Commit ec722b00 authored by YuriNenakhov's avatar YuriNenakhov
Browse files

DMA support initial

parent 0082c20c

src/drivers/elphel/Kconfig

+16 −10
Original line number Diff line number Diff line
@@ -4,9 +4,15 @@ 
                                                                                                                                     

menu "Elphel devices"

config ELPHEL393

	tristate "Support Elphel 10393 board voltage regulator"

        tristate "Support Elphel 10393 board voltage regulator, DMA memory allocator"

# add more

#       depends on I2C && SYSFS

        help

          Say Y here if you have a Elphel board 10393.



config ELPHELDRVONMICROZED

        tristate "Provide only Elphel features which are compatible with Microzed"

        help

          Say Y here if you debug Elpel camera code on Microzed board.



endmenu

src/drivers/elphel/Makefile

+7 −5
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@@ -3,3 +3,5 @@ 
#                                                                                                                                    

                                                                                                                                     

obj-$(CONFIG_ELPHEL393)         += elphel393-pwr.o  

obj-$(CONFIG_ELPHEL393)         += elphel393-mem.o  

obj-$(CONFIG_ELPHELDRVONMICROZED)          += elphel393-mem.o

src/drivers/elphel/elphel393-mem.c

0 → 100644
+135 −0
Original line number Diff line number Diff line 
#include <linux/module.h>

#include <linux/init.h>

#include <linux/of.h>

#include <linux/kernel.h>

#include <linux/bootmem.h>

#include <linux/platform_device.h>

#include <linux/dma-mapping.h>

#include <linux/dma-direction.h>

#include <asm/dma-mapping.h>



#define SYSFS_PERMISSIONS         0644 /* default permissions for sysfs files */

#define SYSFS_READONLY            0444





static ssize_t get_paddr(struct device *dev, struct device_attribute *attr, char *buf);



struct elphel_buf_t

{

	void *vaddr;

	dma_addr_t paddr;

	ssize_t size;

};



static struct elphel_buf_t elphel_buf = {

	.vaddr = NULL,

	.paddr = 0,

	.size = 0

};



static int __init elphelmem_init(void)

{

    struct device_node *node;

	const __be32 *bufsize_be;



	printk("======== Allocating memory buffer ========\n");



	node = of_find_node_by_name(NULL, "elphel393-mem");

	if (!node)

	{

		printk("ERROR: No node found\n");

		return -ENODEV;

	}



	bufsize_be = (__be32 *)of_get_property(node, "memsize", NULL);

	elphel_buf.size = be32_to_cpup(bufsize_be);



	elphel_buf.vaddr = dma_alloc_coherent(NULL,(elphel_buf.size*PAGE_SIZE),&(elphel_buf.paddr),GFP_KERNEL);



    if(elphel_buf.paddr)

    {

    	printk("Allocated %u pages at address %x\n", (u32)elphel_buf.size, (u32)elphel_buf.paddr);

    }

    else printk("ERROR allocating memory buffer");



    return 0;

}



static void __exit elphelmem_exit(void)

{

    printk("Goodbye Cruel World!\n");

}







// SYSFS



static ssize_t get_paddr(struct device *dev, struct device_attribute *attr, char *buf)

{

	return sprintf(buf,"%x\n", (u32)elphel_buf.paddr);

}



static ssize_t get_size(struct device *dev, struct device_attribute *attr, char *buf)

{

	return sprintf(buf,"%u\n", elphel_buf.size);

}

static DEVICE_ATTR(buffer_address,  SYSFS_PERMISSIONS & SYSFS_READONLY,    get_paddr,          NULL);

static DEVICE_ATTR(buffer_pages,  SYSFS_PERMISSIONS & SYSFS_READONLY,    get_size,          NULL);



static struct attribute *root_dev_attrs[] = {

		&dev_attr_buffer_address.attr,

		&dev_attr_buffer_pages.attr,

	    NULL

};



static const struct attribute_group dev_attr_root_group = {

	.attrs = root_dev_attrs,

	.name  = NULL,

};



static int elphel393_mem_sysfs_register(struct platform_device *pdev)

{

	int retval=0;

	struct device *dev = &pdev->dev;

	if (&dev->kobj) {

		if (((retval = sysfs_create_group(&dev->kobj, &dev_attr_root_group)))<0) return retval;

	}

	return retval;

}



static int elphel393_mem_probe(struct platform_device *pdev)

{

	elphel393_mem_sysfs_register(pdev);

	dev_info(&pdev->dev,"Probing elphel393-mem\n");

	return 0;

}



static int elphel393_mem_remove(struct platform_device *pdev)

{

	dev_info(&pdev->dev,"Removing elphel393-mem");

	return 0;

}



static struct of_device_id elphel393_mem_of_match[] = {

	{ .compatible = "elphel,elphel393-mem-1.00", },

	{ /* end of table */}

};

MODULE_DEVICE_TABLE(of, elphel393_pwr_of_match);



static struct platform_driver elphel393_mem = {

	.probe   = elphel393_mem_probe,

	.remove  = elphel393_mem_remove,

	.driver  = {

		.name  = "elphel393-mem",

		.owner = THIS_MODULE,

		.of_match_table = elphel393_mem_of_match,

		.pm = NULL, /* power management */

	},

};



module_platform_driver(elphel393_mem);

module_init(elphelmem_init);

module_exit(elphelmem_exit);

MODULE_LICENSE("GPL");