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Viewing changes to arch/sh/drivers/dma/dma-pvr2.c

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-tz023xykf0i6eosh
Tags: upstream-3.2.0
Import upstream version 3.2.0

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arch/sh/drivers/dma/dma-pvr2.c
 
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/*
 
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 * arch/sh/drivers/dma/dma-pvr2.c
 
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 *
 
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 * NEC PowerVR 2 (Dreamcast) DMA support
 
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 *
 
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 * Copyright (C) 2003, 2004  Paul Mundt
 
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 *
 
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 * This file is subject to the terms and conditions of the GNU General Public
 
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 * License.  See the file "COPYING" in the main directory of this archive
 
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 * for more details.
 
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 */
 
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#include <linux/init.h>
 
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#include <linux/kernel.h>
 
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#include <linux/module.h>
 
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#include <linux/interrupt.h>
 
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#include <mach/sysasic.h>
 
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#include <mach/dma.h>
 
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#include <asm/dma.h>
 
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#include <asm/io.h>
 
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static unsigned int xfer_complete;
 
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static int count;
 
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static irqreturn_t pvr2_dma_interrupt(int irq, void *dev_id)
 
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{
 
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        if (get_dma_residue(PVR2_CASCADE_CHAN)) {
 
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                printk(KERN_WARNING "DMA: SH DMAC did not complete transfer "
 
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                       "on channel %d, waiting..\n", PVR2_CASCADE_CHAN);
 
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                dma_wait_for_completion(PVR2_CASCADE_CHAN);
 
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        }
 
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        if (count++ < 10)
 
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                pr_debug("Got a pvr2 dma interrupt for channel %d\n",
 
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                         irq - HW_EVENT_PVR2_DMA);
 
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        xfer_complete = 1;
 
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        return IRQ_HANDLED;
 
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}
 
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static int pvr2_request_dma(struct dma_channel *chan)
 
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{
 
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        if (__raw_readl(PVR2_DMA_MODE) != 0)
 
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                return -EBUSY;
 
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        __raw_writel(0, PVR2_DMA_LMMODE0);
 
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        return 0;
 
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}
 
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static int pvr2_get_dma_residue(struct dma_channel *chan)
 
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{
 
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        return xfer_complete == 0;
 
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}
 
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static int pvr2_xfer_dma(struct dma_channel *chan)
 
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{
 
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        if (chan->sar || !chan->dar)
 
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                return -EINVAL;
 
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        xfer_complete = 0;
 
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        __raw_writel(chan->dar, PVR2_DMA_ADDR);
 
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        __raw_writel(chan->count, PVR2_DMA_COUNT);
 
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        __raw_writel(chan->mode & DMA_MODE_MASK, PVR2_DMA_MODE);
 
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        return 0;
 
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}
 
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static struct irqaction pvr2_dma_irq = {
 
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        .name           = "pvr2 DMA handler",
 
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        .handler        = pvr2_dma_interrupt,
 
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};
 
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static struct dma_ops pvr2_dma_ops = {
 
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        .request        = pvr2_request_dma,
 
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        .get_residue    = pvr2_get_dma_residue,
 
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        .xfer           = pvr2_xfer_dma,
 
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};
 
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static struct dma_info pvr2_dma_info = {
 
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        .name           = "pvr2_dmac",
 
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        .nr_channels    = 1,
 
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        .ops            = &pvr2_dma_ops,
 
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        .flags          = DMAC_CHANNELS_TEI_CAPABLE,
 
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};
 
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static int __init pvr2_dma_init(void)
 
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{
 
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        setup_irq(HW_EVENT_PVR2_DMA, &pvr2_dma_irq);
 
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        request_dma(PVR2_CASCADE_CHAN, "pvr2 cascade");
 
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        return register_dmac(&pvr2_dma_info);
 
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}
 
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static void __exit pvr2_dma_exit(void)
 
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{
 
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        free_dma(PVR2_CASCADE_CHAN);
 
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        free_irq(HW_EVENT_PVR2_DMA, 0);
 
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        unregister_dmac(&pvr2_dma_info);
 
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}
 
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subsys_initcall(pvr2_dma_init);
 
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module_exit(pvr2_dma_exit);
 
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MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
 
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MODULE_DESCRIPTION("NEC PowerVR 2 DMA driver");
 
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MODULE_LICENSE("GPL");