Commit 2f757f2a authored by Russell King's avatar Russell King Committed by Russell King
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[ARM] dma: rejig DMA initialization



Rather than having the central DMA multiplexer call the architecture
specific DMA initialization function, have each architecture DMA
initialization function use core_initcall(), and register each DMA
channel separately with the multiplexer.

This removes the array of dma structures in the central multiplexer,
replacing it with an array of pointers instead; this is more flexible
since it allows the drivers to wrap the DMA structure (eventually
allowing us to transition non-ISA DMA drivers away.)
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 3afb6e9c
......@@ -48,10 +48,12 @@ struct dma_struct {
struct dma_ops *d_ops;
};
/* Prototype: void arch_dma_init(dma)
* Purpose : Initialise architecture specific DMA
* Params : dma - pointer to array of DMA structures
/*
* isa_dma_add - add an ISA-style DMA channel
*/
extern void arch_dma_init(dma_t *dma);
extern int isa_dma_add(unsigned int, dma_t *dma);
extern void isa_init_dma(dma_t *dma);
/*
* Add the ISA DMA controller. Always takes channels 0-7.
*/
extern void isa_init_dma(void);
......@@ -160,7 +160,12 @@ static struct resource dma_resources[] = { {
.end = 0x048f
} };
void __init isa_init_dma(dma_t *dma)
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.
......@@ -178,10 +183,10 @@ void __init isa_init_dma(dma_t *dma)
outb(0xaa, 0x00);
if (inb(0) == 0x55 && inb(0) == 0xaa) {
int chan, i;
unsigned int chan, i;
for (chan = 0; chan < 8; chan++) {
dma[chan].d_ops = &isa_dma_ops;
isa_dma[chan].d_ops = &isa_dma_ops;
isa_disable_dma(chan, NULL);
}
......@@ -217,5 +222,12 @@ void __init isa_init_dma(dma_t *dma)
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)
printk(KERN_ERR "ISADMA%u: unable to register: %d\n",
chan, ret);
}
}
}
......@@ -23,16 +23,24 @@
DEFINE_SPINLOCK(dma_spin_lock);
EXPORT_SYMBOL(dma_spin_lock);
static dma_t dma_chan[MAX_DMA_CHANNELS];
static dma_t *dma_chan[MAX_DMA_CHANNELS];
static inline dma_t *dma_channel(unsigned int chan)
{
dma_t *dma = dma_chan + chan;
if (chan >= MAX_DMA_CHANNELS || !dma->d_ops)
if (chan >= MAX_DMA_CHANNELS)
return NULL;
return dma;
return dma_chan[chan];
}
int __init isa_dma_add(unsigned int chan, dma_t *dma)
{
if (!dma->d_ops)
return -EINVAL;
if (dma_chan[chan])
return -EBUSY;
dma_chan[chan] = dma;
return 0;
}
/*
......@@ -252,10 +260,3 @@ int get_dma_residue(unsigned int chan)
return ret;
}
EXPORT_SYMBOL(get_dma_residue);
static int __init init_dma(void)
{
arch_dma_init(dma_chan);
return 0;
}
core_initcall(init_dma);
......@@ -41,7 +41,7 @@ static struct dma_ops fb_dma_ops = {
};
#endif
void __init arch_dma_init(dma_t *dma)
static int __init fb_dma_init(void)
{
#if 0
dma[_DC21285_DMA(0)].d_ops = &fb_dma_ops;
......@@ -49,6 +49,8 @@ void __init arch_dma_init(dma_t *dma)
#endif
#ifdef CONFIG_ISA_DMA
if (footbridge_cfn_mode())
isa_init_dma(dma + _ISA_DMA(0));
isa_init_dma();
#endif
return 0;
}
core_initcall(fb_dma_init);
......@@ -302,8 +302,22 @@ static struct dma_ops sound_dma_ops = {
.disable = sound_enable_disable_dma,
};
void __init arch_dma_init(dma_t *dma)
static dma_t iomd_dma[6];
static dma_t floppy_dma = {
.dma_irq = FIQ_FLOPPYDATA,
.d_ops = &floppy_dma_ops,
};
static dma_t sound_dma = {
.d_ops = &sound_dma_ops,
};
static int __init rpc_dma_init(void)
{
unsigned int i;
int ret;
iomd_writeb(0, IOMD_IO0CR);
iomd_writeb(0, IOMD_IO1CR);
iomd_writeb(0, IOMD_IO2CR);
......@@ -311,31 +325,39 @@ void __init arch_dma_init(dma_t *dma)
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);
iomd_dma[DMA_0].dma_base = IOMD_IO0CURA;
iomd_dma[DMA_0].dma_irq = IRQ_DMA0;
iomd_dma[DMA_1].dma_base = IOMD_IO1CURA;
iomd_dma[DMA_1].dma_irq = IRQ_DMA1;
iomd_dma[DMA_2].dma_base = IOMD_IO2CURA;
iomd_dma[DMA_2].dma_irq = IRQ_DMA2;
iomd_dma[DMA_3].dma_base = IOMD_IO3CURA;
iomd_dma[DMA_3].dma_irq = IRQ_DMA3;
iomd_dma[DMA_S0].dma_base = IOMD_SD0CURA;
iomd_dma[DMA_S0].dma_irq = IRQ_DMAS0;
iomd_dma[DMA_S1].dma_base = IOMD_SD1CURA;
iomd_dma[DMA_S1].dma_irq = IRQ_DMAS1;
for (i = DMA_0; i <= DMA_S1; i++) {
iomd_dma[i].d_ops = &iomd_dma_ops;
ret = isa_dma_add(i, &iomd_dma[i]);
if (ret)
printk("IOMDDMA%u: unable to register: %d\n", i, ret);
}
ret = isa_dma_add(DMA_VIRTUAL_FLOPPY, &floppy_dma);
if (ret)
printk("IOMDFLOPPY: unable to register: %d\n", ret);
ret = isa_dma_add(DMA_VIRTUAL_SOUND, &sound_dma);
if (ret)
printk("IOMDSOUND: unable to register: %d\n", ret);
return 0;
}
core_initcall(rpc_dma_init);
......@@ -13,9 +13,11 @@
#include <asm/dma.h>
#include <asm/mach/dma.h>
void __init arch_dma_init(dma_t *dma)
static int __init shark_dma_init(void)
{
#ifdef CONFIG_ISA_DMA
isa_init_dma(dma);
isa_init_dma();
#endif
return 0;
}
core_initcall(shark_dma_init);
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