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Release 4.14 arch/sh/drivers/dma/dma-g2.c

/*
 * arch/sh/drivers/dma/dma-g2.c
 *
 * G2 bus DMA support
 *
 * Copyright (C) 2003 - 2006  Paul Mundt
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <asm/cacheflush.h>
#include <mach/sysasic.h>
#include <mach/dma.h>
#include <asm/dma.h>


struct g2_channel {
	
unsigned long g2_addr;		/* G2 bus address */
	
unsigned long root_addr;	/* Root bus (SH-4) address */
	
unsigned long size;		/* Size (in bytes), 32-byte aligned */
	
unsigned long direction;	/* Transfer direction */
	
unsigned long ctrl;		/* Transfer control */
	
unsigned long chan_enable;	/* Channel enable */
	
unsigned long xfer_enable;	/* Transfer enable */
	
unsigned long xfer_stat;	/* Transfer status */
} __attribute__ ((aligned(32)));


struct g2_status {
	
unsigned long g2_addr;
	
unsigned long root_addr;
	
unsigned long size;
	
unsigned long status;
} __attribute__ ((aligned(16)));


struct g2_dma_info {
	
struct g2_channel channel[G2_NR_DMA_CHANNELS];
	
unsigned long pad1[G2_NR_DMA_CHANNELS];
	
unsigned long wait_state;
	
unsigned long pad2[10];
	
unsigned long magic;
	
struct g2_status status[G2_NR_DMA_CHANNELS];
} __attribute__ ((aligned(256)));


static volatile struct g2_dma_info *g2_dma = (volatile struct g2_dma_info *)0xa05f7800;


#define g2_bytes_remaining(i) \
	((g2_dma->channel[i].size - \
          g2_dma->status[i].size) & 0x0fffffff)


static irqreturn_t g2_dma_interrupt(int irq, void *dev_id) { int i; for (i = 0; i < G2_NR_DMA_CHANNELS; i++) { if (g2_dma->status[i].status & 0x20000000) { unsigned int bytes = g2_bytes_remaining(i); if (likely(bytes == 0)) { struct dma_info *info = dev_id; struct dma_channel *chan = info->channels + i; wake_up(&chan->wait_queue); return IRQ_HANDLED; } } } return IRQ_NONE; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt8283.67%150.00%
Andrew Morton1616.33%150.00%
Total98100.00%2100.00%


static int g2_enable_dma(struct dma_channel *chan) { unsigned int chan_nr = chan->chan; g2_dma->channel[chan_nr].chan_enable = 1; g2_dma->channel[chan_nr].xfer_enable = 1; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton3886.36%150.00%
Paul Mundt613.64%150.00%
Total44100.00%2100.00%


static int g2_disable_dma(struct dma_channel *chan) { unsigned int chan_nr = chan->chan; g2_dma->channel[chan_nr].chan_enable = 0; g2_dma->channel[chan_nr].xfer_enable = 0; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton3886.36%150.00%
Paul Mundt613.64%150.00%
Total44100.00%2100.00%


static int g2_xfer_dma(struct dma_channel *chan) { unsigned int chan_nr = chan->chan; if (chan->sar & 31) { printk("g2dma: unaligned source 0x%lx\n", chan->sar); return -EINVAL; } if (chan->dar & 31) { printk("g2dma: unaligned dest 0x%lx\n", chan->dar); return -EINVAL; } /* Align the count */ if (chan->count & 31) chan->count = (chan->count + (32 - 1)) & ~(32 - 1); /* Fixup destination */ chan->dar += 0xa0800000; /* Fixup direction */ chan->mode = !chan->mode; flush_icache_range((unsigned long)chan->sar, chan->count); g2_disable_dma(chan); g2_dma->channel[chan_nr].g2_addr = chan->dar & 0x1fffffe0; g2_dma->channel[chan_nr].root_addr = chan->sar & 0x1fffffe0; g2_dma->channel[chan_nr].size = (chan->count & ~31) | 0x80000000; g2_dma->channel[chan_nr].direction = chan->mode; /* * bit 0 - ??? * bit 1 - if set, generate a hardware event on transfer completion * bit 2 - ??? something to do with suspend? */ g2_dma->channel[chan_nr].ctrl = 5; /* ?? */ g2_enable_dma(chan); /* debug cruft */ pr_debug("count, sar, dar, mode, ctrl, chan, xfer: %ld, 0x%08lx, " "0x%08lx, %ld, %ld, %ld, %ld\n", g2_dma->channel[chan_nr].size, g2_dma->channel[chan_nr].root_addr, g2_dma->channel[chan_nr].g2_addr, g2_dma->channel[chan_nr].direction, g2_dma->channel[chan_nr].ctrl, g2_dma->channel[chan_nr].chan_enable, g2_dma->channel[chan_nr].xfer_enable); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton25488.19%150.00%
Paul Mundt3411.81%150.00%
Total288100.00%2100.00%


static int g2_get_residue(struct dma_channel *chan) { return g2_bytes_remaining(chan->chan); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt19100.00%1100.00%
Total19100.00%1100.00%

static struct dma_ops g2_dma_ops = { .xfer = g2_xfer_dma, .get_residue = g2_get_residue, }; static struct dma_info g2_dma_info = { .name = "g2_dmac", .nr_channels = 4, .ops = &g2_dma_ops, .flags = DMAC_CHANNELS_TEI_CAPABLE, };
static int __init g2_dma_init(void) { int ret; ret = request_irq(HW_EVENT_G2_DMA, g2_dma_interrupt, 0, "g2 DMA handler", &g2_dma_info); if (unlikely(ret)) return -EINVAL; /* Magic */ g2_dma->wait_state = 27; g2_dma->magic = 0x4659404f; ret = register_dmac(&g2_dma_info); if (unlikely(ret != 0)) free_irq(HW_EVENT_G2_DMA, &g2_dma_info); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt4455.00%240.00%
Andrew Morton3341.25%120.00%
Julia Lawall22.50%120.00%
Yong Zhang11.25%120.00%
Total80100.00%5100.00%


static void __exit g2_dma_exit(void) { free_irq(HW_EVENT_G2_DMA, &g2_dma_info); unregister_dmac(&g2_dma_info); }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton1565.22%133.33%
Paul Mundt626.09%133.33%
Julia Lawall28.70%133.33%
Total23100.00%3100.00%

subsys_initcall(g2_dma_init); module_exit(g2_dma_exit); MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>"); MODULE_DESCRIPTION("G2 bus DMA driver"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton60170.87%114.29%
Paul Mundt24228.54%457.14%
Julia Lawall40.47%114.29%
Yong Zhang10.12%114.29%
Total848100.00%7100.00%
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