path: root/drivers/media/video/bt8xx/bttv-risc.c

/*

    bttv-risc.c  --  interfaces to other kernel modules

    bttv risc code handling
	- memory management
	- generation

    (c) 2000-2003 Gerd Knorr <kraxel@bytesex.org>

    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., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/vmalloc.h>
#include <linux/interrupt.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <media/v4l2-ioctl.h>

#include "bttvp.h"

#define VCR_HACK_LINES 4

/* ---------------------------------------------------------- */
/* risc code generators                                       */

int
bttv_risc_packed(struct bttv *btv, struct btcx_riscmem *risc,
		 struct scatterlist *sglist,
		 unsigned int offset, unsigned int bpl,
		 unsigned int padding, unsigned int skip_lines,
		 unsigned int store_lines)
{
	u32 instructions,line,todo;
	struct scatterlist *sg;
	__le32 *rp;
	int rc;

	/* estimate risc mem: worst case is one write per page border +
	   one write per scan line + sync + jump (all 2 dwords).  padding
	   can cause next bpl to start close to a page border.  First DMA
	   region may be smaller than PAGE_SIZE */
	instructions  = skip_lines * 4;
	instructions += (1 + ((bpl + padding) * store_lines)
			 / PAGE_SIZE + store_lines) * 8;
	instructions += 2 * 8;
	if ((rc = btcx_riscmem_alloc(btv->c.pci,risc,instructions)) < 0)
		return rc;

	/* sync instruction */
	rp = risc->cpu;
	*(rp++) = cpu_to_le32(BT848_RISC_SYNC|BT848_FIFO_STATUS_FM1);
	*(rp++) = cpu_to_le32(0);

	while (skip_lines-- > 0) {
		*(rp++) = cpu_to_le32(BT848_RISC_SKIP | BT848_RISC_SOL |
				      BT848_RISC_EOL | bpl);
	}

	/* scan lines */
	sg = sglist;
	for (line = 0; line < store_lines; line++) {
		if ((btv->opt_vcr_hack) &&
		    (line >= (store_lines - VCR_HACK_LINES)))
			continue;
		while (offset && offset >= sg_dma_len(sg)) {
			offset -= sg_dma_len(sg);
			sg++;
		}
		if (bpl <= sg_dma_len(sg)-offset) {
			/* fits into current chunk */
			*(rp++)=cpu_to_le32(BT848_RISC_WRITE|BT848_RISC_SOL|
					    BT848_RISC_EOL|bpl);
			*(rp++)=cpu_to_le32(sg_dma_address(sg)+offset);
			offset+=bpl;
		} else {
			/* scanline needs to be splitted */
			todo = bpl;
			*(rp++)=cpu_to_le32(BT848_RISC_WRITE|BT848_RISC_SOL|
					    (sg_dma_len(sg)-offset));
			*(rp++)=cpu_to_le32(sg_dma_address(sg)+offset);
			todo -= (sg_dma_len(sg)-offset);
			offset = 0;
			sg++;
			while (todo > sg_dma_len(sg)) {
				*(rp++)=cpu_to_le32(BT848_RISC_WRITE|
						    sg_dma_len(sg));
				*(rp++)=cpu_to_le32(sg_dma_address(sg));
				todo -= sg_dma_len(sg);
				sg++;
			}
			*(rp++)=cpu_to_le32(BT848_RISC_WRITE|BT848_RISC_EOL|
					    todo);
			*(rp++)=cpu_to_le32(sg_dma_address(sg));
			offset += todo;
		}
		offset += padding;
	}

	/* save pointer to jmp instruction address */
	risc->jmp = rp;
	BUG_ON((risc->jmp - risc->cpu + 2) * sizeof(*risc->cpu) > risc->size);
	return 0;
}

static int
bttv_risc_planar(struct bttv *btv, struct btcx_riscmem *risc,
		 struct scatterlist *sglist,
		 unsigned int yoffset,  unsigned int ybpl,
		 unsigned int ypadding, unsigned int ylines,
		 unsigned int uoffset,  unsigned int voffset,
		 unsigned int hshift,   unsigned int vshift,
		 unsigned int cpadding)
{
	unsigned int instructions,line,todo,ylen,chroma;
	__le32 *rp;
	u32 ri;
	struct scatterlist *ysg;
	struct scatterlist *usg;
	struct scatterlist *vsg;
	int topfield = (0 == yoffset);
	int rc;

	/* estimate risc mem: worst case is one write per page border +
	   one write per scan line (5 dwords)
	   plus sync + jump (2 dwords) */
	instructions  = ((3 + (ybpl + ypadding) * ylines * 2)
			 / PAGE_SIZE) + ylines;
	instructions += 2;
	if ((rc = btcx_riscmem_alloc(btv->c.pci,risc,instructions*4