339 lines
7.3 KiB
C
339 lines
7.3 KiB
C
/*
|
|
* linux/arch/arm/mach-rpc/dma.c
|
|
*
|
|
* Copyright (C) 1998 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.
|
|
*
|
|
* DMA functions specific to RiscPC architecture
|
|
*/
|
|
#include <linux/slab.h>
|
|
#include <linux/mman.h>
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/pci.h>
|
|
|
|
#include <asm/page.h>
|
|
#include <asm/dma.h>
|
|
#include <asm/fiq.h>
|
|
#include <asm/io.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/hardware.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#include <asm/mach/dma.h>
|
|
#include <asm/hardware/iomd.h>
|
|
|
|
#if 0
|
|
typedef enum {
|
|
dma_size_8 = 1,
|
|
dma_size_16 = 2,
|
|
dma_size_32 = 4,
|
|
dma_size_128 = 16
|
|
} dma_size_t;
|
|
#endif
|
|
|
|
#define TRANSFER_SIZE 2
|
|
|
|
#define CURA (0)
|
|
#define ENDA (IOMD_IO0ENDA - IOMD_IO0CURA)
|
|
#define CURB (IOMD_IO0CURB - IOMD_IO0CURA)
|
|
#define ENDB (IOMD_IO0ENDB - IOMD_IO0CURA)
|
|
#define CR (IOMD_IO0CR - IOMD_IO0CURA)
|
|
#define ST (IOMD_IO0ST - IOMD_IO0CURA)
|
|
|
|
static void iomd_get_next_sg(struct scatterlist *sg, dma_t *dma)
|
|
{
|
|
unsigned long end, offset, flags = 0;
|
|
|
|
if (dma->sg) {
|
|
sg->dma_address = dma->sg->dma_address;
|
|
offset = sg->dma_address & ~PAGE_MASK;
|
|
|
|
end = offset + dma->sg->length;
|
|
|
|
if (end > PAGE_SIZE)
|
|
end = PAGE_SIZE;
|
|
|
|
if (offset + TRANSFER_SIZE >= end)
|
|
flags |= DMA_END_L;
|
|
|
|
sg->length = end - TRANSFER_SIZE;
|
|
|
|
dma->sg->length -= end - offset;
|
|
dma->sg->dma_address += end - offset;
|
|
|
|
if (dma->sg->length == 0) {
|
|
if (dma->sgcount > 1) {
|
|
dma->sg++;
|
|
dma->sgcount--;
|
|
} else {
|
|
dma->sg = NULL;
|
|
flags |= DMA_END_S;
|
|
}
|
|
}
|
|
} else {
|
|
flags = DMA_END_S | DMA_END_L;
|
|
sg->dma_address = 0;
|
|
sg->length = 0;
|
|
}
|
|
|
|
sg->length |= flags;
|
|
}
|
|
|
|
static irqreturn_t iomd_dma_handle(int irq, void *dev_id, struct pt_regs *regs)
|
|
{
|
|
dma_t *dma = (dma_t *)dev_id;
|
|
unsigned long base = dma->dma_base;
|
|
|
|
do {
|
|
unsigned int status;
|
|
|
|
status = iomd_readb(base + ST);
|
|
if (!(status & DMA_ST_INT))
|
|
return IRQ_HANDLED;
|
|
|
|
if ((dma->state ^ status) & DMA_ST_AB)
|
|
iomd_get_next_sg(&dma->cur_sg, dma);
|
|
|
|
switch (status & (DMA_ST_OFL | DMA_ST_AB)) {
|
|
case DMA_ST_OFL: /* OIA */
|
|
case DMA_ST_AB: /* .IB */
|
|
iomd_writel(dma->cur_sg.dma_address, base + CURA);
|
|
iomd_writel(dma->cur_sg.length, base + ENDA);
|
|
dma->state = DMA_ST_AB;
|
|
break;
|
|
|
|
case DMA_ST_OFL | DMA_ST_AB: /* OIB */
|
|
case 0: /* .IA */
|
|
iomd_writel(dma->cur_sg.dma_address, base + CURB);
|
|
iomd_writel(dma->cur_sg.length, base + ENDB);
|
|
dma->state = 0;
|
|
break;
|
|
}
|
|
|
|
if (status & DMA_ST_OFL &&
|
|
dma->cur_sg.length == (DMA_END_S|DMA_END_L))
|
|
break;
|
|
} while (1);
|
|
|
|
dma->state = ~DMA_ST_AB;
|
|
disable_irq(irq);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int iomd_request_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
return request_irq(dma->dma_irq, iomd_dma_handle,
|
|
SA_INTERRUPT, dma->device_id, dma);
|
|
}
|
|
|
|
static void iomd_free_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
free_irq(dma->dma_irq, dma);
|
|
}
|
|
|
|
static void iomd_enable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
unsigned long dma_base = dma->dma_base;
|
|
unsigned int ctrl = TRANSFER_SIZE | DMA_CR_E;
|
|
|
|
if (dma->invalid) {
|
|
dma->invalid = 0;
|
|
|
|
/*
|
|
* Cope with ISA-style drivers which expect cache
|
|
* coherence.
|
|
*/
|
|
if (!dma->using_sg) {
|
|
dma->buf.dma_address = pci_map_single(NULL,
|
|
dma->buf.__address, dma->buf.length,
|
|
dma->dma_mode == DMA_MODE_READ ?
|
|
PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE);
|
|
}
|
|
|
|
iomd_writeb(DMA_CR_C, dma_base + CR);
|
|
dma->state = DMA_ST_AB;
|
|
}
|
|
|
|
if (dma->dma_mode == DMA_MODE_READ)
|
|
ctrl |= DMA_CR_D;
|
|
|
|
iomd_writeb(ctrl, dma_base + CR);
|
|
enable_irq(dma->dma_irq);
|
|
}
|
|
|
|
static void iomd_disable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
unsigned long dma_base = dma->dma_base;
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
if (dma->state != ~DMA_ST_AB)
|
|
disable_irq(dma->dma_irq);
|
|
iomd_writeb(0, dma_base + CR);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
static int iomd_set_dma_speed(dmach_t channel, dma_t *dma, int cycle)
|
|
{
|
|
int tcr, speed;
|
|
|
|
if (cycle < 188)
|
|
speed = 3;
|
|
else if (cycle <= 250)
|
|
speed = 2;
|
|
else if (cycle < 438)
|
|
speed = 1;
|
|
else
|
|
speed = 0;
|
|
|
|
tcr = iomd_readb(IOMD_DMATCR);
|
|
speed &= 3;
|
|
|
|
switch (channel) {
|
|
case DMA_0:
|
|
tcr = (tcr & ~0x03) | speed;
|
|
break;
|
|
|
|
case DMA_1:
|
|
tcr = (tcr & ~0x0c) | (speed << 2);
|
|
break;
|
|
|
|
case DMA_2:
|
|
tcr = (tcr & ~0x30) | (speed << 4);
|
|
break;
|
|
|
|
case DMA_3:
|
|
tcr = (tcr & ~0xc0) | (speed << 6);
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
iomd_writeb(tcr, IOMD_DMATCR);
|
|
|
|
return speed;
|
|
}
|
|
|
|
static struct dma_ops iomd_dma_ops = {
|
|
.type = "IOMD",
|
|
.request = iomd_request_dma,
|
|
.free = iomd_free_dma,
|
|
.enable = iomd_enable_dma,
|
|
.disable = iomd_disable_dma,
|
|
.setspeed = iomd_set_dma_speed,
|
|
};
|
|
|
|
static struct fiq_handler fh = {
|
|
.name = "floppydma"
|
|
};
|
|
|
|
static void floppy_enable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
void *fiqhandler_start;
|
|
unsigned int fiqhandler_length;
|
|
struct pt_regs regs;
|
|
|
|
if (dma->using_sg)
|
|
BUG();
|
|
|
|
if (dma->dma_mode == DMA_MODE_READ) {
|
|
extern unsigned char floppy_fiqin_start, floppy_fiqin_end;
|
|
fiqhandler_start = &floppy_fiqin_start;
|
|
fiqhandler_length = &floppy_fiqin_end - &floppy_fiqin_start;
|
|
} else {
|
|
extern unsigned char floppy_fiqout_start, floppy_fiqout_end;
|
|
fiqhandler_start = &floppy_fiqout_start;
|
|
fiqhandler_length = &floppy_fiqout_end - &floppy_fiqout_start;
|
|
}
|
|
|
|
regs.ARM_r9 = dma->buf.length;
|
|
regs.ARM_r10 = (unsigned long)dma->buf.__address;
|
|
regs.ARM_fp = (unsigned long)FLOPPYDMA_BASE;
|
|
|
|
if (claim_fiq(&fh)) {
|
|
printk("floppydma: couldn't claim FIQ.\n");
|
|
return;
|
|
}
|
|
|
|
set_fiq_handler(fiqhandler_start, fiqhandler_length);
|
|
set_fiq_regs(®s);
|
|
enable_fiq(dma->dma_irq);
|
|
}
|
|
|
|
static void floppy_disable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
disable_fiq(dma->dma_irq);
|
|
release_fiq(&fh);
|
|
}
|
|
|
|
static int floppy_get_residue(dmach_t channel, dma_t *dma)
|
|
{
|
|
struct pt_regs regs;
|
|
get_fiq_regs(®s);
|
|
return regs.ARM_r9;
|
|
}
|
|
|
|
static struct dma_ops floppy_dma_ops = {
|
|
.type = "FIQDMA",
|
|
.enable = floppy_enable_dma,
|
|
.disable = floppy_disable_dma,
|
|
.residue = floppy_get_residue,
|
|
};
|
|
|
|
/*
|
|
* This is virtual DMA - we don't need anything here.
|
|
*/
|
|
static void sound_enable_disable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
}
|
|
|
|
static struct dma_ops sound_dma_ops = {
|
|
.type = "VIRTUAL",
|
|
.enable = sound_enable_disable_dma,
|
|
.disable = sound_enable_disable_dma,
|
|
};
|
|
|
|
void __init arch_dma_init(dma_t *dma)
|
|
{
|
|
iomd_writeb(0, IOMD_IO0CR);
|
|
iomd_writeb(0, IOMD_IO1CR);
|
|
iomd_writeb(0, IOMD_IO2CR);
|
|
iomd_writeb(0, IOMD_IO3CR);
|
|
|
|
iomd_writeb(0xa0, IOMD_DMATCR);
|
|
|
|
dma[DMA_0].dma_base = IOMD_IO0CURA;
|
|
dma[DMA_0].dma_irq = IRQ_DMA0;
|
|
dma[DMA_0].d_ops = &iomd_dma_ops;
|
|
dma[DMA_1].dma_base = IOMD_IO1CURA;
|
|
dma[DMA_1].dma_irq = IRQ_DMA1;
|
|
dma[DMA_1].d_ops = &iomd_dma_ops;
|
|
dma[DMA_2].dma_base = IOMD_IO2CURA;
|
|
dma[DMA_2].dma_irq = IRQ_DMA2;
|
|
dma[DMA_2].d_ops = &iomd_dma_ops;
|
|
dma[DMA_3].dma_base = IOMD_IO3CURA;
|
|
dma[DMA_3].dma_irq = IRQ_DMA3;
|
|
dma[DMA_3].d_ops = &iomd_dma_ops;
|
|
dma[DMA_S0].dma_base = IOMD_SD0CURA;
|
|
dma[DMA_S0].dma_irq = IRQ_DMAS0;
|
|
dma[DMA_S0].d_ops = &iomd_dma_ops;
|
|
dma[DMA_S1].dma_base = IOMD_SD1CURA;
|
|
dma[DMA_S1].dma_irq = IRQ_DMAS1;
|
|
dma[DMA_S1].d_ops = &iomd_dma_ops;
|
|
dma[DMA_VIRTUAL_FLOPPY].dma_irq = FIQ_FLOPPYDATA;
|
|
dma[DMA_VIRTUAL_FLOPPY].d_ops = &floppy_dma_ops;
|
|
dma[DMA_VIRTUAL_SOUND].d_ops = &sound_dma_ops;
|
|
|
|
/*
|
|
* Setup DMA channels 2,3 to be for podules
|
|
* and channels 0,1 for internal devices
|
|
*/
|
|
iomd_writeb(DMA_EXT_IO3|DMA_EXT_IO2, IOMD_DMAEXT);
|
|
}
|