path: root/drivers/dma/ppc460ex_4chan_dma.c

/*
 * Copyright(c) 2008 Applied Micro Circuits Corporation(AMCC). All rights reserved.
 *
 * 
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * The full GNU General Public License is included in this distribution in the
 * file called COPYING.
 */


#include <linux/init.h>
#include <linux/module.h>
#include <linux/async_tx.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/of_platform.h>
#include <linux/uaccess.h>
#include <linux/proc_fs.h>
#include <asm/dcr-regs.h>
#include <asm/dcr.h>
#include "ppc460ex_4chan_dma.h"



#ifdef DEBUG_TEST
#define dma_pr printk
#else
#define dma_pr
#endif 
#define TEST_SIZE 12


ppc460ex_plb_dma_dev_t *adev;



int ppc460ex_get_dma_channel(void)
{
	int i;
	unsigned int status = 0;
	status = mfdcr(DCR_DMA2P40_SR);

	for(i=0; i<MAX_PPC460EX_DMA_CHANNELS; i++) {
		if ((status & (1 >> (20+i))) == 0)
			return i;
	}
	return -ENODEV;
}


int ppc460ex_get_dma_status(void)
{
  return (mfdcr(DCR_DMA2P40_SR));

}


int ppc460ex_set_src_addr(int ch_id, phys_addr_t src_addr)
{

  if (ch_id >= MAX_PPC460EX_DMA_CHANNELS) {
    printk("%s: bad channel %d\n", __FUNCTION__, ch_id);
    return DMA_STATUS_BAD_CHANNEL;
  }


#ifdef PPC4xx_DMA_64BIT
  mtdcr(DCR_DMA2P40_SAH0 + ch_id*8, src_addr >> 32);
#endif
  mtdcr(DCR_DMA2P40_SAL0 + ch_id*8, (u32)src_addr);

  return DMA_STATUS_GOOD;
}

int ppc460ex_set_dst_addr(int ch_id, phys_addr_t dst_addr)
{

  if (ch_id >= MAX_PPC460EX_DMA_CHANNELS) {
    printk(KERN_ERR "%s: bad channel %d\n", __FUNCTION__, ch_id);
    return DMA_STATUS_BAD_CHANNEL;
  }

#ifdef PPC4xx_DMA_64BIT
  mtdcr(DCR_DMA2P40_DAH0 + ch_id*8, dst_addr >> 32);
#endif
  mtdcr(DCR_DMA2P40_DAL0 + ch_id*8, (u32)dst_addr);
  
  return DMA_STATUS_GOOD;
}



/*
 * Sets the dma mode for single DMA transfers only.
 * For scatter/gather transfers, the mode is passed to the
 * alloc_dma_handle() function as one of the parameters.
 *
 * The mode is simply saved and used later.  This allows
 * the driver to call set_dma_mode() and set_dma_addr() in
 * any order.
 *
 * Valid mode values are:
 *
 * DMA_MODE_READ          peripheral to memory
 * DMA_MODE_WRITE         memory to peripheral
 * DMA_MODE_MM            memory to memory
 * DMA_MODE_MM_DEVATSRC   device-paced memory to memory, device at src
 * DMA_MODE_MM_DEVATDST   device-paced memory to memory, device at dst
 */
int ppc460ex_set_dma_mode(ppc460ex_plb_dma_dev_t *adev, unsigned int ch_id, unsigned int mode)
{
  
  ppc460ex_plb_dma_ch_t *dma_chan = adev->chan[ch_id]; 
  
  if (ch_id >= MAX_PPC460EX_DMA_CHANNELS) {
    printk("%s: bad channel %d\n", __FUNCTION__, dma_chan->chan_id);
    return DMA_STATUS_BAD_CHANNEL;
  }

  dma_chan->mode = mode;
  return DMA_STATUS_GOOD;
}




/*
 * Sets the DMA Count register. Note that 'count' is in bytes.
 * However, the DMA Count register counts the number of "transfers",
 * where each transfer is equal to the bus width.  Thus, count
 * MUST be a multiple of the bus width.
 */
void ppc460ex_set_dma_count(ppc460ex_plb_dma_dev_t *adev, unsigned int ch_id, unsigned int count)
{
  ppc460ex_plb_dma_ch_t *dma_chan = adev->chan[ch_id];
  
//#ifdef DEBUG_4xxDMA

	{
		int error = 0;
		switch (dma_chan->pwidth) {
		case PW_8:
			break;
		case PW_16:
			if (count & 0x1)
				error = 1;
			break;
		case PW_32:
			if (count & 0x3)
				error = 1;
			break;
		case PW_64:
			if (count & 0x7)
				error = 1;
			break;
		 
		case PW_128:
		        if (count & 0xf)
			        error = 1;
			break