linux/drivers/gpu/drm/omapdrm/omap_gem.c
Christian König c67e62790f drm/prime: split array import functions v4
Mapping the imported pages of a DMA-buf into an userspace process
doesn't work as expected.

But we have reoccurring requests on this approach, so split the
functions for this and  document that dma_buf_mmap() needs to be used
instead.

v2: split it into two functions
v3: rebased on latest changes
v4: update commit message a bit

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/403838/
2020-11-30 15:00:45 +01:00

1434 lines
37 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2011 Texas Instruments Incorporated - https://www.ti.com/
* Author: Rob Clark <rob.clark@linaro.org>
*/
#include <linux/dma-mapping.h>
#include <linux/seq_file.h>
#include <linux/shmem_fs.h>
#include <linux/spinlock.h>
#include <linux/pfn_t.h>
#include <drm/drm_prime.h>
#include <drm/drm_vma_manager.h>
#include "omap_drv.h"
#include "omap_dmm_tiler.h"
/*
* GEM buffer object implementation.
*/
/* note: we use upper 8 bits of flags for driver-internal flags: */
#define OMAP_BO_MEM_DMA_API 0x01000000 /* memory allocated with the dma_alloc_* API */
#define OMAP_BO_MEM_SHMEM 0x02000000 /* memory allocated through shmem backing */
#define OMAP_BO_MEM_DMABUF 0x08000000 /* memory imported from a dmabuf */
struct omap_gem_object {
struct drm_gem_object base;
struct list_head mm_list;
u32 flags;
/** width/height for tiled formats (rounded up to slot boundaries) */
u16 width, height;
/** roll applied when mapping to DMM */
u32 roll;
/** protects dma_addr_cnt, block, pages, dma_addrs and vaddr */
struct mutex lock;
/**
* dma_addr contains the buffer DMA address. It is valid for
*
* - buffers allocated through the DMA mapping API (with the
* OMAP_BO_MEM_DMA_API flag set)
*
* - buffers imported from dmabuf (with the OMAP_BO_MEM_DMABUF flag set)
* if they are physically contiguous (when sgt->orig_nents == 1)
*
* - buffers mapped through the TILER when dma_addr_cnt is not zero, in
* which case the DMA address points to the TILER aperture
*
* Physically contiguous buffers have their DMA address equal to the
* physical address as we don't remap those buffers through the TILER.
*
* Buffers mapped to the TILER have their DMA address pointing to the
* TILER aperture. As TILER mappings are refcounted (through
* dma_addr_cnt) the DMA address must be accessed through omap_gem_pin()
* to ensure that the mapping won't disappear unexpectedly. References
* must be released with omap_gem_unpin().
*/
dma_addr_t dma_addr;
/**
* # of users of dma_addr
*/
refcount_t dma_addr_cnt;
/**
* If the buffer has been imported from a dmabuf the OMAP_DB_DMABUF flag
* is set and the sgt field is valid.
*/
struct sg_table *sgt;
/**
* tiler block used when buffer is remapped in DMM/TILER.
*/
struct tiler_block *block;
/**
* Array of backing pages, if allocated. Note that pages are never
* allocated for buffers originally allocated from contiguous memory
*/
struct page **pages;
/** addresses corresponding to pages in above array */
dma_addr_t *dma_addrs;
/**
* Virtual address, if mapped.
*/
void *vaddr;
};
#define to_omap_bo(x) container_of(x, struct omap_gem_object, base)
/* To deal with userspace mmap'ings of 2d tiled buffers, which (a) are
* not necessarily pinned in TILER all the time, and (b) when they are
* they are not necessarily page aligned, we reserve one or more small
* regions in each of the 2d containers to use as a user-GART where we
* can create a second page-aligned mapping of parts of the buffer
* being accessed from userspace.
*
* Note that we could optimize slightly when we know that multiple
* tiler containers are backed by the same PAT.. but I'll leave that
* for later..
*/
#define NUM_USERGART_ENTRIES 2
struct omap_drm_usergart_entry {
struct tiler_block *block; /* the reserved tiler block */
dma_addr_t dma_addr;
struct drm_gem_object *obj; /* the current pinned obj */
pgoff_t obj_pgoff; /* page offset of obj currently
mapped in */
};
struct omap_drm_usergart {
struct omap_drm_usergart_entry entry[NUM_USERGART_ENTRIES];
int height; /* height in rows */
int height_shift; /* ilog2(height in rows) */
int slot_shift; /* ilog2(width per slot) */
int stride_pfn; /* stride in pages */
int last; /* index of last used entry */
};
/* -----------------------------------------------------------------------------
* Helpers
*/
/** get mmap offset */
u64 omap_gem_mmap_offset(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
int ret;
size_t size;
/* Make it mmapable */
size = omap_gem_mmap_size(obj);
ret = drm_gem_create_mmap_offset_size(obj, size);
if (ret) {
dev_err(dev->dev, "could not allocate mmap offset\n");
return 0;
}
return drm_vma_node_offset_addr(&obj->vma_node);
}
static bool omap_gem_is_contiguous(struct omap_gem_object *omap_obj)
{
if (omap_obj->flags & OMAP_BO_MEM_DMA_API)
return true;
if ((omap_obj->flags & OMAP_BO_MEM_DMABUF) && omap_obj->sgt->nents == 1)
return true;
return false;
}
/* -----------------------------------------------------------------------------
* Eviction
*/
static void omap_gem_evict_entry(struct drm_gem_object *obj,
enum tiler_fmt fmt, struct omap_drm_usergart_entry *entry)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
struct omap_drm_private *priv = obj->dev->dev_private;
int n = priv->usergart[fmt].height;
size_t size = PAGE_SIZE * n;
loff_t off = omap_gem_mmap_offset(obj) +
(entry->obj_pgoff << PAGE_SHIFT);
const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE);
if (m > 1) {
int i;
/* if stride > than PAGE_SIZE then sparse mapping: */
for (i = n; i > 0; i--) {
unmap_mapping_range(obj->dev->anon_inode->i_mapping,
off, PAGE_SIZE, 1);
off += PAGE_SIZE * m;
}
} else {
unmap_mapping_range(obj->dev->anon_inode->i_mapping,
off, size, 1);
}
entry->obj = NULL;
}
/* Evict a buffer from usergart, if it is mapped there */
static void omap_gem_evict(struct drm_gem_object *obj)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
struct omap_drm_private *priv = obj->dev->dev_private;
if (omap_obj->flags & OMAP_BO_TILED_MASK) {
enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
int i;
for (i = 0; i < NUM_USERGART_ENTRIES; i++) {
struct omap_drm_usergart_entry *entry =
&priv->usergart[fmt].entry[i];
if (entry->obj == obj)
omap_gem_evict_entry(obj, fmt, entry);
}
}
}
/* -----------------------------------------------------------------------------
* Page Management
*/
/*
* Ensure backing pages are allocated. Must be called with the omap_obj.lock
* held.
*/
static int omap_gem_attach_pages(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
struct page **pages;
int npages = obj->size >> PAGE_SHIFT;
int i, ret;
dma_addr_t *addrs;
lockdep_assert_held(&omap_obj->lock);
/*
* If not using shmem (in which case backing pages don't need to be
* allocated) or if pages are already allocated we're done.
*/
if (!(omap_obj->flags & OMAP_BO_MEM_SHMEM) || omap_obj->pages)
return 0;
pages = drm_gem_get_pages(obj);
if (IS_ERR(pages)) {
dev_err(obj->dev->dev, "could not get pages: %ld\n", PTR_ERR(pages));
return PTR_ERR(pages);
}
/* for non-cached buffers, ensure the new pages are clean because
* DSS, GPU, etc. are not cache coherent:
*/
if (omap_obj->flags & (OMAP_BO_WC|OMAP_BO_UNCACHED)) {
addrs = kmalloc_array(npages, sizeof(*addrs), GFP_KERNEL);
if (!addrs) {
ret = -ENOMEM;
goto free_pages;
}
for (i = 0; i < npages; i++) {
addrs[i] = dma_map_page(dev->dev, pages[i],
0, PAGE_SIZE, DMA_TO_DEVICE);
if (dma_mapping_error(dev->dev, addrs[i])) {
dev_warn(dev->dev,
"%s: failed to map page\n", __func__);
for (i = i - 1; i >= 0; --i) {
dma_unmap_page(dev->dev, addrs[i],
PAGE_SIZE, DMA_TO_DEVICE);
}
ret = -ENOMEM;
goto free_addrs;
}
}
} else {
addrs = kcalloc(npages, sizeof(*addrs), GFP_KERNEL);
if (!addrs) {
ret = -ENOMEM;
goto free_pages;
}
}
omap_obj->dma_addrs = addrs;
omap_obj->pages = pages;
return 0;
free_addrs:
kfree(addrs);
free_pages:
drm_gem_put_pages(obj, pages, true, false);
return ret;
}
/* Release backing pages. Must be called with the omap_obj.lock held. */
static void omap_gem_detach_pages(struct drm_gem_object *obj)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
unsigned int npages = obj->size >> PAGE_SHIFT;
unsigned int i;
lockdep_assert_held(&omap_obj->lock);
for (i = 0; i < npages; i++) {
if (omap_obj->dma_addrs[i])
dma_unmap_page(obj->dev->dev, omap_obj->dma_addrs[i],
PAGE_SIZE, DMA_TO_DEVICE);
}
kfree(omap_obj->dma_addrs);
omap_obj->dma_addrs = NULL;
drm_gem_put_pages(obj, omap_obj->pages, true, false);
omap_obj->pages = NULL;
}
/* get buffer flags */
u32 omap_gem_flags(struct drm_gem_object *obj)
{
return to_omap_bo(obj)->flags;
}
/** get mmap size */
size_t omap_gem_mmap_size(struct drm_gem_object *obj)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
size_t size = obj->size;
if (omap_obj->flags & OMAP_BO_TILED_MASK) {
/* for tiled buffers, the virtual size has stride rounded up
* to 4kb.. (to hide the fact that row n+1 might start 16kb or
* 32kb later!). But we don't back the entire buffer with
* pages, only the valid picture part.. so need to adjust for
* this in the size used to mmap and generate mmap offset
*/
size = tiler_vsize(gem2fmt(omap_obj->flags),
omap_obj->width, omap_obj->height);
}
return size;
}
/* -----------------------------------------------------------------------------
* Fault Handling
*/
/* Normal handling for the case of faulting in non-tiled buffers */
static vm_fault_t omap_gem_fault_1d(struct drm_gem_object *obj,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
unsigned long pfn;
pgoff_t pgoff;
/* We don't use vmf->pgoff since that has the fake offset: */
pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
if (omap_obj->pages) {
omap_gem_cpu_sync_page(obj, pgoff);
pfn = page_to_pfn(omap_obj->pages[pgoff]);
} else {
BUG_ON(!omap_gem_is_contiguous(omap_obj));
pfn = (omap_obj->dma_addr >> PAGE_SHIFT) + pgoff;
}
VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
pfn, pfn << PAGE_SHIFT);
return vmf_insert_mixed(vma, vmf->address,
__pfn_to_pfn_t(pfn, PFN_DEV));
}
/* Special handling for the case of faulting in 2d tiled buffers */
static vm_fault_t omap_gem_fault_2d(struct drm_gem_object *obj,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
struct omap_drm_private *priv = obj->dev->dev_private;
struct omap_drm_usergart_entry *entry;
enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
struct page *pages[64]; /* XXX is this too much to have on stack? */
unsigned long pfn;
pgoff_t pgoff, base_pgoff;
unsigned long vaddr;
int i, err, slots;
vm_fault_t ret = VM_FAULT_NOPAGE;
/*
* Note the height of the slot is also equal to the number of pages
* that need to be mapped in to fill 4kb wide CPU page. If the slot
* height is 64, then 64 pages fill a 4kb wide by 64 row region.
*/
const int n = priv->usergart[fmt].height;
const int n_shift = priv->usergart[fmt].height_shift;
/*
* If buffer width in bytes > PAGE_SIZE then the virtual stride is
* rounded up to next multiple of PAGE_SIZE.. this need to be taken
* into account in some of the math, so figure out virtual stride
* in pages
*/
const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE);
/* We don't use vmf->pgoff since that has the fake offset: */
pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
/*
* Actual address we start mapping at is rounded down to previous slot
* boundary in the y direction:
*/
base_pgoff = round_down(pgoff, m << n_shift);
/* figure out buffer width in slots */
slots = omap_obj->width >> priv->usergart[fmt].slot_shift;
vaddr = vmf->address - ((pgoff - base_pgoff) << PAGE_SHIFT);
entry = &priv->usergart[fmt].entry[priv->usergart[fmt].last];
/* evict previous buffer using this usergart entry, if any: */
if (entry->obj)
omap_gem_evict_entry(entry->obj, fmt, entry);
entry->obj = obj;
entry->obj_pgoff = base_pgoff;
/* now convert base_pgoff to phys offset from virt offset: */
base_pgoff = (base_pgoff >> n_shift) * slots;
/* for wider-than 4k.. figure out which part of the slot-row we want: */
if (m > 1) {
int off = pgoff % m;
entry->obj_pgoff += off;
base_pgoff /= m;
slots = min(slots - (off << n_shift), n);
base_pgoff += off << n_shift;
vaddr += off << PAGE_SHIFT;
}
/*
* Map in pages. Beyond the valid pixel part of the buffer, we set
* pages[i] to NULL to get a dummy page mapped in.. if someone
* reads/writes it they will get random/undefined content, but at
* least it won't be corrupting whatever other random page used to
* be mapped in, or other undefined behavior.
*/
memcpy(pages, &omap_obj->pages[base_pgoff],
sizeof(struct page *) * slots);
memset(pages + slots, 0,
sizeof(struct page *) * (n - slots));
err = tiler_pin(entry->block, pages, ARRAY_SIZE(pages), 0, true);
if (err) {
ret = vmf_error(err);
dev_err(obj->dev->dev, "failed to pin: %d\n", err);
return ret;
}
pfn = entry->dma_addr >> PAGE_SHIFT;
VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
pfn, pfn << PAGE_SHIFT);
for (i = n; i > 0; i--) {
ret = vmf_insert_mixed(vma,
vaddr, __pfn_to_pfn_t(pfn, PFN_DEV));
if (ret & VM_FAULT_ERROR)
break;
pfn += priv->usergart[fmt].stride_pfn;
vaddr += PAGE_SIZE * m;
}
/* simple round-robin: */
priv->usergart[fmt].last = (priv->usergart[fmt].last + 1)
% NUM_USERGART_ENTRIES;
return ret;
}
/**
* omap_gem_fault - pagefault handler for GEM objects
* @vmf: fault detail
*
* Invoked when a fault occurs on an mmap of a GEM managed area. GEM
* does most of the work for us including the actual map/unmap calls
* but we need to do the actual page work.
*
* The VMA was set up by GEM. In doing so it also ensured that the
* vma->vm_private_data points to the GEM object that is backing this
* mapping.
*/
static vm_fault_t omap_gem_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct drm_gem_object *obj = vma->vm_private_data;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int err;
vm_fault_t ret;
/* Make sure we don't parallel update on a fault, nor move or remove
* something from beneath our feet
*/
mutex_lock(&omap_obj->lock);
/* if a shmem backed object, make sure we have pages attached now */
err = omap_gem_attach_pages(obj);
if (err) {
ret = vmf_error(err);
goto fail;
}
/* where should we do corresponding put_pages().. we are mapping
* the original page, rather than thru a GART, so we can't rely
* on eviction to trigger this. But munmap() or all mappings should
* probably trigger put_pages()?
*/
if (omap_obj->flags & OMAP_BO_TILED_MASK)
ret = omap_gem_fault_2d(obj, vma, vmf);
else
ret = omap_gem_fault_1d(obj, vma, vmf);
fail:
mutex_unlock(&omap_obj->lock);
return ret;
}
/** We override mainly to fix up some of the vm mapping flags.. */
int omap_gem_mmap(struct file *filp, struct vm_area_struct *vma)
{
int ret;
ret = drm_gem_mmap(filp, vma);
if (ret) {
DBG("mmap failed: %d", ret);
return ret;
}
return omap_gem_mmap_obj(vma->vm_private_data, vma);
}
int omap_gem_mmap_obj(struct drm_gem_object *obj,
struct vm_area_struct *vma)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
vma->vm_flags &= ~VM_PFNMAP;
vma->vm_flags |= VM_MIXEDMAP;
if (omap_obj->flags & OMAP_BO_WC) {
vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
} else if (omap_obj->flags & OMAP_BO_UNCACHED) {
vma->vm_page_prot = pgprot_noncached(vm_get_page_prot(vma->vm_flags));
} else {
/*
* We do have some private objects, at least for scanout buffers
* on hardware without DMM/TILER. But these are allocated write-
* combine
*/
if (WARN_ON(!obj->filp))
return -EINVAL;
/*
* Shunt off cached objs to shmem file so they have their own
* address_space (so unmap_mapping_range does what we want,
* in particular in the case of mmap'd dmabufs)
*/
vma->vm_pgoff = 0;
vma_set_file(vma, obj->filp);
vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
}
return 0;
}
/* -----------------------------------------------------------------------------
* Dumb Buffers
*/
/**
* omap_gem_dumb_create - create a dumb buffer
* @file: our client file
* @dev: our device
* @args: the requested arguments copied from userspace
*
* Allocate a buffer suitable for use for a frame buffer of the
* form described by user space. Give userspace a handle by which
* to reference it.
*/
int omap_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
struct drm_mode_create_dumb *args)
{
union omap_gem_size gsize;
args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
args->size = PAGE_ALIGN(args->pitch * args->height);
gsize = (union omap_gem_size){
.bytes = args->size,
};
return omap_gem_new_handle(dev, file, gsize,
OMAP_BO_SCANOUT | OMAP_BO_WC, &args->handle);
}
/**
* omap_gem_dumb_map - buffer mapping for dumb interface
* @file: our drm client file
* @dev: drm device
* @handle: GEM handle to the object (from dumb_create)
* @offset: memory map offset placeholder
*
* Do the necessary setup to allow the mapping of the frame buffer
* into user memory. We don't have to do much here at the moment.
*/
int omap_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
u32 handle, u64 *offset)
{
struct drm_gem_object *obj;
int ret = 0;
/* GEM does all our handle to object mapping */
obj = drm_gem_object_lookup(file, handle);
if (obj == NULL) {
ret = -ENOENT;
goto fail;
}
*offset = omap_gem_mmap_offset(obj);
drm_gem_object_put(obj);
fail:
return ret;
}
#ifdef CONFIG_DRM_FBDEV_EMULATION
/* Set scrolling position. This allows us to implement fast scrolling
* for console.
*
* Call only from non-atomic contexts.
*/
int omap_gem_roll(struct drm_gem_object *obj, u32 roll)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
u32 npages = obj->size >> PAGE_SHIFT;
int ret = 0;
if (roll > npages) {
dev_err(obj->dev->dev, "invalid roll: %d\n", roll);
return -EINVAL;
}
omap_obj->roll = roll;
mutex_lock(&omap_obj->lock);
/* if we aren't mapped yet, we don't need to do anything */
if (omap_obj->block) {
ret = omap_gem_attach_pages(obj);
if (ret)
goto fail;
ret = tiler_pin(omap_obj->block, omap_obj->pages, npages,
roll, true);
if (ret)
dev_err(obj->dev->dev, "could not repin: %d\n", ret);
}
fail:
mutex_unlock(&omap_obj->lock);
return ret;
}
#endif
/* -----------------------------------------------------------------------------
* Memory Management & DMA Sync
*/
/*
* shmem buffers that are mapped cached are not coherent.
*
* We keep track of dirty pages using page faulting to perform cache management.
* When a page is mapped to the CPU in read/write mode the device can't access
* it and omap_obj->dma_addrs[i] is NULL. When a page is mapped to the device
* the omap_obj->dma_addrs[i] is set to the DMA address, and the page is
* unmapped from the CPU.
*/
static inline bool omap_gem_is_cached_coherent(struct drm_gem_object *obj)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
return !((omap_obj->flags & OMAP_BO_MEM_SHMEM) &&
((omap_obj->flags & OMAP_BO_CACHE_MASK) == OMAP_BO_CACHED));
}
/* Sync the buffer for CPU access.. note pages should already be
* attached, ie. omap_gem_get_pages()
*/
void omap_gem_cpu_sync_page(struct drm_gem_object *obj, int pgoff)
{
struct drm_device *dev = obj->dev;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
if (omap_gem_is_cached_coherent(obj))
return;
if (omap_obj->dma_addrs[pgoff]) {
dma_unmap_page(dev->dev, omap_obj->dma_addrs[pgoff],
PAGE_SIZE, DMA_TO_DEVICE);
omap_obj->dma_addrs[pgoff] = 0;
}
}
/* sync the buffer for DMA access */
void omap_gem_dma_sync_buffer(struct drm_gem_object *obj,
enum dma_data_direction dir)
{
struct drm_device *dev = obj->dev;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int i, npages = obj->size >> PAGE_SHIFT;
struct page **pages = omap_obj->pages;
bool dirty = false;
if (omap_gem_is_cached_coherent(obj))
return;
for (i = 0; i < npages; i++) {
if (!omap_obj->dma_addrs[i]) {
dma_addr_t addr;
addr = dma_map_page(dev->dev, pages[i], 0,
PAGE_SIZE, dir);
if (dma_mapping_error(dev->dev, addr)) {
dev_warn(dev->dev, "%s: failed to map page\n",
__func__);
break;
}
dirty = true;
omap_obj->dma_addrs[i] = addr;
}
}
if (dirty) {
unmap_mapping_range(obj->filp->f_mapping, 0,
omap_gem_mmap_size(obj), 1);
}
}
/**
* omap_gem_pin() - Pin a GEM object in memory
* @obj: the GEM object
* @dma_addr: the DMA address
*
* Pin the given GEM object in memory and fill the dma_addr pointer with the
* object's DMA address. If the buffer is not physically contiguous it will be
* remapped through the TILER to provide a contiguous view.
*
* Pins are reference-counted, calling this function multiple times is allowed
* as long the corresponding omap_gem_unpin() calls are balanced.
*
* Return 0 on success or a negative error code otherwise.
*/
int omap_gem_pin(struct drm_gem_object *obj, dma_addr_t *dma_addr)
{
struct omap_drm_private *priv = obj->dev->dev_private;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int ret = 0;
mutex_lock(&omap_obj->lock);
if (!omap_gem_is_contiguous(omap_obj) && priv->has_dmm) {
if (refcount_read(&omap_obj->dma_addr_cnt) == 0) {
u32 npages = obj->size >> PAGE_SHIFT;
enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
struct tiler_block *block;
BUG_ON(omap_obj->block);
refcount_set(&omap_obj->dma_addr_cnt, 1);
ret = omap_gem_attach_pages(obj);
if (ret)
goto fail;
if (omap_obj->flags & OMAP_BO_TILED_MASK) {
block = tiler_reserve_2d(fmt,
omap_obj->width,
omap_obj->height, 0);
} else {
block = tiler_reserve_1d(obj->size);
}
if (IS_ERR(block)) {
ret = PTR_ERR(block);
dev_err(obj->dev->dev,
"could not remap: %d (%d)\n", ret, fmt);
goto fail;
}
/* TODO: enable async refill.. */
ret = tiler_pin(block, omap_obj->pages, npages,
omap_obj->roll, true);
if (ret) {
tiler_release(block);
dev_err(obj->dev->dev,
"could not pin: %d\n", ret);
goto fail;
}
omap_obj->dma_addr = tiler_ssptr(block);
omap_obj->block = block;
DBG("got dma address: %pad", &omap_obj->dma_addr);
} else {
refcount_inc(&omap_obj->dma_addr_cnt);
}
if (dma_addr)
*dma_addr = omap_obj->dma_addr;
} else if (omap_gem_is_contiguous(omap_obj)) {
if (dma_addr)
*dma_addr = omap_obj->dma_addr;
} else {
ret = -EINVAL;
goto fail;
}
fail:
mutex_unlock(&omap_obj->lock);
return ret;
}
/**
* omap_gem_unpin_locked() - Unpin a GEM object from memory
* @obj: the GEM object
*
* omap_gem_unpin() without locking.
*/
static void omap_gem_unpin_locked(struct drm_gem_object *obj)
{
struct omap_drm_private *priv = obj->dev->dev_private;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int ret;
if (omap_gem_is_contiguous(omap_obj) || !priv->has_dmm)
return;
if (refcount_dec_and_test(&omap_obj->dma_addr_cnt)) {
ret = tiler_unpin(omap_obj->block);
if (ret) {
dev_err(obj->dev->dev,
"could not unpin pages: %d\n", ret);
}
ret = tiler_release(omap_obj->block);
if (ret) {
dev_err(obj->dev->dev,
"could not release unmap: %d\n", ret);
}
omap_obj->dma_addr = 0;
omap_obj->block = NULL;
}
}
/**
* omap_gem_unpin() - Unpin a GEM object from memory
* @obj: the GEM object
*
* Unpin the given GEM object previously pinned with omap_gem_pin(). Pins are
* reference-counted, the actual unpin will only be performed when the number
* of calls to this function matches the number of calls to omap_gem_pin().
*/
void omap_gem_unpin(struct drm_gem_object *obj)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
mutex_lock(&omap_obj->lock);
omap_gem_unpin_locked(obj);
mutex_unlock(&omap_obj->lock);
}
/* Get rotated scanout address (only valid if already pinned), at the
* specified orientation and x,y offset from top-left corner of buffer
* (only valid for tiled 2d buffers)
*/
int omap_gem_rotated_dma_addr(struct drm_gem_object *obj, u32 orient,
int x, int y, dma_addr_t *dma_addr)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int ret = -EINVAL;
mutex_lock(&omap_obj->lock);
if ((refcount_read(&omap_obj->dma_addr_cnt) > 0) && omap_obj->block &&
(omap_obj->flags & OMAP_BO_TILED_MASK)) {
*dma_addr = tiler_tsptr(omap_obj->block, orient, x, y);
ret = 0;
}
mutex_unlock(&omap_obj->lock);
return ret;
}
/* Get tiler stride for the buffer (only valid for 2d tiled buffers) */
int omap_gem_tiled_stride(struct drm_gem_object *obj, u32 orient)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int ret = -EINVAL;
if (omap_obj->flags & OMAP_BO_TILED_MASK)
ret = tiler_stride(gem2fmt(omap_obj->flags), orient);
return ret;
}
/* if !remap, and we don't have pages backing, then fail, rather than
* increasing the pin count (which we don't really do yet anyways,
* because we don't support swapping pages back out). And 'remap'
* might not be quite the right name, but I wanted to keep it working
* similarly to omap_gem_pin(). Note though that mutex is not
* aquired if !remap (because this can be called in atomic ctxt),
* but probably omap_gem_unpin() should be changed to work in the
* same way. If !remap, a matching omap_gem_put_pages() call is not
* required (and should not be made).
*/
int omap_gem_get_pages(struct drm_gem_object *obj, struct page ***pages,
bool remap)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int ret = 0;
mutex_lock(&omap_obj->lock);
if (remap) {
ret = omap_gem_attach_pages(obj);
if (ret)
goto unlock;
}
if (!omap_obj->pages) {
ret = -ENOMEM;
goto unlock;
}
*pages = omap_obj->pages;
unlock:
mutex_unlock(&omap_obj->lock);
return ret;
}
/* release pages when DMA no longer being performed */
int omap_gem_put_pages(struct drm_gem_object *obj)
{
/* do something here if we dynamically attach/detach pages.. at
* least they would no longer need to be pinned if everyone has
* released the pages..
*/
return 0;
}
#ifdef CONFIG_DRM_FBDEV_EMULATION
/*
* Get kernel virtual address for CPU access.. this more or less only
* exists for omap_fbdev.
*/
void *omap_gem_vaddr(struct drm_gem_object *obj)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
void *vaddr;
int ret;
mutex_lock(&omap_obj->lock);
if (!omap_obj->vaddr) {
ret = omap_gem_attach_pages(obj);
if (ret) {
vaddr = ERR_PTR(ret);
goto unlock;
}
omap_obj->vaddr = vmap(omap_obj->pages, obj->size >> PAGE_SHIFT,
VM_MAP, pgprot_writecombine(PAGE_KERNEL));
}
vaddr = omap_obj->vaddr;
unlock:
mutex_unlock(&omap_obj->lock);
return vaddr;
}
#endif
/* -----------------------------------------------------------------------------
* Power Management
*/
#ifdef CONFIG_PM
/* re-pin objects in DMM in resume path: */
int omap_gem_resume(struct drm_device *dev)
{
struct omap_drm_private *priv = dev->dev_private;
struct omap_gem_object *omap_obj;
int ret = 0;
mutex_lock(&priv->list_lock);
list_for_each_entry(omap_obj, &priv->obj_list, mm_list) {
if (omap_obj->block) {
struct drm_gem_object *obj = &omap_obj->base;
u32 npages = obj->size >> PAGE_SHIFT;
WARN_ON(!omap_obj->pages); /* this can't happen */
ret = tiler_pin(omap_obj->block,
omap_obj->pages, npages,
omap_obj->roll, true);
if (ret) {
dev_err(dev->dev, "could not repin: %d\n", ret);
goto done;
}
}
}
done:
mutex_unlock(&priv->list_lock);
return ret;
}
#endif
/* -----------------------------------------------------------------------------
* DebugFS
*/
#ifdef CONFIG_DEBUG_FS
void omap_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
{
struct omap_gem_object *omap_obj = to_omap_bo(obj);
u64 off;
off = drm_vma_node_start(&obj->vma_node);
mutex_lock(&omap_obj->lock);
seq_printf(m, "%08x: %2d (%2d) %08llx %pad (%2d) %p %4d",
omap_obj->flags, obj->name, kref_read(&obj->refcount),
off, &omap_obj->dma_addr,
refcount_read(&omap_obj->dma_addr_cnt),
omap_obj->vaddr, omap_obj->roll);
if (omap_obj->flags & OMAP_BO_TILED_MASK) {
seq_printf(m, " %dx%d", omap_obj->width, omap_obj->height);
if (omap_obj->block) {
struct tcm_area *area = &omap_obj->block->area;
seq_printf(m, " (%dx%d, %dx%d)",
area->p0.x, area->p0.y,
area->p1.x, area->p1.y);
}
} else {
seq_printf(m, " %zu", obj->size);
}
mutex_unlock(&omap_obj->lock);
seq_printf(m, "\n");
}
void omap_gem_describe_objects(struct list_head *list, struct seq_file *m)
{
struct omap_gem_object *omap_obj;
int count = 0;
size_t size = 0;
list_for_each_entry(omap_obj, list, mm_list) {
struct drm_gem_object *obj = &omap_obj->base;
seq_printf(m, " ");
omap_gem_describe(obj, m);
count++;
size += obj->size;
}
seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
}
#endif
/* -----------------------------------------------------------------------------
* Constructor & Destructor
*/
static void omap_gem_free_object(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
struct omap_drm_private *priv = dev->dev_private;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
omap_gem_evict(obj);
mutex_lock(&priv->list_lock);
list_del(&omap_obj->mm_list);
mutex_unlock(&priv->list_lock);
/*
* We own the sole reference to the object at this point, but to keep
* lockdep happy, we must still take the omap_obj_lock to call
* omap_gem_detach_pages(). This should hardly make any difference as
* there can't be any lock contention.
*/
mutex_lock(&omap_obj->lock);
/* The object should not be pinned. */
WARN_ON(refcount_read(&omap_obj->dma_addr_cnt) > 0);
if (omap_obj->pages) {
if (omap_obj->flags & OMAP_BO_MEM_DMABUF)
kfree(omap_obj->pages);
else
omap_gem_detach_pages(obj);
}
if (omap_obj->flags & OMAP_BO_MEM_DMA_API) {
dma_free_wc(dev->dev, obj->size, omap_obj->vaddr,
omap_obj->dma_addr);
} else if (omap_obj->vaddr) {
vunmap(omap_obj->vaddr);
} else if (obj->import_attach) {
drm_prime_gem_destroy(obj, omap_obj->sgt);
}
mutex_unlock(&omap_obj->lock);
drm_gem_object_release(obj);
mutex_destroy(&omap_obj->lock);
kfree(omap_obj);
}
static bool omap_gem_validate_flags(struct drm_device *dev, u32 flags)
{
struct omap_drm_private *priv = dev->dev_private;
switch (flags & OMAP_BO_CACHE_MASK) {
case OMAP_BO_CACHED:
case OMAP_BO_WC:
case OMAP_BO_CACHE_MASK:
break;
default:
return false;
}
if (flags & OMAP_BO_TILED_MASK) {
if (!priv->usergart)
return false;
switch (flags & OMAP_BO_TILED_MASK) {
case OMAP_BO_TILED_8:
case OMAP_BO_TILED_16:
case OMAP_BO_TILED_32:
break;
default:
return false;
}
}
return true;
}
static const struct vm_operations_struct omap_gem_vm_ops = {
.fault = omap_gem_fault,
.open = drm_gem_vm_open,
.close = drm_gem_vm_close,
};
static const struct drm_gem_object_funcs omap_gem_object_funcs = {
.free = omap_gem_free_object,
.export = omap_gem_prime_export,
.vm_ops = &omap_gem_vm_ops,
};
/* GEM buffer object constructor */
struct drm_gem_object *omap_gem_new(struct drm_device *dev,
union omap_gem_size gsize, u32 flags)
{
struct omap_drm_private *priv = dev->dev_private;
struct omap_gem_object *omap_obj;
struct drm_gem_object *obj;
struct address_space *mapping;
size_t size;
int ret;
if (!omap_gem_validate_flags(dev, flags))
return NULL;
/* Validate the flags and compute the memory and cache flags. */
if (flags & OMAP_BO_TILED_MASK) {
/*
* Tiled buffers are always shmem paged backed. When they are
* scanned out, they are remapped into DMM/TILER.
*/
flags |= OMAP_BO_MEM_SHMEM;
/*
* Currently don't allow cached buffers. There is some caching
* stuff that needs to be handled better.
*/
flags &= ~(OMAP_BO_CACHED|OMAP_BO_WC|OMAP_BO_UNCACHED);
flags |= tiler_get_cpu_cache_flags();
} else if ((flags & OMAP_BO_SCANOUT) && !priv->has_dmm) {
/*
* If we don't have DMM, we must allocate scanout buffers
* from contiguous DMA memory.
*/
flags |= OMAP_BO_MEM_DMA_API;
} else if (!(flags & OMAP_BO_MEM_DMABUF)) {
/*
* All other buffers not backed by dma_buf are shmem-backed.
*/
flags |= OMAP_BO_MEM_SHMEM;
}
/* Allocate the initialize the OMAP GEM object. */
omap_obj = kzalloc(sizeof(*omap_obj), GFP_KERNEL);
if (!omap_obj)
return NULL;
obj = &omap_obj->base;
omap_obj->flags = flags;
mutex_init(&omap_obj->lock);
if (flags & OMAP_BO_TILED_MASK) {
/*
* For tiled buffers align dimensions to slot boundaries and
* calculate size based on aligned dimensions.
*/
tiler_align(gem2fmt(flags), &gsize.tiled.width,
&gsize.tiled.height);
size = tiler_size(gem2fmt(flags), gsize.tiled.width,
gsize.tiled.height);
omap_obj->width = gsize.tiled.width;
omap_obj->height = gsize.tiled.height;
} else {
size = PAGE_ALIGN(gsize.bytes);
}
obj->funcs = &omap_gem_object_funcs;
/* Initialize the GEM object. */
if (!(flags & OMAP_BO_MEM_SHMEM)) {
drm_gem_private_object_init(dev, obj, size);
} else {
ret = drm_gem_object_init(dev, obj, size);
if (ret)
goto err_free;
mapping = obj->filp->f_mapping;
mapping_set_gfp_mask(mapping, GFP_USER | __GFP_DMA32);
}
/* Allocate memory if needed. */
if (flags & OMAP_BO_MEM_DMA_API) {
omap_obj->vaddr = dma_alloc_wc(dev->dev, size,
&omap_obj->dma_addr,
GFP_KERNEL);
if (!omap_obj->vaddr)
goto err_release;
}
mutex_lock(&priv->list_lock);
list_add(&omap_obj->mm_list, &priv->obj_list);
mutex_unlock(&priv->list_lock);
return obj;
err_release:
drm_gem_object_release(obj);
err_free:
kfree(omap_obj);
return NULL;
}
struct drm_gem_object *omap_gem_new_dmabuf(struct drm_device *dev, size_t size,
struct sg_table *sgt)
{
struct omap_drm_private *priv = dev->dev_private;
struct omap_gem_object *omap_obj;
struct drm_gem_object *obj;
union omap_gem_size gsize;
/* Without a DMM only physically contiguous buffers can be supported. */
if (sgt->orig_nents != 1 && !priv->has_dmm)
return ERR_PTR(-EINVAL);
gsize.bytes = PAGE_ALIGN(size);
obj = omap_gem_new(dev, gsize, OMAP_BO_MEM_DMABUF | OMAP_BO_WC);
if (!obj)
return ERR_PTR(-ENOMEM);
omap_obj = to_omap_bo(obj);
mutex_lock(&omap_obj->lock);
omap_obj->sgt = sgt;
if (sgt->orig_nents == 1) {
omap_obj->dma_addr = sg_dma_address(sgt->sgl);
} else {
/* Create pages list from sgt */
struct page **pages;
unsigned int npages;
unsigned int ret;
npages = DIV_ROUND_UP(size, PAGE_SIZE);
pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
if (!pages) {
omap_gem_free_object(obj);
obj = ERR_PTR(-ENOMEM);
goto done;
}
omap_obj->pages = pages;
ret = drm_prime_sg_to_page_array(sgt, pages, npages);
if (ret) {
omap_gem_free_object(obj);
obj = ERR_PTR(-ENOMEM);
goto done;
}
}
done:
mutex_unlock(&omap_obj->lock);
return obj;
}
/* convenience method to construct a GEM buffer object, and userspace handle */
int omap_gem_new_handle(struct drm_device *dev, struct drm_file *file,
union omap_gem_size gsize, u32 flags, u32 *handle)
{
struct drm_gem_object *obj;
int ret;
obj = omap_gem_new(dev, gsize, flags);
if (!obj)
return -ENOMEM;
ret = drm_gem_handle_create(file, obj, handle);
if (ret) {
omap_gem_free_object(obj);
return ret;
}
/* drop reference from allocate - handle holds it now */
drm_gem_object_put(obj);
return 0;
}
/* -----------------------------------------------------------------------------
* Init & Cleanup
*/
/* If DMM is used, we need to set some stuff up.. */
void omap_gem_init(struct drm_device *dev)
{
struct omap_drm_private *priv = dev->dev_private;
struct omap_drm_usergart *usergart;
const enum tiler_fmt fmts[] = {
TILFMT_8BIT, TILFMT_16BIT, TILFMT_32BIT
};
int i, j;
if (!dmm_is_available()) {
/* DMM only supported on OMAP4 and later, so this isn't fatal */
dev_warn(dev->dev, "DMM not available, disable DMM support\n");
return;
}
usergart = kcalloc(3, sizeof(*usergart), GFP_KERNEL);
if (!usergart)
return;
/* reserve 4k aligned/wide regions for userspace mappings: */
for (i = 0; i < ARRAY_SIZE(fmts); i++) {
u16 h = 1, w = PAGE_SIZE >> i;
tiler_align(fmts[i], &w, &h);
/* note: since each region is 1 4kb page wide, and minimum
* number of rows, the height ends up being the same as the
* # of pages in the region
*/
usergart[i].height = h;
usergart[i].height_shift = ilog2(h);
usergart[i].stride_pfn = tiler_stride(fmts[i], 0) >> PAGE_SHIFT;
usergart[i].slot_shift = ilog2((PAGE_SIZE / h) >> i);
for (j = 0; j < NUM_USERGART_ENTRIES; j++) {
struct omap_drm_usergart_entry *entry;
struct tiler_block *block;
entry = &usergart[i].entry[j];
block = tiler_reserve_2d(fmts[i], w, h, PAGE_SIZE);
if (IS_ERR(block)) {
dev_err(dev->dev,
"reserve failed: %d, %d, %ld\n",
i, j, PTR_ERR(block));
return;
}
entry->dma_addr = tiler_ssptr(block);
entry->block = block;
DBG("%d:%d: %dx%d: dma_addr=%pad stride=%d", i, j, w, h,
&entry->dma_addr,
usergart[i].stride_pfn << PAGE_SHIFT);
}
}
priv->usergart = usergart;
priv->has_dmm = true;
}
void omap_gem_deinit(struct drm_device *dev)
{
struct omap_drm_private *priv = dev->dev_private;
/* I believe we can rely on there being no more outstanding GEM
* objects which could depend on usergart/dmm at this point.
*/
kfree(priv->usergart);
}