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Release 4.14 arch/frv/kernel/dma.c

Directory: arch/frv/kernel
/* dma.c: DMA controller management on FR401 and the like
 *
 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <asm/dma.h>
#include <asm/gpio-regs.h>
#include <asm/irc-regs.h>
#include <asm/cpu-irqs.h>


struct frv_dma_channel {
	
uint8_t			flags;

#define FRV_DMA_FLAGS_RESERVED	0x01

#define FRV_DMA_FLAGS_INUSE	0x02

#define FRV_DMA_FLAGS_PAUSED	0x04
	
uint8_t			cap;		/* capabilities available */
	
int			irq;		/* completion IRQ */
	
uint32_t		dreqbit;
	
uint32_t		dackbit;
	
uint32_t		donebit;
	
const unsigned long	ioaddr;		/* DMA controller regs addr */
	
const char		*devname;
	
dma_irq_handler_t	handler;
	
void			*data;
};



#define __get_DMAC(IO,X)	({ *(volatile unsigned long *)((IO) + DMAC_##X##x); })


#define __set_DMAC(IO,X,V)					\
do {                                                            \
        *(volatile unsigned long *)((IO) + DMAC_##X##x) = (V);  \
        mb();                                                   \
} while(0)


#define ___set_DMAC(IO,X,V)					\
do {                                                            \
        *(volatile unsigned long *)((IO) + DMAC_##X##x) = (V);  \
} while(0)



static struct frv_dma_channel frv_dma_channels[FRV_DMA_NCHANS] = {
	[0] = {
		.cap		= FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK | FRV_DMA_CAP_DONE,
		.irq		= IRQ_CPU_DMA0,
		.dreqbit	= SIR_DREQ0_INPUT,
		.dackbit	= SOR_DACK0_OUTPUT,
		.donebit	= SOR_DONE0_OUTPUT,
		.ioaddr		= 0xfe000900,
        },
	[1] = {
		.cap		= FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK | FRV_DMA_CAP_DONE,
		.irq		= IRQ_CPU_DMA1,
		.dreqbit	= SIR_DREQ1_INPUT,
		.dackbit	= SOR_DACK1_OUTPUT,
		.donebit	= SOR_DONE1_OUTPUT,
		.ioaddr		= 0xfe000980,
        },
	[2] = {
		.cap		= FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK,
		.irq		= IRQ_CPU_DMA2,
		.dreqbit	= SIR_DREQ2_INPUT,
		.dackbit	= SOR_DACK2_OUTPUT,
		.ioaddr		= 0xfe000a00,
        },
	[3] = {
		.cap		= FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK,
		.irq		= IRQ_CPU_DMA3,
		.dreqbit	= SIR_DREQ3_INPUT,
		.dackbit	= SOR_DACK3_OUTPUT,
		.ioaddr		= 0xfe000a80,
        },
	[4] = {
		.cap		= FRV_DMA_CAP_DREQ,
		.irq		= IRQ_CPU_DMA4,
		.dreqbit	= SIR_DREQ4_INPUT,
		.ioaddr		= 0xfe001000,
        },
	[5] = {
		.cap		= FRV_DMA_CAP_DREQ,
		.irq		= IRQ_CPU_DMA5,
		.dreqbit	= SIR_DREQ5_INPUT,
		.ioaddr		= 0xfe001080,
        },
	[6] = {
		.cap		= FRV_DMA_CAP_DREQ,
		.irq		= IRQ_CPU_DMA6,
		.dreqbit	= SIR_DREQ6_INPUT,
		.ioaddr		= 0xfe001100,
        },
	[7] = {
		.cap		= FRV_DMA_CAP_DREQ,
		.irq		= IRQ_CPU_DMA7,
		.dreqbit	= SIR_DREQ7_INPUT,
		.ioaddr		= 0xfe001180,
        },
};

static DEFINE_RWLOCK(frv_dma_channels_lock);


unsigned int frv_dma_inprogress;


#define frv_clear_dma_inprogress(channel) \
	(void)__atomic32_fetch_and(~(1 << (channel)), &frv_dma_inprogress);


#define frv_set_dma_inprogress(channel) \
	(void)__atomic32_fetch_or(1 << (channel), &frv_dma_inprogress);

/*****************************************************************************/
/*
 * DMA irq handler - determine channel involved, grab status and call real handler
 */

static irqreturn_t dma_irq_handler(int irq, void *_channel) { struct frv_dma_channel *channel = _channel; frv_clear_dma_inprogress(channel - frv_dma_channels); return channel->handler(channel - frv_dma_channels, __get_DMAC(channel->ioaddr, CSTR), channel->data); }

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/* end dma_irq_handler() */ /*****************************************************************************/ /* * Determine which DMA controllers are present on this CPU */
void __init frv_dma_init(void) { unsigned long psr = __get_PSR(); int num_dma, i; /* First, determine how many DMA channels are available */ switch (PSR_IMPLE(psr)) { case PSR_IMPLE_FR405: case PSR_IMPLE_FR451: case PSR_IMPLE_FR501: case PSR_IMPLE_FR551: num_dma = FRV_DMA_8CHANS; break; case PSR_IMPLE_FR401: default: num_dma = FRV_DMA_4CHANS; break; } /* Now mark all of the non-existent channels as reserved */ for(i = num_dma; i < FRV_DMA_NCHANS; i++) frv_dma_channels[i].flags = FRV_DMA_FLAGS_RESERVED; }

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/* end frv_dma_init() */ /*****************************************************************************/ /* * allocate a DMA controller channel and the IRQ associated with it */
int frv_dma_open(const char *devname, unsigned long dmamask, int dmacap, dma_irq_handler_t handler, unsigned long irq_flags, void *data) { struct frv_dma_channel *channel; int dma, ret; uint32_t val; write_lock(&frv_dma_channels_lock); ret = -ENOSPC; for (dma = FRV_DMA_NCHANS - 1; dma >= 0; dma--) { channel = &frv_dma_channels[dma]; if (!test_bit(dma, &dmamask)) continue; if ((channel->cap & dmacap) != dmacap) continue; if (!frv_dma_channels[dma].flags) goto found; } goto out; found: ret = request_irq(channel->irq, dma_irq_handler, irq_flags, devname, channel); if (ret < 0) goto out; /* okay, we've allocated all the resources */ channel = &frv_dma_channels[dma]; channel->flags |= FRV_DMA_FLAGS_INUSE; channel->devname = devname; channel->handler = handler; channel->data = data; /* Now make sure we are set up for DMA and not GPIO */ /* SIR bit must be set for DMA to work */ __set_SIR(channel->dreqbit | __get_SIR()); /* SOR bits depend on what the caller requests */ val = __get_SOR(); if(dmacap & FRV_DMA_CAP_DACK) val |= channel->dackbit; else val &= ~channel->dackbit; if(dmacap & FRV_DMA_CAP_DONE) val |= channel->donebit; else val &= ~channel->donebit; __set_SOR(val); ret = dma; out: write_unlock(&frv_dma_channels_lock); return ret; }

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/* end frv_dma_open() */ EXPORT_SYMBOL(frv_dma_open); /*****************************************************************************/ /* * close a DMA channel and its associated interrupt */
void frv_dma_close(int dma) { struct frv_dma_channel *channel = &frv_dma_channels[dma]; unsigned long flags; write_lock_irqsave(&frv_dma_channels_lock, flags); free_irq(channel->irq, channel); frv_dma_stop(dma); channel->flags &= ~FRV_DMA_FLAGS_INUSE; write_unlock_irqrestore(&frv_dma_channels_lock, flags); }

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/* end frv_dma_close() */ EXPORT_SYMBOL(frv_dma_close); /*****************************************************************************/ /* * set static configuration on a DMA channel */
void frv_dma_config(int dma, unsigned long ccfr, unsigned long cctr, unsigned long apr) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; ___set_DMAC(ioaddr, CCFR, ccfr); ___set_DMAC(ioaddr, CCTR, cctr); ___set_DMAC(ioaddr, APR, apr); mb(); }

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/* end frv_dma_config() */ EXPORT_SYMBOL(frv_dma_config); /*****************************************************************************/ /* * start a DMA channel */
void frv_dma_start(int dma, unsigned long sba, unsigned long dba, unsigned long pix, unsigned long six, unsigned long bcl) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; ___set_DMAC(ioaddr, SBA, sba); ___set_DMAC(ioaddr, DBA, dba); ___set_DMAC(ioaddr, PIX, pix); ___set_DMAC(ioaddr, SIX, six); ___set_DMAC(ioaddr, BCL, bcl); ___set_DMAC(ioaddr, CSTR, 0); mb(); __set_DMAC(ioaddr, CCTR, __get_DMAC(ioaddr, CCTR) | DMAC_CCTRx_ACT); frv_set_dma_inprogress(dma); }

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/* end frv_dma_start() */ EXPORT_SYMBOL(frv_dma_start); /*****************************************************************************/ /* * restart a DMA channel that's been stopped in circular addressing mode by comparison-end */
void frv_dma_restart_circular(int dma, unsigned long six) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; ___set_DMAC(ioaddr, SIX, six); ___set_DMAC(ioaddr, CSTR, __get_DMAC(ioaddr, CSTR) & ~DMAC_CSTRx_CE); mb(); __set_DMAC(ioaddr, CCTR, __get_DMAC(ioaddr, CCTR) | DMAC_CCTRx_ACT); frv_set_dma_inprogress(dma); }

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/* end frv_dma_restart_circular() */ EXPORT_SYMBOL(frv_dma_restart_circular); /*****************************************************************************/ /* * stop a DMA channel */
void frv_dma_stop(int dma) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; uint32_t cctr; ___set_DMAC(ioaddr, CSTR, 0); cctr = __get_DMAC(ioaddr, CCTR); cctr &= ~(DMAC_CCTRx_IE | DMAC_CCTRx_ACT); cctr |= DMAC_CCTRx_FC; /* fifo clear */ __set_DMAC(ioaddr, CCTR, cctr); __set_DMAC(ioaddr, BCL, 0); frv_clear_dma_inprogress(dma); }

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/* end frv_dma_stop() */ EXPORT_SYMBOL(frv_dma_stop); /*****************************************************************************/ /* * test interrupt status of DMA channel */
int is_frv_dma_interrupting(int dma) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; return __get_DMAC(ioaddr, CSTR) & (1 << 23); }

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/* end is_frv_dma_interrupting() */ EXPORT_SYMBOL(is_frv_dma_interrupting); /*****************************************************************************/ /* * dump data about a DMA channel */
void frv_dma_dump(int dma) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; unsigned long cstr, pix, six, bcl; cstr = __get_DMAC(ioaddr, CSTR); pix = __get_DMAC(ioaddr, PIX); six = __get_DMAC(ioaddr, SIX); bcl = __get_DMAC(ioaddr, BCL); printk("DMA[%d] cstr=%lx pix=%lx six=%lx bcl=%lx\n", dma, cstr, pix, six, bcl); }

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/* end frv_dma_dump() */ EXPORT_SYMBOL(frv_dma_dump); /*****************************************************************************/ /* * pause all DMA controllers * - called by clock mangling routines * - caller must be holding interrupts disabled */
void frv_dma_pause_all(void) { struct frv_dma_channel *channel; unsigned long ioaddr; unsigned long cstr, cctr; int dma; write_lock(&frv_dma_channels_lock); for (dma = FRV_DMA_NCHANS - 1; dma >= 0; dma--) { channel = &frv_dma_channels[dma]; if (!(channel->flags & FRV_DMA_FLAGS_INUSE)) continue; ioaddr = channel->ioaddr; cctr = __get_DMAC(ioaddr, CCTR); if (cctr & DMAC_CCTRx_ACT) { cctr &= ~DMAC_CCTRx_ACT; __set_DMAC(ioaddr, CCTR, cctr); do { cstr = __get_DMAC(ioaddr, CSTR); } while (cstr & DMAC_CSTRx_BUSY); if (cstr & DMAC_CSTRx_FED) channel->flags |= FRV_DMA_FLAGS_PAUSED; frv_clear_dma_inprogress(dma); } } }

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/* end frv_dma_pause_all() */ EXPORT_SYMBOL(frv_dma_pause_all); /*****************************************************************************/ /* * resume paused DMA controllers * - called by clock mangling routines * - caller must be holding interrupts disabled */
void frv_dma_resume_all(void) { struct frv_dma_channel *channel; unsigned long ioaddr; unsigned long cstr, cctr; int dma; for (dma = FRV_DMA_NCHANS - 1; dma >= 0; dma--) { channel = &frv_dma_channels[dma]; if (!(channel->flags & FRV_DMA_FLAGS_PAUSED)) continue; ioaddr = channel->ioaddr; cstr = __get_DMAC(ioaddr, CSTR); cstr &= ~(DMAC_CSTRx_FED | DMAC_CSTRx_INT); __set_DMAC(ioaddr, CSTR, cstr); cctr = __get_DMAC(ioaddr, CCTR); cctr |= DMAC_CCTRx_ACT; __set_DMAC(ioaddr, CCTR, cctr); channel->flags &= ~FRV_DMA_FLAGS_PAUSED; frv_set_dma_inprogress(dma); } write_unlock(&frv_dma_channels_lock); }

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/* end frv_dma_resume_all() */ EXPORT_SYMBOL(frv_dma_resume_all); /*****************************************************************************/ /* * dma status clear */
void frv_dma_status_clear(int dma) { unsigned long ioaddr = frv_dma_channels[dma].ioaddr; uint32_t cctr; ___set_DMAC(ioaddr, CSTR, 0); cctr = __get_DMAC(ioaddr, CCTR); }

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/* end frv_dma_status_clear() */ EXPORT_SYMBOL(frv_dma_status_clear);

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