Lines Matching +full:no +full:- +full:read +full:- +full:rollover
1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
77 /* high byte of address is stored in this port for i-th dma channel */
307 outb(waport + 1, --nbytes);
334 waport = DMA2_CHN(chan - 4);
341 outb(waport + 2, --nbytes);
370 /* copy bounce buffer on read */
382 * (non-contiguous physical pages, outside of bus address space,
392 u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1);
398 panic("isa_dmacheck: no physical page present");
422 * one rollover in the low count byte can be expected within the
425 * There are three gaps in which a rollover can occur :
427 * - read low1
429 * - read high1
431 * - read low2
433 * - read high2
435 * If a rollover occurs in gap1 or gap2, the low2 value will be
442 * or -1 if the channel requested is not active.
457 return(-1);
464 return -2 ;
471 waport = DMA2_CHN(chan - 4) + 2;
474 disable_intr(); /* no interrupts Mr Jones! */
485 * Note that after TC, the count will read 0xffff, while we want
540 return -2 ;
590 1, /* no softc */