/**************************************************************************
* Copyright (c) 2007, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
**************************************************************************/
#include <drm/drmP.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.
*/
struct psb_mmu_driver {
/* protects driver- and pd structures. Always take in read mode
* before taking the page table spinlock.
*/
struct rw_semaphore sem;
/* protects page tables, directory tables and pt tables.
* and pt structures.
*/
spinlock_t lock;
atomic_t needs_tlbflush;
uint8_t __iomem *register_map;
struct psb_mmu_pd *default_pd;
/*uint32_t bif_ctrl;*/
int has_clflush;
int clflush_add;
unsigned long clflush_mask;
struct drm_psb_private *dev_priv;
};
struct psb_mmu_pd;
struct psb_mmu_pt {
struct psb_mmu_pd *pd;
uint32_t index;
uint32_t count;
struct page *p;
uint32_t *v;
};
struct psb_mmu_pd {
struct psb_mmu_driver *driver;
int hw_context;
struct psb_mmu_pt **tables;
struct page *p;
struct page *dummy_pt;
struct page *dummy_page;
uint32_t pd_mask;
uint32_t invalid_pde;
uint32_t invalid_pte;
};
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_page_clflush(struct psb_mmu_driver *driver, struct page* page)
{
uint32_t clflush_add = driver->clflush_add >> PAGE_SHIFT;
uint32_t clflush_count = PAGE_SIZE / clflush_add;
int i;
uint8_t *clf;
clf = kmap_atomic(page, KM_USER0);
mb();
for (i = 0; i < clflush_count; ++i) {
psb_clflush(clf);
clf += clflush_add;
}
mb();
kunmap_atomic(clf, KM_USER0);
}
static void psb_pages_clflush(struct psb_mmu_driver *driver,
struct page *page[], unsigned long num_pages)
{
int i;
if (!driver->has_clflush)
return ;
for (i = 0; i < num_pages; i++)
psb_page_clflush(driver, *page++);
}
static void psb_mmu_flush_pd_locked(struct psb_mmu_driver *driver,
int force)
{
atomic_set(&driver->needs_tlbflush, 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);
}
void psb_mmu_flush(struct psb_mmu_driver *driver, int rc_prot)
{
if (rc_prot)
down_write(&driver->sem);
if (rc_prot)
up_write(&driver->sem);
}
void psb_mmu_set_pd_context(struct psb_mmu_pd *pd, int hw_context)
{
/*ttm_tt_cache_flush(&pd->p, 1);*/
psb_pages_clflush(pd->driver, &pd->p, 1);
down_write(&pd->driver->sem);
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(pd->dummy_pt);
for (i = 0; i < (PAGE_SIZE / sizeof(uint32_t)); ++i)
v[i] = pd->invalid_pte;
kunmap(pd->dummy_pt);
v = kmap(pd->p);
for (i = 0; i < (PAGE_SIZE / sizeof(uint32_t)); ++i)
v[i] = pd->invalid_pde;
kunmap(pd->p);
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;
}
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 psb_mmu_pt *pt;
int i;
down_write(&driver->sem);
if (pd->hw_context != -1)
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, KM_USER0);
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, KM_USER0);
spin_unlock(lock);
pt->count = 0;
pt->pd = pd;
pt->index = 0;
return pt;
}
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, KM_USER0);
pd->tables[index] = pt;
v[index] = (page_to_pfn(pt->p) << 12) | pd->pd_mask;
pt->index = index;
kunmap_atomic((void *) v, KM_USER0);
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, KM_USER0);
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, KM_USER0);
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, KM_USER0);
if (pt->count == 0) {
v = kmap_atomic(pd->p, KM_USER0);
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(pt->v, KM_USER0);
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;
}
void psb_mmu_mirror_gtt(struct psb_mmu_pd *pd,
uint32_t mmu_offset, uint32_t gtt_start,
uint32_t gtt_pages)
{
uint32_t *v;
uint32_t start = psb_mmu_pd_index(mmu_offset);
struct psb_mmu_driver *driver = pd->driver;
int num_pages = gtt_pages;
down_read(&driver->sem);
spin_lock(&driver->lock);
v = kmap_atomic(pd->p, KM_USER0);
v += start;
while (gtt_pages--) {
*v++ = gtt_start | pd->pd_mask;
gtt_start += PAGE_SIZE;
}
/*ttm_tt_cache_flush(&pd->p, num_pages);*/
psb_pages_clflush(pd->driver, &pd->p, num_pages);
kunmap_atomic(v, KM_USER0);
spin_unlock(&driver->lock);
if (pd->hw_context != -1)
atomic_set(&pd->driver->needs_tlbflush, 1);
up_read(&pd->driver->sem);
psb_mmu_flush_pd(pd->driver, 0);
}
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)
{
psb_mmu_free_pagedir(driver->default_pd);
kfree(driver);
}
struct psb_mmu_driver *psb_mmu_driver_init(uint8_t __iomem * registers,
int trap_pagefaults,
int invalid_type,
struct drm_psb_private *dev_priv)
{
struct psb_mmu_driver *driver;
driver = kmalloc(sizeof(*driver), GFP_KERNEL);
if (!driver)
return NULL;
driver->dev_priv = dev_priv;
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);
driver->register_map = registers;
atomic_set(&driver->needs_tlbflush, 1);
driver->has_clflush = 0;
if (boot_cpu_has(X86_FEATURE_CLFLSH)) {
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) {
/*ttm_tt_cache_flush(&pd->p, num_pages);*/
psb_pages_clflush(pd->driver, &pd->p, num_pages);
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, 0);
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, 0);
}
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 = 0;
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);
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, 1);
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 = 0;
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) {
ret = -ENOMEM;
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;
}
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, 1);
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, KM_USER0);
tmp = v[psb_mmu_pd_index(virtual)];
kunmap_atomic(v, KM_USER0);
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;
}
