From: Russell King Date: Mon, 8 Dec 2008 16:33:30 +0000 (+0000) Subject: [ARM] dma: rejig DMA initialization X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=2f757f2ab7411cf0e2779012d8cda0cbf2f80d26;p=linux-2.6-omap-h63xx.git [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: Russell King --- diff --git a/arch/arm/include/asm/mach/dma.h b/arch/arm/include/asm/mach/dma.h index 281ae7e40a9..38a3693f125 100644 --- a/arch/arm/include/asm/mach/dma.h +++ b/arch/arm/include/asm/mach/dma.h @@ -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); diff --git a/arch/arm/kernel/dma-isa.c b/arch/arm/kernel/dma-isa.c index 29eca48925d..da02a7ff341 100644 --- a/arch/arm/kernel/dma-isa.c +++ b/arch/arm/kernel/dma-isa.c @@ -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); + } } } diff --git a/arch/arm/kernel/dma.c b/arch/arm/kernel/dma.c index 0ffea3fc22d..aab24f03ea1 100644 --- a/arch/arm/kernel/dma.c +++ b/arch/arm/kernel/dma.c @@ -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); diff --git a/arch/arm/mach-footbridge/dma.c b/arch/arm/mach-footbridge/dma.c index e7b8a6adaf7..fdd94b182d7 100644 --- a/arch/arm/mach-footbridge/dma.c +++ b/arch/arm/mach-footbridge/dma.c @@ -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); diff --git a/arch/arm/mach-rpc/dma.c b/arch/arm/mach-rpc/dma.c index a86d3ed859a..efcf6718d1d 100644 --- a/arch/arm/mach-rpc/dma.c +++ b/arch/arm/mach-rpc/dma.c @@ -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); diff --git a/arch/arm/mach-shark/dma.c b/arch/arm/mach-shark/dma.c index 6774b8d5d13..10b5b8b3272 100644 --- a/arch/arm/mach-shark/dma.c +++ b/arch/arm/mach-shark/dma.c @@ -13,9 +13,11 @@ #include #include -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);