BEST_dma_device.c File Reference

Char driver for mSGDMA. More...

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/cdev.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/string.h>
#include <asm/uaccess.h>
#include <linux/pci.h>
#include "BEST_PCIe.h"
#include "BEST_PCIe_internal.h"
#include "BEST_dma_device.h"
#include "msgdma/descriptor_regs.h"
#include "msgdma/csr_regs.h"

Macros
#define	debug_print(fmt, args...)   do { if (DEBUG_DMA_PRINT) printk( KERN_DEBUG fmt, ##args); } while (0)
#define	ceil(x, y)   ({ unsigned long __x = (x), __y = (y); (__x + __y - 1) / __y; })

Functions
	MODULE_LICENSE ("GPL")
void	dma_read (struct dma_dev_struct *dev, uint64_t read_addr, uint64_t write_addr, uint32_t len)
	Reads from DMA. More...
void	dma_enable_int (struct dma_dev_struct *dev)
	Enables DMA interrupt. More...
void	dma_disable_int (struct dma_dev_struct *dev)
	Disables DMA interrupt. More...
void	dma_reset (struct dma_dev_struct *dev)
	Resets DMA. More...
int	dma_char_open (struct inode *inode, struct file *file)
	Opens char device (stores dev struct in pirvate data) More...
ssize_t	dma_char_read (struct file *file, char __user *buf, size_t count, loff_t *pos)
	Reads from char device. More...
void	dma_advance_buf (struct dma_dev_struct *dev)
	Advacnes to next buffer, returns pointer to it. More...
int	dma_dev_create (struct dma_dev_struct *dev, struct class *best_class)
	Creates new DMA char device. More...
void	dma_dev_remove (struct dma_dev_struct *dev, struct class *best_class)
	Removes DMA char device. More...
int	dma_dev_allocate_buffers (struct pci_dev *dev, struct dma_dev_struct *dma)
	Allocates DMA buffers. More...
void	dma_dev_free_buffers (struct pci_dev *dev, struct dma_dev_struct *dma)
	Frees DMA buffers. More...

Variables
static const struct file_operations	dma_char_fops

Detailed Description

Char driver for mSGDMA.

Author

Jan Marjanovic (j.mar.nosp@m.jano.nosp@m.vic@c.nosp@m.aene.nosp@m.ls.co.nosp@m.m)

Date

June 2014

Function Documentation

void dma_advance_buf

(

struct dma_dev_struct *

dev

)

Advacnes to next buffer, returns pointer to it.

Parameters

dev	DMA structure
buf_to_write	Returns address of a buffer to write to

int dma_char_open	(	struct inode *	inode,
		struct file *	file
	)

Opens char device (stores dev struct in pirvate data)

Parameters

inode	Index node structure
file	File structure

Returns

0 on success, negative number on fail

ssize_t dma_char_read	(	struct file *	file,
		char __user *	buf,
		size_t	count,
		loff_t *	pos
	)

Reads from char device.

Parameters

file	File structure (path, ...)
buf	Buffer to read to
count	Number of bytes to read
pos

Returns

Numbers of bytes successfully read

int dma_dev_allocate_buffers	(	struct pci_dev *	dev,
		struct dma_dev_struct *	dma
	)

Allocates DMA buffers.

Parameters

dev	PCI device
dma	DMA strucutre to allocate memory

Fields buf_number and buf_len must have valid values

int dma_dev_create	(	struct dma_dev_struct *	dev,
		struct class *	best_class
	)

Creates new DMA char device.

Parameters

dev	Structure with DMA info
best_class	Class which this device will be part of

Creates new char device, which represents FPGA mSGDMA Allowed operation on device is read(), which returns most recent data from buffers

void dma_dev_free_buffers	(	struct pci_dev *	dev,
		struct dma_dev_struct *	dma
	)

Frees DMA buffers.

Parameters

dev	PCI device
dma	DMA strucutre to allocate memory

void dma_dev_remove	(	struct dma_dev_struct *	dev,
		struct class *	best_class
	)

Removes DMA char device.

Parameters

dev	Structure with DMA info
best_class	Class which this device will be part of

void dma_disable_int

(

struct dma_dev_struct *

dev

)

Disables DMA interrupt.

Parameters

board

Pointer to structure with board specific data

void dma_enable_int

(

struct dma_dev_struct *

dev

)

Enables DMA interrupt.

Parameters

board

Pointer to structure with board specific data

void dma_read	(	struct dma_dev_struct *	dev,
		uint64_t	read_addr,
		uint64_t	write_addr,
		uint32_t	len
	)

Reads from DMA.

Parameters

board	Pointer to structure with board specific data
read_addr	Address to read from (Avalon MM for this application)
write_addr	Address to write to (should be in DMA space, physical)
len	Number of bytes to transfer

void dma_reset

(

struct dma_dev_struct *

dev

)

Resets DMA.

Parameters

board

Pointer to structure with board specific data

Variable Documentation

const struct file_operations dma_char_fops

static

Initial value:

= {
    .owner      = THIS_MODULE,
    .open       = dma_char_open,
    .read       = dma_char_read,
    
}