video1394.c

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/*
 * video1394.c - video driver for OHCI 1394 boards
 * Copyright (C)1999,2000 Sebastien Rougeaux <[e-mail]>
 *
 * 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.
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/fs.h>
#include <linux/poll.h>
#include <linux/smp_lock.h>
#include <asm/byteorder.h>
#include <asm/atomic.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/proc_fs.h>
#include <linux/tqueue.h>
#include <linux/delay.h>

#include <asm/pgtable.h>
#include <asm/page.h>
#include <linux/sched.h>
#include <asm/segment.h>
#include <linux/types.h>
#include <linux/wrapper.h>
#include <linux/vmalloc.h>

#include "ieee1394.h"
#include "ieee1394_types.h"
#include "hosts.h"
#include "ieee1394_core.h"
#include "video1394.h"

#include "ohci1394.h"

#define VIDEO1394_MAJOR 172
#define ISO_CHANNELS 64
#define ISO_RECEIVE 0
#define ISO_TRANSMIT 1

#ifndef virt_to_page
#define virt_to_page(x) MAP_NR(x)
#endif

#ifndef vmalloc_32
#define vmalloc_32(x) vmalloc(x)
#endif

struct it_dma_prg {
	struct dma_cmd begin;
	quadlet_t data[4];
	struct dma_cmd end;
	quadlet_t pad[4]; /* FIXME: quick hack for memory alignment */
};

struct dma_iso_ctx {
	struct ti_ohci *ohci;
	int ctx;
	int channel;
	int last_buffer;
	unsigned int num_desc;
	unsigned int buf_size;
	unsigned int frame_size;
	unsigned int packet_size;
	unsigned int left_size;
	unsigned int nb_cmd;
	unsigned char *buf;
        struct dma_cmd **ir_prg;
	struct it_dma_prg **it_prg;
	unsigned int *buffer_status;
	int ctrlClear;
	int ctrlSet;
	int cmdPtr;
	int ctxMatch;
	wait_queue_head_t waitq;
        spinlock_t lock;
};

struct video_card {
	struct ti_ohci *ohci;

	struct dma_iso_ctx **ir_context;
	struct dma_iso_ctx **it_context;
	struct dma_iso_ctx *current_ctx;
};

#ifdef CONFIG_IEEE1394_VERBOSEDEBUG
#define VIDEO1394_DEBUG
#endif

#ifdef DBGMSG
#undef DBGMSG
#endif

#ifdef VIDEO1394_DEBUG
#define DBGMSG(card, fmt, args...) \
printk(KERN_INFO "video1394_%d: " fmt "\n" , card , ## args)
#else
#define DBGMSG(card, fmt, args...)
#endif

/* print general (card independent) information */
#define PRINT_G(level, fmt, args...) \
printk(level "video1394: " fmt "\n" , ## args)

/* print card specific information */
#define PRINT(level, card, fmt, args...) \
printk(level "video1394_%d: " fmt "\n" , card , ## args)

void irq_handler(int card, quadlet_t isoRecvIntEvent, 
		 quadlet_t isoXmitIntEvent);

static struct video_card video_cards[MAX_OHCI1394_CARDS];
static int num_of_video_cards = 0;
static struct video_template video_tmpl = { irq_handler };

/* Taken from bttv.c */
/*******************************/
/* Memory management functions */
/*******************************/

#define MDEBUG(x)	do { } while(0)		/* Debug memory management */

/* [DaveM] I've recoded most of this so that:
 * 1) It's easier to tell what is happening
 * 2) It's more portable, especially for translating things
 *    out of vmalloc mapped areas in the kernel.
 * 3) Less unnecessary translations happen.
 *
 * The code used to assume that the kernel vmalloc mappings
 * existed in the page tables of every process, this is simply
 * not guarenteed.  We now use pgd_offset_k which is the
 * defined way to get at the kernel page tables.
 */

#if LINUX_VERSION_CODE < KERNEL_VERSION(2,3,0)
#define page_address(x)	(x)
#endif

/* Given PGD from the address space's page table, return the kernel
 * virtual mapping of the physical memory mapped at ADR.
 */
static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr)
{
        unsigned long ret = 0UL;
	pmd_t *pmd;
	pte_t *ptep, pte;
  
	if (!pgd_none(*pgd)) {
                pmd = pmd_offset(pgd, adr);
                if (!pmd_none(*pmd)) {
                        ptep = pte_offset(pmd, adr);
                        pte = *ptep;
                        if(pte_present(pte)) {
				ret = (unsigned long) page_address(pte_page(pte));
                                ret |= (adr & (PAGE_SIZE - 1));
			}
                }
        }
        MDEBUG(printk("uv2kva(%lx-->%lx)", adr, ret));
	return ret;
}

static inline unsigned long uvirt_to_bus(unsigned long adr) 
{
        unsigned long kva, ret;

        kva = uvirt_to_kva(pgd_offset(current->mm, adr), adr);
	ret = virt_to_bus((void *)kva);
        MDEBUG(printk("uv2b(%lx-->%lx)", adr, ret));
        return ret;
}

static inline unsigned long kvirt_to_bus(unsigned long adr) 
{
        unsigned long va, kva, ret;

        va = VMALLOC_VMADDR(adr);
        kva = uvirt_to_kva(pgd_offset_k(va), va);
	ret = virt_to_bus((void *)kva);
        MDEBUG(printk("kv2b(%lx-->%lx)", adr, ret));
        return ret;
}

/* Here we want the physical address of the memory.
 * This is used when initializing the contents of the
 * area and marking the pages as reserved.
 */
static inline unsigned long kvirt_to_pa(unsigned long adr) 
{
        unsigned long va, kva, ret;

        va = VMALLOC_VMADDR(adr);
        kva = uvirt_to_kva(pgd_offset_k(va), va);
	ret = __pa(kva);
        MDEBUG(printk("kv2pa(%lx-->%lx)", adr, ret));
        return ret;
}

static void * rvmalloc(unsigned long size)
{
	void * mem;
	unsigned long adr, page;
        
	mem=vmalloc_32(size);
	if (mem) 
	{
		memset(mem, 0, size); /* Clear the ram out, 
					 no junk to the user */
	        adr=(unsigned long) mem;
		while (size > 0) 
                {
	                page = kvirt_to_pa(adr);
			mem_map_reserve(virt_to_page(__va(page)));
			adr+=PAGE_SIZE;
			size-=PAGE_SIZE;
		}
	}
	return mem;
}

static void rvfree(void * mem, unsigned long size)
{
        unsigned long adr, page;
        
	if (mem) 
	{
	        adr=(unsigned long) mem;
		while (size > 0) 
                {
	                page = kvirt_to_pa(adr);
			mem_map_unreserve(virt_to_page(__va(page)));
			adr+=PAGE_SIZE;
			size-=PAGE_SIZE;
		}
		vfree(mem);
	}
}

static int free_dma_iso_ctx(struct dma_iso_ctx **d)
{
	int i;
	struct ti_ohci *ohci;
	
	if ((*d)==NULL) return -1;

	ohci = (struct ti_ohci *)(*d)->ohci;

	DBGMSG(ohci->id, "Freeing dma_iso_ctx %d", (*d)->ctx);

	ohci1394_stop_context(ohci, (*d)->ctrlClear, NULL);

	if ((*d)->buf) rvfree((void *)(*d)->buf, 
			      (*d)->num_desc * (*d)->buf_size);

	if ((*d)->ir_prg) {
		for (i=0;i<(*d)->num_desc;i++) 
			if ((*d)->ir_prg[i]) kfree((*d)->ir_prg[i]);
		kfree((*d)->ir_prg);
	}

	if ((*d)->it_prg) {
		for (i=0;i<(*d)->num_desc;i++) 
			if ((*d)->it_prg[i]) kfree((*d)->it_prg[i]);
		kfree((*d)->it_prg);
	}

	if ((*d)->buffer_status)
		kfree((*d)->buffer_status);
	
	kfree(*d);
	*d = NULL;

	return 0;
}

static struct dma_iso_ctx *
alloc_dma_iso_ctx(struct ti_ohci *ohci, int type, int ctx, int num_desc,
		  int buf_size, int channel, unsigned int packet_size)
{
	struct dma_iso_ctx *d=NULL;
	int i;

	d = (struct dma_iso_ctx *)kmalloc(sizeof(struct dma_iso_ctx), 
					  GFP_KERNEL);
	memset(d, 0, sizeof(struct dma_iso_ctx));

	if (d==NULL) {
		PRINT(KERN_ERR, ohci->id, "failed to allocate dma_iso_ctx");
		return NULL;
	}

	d->ohci = (void *)ohci;
	d->ctx = ctx;
	d->channel = channel;
	d->num_desc = num_desc;
	d->frame_size = buf_size;
	if (buf_size%PAGE_SIZE) 
		d->buf_size = buf_size + PAGE_SIZE - (buf_size%PAGE_SIZE);
	else
		d->buf_size = buf_size;
	d->last_buffer = -1;
	d->buf = NULL;
	d->ir_prg = NULL;
	init_waitqueue_head(&d->waitq);

	d->buf = rvmalloc(d->num_desc * d->buf_size);

	if (d->buf == NULL) {
		PRINT(KERN_ERR, ohci->id, "failed to allocate dma buffer");
		free_dma_iso_ctx(&d);
		return NULL;
	}
	memset(d->buf, 0, d->num_desc * d->buf_size);

	if (type == ISO_RECEIVE) {
		d->ctrlSet = OHCI1394_IsoRcvContextControlSet+32*d->ctx;
		d->ctrlClear = OHCI1394_IsoRcvContextControlClear+32*d->ctx;
		d->cmdPtr = OHCI1394_IsoRcvCommandPtr+32*d->ctx;
		d->ctxMatch = OHCI1394_IsoRcvContextMatch+32*d->ctx;

		d->ir_prg = kmalloc(d->num_desc * sizeof(struct dma_cmd *), 
				    GFP_KERNEL);

		if (d->ir_prg == NULL) {
			PRINT(KERN_ERR, ohci->id, 
			      "failed to allocate dma ir prg");
			free_dma_iso_ctx(&d);
			return NULL;
		}
		memset(d->ir_prg, 0, d->num_desc * sizeof(struct dma_cmd *));
	
		d->nb_cmd = d->buf_size / PAGE_SIZE + 1;
		d->left_size = (d->frame_size % PAGE_SIZE) ?
			d->frame_size % PAGE_SIZE : PAGE_SIZE;

		for (i=0;i<d->num_desc;i++) {
			d->ir_prg[i] = kmalloc(d->nb_cmd * 
					       sizeof(struct dma_cmd), 
					       GFP_KERNEL);
			if (d->ir_prg[i] == NULL) {
				PRINT(KERN_ERR, ohci->id, 
				      "failed to allocate dma ir prg");
				free_dma_iso_ctx(&d);
				return NULL;
			}
		}
	}
	else {  /* ISO_TRANSMIT */
		d->ctrlSet = OHCI1394_IsoXmitContextControlSet+16*d->ctx;
		d->ctrlClear = OHCI1394_IsoXmitContextControlClear+16*d->ctx;
		d->cmdPtr = OHCI1394_IsoXmitCommandPtr+16*d->ctx;

		d->it_prg = kmalloc(d->num_desc * sizeof(struct it_dma_prg *), 
				    GFP_KERNEL);

		if (d->it_prg == NULL) {
			PRINT(KERN_ERR, ohci->id, 
			      "failed to allocate dma it prg");
			free_dma_iso_ctx(&d);
			return NULL;
		}
		memset(d->it_prg, 0, d->num_desc*sizeof(struct it_dma_prg *));
		
		d->packet_size = packet_size;

		if (PAGE_SIZE % packet_size || packet_size>4096) {
			PRINT(KERN_ERR, ohci->id, 
			      "Packet size %d not yet supported\n",
			      packet_size);
			free_dma_iso_ctx(&d);
			return NULL;
		}

		d->nb_cmd = d->frame_size / d->packet_size;
		if (d->frame_size % d->packet_size) {
			d->nb_cmd++;
			d->left_size = d->frame_size % d->packet_size;
		}
		else
			d->left_size = d->packet_size;

		for (i=0;i<d->num_desc;i++) {
			d->it_prg[i] = kmalloc(d->nb_cmd * 
					       sizeof(struct it_dma_prg), 
					       GFP_KERNEL);
			if (d->it_prg[i] == NULL) {
				PRINT(KERN_ERR, ohci->id, 
				      "failed to allocate dma it prg");
				free_dma_iso_ctx(&d);
				return NULL;
			}
		}
	}

	d->buffer_status = kmalloc(d->num_desc * sizeof(unsigned int),
				   GFP_KERNEL);

	if (d->buffer_status == NULL) {
		PRINT(KERN_ERR, ohci->id, "failed to allocate dma ir prg");
		free_dma_iso_ctx(&d);
		return NULL;
	}
	memset(d->buffer_status, 0, d->num_desc * sizeof(unsigned int));
	
        spin_lock_init(&d->lock);

	PRINT(KERN_INFO, ohci->id, "Iso %s DMA: %d buffers "
	      "of size %d allocated for a frame size %d, each with %d prgs",
	      (type==ISO_RECEIVE) ? "receive" : "transmit",
	      d->num_desc, d->buf_size, d->frame_size, d->nb_cmd);

	return d;
}

static void reset_ir_status(struct dma_iso_ctx *d, int n)
{
	int i;
	d->ir_prg[n][0].status = 4;
	d->ir_prg[n][1].status = PAGE_SIZE-4;
	for (i=2;i<d->nb_cmd-1;i++)
		d->ir_prg[n][i].status = PAGE_SIZE;
	d->ir_prg[n][i].status = d->left_size;
}

static void initialize_dma_ir_prg(struct dma_iso_ctx *d, int n, int flags)
{
	struct dma_cmd *ir_prg = d->ir_prg[n];
	unsigned long buf = (unsigned long)d->buf+n*d->buf_size;
	int i;

	/* the first descriptor will read only 4 bytes */
	ir_prg[0].control = (0x280C << 16) | 4;