,nbytes, chan) | |
| 38 | int read; | |
| 39 | unsigned long addr; | |
| 40 | int nbytes; | |
| 41 | { | |
| 42 | unsigned long phys; | |
| 43 | int s,raw; | |
| 44 | caddr_t bounce; | |
| 45 | ||
| 46 | if (kernel_space(addr)) raw = 0; | |
| 47 | else raw = 1; | |
| 48 | ||
| 49 | if(raw) { | |
| 50 | if (dma_bounce[chan] == 0) | |
| 51 | dma_bounce[chan] = geteblk(MAXDMASZ); | |
| 52 | bounce = dma_bounce[chan]->b_un.b_addr; | |
| 53 | } | |
| 54 | ||
| 55 | /* copy bounce buffer on write */ | |
| 56 | if (raw && !read) bcopy(addr,bounce,nbytes); | |
| 57 | ||
| 58 | /* Set read/write bytes */ | |
| 59 | if (read) { | |
| 60 | outb(0xC,0x46); outb(0xB,0x46); | |
| 61 | } else { | |
| 62 | outb(0xC,0x4A); outb(0xB,0x4A); | |
| 63 | } | |
| 64 | /* Send start address */ | |
| 65 | if (raw) phys = (unsigned long) bounce; | |
| 66 | else phys = addr; | |
| 67 | /* translate to physical */ | |
| 68 | phys = phys - sbase; | |
| 69 | outb(0x4,phys & 0xFF); | |
| 70 | outb(0x4,(phys>>8) & 0xFF); | |
| 71 | outb(0x81,(phys>>16) & 0xFF); | |
| 72 | /* Send count */ | |
| 73 | nbytes--; | |
| 74 | outb(0x5,nbytes & 0xFF); | |
| 75 | outb(0x5,(nbytes>>8) & 0xFF); | |
| 76 | /* set channel 2 */ | |
| 77 | outb(0x0A,chan); | |
| 78 | } |