alistair23-linux/drivers/gpu/drm/drm_pci.c

/* drm_pci.h -- PCI DMA memory management wrappers for DRM -*- linux-c -*- */
/**
 * \file drm_pci.c
 * \brief Functions and ioctls to manage PCI memory
 *
 * \warning These interfaces aren't stable yet.
 *
 * \todo Implement the remaining ioctl's for the PCI pools.
 * \todo The wrappers here are so thin that they would be better off inlined..
 *
 * \author José Fonseca <jrfonseca@tungstengraphics.com>
 * \author Leif Delgass <ldelgass@retinalburn.net>
 */

/*
 * Copyright 2003 José Fonseca.
 * Copyright 2003 Leif Delgass.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include "drmP.h"

/**********************************************************************/
/** \name PCI memory */
/*@{*/

/**
 * \brief Allocate a PCI consistent memory block, for DMA.
 */
drm_dma_handle_t *drm_pci_alloc(struct drm_device * dev, size_t size, size_t align)
{
	drm_dma_handle_t *dmah;
#if 1
	unsigned long addr;
	size_t sz;
#endif

	/* pci_alloc_consistent only guarantees alignment to the smallest
	 * PAGE_SIZE order which is greater than or equal to the requested size.
	 * Return NULL here for now to make sure nobody tries for larger alignment
	 */
	if (align > size)
		return NULL;

	dmah = kmalloc(sizeof(drm_dma_handle_t), GFP_KERNEL);
	if (!dmah)
		return NULL;

	dmah->size = size;
	dmah->vaddr = dma_alloc_coherent(&dev->pdev->dev, size, &dmah->busaddr, GFP_KERNEL | __GFP_COMP);

	if (dmah->vaddr == NULL) {
		kfree(dmah);
		return NULL;
	}

	memset(dmah->vaddr, 0, size);

	/* XXX - Is virt_to_page() legal for consistent mem? */
	/* Reserve */
	for (addr = (unsigned long)dmah->vaddr, sz = size;
	     sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
		SetPageReserved(virt_to_page(addr));
	}

	return dmah;
}

EXPORT_SYMBOL(drm_pci_alloc);

/**
 * \brief Free a PCI consistent memory block without freeing its descriptor.
 *
 * This function is for internal use in the Linux-specific DRM core code.
 */
void __drm_pci_free(struct drm_device * dev, drm_dma_handle_t * dmah)
{
#if 1
	unsigned long addr;
	size_t sz;
#endif

	if (dmah->vaddr) {
		/* XXX - Is virt_to_page() legal for consistent mem? */
		/* Unreserve */
		for (addr = (unsigned long)dmah->vaddr, sz = dmah->size;
		     sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
			ClearPageReserved(virt_to_page(addr));
		}
		dma_free_coherent(&dev->pdev->dev, dmah->size, dmah->vaddr,
				  dmah->busaddr);
	}
}

/**
 * \brief Free a PCI consistent memory block
 */
void drm_pci_free(struct drm_device * dev, drm_dma_handle_t * dmah)
{
	__drm_pci_free(dev, dmah);
	kfree(dmah);
}

EXPORT_SYMBOL(drm_pci_free);

#ifdef CONFIG_PCI
/**
 * Register.
 *
 * \param pdev - PCI device structure
 * \param ent entry from the PCI ID table with device type flags
 * \return zero on success or a negative number on failure.
 *
 * Attempt to gets inter module "drm" information. If we are first
 * then register the character device and inter module information.
 * Try and register, if we fail to register, backout previous work.
 */
int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
		    struct drm_driver *driver)
{
	struct drm_device *dev;
	int ret;

	DRM_DEBUG("\n");

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	ret = pci_enable_device(pdev);
	if (ret)
		goto err_g1;

	pci_set_master(pdev);

	dev->pdev = pdev;
	dev->dev = &pdev->dev;

	dev->pci_device = pdev->device;
	dev->pci_vendor = pdev->vendor;

#ifdef __alpha__
	dev->hose = pdev->sysdata;
#endif

	mutex_lock(&drm_global_mutex);

	if ((ret = drm_fill_in_dev(dev, ent, driver))) {
		printk(KERN_ERR "DRM: Fill_in_dev failed.\n");
		goto err_g2;
	}

	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
		pci_set_drvdata(pdev, dev);
		ret = drm_get_minor(dev, &dev->control, DRM_MINOR_CONTROL);
		if (ret)
			goto err_g2;
	}

	if ((ret = drm_get_minor(dev, &dev->primary, DRM_MINOR_LEGACY)))
		goto err_g3;

	if (dev->driver->load) {
		ret = dev->driver->load(dev, ent->driver_data);
		if (ret)
			goto err_g4;
	}

	/* setup the grouping for the legacy output */
	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
		ret = drm_mode_group_init_legacy_group(dev,
						&dev->primary->mode_group);
		if (ret)
			goto err_g4;
	}

	list_add_tail(&dev->driver_item, &driver->device_list);

	DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
		 driver->name, driver->major, driver->minor, driver->patchlevel,
		 driver->date, pci_name(pdev), dev->primary->index);

	mutex_unlock(&drm_global_mutex);
	return 0;

err_g4:
	drm_put_minor(&dev->primary);
err_g3:
	if (drm_core_check_feature(dev, DRIVER_MODESET))
		drm_put_minor(&dev->control);
err_g2:
	pci_disable_device(pdev);
err_g1:
	kfree(dev);
	mutex_unlock(&drm_global_mutex);
	return ret;
}
EXPORT_SYMBOL(drm_get_pci_dev);

/**
 * PCI device initialization. Called via drm_init at module load time,
 *
 * \return zero on success or a negative number on failure.
 *
 * Initializes a drm_device structures,registering the
 * stubs and initializing the AGP device.
 *
 * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 * after the initialization for driver customization.
 */
int drm_pci_init(struct drm_driver *driver)
{
	struct pci_dev *pdev = NULL;
	const struct pci_device_id *pid;
	int i;

	if (driver->driver_features & DRIVER_MODESET)
		return pci_register_driver(&driver->pci_driver);

	/* If not using KMS, fall back to stealth mode manual scanning. */
	for (i = 0; driver->pci_driver.id_table[i].vendor != 0; i++) {
		pid = &driver->pci_driver.id_table[i];

		/* Loop around setting up a DRM device for each PCI device
		 * matching our ID and device class.  If we had the internal
		 * function that pci_get_subsys and pci_get_class used, we'd
		 * be able to just pass pid in instead of doing a two-stage
		 * thing.
		 */
		pdev = NULL;
		while ((pdev =
			pci_get_subsys(pid->vendor, pid->device, pid->subvendor,
				       pid->subdevice, pdev)) != NULL) {
			if ((pdev->class & pid->class_mask) != pid->class)
				continue;

			/* stealth mode requires a manual probe */
			pci_dev_get(pdev);
			drm_get_pci_dev(pdev, pid, driver);
		}
	}
	return 0;
}

#else

int drm_pci_init(struct drm_driver *driver)
{
	return -1;
}

#endif
/*@}*/