mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
102 lines
2.2 KiB
102 lines
2.2 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* arch/sh/drivers/dma/dma-pvr2.c |
|
* |
|
* NEC PowerVR 2 (Dreamcast) DMA support |
|
* |
|
* Copyright (C) 2003, 2004 Paul Mundt |
|
*/ |
|
#include <linux/init.h> |
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/interrupt.h> |
|
#include <mach/sysasic.h> |
|
#include <mach/dma.h> |
|
#include <asm/dma.h> |
|
#include <asm/io.h> |
|
|
|
static unsigned int xfer_complete; |
|
static int count; |
|
|
|
static irqreturn_t pvr2_dma_interrupt(int irq, void *dev_id) |
|
{ |
|
if (get_dma_residue(PVR2_CASCADE_CHAN)) { |
|
printk(KERN_WARNING "DMA: SH DMAC did not complete transfer " |
|
"on channel %d, waiting..\n", PVR2_CASCADE_CHAN); |
|
dma_wait_for_completion(PVR2_CASCADE_CHAN); |
|
} |
|
|
|
if (count++ < 10) |
|
pr_debug("Got a pvr2 dma interrupt for channel %d\n", |
|
irq - HW_EVENT_PVR2_DMA); |
|
|
|
xfer_complete = 1; |
|
|
|
return IRQ_HANDLED; |
|
} |
|
|
|
static int pvr2_request_dma(struct dma_channel *chan) |
|
{ |
|
if (__raw_readl(PVR2_DMA_MODE) != 0) |
|
return -EBUSY; |
|
|
|
__raw_writel(0, PVR2_DMA_LMMODE0); |
|
|
|
return 0; |
|
} |
|
|
|
static int pvr2_get_dma_residue(struct dma_channel *chan) |
|
{ |
|
return xfer_complete == 0; |
|
} |
|
|
|
static int pvr2_xfer_dma(struct dma_channel *chan) |
|
{ |
|
if (chan->sar || !chan->dar) |
|
return -EINVAL; |
|
|
|
xfer_complete = 0; |
|
|
|
__raw_writel(chan->dar, PVR2_DMA_ADDR); |
|
__raw_writel(chan->count, PVR2_DMA_COUNT); |
|
__raw_writel(chan->mode & DMA_MODE_MASK, PVR2_DMA_MODE); |
|
|
|
return 0; |
|
} |
|
|
|
static struct dma_ops pvr2_dma_ops = { |
|
.request = pvr2_request_dma, |
|
.get_residue = pvr2_get_dma_residue, |
|
.xfer = pvr2_xfer_dma, |
|
}; |
|
|
|
static struct dma_info pvr2_dma_info = { |
|
.name = "pvr2_dmac", |
|
.nr_channels = 1, |
|
.ops = &pvr2_dma_ops, |
|
.flags = DMAC_CHANNELS_TEI_CAPABLE, |
|
}; |
|
|
|
static int __init pvr2_dma_init(void) |
|
{ |
|
if (request_irq(HW_EVENT_PVR2_DMA, pvr2_dma_interrupt, 0, |
|
"pvr2 DMA handler", NULL)) |
|
pr_err("Failed to register pvr2 DMA handler interrupt\n"); |
|
request_dma(PVR2_CASCADE_CHAN, "pvr2 cascade"); |
|
|
|
return register_dmac(&pvr2_dma_info); |
|
} |
|
|
|
static void __exit pvr2_dma_exit(void) |
|
{ |
|
free_dma(PVR2_CASCADE_CHAN); |
|
free_irq(HW_EVENT_PVR2_DMA, 0); |
|
unregister_dmac(&pvr2_dma_info); |
|
} |
|
|
|
subsys_initcall(pvr2_dma_init); |
|
module_exit(pvr2_dma_exit); |
|
|
|
MODULE_AUTHOR("Paul Mundt <[email protected]>"); |
|
MODULE_DESCRIPTION("NEC PowerVR 2 DMA driver"); |
|
MODULE_LICENSE("GPL v2");
|
|
|