Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 772 insertions, 0 deletions

diff --git a/drivers/gpu/drm/gma500/mmu.c b/drivers/gpu/drm/gma500/mmu.c
new file mode 100644
index 0000000000..a70b01ccdf
--- /dev/null
+++ b/drivers/gpu/drm/gma500/mmu.c
@@ -0,0 +1,772 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/**************************************************************************
+ * Copyright (c) 2007, Intel Corporation.
+ *
+ **************************************************************************/
+
+#include <linux/highmem.h>
+
+#include "mmu.h"
+#include "psb_drv.h"
+#include "psb_reg.h"
+
+/*
+ * Code for the SGX MMU:
+ */
+
+/*
+ * clflush on one processor only:
+ * clflush should apparently flush the cache line on all processors in an
+ * SMP system.
+ */
+
+/*
+ * kmap atomic:
+ * The usage of the slots must be completely encapsulated within a spinlock, and
+ * no other functions that may be using the locks for other purposed may be
+ * called from within the locked region.
+ * Since the slots are per processor, this will guarantee that we are the only
+ * user.
+ */
+
+/*
+ * TODO: Inserting ptes from an interrupt handler:
+ * This may be desirable for some SGX functionality where the GPU can fault in
+ * needed pages. For that, we need to make an atomic insert_pages function, that
+ * may fail.
+ * If it fails, the caller need to insert the page using a workqueue function,
+ * but on average it should be fast.
+ */
+
+static inline uint32_t psb_mmu_pt_index(uint32_t offset)
+{
+	return (offset >> PSB_PTE_SHIFT) & 0x3FF;
+}
+
+static inline uint32_t psb_mmu_pd_index(uint32_t offset)
+{
+	return offset >> PSB_PDE_SHIFT;
+}
+
+static inline void psb_clflush(void *addr)
+{
+	__asm__ __volatile__("clflush (%0)\n" : : "r"(addr) : "memory");
+}
+
+static inline void psb_mmu_clflush(struct psb_mmu_driver *driver, void *addr)
+{
+	if (!driver->has_clflush)
+		return;
+
+	mb();
+	psb_clflush(addr);
+	mb();
+}
+
+static void psb_mmu_flush_pd_locked(struct psb_mmu_driver *driver, int force)
+{
+	struct drm_device *dev = driver->dev;
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+
+	if (atomic_read(&driver->needs_tlbflush) || force) {
+		uint32_t val = PSB_RSGX32(PSB_CR_BIF_CTRL);
+		PSB_WSGX32(val | _PSB_CB_CTRL_INVALDC, PSB_CR_BIF_CTRL);
+
+		/* Make sure data cache is turned off before enabling it */
+		wmb();
+		PSB_WSGX32(val & ~_PSB_CB_CTRL_INVALDC, PSB_CR_BIF_CTRL);
+		(void)PSB_RSGX32(PSB_CR_BIF_CTRL);
+		if (driver->msvdx_mmu_invaldc)
+			atomic_set(driver->msvdx_mmu_invaldc, 1);
+	}
+	atomic_set(&driver->needs_tlbflush, 0);
+}
+
+#if 0
+static void psb_mmu_flush_pd(struct psb_mmu_driver *driver, int force)
+{
+	down_write(&driver->sem);
+	psb_mmu_flush_pd_locked(driver, force);
+	up_write(&driver->sem);
+}
+#endif
+
+void psb_mmu_flush(struct psb_mmu_driver *driver)
+{
+	struct drm_device *dev = driver->dev;
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+	uint32_t val;
+
+	down_write(&driver->sem);
+	val = PSB_RSGX32(PSB_CR_BIF_CTRL);
+	if (atomic_read(&driver->needs_tlbflush))
+		PSB_WSGX32(val | _PSB_CB_CTRL_INVALDC, PSB_CR_BIF_CTRL);
+	else
+		PSB_WSGX32(val | _PSB_CB_CTRL_FLUSH, PSB_CR_BIF_CTRL);
+
+	/* Make sure data cache is turned off and MMU is flushed before
+	   restoring bank interface control register */
+	wmb();
+	PSB_WSGX32(val & ~(_PSB_CB_CTRL_FLUSH | _PSB_CB_CTRL_INVALDC),
+		   PSB_CR_BIF_CTRL);
+	(void)PSB_RSGX32(PSB_CR_BIF_CTRL);
+
+	atomic_set(&driver->needs_tlbflush, 0);
+	if (driver->msvdx_mmu_invaldc)
+		atomic_set(driver->msvdx_mmu_invaldc, 1);
+	up_write(&driver->sem);
+}
+
+void psb_mmu_set_pd_context(struct psb_mmu_pd *pd, int hw_context)
+{
+	struct drm_device *dev = pd->driver->dev;
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+	uint32_t offset = (hw_context == 0) ? PSB_CR_BIF_DIR_LIST_BASE0 :
+			  PSB_CR_BIF_DIR_LIST_BASE1 + hw_context * 4;
+
+	down_write(&pd->driver->sem);
+	PSB_WSGX32(page_to_pfn(pd->p) << PAGE_SHIFT, offset);
+	wmb();
+	psb_mmu_flush_pd_locked(pd->driver, 1);
+	pd->hw_context = hw_context;
+	up_write(&pd->driver->sem);
+
+}
+
+static inline unsigned long psb_pd_addr_end(unsigned long addr,
+					    unsigned long end)
+{
+	addr = (addr + PSB_PDE_MASK + 1) & ~PSB_PDE_MASK;
+	return (addr < end) ? addr : end;
+}
+
+static inline uint32_t psb_mmu_mask_pte(uint32_t pfn, int type)
+{
+	uint32_t mask = PSB_PTE_VALID;
+
+	if (type & PSB_MMU_CACHED_MEMORY)
+		mask |= PSB_PTE_CACHED;
+	if (type & PSB_MMU_RO_MEMORY)
+		mask |= PSB_PTE_RO;
+	if (type & PSB_MMU_WO_MEMORY)
+		mask |= PSB_PTE_WO;
+
+	return (pfn << PAGE_SHIFT) | mask;
+}
+
+struct psb_mmu_pd *psb_mmu_alloc_pd(struct psb_mmu_driver *driver,
+				    int trap_pagefaults, int invalid_type)
+{
+	struct psb_mmu_pd *pd = kmalloc(sizeof(*pd), GFP_KERNEL);
+	uint32_t *v;
+	int i;
+
+	if (!pd)
+		return NULL;
+
+	pd->p = alloc_page(GFP_DMA32);
+	if (!pd->p)
+		goto out_err1;
+	pd->dummy_pt = alloc_page(GFP_DMA32);
+	if (!pd->dummy_pt)
+		goto out_err2;
+	pd->dummy_page = alloc_page(GFP_DMA32);
+	if (!pd->dummy_page)
+		goto out_err3;
+
+	if (!trap_pagefaults) {
+		pd->invalid_pde = psb_mmu_mask_pte(page_to_pfn(pd->dummy_pt),
+						   invalid_type);
+		pd->invalid_pte = psb_mmu_mask_pte(page_to_pfn(pd->dummy_page),
+						   invalid_type);
+	} else {
+		pd->invalid_pde = 0;
+		pd->invalid_pte = 0;
+	}
+
+	v = kmap_local_page(pd->dummy_pt);
+	for (i = 0; i < (PAGE_SIZE / sizeof(uint32_t)); ++i)
+		v[i] = pd->invalid_pte;
+
+	kunmap_local(v);
+
+	v = kmap_local_page(pd->p);
+	for (i = 0; i < (PAGE_SIZE / sizeof(uint32_t)); ++i)
+		v[i] = pd->invalid_pde;
+
+	kunmap_local(v);
+
+	clear_page(kmap(pd->dummy_page));
+	kunmap(pd->dummy_page);
+
+	pd->tables = vmalloc_user(sizeof(struct psb_mmu_pt *) * 1024);
+	if (!pd->tables)
+		goto out_err4;
+
+	pd->hw_context = -1;
+	pd->pd_mask = PSB_PTE_VALID;
+	pd->driver = driver;
+
+	return pd;
+
+out_err4:
+	__free_page(pd->dummy_page);
+out_err3:
+	__free_page(pd->dummy_pt);
+out_err2:
+	__free_page(pd->p);
+out_err1:
+	kfree(pd);
+	return NULL;
+}
+
+static void psb_mmu_free_pt(struct psb_mmu_pt *pt)
+{
+	__free_page(pt->p);
+	kfree(pt);
+}
+
+void psb_mmu_free_pagedir(struct psb_mmu_pd *pd)
+{
+	struct psb_mmu_driver *driver = pd->driver;
+	struct drm_device *dev = driver->dev;
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+	struct psb_mmu_pt *pt;
+	int i;
+
+	down_write(&driver->sem);
+	if (pd->hw_context != -1) {
+		PSB_WSGX32(0, PSB_CR_BIF_DIR_LIST_BASE0 + pd->hw_context * 4);
+		psb_mmu_flush_pd_locked(driver, 1);
+	}
+
+	/* Should take the spinlock here, but we don't need to do that
+	   since we have the semaphore in write mode. */
+
+	for (i = 0; i < 1024; ++i) {
+		pt = pd->tables[i];
+		if (pt)
+			psb_mmu_free_pt(pt);
+	}
+
+	vfree(pd->tables);
+	__free_page(pd->dummy_page);
+	__free_page(pd->dummy_pt);
+	__free_page(pd->p);
+	kfree(pd);
+	up_write(&driver->sem);
+}
+
+static struct psb_mmu_pt *psb_mmu_alloc_pt(struct psb_mmu_pd *pd)
+{
+	struct psb_mmu_pt *pt = kmalloc(sizeof(*pt), GFP_KERNEL);
+	void *v;
+	uint32_t clflush_add = pd->driver->clflush_add >> PAGE_SHIFT;
+	uint32_t clflush_count = PAGE_SIZE / clflush_add;
+	spinlock_t *lock = &pd->driver->lock;
+	uint8_t *clf;
+	uint32_t *ptes;
+	int i;
+
+	if (!pt)
+		return NULL;
+
+	pt->p = alloc_page(GFP_DMA32);
+	if (!pt->p) {
+		kfree(pt);
+		return NULL;
+	}
+
+	spin_lock(lock);
+
+	v = kmap_atomic(pt->p);
+	clf = (uint8_t *) v;
+	ptes = (uint32_t *) v;
+	for (i = 0; i < (PAGE_SIZE / sizeof(uint32_t)); ++i)
+		*ptes++ = pd->invalid_pte;
+
+	if (pd->driver->has_clflush && pd->hw_context != -1) {
+		mb();
+		for (i = 0; i < clflush_count; ++i) {
+			psb_clflush(clf);
+			clf += clflush_add;
+		}
+		mb();
+	}
+	kunmap_atomic(v);
+	spin_unlock(lock);
+
+	pt->count = 0;
+	pt->pd = pd;
+	pt->index = 0;
+
+	return pt;
+}
+
+static struct psb_mmu_pt *psb_mmu_pt_alloc_map_lock(struct psb_mmu_pd *pd,
+						    unsigned long addr)
+{
+	uint32_t index = psb_mmu_pd_index(addr);
+	struct psb_mmu_pt *pt;
+	uint32_t *v;
+	spinlock_t *lock = &pd->driver->lock;
+
+	spin_lock(lock);
+	pt = pd->tables[index];
+	while (!pt) {
+		spin_unlock(lock);
+		pt = psb_mmu_alloc_pt(pd);
+		if (!pt)
+			return NULL;
+		spin_lock(lock);
+
+		if (pd->tables[index]) {
+			spin_unlock(lock);
+			psb_mmu_free_pt(pt);
+			spin_lock(lock);
+			pt = pd->tables[index];
+			continue;
+		}
+
+		v = kmap_atomic(pd->p);
+		pd->tables[index] = pt;
+		v[index] = (page_to_pfn(pt->p) << 12) | pd->pd_mask;
+		pt->index = index;
+		kunmap_atomic((void *) v);
+
+		if (pd->hw_context != -1) {
+			psb_mmu_clflush(pd->driver, (void *)&v[index]);
+			atomic_set(&pd->driver->needs_tlbflush, 1);
+		}
+	}
+	pt->v = kmap_atomic(pt->p);
+	return pt;
+}
+
+static struct psb_mmu_pt *psb_mmu_pt_map_lock(struct psb_mmu_pd *pd,
+					      unsigned long addr)
+{
+	uint32_t index = psb_mmu_pd_index(addr);
+	struct psb_mmu_pt *pt;
+	spinlock_t *lock = &pd->driver->lock;
+
+	spin_lock(lock);
+	pt = pd->tables[index];
+	if (!pt) {
+		spin_unlock(lock);
+		return NULL;
+	}
+	pt->v = kmap_atomic(pt->p);
+	return pt;
+}
+
+static void psb_mmu_pt_unmap_unlock(struct psb_mmu_pt *pt)
+{
+	struct psb_mmu_pd *pd = pt->pd;
+	uint32_t *v;
+
+	kunmap_atomic(pt->v);
+	if (pt->count == 0) {
+		v = kmap_atomic(pd->p);
+		v[pt->index] = pd->invalid_pde;
+		pd->tables[pt->index] = NULL;
+
+		if (pd->hw_context != -1) {
+			psb_mmu_clflush(pd->driver, (void *)&v[pt->index]);
+			atomic_set(&pd->driver->needs_tlbflush, 1);
+		}
+		kunmap_atomic(v);
+		spin_unlock(&pd->driver->lock);
+		psb_mmu_free_pt(pt);
+		return;
+	}
+	spin_unlock(&pd->driver->lock);
+}
+
+static inline void psb_mmu_set_pte(struct psb_mmu_pt *pt, unsigned long addr,
+				   uint32_t pte)
+{
+	pt->v[psb_mmu_pt_index(addr)] = pte;
+}
+
+static inline void psb_mmu_invalidate_pte(struct psb_mmu_pt *pt,
+					  unsigned long addr)
+{
+	pt->v[psb_mmu_pt_index(addr)] = pt->pd->invalid_pte;
+}
+
+struct psb_mmu_pd *psb_mmu_get_default_pd(struct psb_mmu_driver *driver)
+{
+	struct psb_mmu_pd *pd;
+
+	down_read(&driver->sem);
+	pd = driver->default_pd;
+	up_read(&driver->sem);
+
+	return pd;
+}
+
+void psb_mmu_driver_takedown(struct psb_mmu_driver *driver)
+{
+	struct drm_device *dev = driver->dev;
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+
+	PSB_WSGX32(driver->bif_ctrl, PSB_CR_BIF_CTRL);
+	psb_mmu_free_pagedir(driver->default_pd);
+	kfree(driver);
+}
+
+struct psb_mmu_driver *psb_mmu_driver_init(struct drm_device *dev,
+					   int trap_pagefaults,
+					   int invalid_type,
+					   atomic_t *msvdx_mmu_invaldc)
+{
+	struct psb_mmu_driver *driver;
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+
+	driver = kmalloc(sizeof(*driver), GFP_KERNEL);
+
+	if (!driver)
+		return NULL;
+
+	driver->dev = dev;
+	driver->default_pd = psb_mmu_alloc_pd(driver, trap_pagefaults,
+					      invalid_type);
+	if (!driver->default_pd)
+		goto out_err1;
+
+	spin_lock_init(&driver->lock);
+	init_rwsem(&driver->sem);
+	down_write(&driver->sem);
+	atomic_set(&driver->needs_tlbflush, 1);
+	driver->msvdx_mmu_invaldc = msvdx_mmu_invaldc;
+
+	driver->bif_ctrl = PSB_RSGX32(PSB_CR_BIF_CTRL);
+	PSB_WSGX32(driver->bif_ctrl | _PSB_CB_CTRL_CLEAR_FAULT,
+		   PSB_CR_BIF_CTRL);
+	PSB_WSGX32(driver->bif_ctrl & ~_PSB_CB_CTRL_CLEAR_FAULT,
+		   PSB_CR_BIF_CTRL);
+
+	driver->has_clflush = 0;
+
+	if (boot_cpu_has(X86_FEATURE_CLFLUSH)) {
+		uint32_t tfms, misc, cap0, cap4, clflush_size;
+
+		/*
+		 * clflush size is determined at kernel setup for x86_64 but not
+		 * for i386. We have to do it here.
+		 */
+
+		cpuid(0x00000001, &tfms, &misc, &cap0, &cap4);
+		clflush_size = ((misc >> 8) & 0xff) * 8;
+		driver->has_clflush = 1;
+		driver->clflush_add =
+		    PAGE_SIZE * clflush_size / sizeof(uint32_t);
+		driver->clflush_mask = driver->clflush_add - 1;
+		driver->clflush_mask = ~driver->clflush_mask;
+	}
+
+	up_write(&driver->sem);
+	return driver;
+
+out_err1:
+	kfree(driver);
+	return NULL;
+}
+
+static void psb_mmu_flush_ptes(struct psb_mmu_pd *pd, unsigned long address,
+			       uint32_t num_pages, uint32_t desired_tile_stride,
+			       uint32_t hw_tile_stride)
+{
+	struct psb_mmu_pt *pt;
+	uint32_t rows = 1;
+	uint32_t i;
+	unsigned long addr;
+	unsigned long end;
+	unsigned long next;
+	unsigned long add;
+	unsigned long row_add;
+	unsigned long clflush_add = pd->driver->clflush_add;
+	unsigned long clflush_mask = pd->driver->clflush_mask;
+
+	if (!pd->driver->has_clflush)
+		return;
+
+	if (hw_tile_stride)
+		rows = num_pages / desired_tile_stride;
+	else
+		desired_tile_stride = num_pages;
+
+	add = desired_tile_stride << PAGE_SHIFT;
+	row_add = hw_tile_stride << PAGE_SHIFT;
+	mb();
+	for (i = 0; i < rows; ++i) {
+
+		addr = address;
+		end = addr + add;
+
+		do {
+			next = psb_pd_addr_end(addr, end);
+			pt = psb_mmu_pt_map_lock(pd, addr);
+			if (!pt)
+				continue;
+			do {
+				psb_clflush(&pt->v[psb_mmu_pt_index(addr)]);
+			} while (addr += clflush_add,
+				 (addr & clflush_mask) < next);
+
+			psb_mmu_pt_unmap_unlock(pt);
+		} while (addr = next, next != end);
+		address += row_add;
+	}
+	mb();
+}
+
+void psb_mmu_remove_pfn_sequence(struct psb_mmu_pd *pd,
+				 unsigned long address, uint32_t num_pages)
+{
+	struct psb_mmu_pt *pt;
+	unsigned long addr;
+	unsigned long end;
+	unsigned long next;
+	unsigned long f_address = address;
+
+	down_read(&pd->driver->sem);
+
+	addr = address;
+	end = addr + (num_pages << PAGE_SHIFT);
+
+	do {
+		next = psb_pd_addr_end(addr, end);
+		pt = psb_mmu_pt_alloc_map_lock(pd, addr);
+		if (!pt)
+			goto out;
+		do {
+			psb_mmu_invalidate_pte(pt, addr);
+			--pt->count;
+		} while (addr += PAGE_SIZE, addr < next);
+		psb_mmu_pt_unmap_unlock(pt);
+
+	} while (addr = next, next != end);
+
+out:
+	if (pd->hw_context != -1)
+		psb_mmu_flush_ptes(pd, f_address, num_pages, 1, 1);
+
+	up_read(&pd->driver->sem);
+
+	if (pd->hw_context != -1)
+		psb_mmu_flush(pd->driver);
+
+	return;
+}
+
+void psb_mmu_remove_pages(struct psb_mmu_pd *pd, unsigned long address,
+			  uint32_t num_pages, uint32_t desired_tile_stride,
+			  uint32_t hw_tile_stride)
+{
+	struct psb_mmu_pt *pt;
+	uint32_t rows = 1;
+	uint32_t i;
+	unsigned long addr;
+	unsigned long end;
+	unsigned long next;
+	unsigned long add;
+	unsigned long row_add;
+	unsigned long f_address = address;
+
+	if (hw_tile_stride)
+		rows = num_pages / desired_tile_stride;
+	else
+		desired_tile_stride = num_pages;
+
+	add = desired_tile_stride << PAGE_SHIFT;
+	row_add = hw_tile_stride << PAGE_SHIFT;
+
+	down_read(&pd->driver->sem);
+
+	/* Make sure we only need to flush this processor's cache */
+
+	for (i = 0; i < rows; ++i) {
+
+		addr = address;
+		end = addr + add;
+
+		do {
+			next = psb_pd_addr_end(addr, end);
+			pt = psb_mmu_pt_map_lock(pd, addr);
+			if (!pt)
+				continue;
+			do {
+				psb_mmu_invalidate_pte(pt, addr);
+				--pt->count;
+
+			} while (addr += PAGE_SIZE, addr < next);
+			psb_mmu_pt_unmap_unlock(pt);
+
+		} while (addr = next, next != end);
+		address += row_add;
+	}
+	if (pd->hw_context != -1)
+		psb_mmu_flush_ptes(pd, f_address, num_pages,
+				   desired_tile_stride, hw_tile_stride);
+
+	up_read(&pd->driver->sem);
+
+	if (pd->hw_context != -1)
+		psb_mmu_flush(pd->driver);
+}
+
+int psb_mmu_insert_pfn_sequence(struct psb_mmu_pd *pd, uint32_t start_pfn,
+				unsigned long address, uint32_t num_pages,
+				int type)
+{
+	struct psb_mmu_pt *pt;
+	uint32_t pte;
+	unsigned long addr;
+	unsigned long end;
+	unsigned long next;
+	unsigned long f_address = address;
+	int ret = -ENOMEM;
+
+	down_read(&pd->driver->sem);
+
+	addr = address;
+	end = addr + (num_pages << PAGE_SHIFT);
+
+	do {
+		next = psb_pd_addr_end(addr, end);
+		pt = psb_mmu_pt_alloc_map_lock(pd, addr);
+		if (!pt) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		do {
+			pte = psb_mmu_mask_pte(start_pfn++, type);
+			psb_mmu_set_pte(pt, addr, pte);
+			pt->count++;
+		} while (addr += PAGE_SIZE, addr < next);
+		psb_mmu_pt_unmap_unlock(pt);
+
+	} while (addr = next, next != end);
+	ret = 0;
+
+out:
+	if (pd->hw_context != -1)
+		psb_mmu_flush_ptes(pd, f_address, num_pages, 1, 1);
+
+	up_read(&pd->driver->sem);
+
+	if (pd->hw_context != -1)
+		psb_mmu_flush(pd->driver);
+
+	return ret;
+}
+
+int psb_mmu_insert_pages(struct psb_mmu_pd *pd, struct page **pages,
+			 unsigned long address, uint32_t num_pages,
+			 uint32_t desired_tile_stride, uint32_t hw_tile_stride,
+			 int type)
+{
+	struct psb_mmu_pt *pt;
+	uint32_t rows = 1;
+	uint32_t i;
+	uint32_t pte;
+	unsigned long addr;
+	unsigned long end;
+	unsigned long next;
+	unsigned long add;
+	unsigned long row_add;
+	unsigned long f_address = address;
+	int ret = -ENOMEM;
+
+	if (hw_tile_stride) {
+		if (num_pages % desired_tile_stride != 0)
+			return -EINVAL;
+		rows = num_pages / desired_tile_stride;
+	} else {
+		desired_tile_stride = num_pages;
+	}
+
+	add = desired_tile_stride << PAGE_SHIFT;
+	row_add = hw_tile_stride << PAGE_SHIFT;
+
+	down_read(&pd->driver->sem);
+
+	for (i = 0; i < rows; ++i) {
+
+		addr = address;
+		end = addr + add;
+
+		do {
+			next = psb_pd_addr_end(addr, end);
+			pt = psb_mmu_pt_alloc_map_lock(pd, addr);
+			if (!pt)
+				goto out;
+			do {
+				pte = psb_mmu_mask_pte(page_to_pfn(*pages++),
+						       type);
+				psb_mmu_set_pte(pt, addr, pte);
+				pt->count++;
+			} while (addr += PAGE_SIZE, addr < next);
+			psb_mmu_pt_unmap_unlock(pt);
+
+		} while (addr = next, next != end);
+
+		address += row_add;
+	}
+
+	ret = 0;
+out:
+	if (pd->hw_context != -1)
+		psb_mmu_flush_ptes(pd, f_address, num_pages,
+				   desired_tile_stride, hw_tile_stride);
+
+	up_read(&pd->driver->sem);
+
+	if (pd->hw_context != -1)
+		psb_mmu_flush(pd->driver);
+
+	return ret;
+}
+
+int psb_mmu_virtual_to_pfn(struct psb_mmu_pd *pd, uint32_t virtual,
+			   unsigned long *pfn)
+{
+	int ret;
+	struct psb_mmu_pt *pt;
+	uint32_t tmp;
+	spinlock_t *lock = &pd->driver->lock;
+
+	down_read(&pd->driver->sem);
+	pt = psb_mmu_pt_map_lock(pd, virtual);
+	if (!pt) {
+		uint32_t *v;
+
+		spin_lock(lock);
+		v = kmap_atomic(pd->p);
+		tmp = v[psb_mmu_pd_index(virtual)];
+		kunmap_atomic(v);
+		spin_unlock(lock);
+
+		if (tmp != pd->invalid_pde || !(tmp & PSB_PTE_VALID) ||
+		    !(pd->invalid_pte & PSB_PTE_VALID)) {
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = 0;
+		*pfn = pd->invalid_pte >> PAGE_SHIFT;
+		goto out;
+	}
+	tmp = pt->v[psb_mmu_pt_index(virtual)];
+	if (!(tmp & PSB_PTE_VALID)) {
+		ret = -EINVAL;
+	} else {
+		ret = 0;
+		*pfn = tmp >> PAGE_SHIFT;
+	}
+	psb_mmu_pt_unmap_unlock(pt);
+out:
+	up_read(&pd->driver->sem);
+	return ret;
+}