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Release 4.11 arch/arm/kernel/dma-isa.c

Directory: arch/arm/kernel
/*
 *  linux/arch/arm/kernel/dma-isa.c
 *
 *  Copyright (C) 1999-2000 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  ISA DMA primitives
 *  Taken from various sources, including:
 *   linux/include/asm/dma.h: Defines for using and allocating dma channels.
 *     Written by Hennus Bergman, 1992.
 *     High DMA channel support & info by Hannu Savolainen and John Boyd,
 *     Nov. 1992.
 *   arch/arm/kernel/dma-ebsa285.c
 *   Copyright (C) 1998 Phil Blundell
 */
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>

#include <asm/dma.h>
#include <asm/mach/dma.h>


#define ISA_DMA_MASK		0

#define ISA_DMA_MODE		1

#define ISA_DMA_CLRFF		2

#define ISA_DMA_PGHI		3

#define ISA_DMA_PGLO		4

#define ISA_DMA_ADDR		5

#define ISA_DMA_COUNT		6


static unsigned int isa_dma_port[8][7] = {
	/* MASK   MODE   CLRFF  PAGE_HI PAGE_LO ADDR COUNT */
	{  0x0a,  0x0b,  0x0c,  0x487,  0x087,  0x00, 0x01 },
	{  0x0a,  0x0b,  0x0c,  0x483,  0x083,  0x02, 0x03 },
	{  0x0a,  0x0b,  0x0c,  0x481,  0x081,  0x04, 0x05 },
	{  0x0a,  0x0b,  0x0c,  0x482,  0x082,  0x06, 0x07 },
	{  0xd4,  0xd6,  0xd8,  0x000,  0x000,  0xc0, 0xc2 },
	{  0xd4,  0xd6,  0xd8,  0x48b,  0x08b,  0xc4, 0xc6 },
	{  0xd4,  0xd6,  0xd8,  0x489,  0x089,  0xc8, 0xca },
	{  0xd4,  0xd6,  0xd8,  0x48a,  0x08a,  0xcc, 0xce }
};


static int isa_get_dma_residue(unsigned int chan, dma_t *dma) { unsigned int io_port = isa_dma_port[chan][ISA_DMA_COUNT]; int count; count = 1 + inb(io_port); count |= inb(io_port) << 8; return chan < 4 ? count : (count << 1); }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)5591.67%375.00%
Russell King58.33%125.00%
Total60100.00%4100.00%


static void isa_enable_dma(unsigned int chan, dma_t *dma) { if (dma->invalid) { unsigned long address, length; unsigned int mode; enum dma_data_direction direction; mode = (chan & 3) | dma->dma_mode; switch (dma->dma_mode & DMA_MODE_MASK) { case DMA_MODE_READ: direction = DMA_FROM_DEVICE; break; case DMA_MODE_WRITE: direction = DMA_TO_DEVICE; break; case DMA_MODE_CASCADE: direction = DMA_BIDIRECTIONAL; break; default: direction = DMA_NONE; break; } if (!dma->sg) { /* * Cope with ISA-style drivers which expect cache * coherence. */ dma->sg = &dma->buf; dma->sgcount = 1; dma->buf.length = dma->count; dma->buf.dma_address = dma_map_single(NULL, dma->addr, dma->count, direction); } address = dma->buf.dma_address; length = dma->buf.length - 1; outb(address >> 16, isa_dma_port[chan][ISA_DMA_PGLO]); outb(address >> 24, isa_dma_port[chan][ISA_DMA_PGHI]); if (chan >= 4) { address >>= 1; length >>= 1; } outb(0, isa_dma_port[chan][ISA_DMA_CLRFF]); outb(address, isa_dma_port[chan][ISA_DMA_ADDR]); outb(address >> 8, isa_dma_port[chan][ISA_DMA_ADDR]); outb(length, isa_dma_port[chan][ISA_DMA_COUNT]); outb(length >> 8, isa_dma_port[chan][ISA_DMA_COUNT]); outb(mode, isa_dma_port[chan][ISA_DMA_MODE]); dma->invalid = 0; } outb(chan & 3, isa_dma_port[chan][ISA_DMA_MASK]); }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)25180.71%450.00%
Russell King6019.29%450.00%
Total311100.00%8100.00%


static void isa_disable_dma(unsigned int chan, dma_t *dma) { outb(chan | 4, isa_dma_port[chan][ISA_DMA_MASK]); }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)2482.76%266.67%
Russell King517.24%133.33%
Total29100.00%3100.00%

static struct dma_ops isa_dma_ops = { .type = "ISA", .enable = isa_enable_dma, .disable = isa_disable_dma, .residue = isa_get_dma_residue, }; static struct resource dma_resources[] = { { .name = "dma1", .start = 0x0000, .end = 0x000f }, { .name = "dma low page", .start = 0x0080, .end = 0x008f }, { .name = "dma2", .start = 0x00c0, .end = 0x00df }, { .name = "dma high page", .start = 0x0480, .end = 0x048f } }; static dma_t isa_dma[8]; /* * ISA DMA always starts at channel 0 */
void __init isa_init_dma(void) { /* * Try to autodetect presence of an ISA DMA controller. * We do some minimal initialisation, and check that * channel 0's DMA address registers are writeable. */ outb(0xff, 0x0d); outb(0xff, 0xda); /* * Write high and low address, and then read them back * in the same order. */ outb(0x55, 0x00); outb(0xaa, 0x00); if (inb(0) == 0x55 && inb(0) == 0xaa) { unsigned int chan, i; for (chan = 0; chan < 8; chan++) { isa_dma[chan].d_ops = &isa_dma_ops; isa_disable_dma(chan, NULL); } outb(0x40, 0x0b); outb(0x41, 0x0b); outb(0x42, 0x0b); outb(0x43, 0x0b); outb(0xc0, 0xd6); outb(0x41, 0xd6); outb(0x42, 0xd6); outb(0x43, 0xd6); outb(0, 0xd4); outb(0x10, 0x08); outb(0x10, 0xd0); /* * Is this correct? According to my documentation, it * doesn't appear to be. It should be: * outb(0x3f, 0x40b); outb(0x3f, 0x4d6); */ outb(0x30, 0x40b); outb(0x31, 0x40b); outb(0x32, 0x40b); outb(0x33, 0x40b); outb(0x31, 0x4d6); outb(0x32, 0x4d6); outb(0x33, 0x4d6); for (i = 0; i < ARRAY_SIZE(dma_resources); i++) request_resource(&ioport_resource, dma_resources + i); for (chan = 0; chan < 8; chan++) { int ret = isa_dma_add(chan, &isa_dma[chan]); if (ret) pr_err("ISADMA%u: unable to register: %d\n", chan, ret); } request_dma(DMA_ISA_CASCADE, "cascade"); } }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)23178.04%440.00%
Russell King5819.59%440.00%
Linus Torvalds62.03%110.00%
Alejandro Martinez Ruiz10.34%110.00%
Total296100.00%10100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)80680.92%736.84%
Russell King14714.76%947.37%
Adrian Bunk363.61%15.26%
Linus Torvalds60.60%15.26%
Alejandro Martinez Ruiz10.10%15.26%
Total996100.00%19100.00%
Directory: arch/arm/kernel
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