/*
* Intel GTT (Graphics Translation Table) routines
*
* Caveat: This driver implements the linux agp interface, but this is far from
* a agp driver! GTT support ended up here for purely historical reasons: The
* old userspace intel graphics drivers needed an interface to map memory into
* the GTT. And the drm provides a default interface for graphic devices sitting
* on an agp port. So it made sense to fake the GTT support as an agp port to
* avoid having to create a new api.
*
* With gem this does not make much sense anymore, just needlessly complicates
* the code. But as long as the old graphics stack is still support, it's stuck
* here.
*
* /fairy-tale-mode off
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/pagemap.h>
#include <linux/agp_backend.h>
#include <linux/delay.h>
#include <asm/smp.h>
#include "agp.h"
#include "intel-agp.h"
#include <drm/intel-gtt.h>
/*
* If we have Intel graphics, we're not going to have anything other than
* an Intel IOMMU. So make the correct use of the PCI DMA API contingent
* on the Intel IOMMU support (CONFIG_INTEL_IOMMU).
* Only newer chipsets need to bother with this, of course.
*/
#ifdef CONFIG_INTEL_IOMMU
#define USE_PCI_DMA_API 1
#else
#define USE_PCI_DMA_API 0
#endif
struct intel_gtt_driver {
unsigned int gen : 8;
unsigned int is_g33 : 1;
unsigned int is_pineview : 1;
unsigned int is_ironlake : 1;
unsigned int has_pgtbl_enable : 1;
unsigned int dma_mask_size : 8;
/* Chipset specific GTT setup */
int (*setup)(void);
/* This should undo anything done in ->setup() save the unmapping
* of the mmio register file, that's done in the generic code. */
void (*cleanup)(void);
void (*write_entry)(dma_addr_t addr, unsigned int entry, unsigned int flags);
/* Flags is a more or less chipset specific opaque value.
* For chipsets that need to support old ums (non-gem) code, this
* needs to be identical to the various supported agp memory types! */
bool (*check_flags)(unsigned int