linux-sg2042/drivers/iommu/omap-iommu.c

1240 lines
26 KiB
C

/*
* omap iommu: tlb and pagetable primitives
*
* Copyright (C) 2008-2010 Nokia Corporation
*
* Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
* Paul Mundt and Toshihiro Kobayashi
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/err.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/iommu.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <asm/cacheflush.h>
#include <plat/iommu.h>
#include <plat/iopgtable.h>
#define for_each_iotlb_cr(obj, n, __i, cr) \
for (__i = 0; \
(__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true); \
__i++)
/* bitmap of the page sizes currently supported */
#define OMAP_IOMMU_PGSIZES (SZ_4K | SZ_64K | SZ_1M | SZ_16M)
/**
* struct omap_iommu_domain - omap iommu domain
* @pgtable: the page table
* @iommu_dev: an omap iommu device attached to this domain. only a single
* iommu device can be attached for now.
* @lock: domain lock, should be taken when attaching/detaching
*/
struct omap_iommu_domain {
u32 *pgtable;
struct omap_iommu *iommu_dev;
spinlock_t lock;
};
/* accommodate the difference between omap1 and omap2/3 */
static const struct iommu_functions *arch_iommu;
static struct platform_driver omap_iommu_driver;
static struct kmem_cache *iopte_cachep;
/**
* omap_install_iommu_arch - Install archtecure specific iommu functions
* @ops: a pointer to architecture specific iommu functions
*
* There are several kind of iommu algorithm(tlb, pagetable) among
* omap series. This interface installs such an iommu algorighm.
**/
int omap_install_iommu_arch(const struct iommu_functions *ops)
{
if (arch_iommu)
return -EBUSY;
arch_iommu = ops;
return 0;
}
EXPORT_SYMBOL_GPL(omap_install_iommu_arch);
/**
* omap_uninstall_iommu_arch - Uninstall archtecure specific iommu functions
* @ops: a pointer to architecture specific iommu functions
*
* This interface uninstalls the iommu algorighm installed previously.
**/
void omap_uninstall_iommu_arch(const struct iommu_functions *ops)
{
if (arch_iommu != ops)
pr_err("%s: not your arch\n", __func__);
arch_iommu = NULL;
}
EXPORT_SYMBOL_GPL(omap_uninstall_iommu_arch);
/**
* omap_iommu_save_ctx - Save registers for pm off-mode support
* @dev: client device
**/
void omap_iommu_save_ctx(struct device *dev)
{
struct omap_iommu *obj = dev_to_omap_iommu(dev);
arch_iommu->save_ctx(obj);
}
EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);
/**
* omap_iommu_restore_ctx - Restore registers for pm off-mode support
* @dev: client device
**/
void omap_iommu_restore_ctx(struct device *dev)
{
struct omap_iommu *obj = dev_to_omap_iommu(dev);
arch_iommu->restore_ctx(obj);
}
EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx);
/**
* omap_iommu_arch_version - Return running iommu arch version
**/
u32 omap_iommu_arch_version(void)
{
return arch_iommu->version;
}
EXPORT_SYMBOL_GPL(omap_iommu_arch_version);
static int iommu_enable(struct omap_iommu *obj)
{
int err;
if (!obj)
return -EINVAL;
if (!arch_iommu)
return -ENODEV;
clk_enable(obj->clk);
err = arch_iommu->enable(obj);
clk_disable(obj->clk);
return err;
}
static void iommu_disable(struct omap_iommu *obj)
{
if (!obj)
return;
clk_enable(obj->clk);
arch_iommu->disable(obj);
clk_disable(obj->clk);
}
/*
* TLB operations
*/
void omap_iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
{
BUG_ON(!cr || !e);
arch_iommu->cr_to_e(cr, e);
}
EXPORT_SYMBOL_GPL(omap_iotlb_cr_to_e);
static inline int iotlb_cr_valid(struct cr_regs *cr)
{
if (!cr)
return -EINVAL;
return arch_iommu->cr_valid(cr);
}
static inline struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
struct iotlb_entry *e)
{
if (!e)
return NULL;
return arch_iommu->alloc_cr(obj, e);
}
static u32 iotlb_cr_to_virt(struct cr_regs *cr)
{
return arch_iommu->cr_to_virt(cr);
}
static u32 get_iopte_attr(struct iotlb_entry *e)
{
return arch_iommu->get_pte_attr(e);
}
static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da)
{
return arch_iommu->fault_isr(obj, da);
}
static void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l)
{
u32 val;
val = iommu_read_reg(obj, MMU_LOCK);
l->base = MMU_LOCK_BASE(val);
l->vict = MMU_LOCK_VICT(val);
}
static void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l)
{
u32 val;
val = (l->base << MMU_LOCK_BASE_SHIFT);
val |= (l->vict << MMU_LOCK_VICT_SHIFT);
iommu_write_reg(obj, val, MMU_LOCK);
}
static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
{
arch_iommu->tlb_read_cr(obj, cr);
}
static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr)
{
arch_iommu->tlb_load_cr(obj, cr);
iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
iommu_write_reg(obj, 1, MMU_LD_TLB);
}
/**
* iotlb_dump_cr - Dump an iommu tlb entry into buf
* @obj: target iommu
* @cr: contents of cam and ram register
* @buf: output buffer
**/
static inline ssize_t iotlb_dump_cr(struct omap_iommu *obj, struct cr_regs *cr,
char *buf)
{
BUG_ON(!cr || !buf);
return arch_iommu->dump_cr(obj, cr, buf);
}
/* only used in iotlb iteration for-loop */
static struct cr_regs __iotlb_read_cr(struct omap_iommu *obj, int n)
{
struct cr_regs cr;
struct iotlb_lock l;
iotlb_lock_get(obj, &l);
l.vict = n;
iotlb_lock_set(obj, &l);
iotlb_read_cr(obj, &cr);
return cr;
}
/**
* load_iotlb_entry - Set an iommu tlb entry
* @obj: target iommu
* @e: an iommu tlb entry info
**/
#ifdef PREFETCH_IOTLB
static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
{
int err = 0;
struct iotlb_lock l;
struct cr_regs *cr;
if (!obj || !obj->nr_tlb_entries || !e)
return -EINVAL;
clk_enable(obj->clk);
iotlb_lock_get(obj, &l);
if (l.base == obj->nr_tlb_entries) {
dev_warn(obj->dev, "%s: preserve entries full\n", __func__);
err = -EBUSY;
goto out;
}
if (!e->prsvd) {
int i;
struct cr_regs tmp;
for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
if (!iotlb_cr_valid(&tmp))
break;
if (i == obj->nr_tlb_entries) {
dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
err = -EBUSY;
goto out;
}
iotlb_lock_get(obj, &l);
} else {
l.vict = l.base;
iotlb_lock_set(obj, &l);
}
cr = iotlb_alloc_cr(obj, e);
if (IS_ERR(cr)) {
clk_disable(obj->clk);
return PTR_ERR(cr);
}
iotlb_load_cr(obj, cr);
kfree(cr);
if (e->prsvd)
l.base++;
/* increment victim for next tlb load */
if (++l.vict == obj->nr_tlb_entries)
l.vict = l.base;
iotlb_lock_set(obj, &l);
out:
clk_disable(obj->clk);
return err;
}
#else /* !PREFETCH_IOTLB */
static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
{
return 0;
}
#endif /* !PREFETCH_IOTLB */
static int prefetch_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
{
return load_iotlb_entry(obj, e);
}
/**
* flush_iotlb_page - Clear an iommu tlb entry
* @obj: target iommu
* @da: iommu device virtual address
*
* Clear an iommu tlb entry which includes 'da' address.
**/
static void flush_iotlb_page(struct omap_iommu *obj, u32 da)
{
int i;
struct cr_regs cr;
clk_enable(obj->clk);
for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) {
u32 start;
size_t bytes;
if (!iotlb_cr_valid(&cr))
continue;
start = iotlb_cr_to_virt(&cr);
bytes = iopgsz_to_bytes(cr.cam & 3);
if ((start <= da) && (da < start + bytes)) {
dev_dbg(obj->dev, "%s: %08x<=%08x(%x)\n",
__func__, start, da, bytes);
iotlb_load_cr(obj, &cr);
iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
}
}
clk_disable(obj->clk);
if (i == obj->nr_tlb_entries)
dev_dbg(obj->dev, "%s: no page for %08x\n", __func__, da);
}
/**
* flush_iotlb_all - Clear all iommu tlb entries
* @obj: target iommu
**/
static void flush_iotlb_all(struct omap_iommu *obj)
{
struct iotlb_lock l;
clk_enable(obj->clk);
l.base = 0;
l.vict = 0;
iotlb_lock_set(obj, &l);
iommu_write_reg(obj, 1, MMU_GFLUSH);
clk_disable(obj->clk);
}
#if defined(CONFIG_OMAP_IOMMU_DEBUG) || defined(CONFIG_OMAP_IOMMU_DEBUG_MODULE)
ssize_t omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t bytes)
{
if (!obj || !buf)
return -EINVAL;
clk_enable(obj->clk);
bytes = arch_iommu->dump_ctx(obj, buf, bytes);
clk_disable(obj->clk);
return bytes;
}
EXPORT_SYMBOL_GPL(omap_iommu_dump_ctx);
static int
__dump_tlb_entries(struct omap_iommu *obj, struct cr_regs *crs, int num)
{
int i;
struct iotlb_lock saved;
struct cr_regs tmp;
struct cr_regs *p = crs;
clk_enable(obj->clk);
iotlb_lock_get(obj, &saved);
for_each_iotlb_cr(obj, num, i, tmp) {
if (!iotlb_cr_valid(&tmp))
continue;
*p++ = tmp;
}
iotlb_lock_set(obj, &saved);
clk_disable(obj->clk);
return p - crs;
}
/**
* omap_dump_tlb_entries - dump cr arrays to given buffer
* @obj: target iommu
* @buf: output buffer
**/
size_t omap_dump_tlb_entries(struct omap_iommu *obj, char *buf, ssize_t bytes)
{
int i, num;
struct cr_regs *cr;
char *p = buf;
num = bytes / sizeof(*cr);
num = min(obj->nr_tlb_entries, num);
cr = kcalloc(num, sizeof(*cr), GFP_KERNEL);
if (!cr)
return 0;
num = __dump_tlb_entries(obj, cr, num);
for (i = 0; i < num; i++)
p += iotlb_dump_cr(obj, cr + i, p);
kfree(cr);
return p - buf;
}
EXPORT_SYMBOL_GPL(omap_dump_tlb_entries);
int omap_foreach_iommu_device(void *data, int (*fn)(struct device *, void *))
{
return driver_for_each_device(&omap_iommu_driver.driver,
NULL, data, fn);
}
EXPORT_SYMBOL_GPL(omap_foreach_iommu_device);
#endif /* CONFIG_OMAP_IOMMU_DEBUG_MODULE */
/*
* H/W pagetable operations
*/
static void flush_iopgd_range(u32 *first, u32 *last)
{
/* FIXME: L2 cache should be taken care of if it exists */
do {
asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pgd"
: : "r" (first));
first += L1_CACHE_BYTES / sizeof(*first);
} while (first <= last);
}
static void flush_iopte_range(u32 *first, u32 *last)
{
/* FIXME: L2 cache should be taken care of if it exists */
do {
asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pte"
: : "r" (first));
first += L1_CACHE_BYTES / sizeof(*first);
} while (first <= last);
}
static void iopte_free(u32 *iopte)
{
/* Note: freed iopte's must be clean ready for re-use */
kmem_cache_free(iopte_cachep, iopte);
}
static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd, u32 da)
{
u32 *iopte;
/* a table has already existed */
if (*iopgd)
goto pte_ready;
/*
* do the allocation outside the page table lock
*/
spin_unlock(&obj->page_table_lock);
iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL);
spin_lock(&obj->page_table_lock);
if (!*iopgd) {
if (!iopte)
return ERR_PTR(-ENOMEM);
*iopgd = virt_to_phys(iopte) | IOPGD_TABLE;
flush_iopgd_range(iopgd, iopgd);
dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte);
} else {
/* We raced, free the reduniovant table */
iopte_free(iopte);
}
pte_ready:
iopte = iopte_offset(iopgd, da);
dev_vdbg(obj->dev,
"%s: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n",
__func__, da, iopgd, *iopgd, iopte, *iopte);
return iopte;
}
static int iopgd_alloc_section(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
{
u32 *iopgd = iopgd_offset(obj, da);
if ((da | pa) & ~IOSECTION_MASK) {
dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
__func__, da, pa, IOSECTION_SIZE);
return -EINVAL;
}
*iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION;
flush_iopgd_range(iopgd, iopgd);
return 0;
}
static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
{
u32 *iopgd = iopgd_offset(obj, da);
int i;
if ((da | pa) & ~IOSUPER_MASK) {
dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
__func__, da, pa, IOSUPER_SIZE);
return -EINVAL;
}
for (i = 0; i < 16; i++)
*(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER;
flush_iopgd_range(iopgd, iopgd + 15);
return 0;
}
static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
{
u32 *iopgd = iopgd_offset(obj, da);
u32 *iopte = iopte_alloc(obj, iopgd, da);
if (IS_ERR(iopte))
return PTR_ERR(iopte);
*iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL;
flush_iopte_range(iopte, iopte);
dev_vdbg(obj->dev, "%s: da:%08x pa:%08x pte:%p *pte:%08x\n",
__func__, da, pa, iopte, *iopte);
return 0;
}
static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
{
u32 *iopgd = iopgd_offset(obj, da);
u32 *iopte = iopte_alloc(obj, iopgd, da);
int i;
if ((da | pa) & ~IOLARGE_MASK) {
dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
__func__, da, pa, IOLARGE_SIZE);
return -EINVAL;
}
if (IS_ERR(iopte))
return PTR_ERR(iopte);
for (i = 0; i < 16; i++)
*(iopte + i) = (pa & IOLARGE_MASK) | prot | IOPTE_LARGE;
flush_iopte_range(iopte, iopte + 15);
return 0;
}
static int
iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e)
{
int (*fn)(struct omap_iommu *, u32, u32, u32);
u32 prot;
int err;
if (!obj || !e)
return -EINVAL;
switch (e->pgsz) {
case MMU_CAM_PGSZ_16M:
fn = iopgd_alloc_super;
break;
case MMU_CAM_PGSZ_1M:
fn = iopgd_alloc_section;
break;
case MMU_CAM_PGSZ_64K:
fn = iopte_alloc_large;
break;
case MMU_CAM_PGSZ_4K:
fn = iopte_alloc_page;
break;
default:
fn = NULL;
BUG();
break;
}
prot = get_iopte_attr(e);
spin_lock(&obj->page_table_lock);
err = fn(obj, e->da, e->pa, prot);
spin_unlock(&obj->page_table_lock);
return err;
}
/**
* omap_iopgtable_store_entry - Make an iommu pte entry
* @obj: target iommu
* @e: an iommu tlb entry info
**/
int omap_iopgtable_store_entry(struct omap_iommu *obj, struct iotlb_entry *e)
{
int err;
flush_iotlb_page(obj, e->da);
err = iopgtable_store_entry_core(obj, e);
if (!err)
prefetch_iotlb_entry(obj, e);
return err;
}
EXPORT_SYMBOL_GPL(omap_iopgtable_store_entry);
/**
* iopgtable_lookup_entry - Lookup an iommu pte entry
* @obj: target iommu
* @da: iommu device virtual address
* @ppgd: iommu pgd entry pointer to be returned
* @ppte: iommu pte entry pointer to be returned
**/
static void
iopgtable_lookup_entry(struct omap_iommu *obj, u32 da, u32 **ppgd, u32 **ppte)
{
u32 *iopgd, *iopte = NULL;
iopgd = iopgd_offset(obj, da);
if (!*iopgd)
goto out;
if (iopgd_is_table(*iopgd))
iopte = iopte_offset(iopgd, da);
out:
*ppgd = iopgd;
*ppte = iopte;
}
static size_t iopgtable_clear_entry_core(struct omap_iommu *obj, u32 da)
{
size_t bytes;
u32 *iopgd = iopgd_offset(obj, da);
int nent = 1;
if (!*iopgd)
return 0;
if (iopgd_is_table(*iopgd)) {
int i;
u32 *iopte = iopte_offset(iopgd, da);
bytes = IOPTE_SIZE;
if (*iopte & IOPTE_LARGE) {
nent *= 16;
/* rewind to the 1st entry */
iopte = iopte_offset(iopgd, (da & IOLARGE_MASK));
}
bytes *= nent;
memset(iopte, 0, nent * sizeof(*iopte));
flush_iopte_range(iopte, iopte + (nent - 1) * sizeof(*iopte));
/*
* do table walk to check if this table is necessary or not
*/
iopte = iopte_offset(iopgd, 0);
for (i = 0; i < PTRS_PER_IOPTE; i++)
if (iopte[i])
goto out;
iopte_free(iopte);
nent = 1; /* for the next L1 entry */
} else {
bytes = IOPGD_SIZE;
if ((*iopgd & IOPGD_SUPER) == IOPGD_SUPER) {
nent *= 16;
/* rewind to the 1st entry */
iopgd = iopgd_offset(obj, (da & IOSUPER_MASK));
}
bytes *= nent;
}
memset(iopgd, 0, nent * sizeof(*iopgd));
flush_iopgd_range(iopgd, iopgd + (nent - 1) * sizeof(*iopgd));
out:
return bytes;
}
/**
* iopgtable_clear_entry - Remove an iommu pte entry
* @obj: target iommu
* @da: iommu device virtual address
**/
static size_t iopgtable_clear_entry(struct omap_iommu *obj, u32 da)
{
size_t bytes;
spin_lock(&obj->page_table_lock);
bytes = iopgtable_clear_entry_core(obj, da);
flush_iotlb_page(obj, da);
spin_unlock(&obj->page_table_lock);
return bytes;
}
static void iopgtable_clear_entry_all(struct omap_iommu *obj)
{
int i;
spin_lock(&obj->page_table_lock);
for (i = 0; i < PTRS_PER_IOPGD; i++) {
u32 da;
u32 *iopgd;
da = i << IOPGD_SHIFT;
iopgd = iopgd_offset(obj, da);
if (!*iopgd)
continue;
if (iopgd_is_table(*iopgd))
iopte_free(iopte_offset(iopgd, 0));
*iopgd = 0;
flush_iopgd_range(iopgd, iopgd);
}
flush_iotlb_all(obj);
spin_unlock(&obj->page_table_lock);
}
/*
* Device IOMMU generic operations
*/
static irqreturn_t iommu_fault_handler(int irq, void *data)
{
u32 da, errs;
u32 *iopgd, *iopte;
struct omap_iommu *obj = data;
struct iommu_domain *domain = obj->domain;
if (!obj->refcount)
return IRQ_NONE;
clk_enable(obj->clk);
errs = iommu_report_fault(obj, &da);
clk_disable(obj->clk);
if (errs == 0)
return IRQ_HANDLED;
/* Fault callback or TLB/PTE Dynamic loading */
if (!report_iommu_fault(domain, obj->dev, da, 0))
return IRQ_HANDLED;
iommu_disable(obj);
iopgd = iopgd_offset(obj, da);
if (!iopgd_is_table(*iopgd)) {
dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p "
"*pgd:px%08x\n", obj->name, errs, da, iopgd, *iopgd);
return IRQ_NONE;
}
iopte = iopte_offset(iopgd, da);
dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:0x%08x "
"pte:0x%p *pte:0x%08x\n", obj->name, errs, da, iopgd, *iopgd,
iopte, *iopte);
return IRQ_NONE;
}
static int device_match_by_alias(struct device *dev, void *data)
{
struct omap_iommu *obj = to_iommu(dev);
const char *name = data;
pr_debug("%s: %s %s\n", __func__, obj->name, name);
return strcmp(obj->name, name) == 0;
}
/**
* omap_iommu_attach() - attach iommu device to an iommu domain
* @name: name of target omap iommu device
* @iopgd: page table
**/
static struct omap_iommu *omap_iommu_attach(const char *name, u32 *iopgd)
{
int err = -ENOMEM;
struct device *dev;
struct omap_iommu *obj;
dev = driver_find_device(&omap_iommu_driver.driver, NULL,
(void *)name,
device_match_by_alias);
if (!dev)
return NULL;
obj = to_iommu(dev);
spin_lock(&obj->iommu_lock);
/* an iommu device can only be attached once */
if (++obj->refcount > 1) {
dev_err(dev, "%s: already attached!\n", obj->name);
err = -EBUSY;
goto err_enable;
}
obj->iopgd = iopgd;
err = iommu_enable(obj);
if (err)
goto err_enable;
flush_iotlb_all(obj);
if (!try_module_get(obj->owner))
goto err_module;
spin_unlock(&obj->iommu_lock);
dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
return obj;
err_module:
if (obj->refcount == 1)
iommu_disable(obj);
err_enable:
obj->refcount--;
spin_unlock(&obj->iommu_lock);
return ERR_PTR(err);
}
/**
* omap_iommu_detach - release iommu device
* @obj: target iommu
**/
static void omap_iommu_detach(struct omap_iommu *obj)
{
if (!obj || IS_ERR(obj))
return;
spin_lock(&obj->iommu_lock);
if (--obj->refcount == 0)
iommu_disable(obj);
module_put(obj->owner);
obj->iopgd = NULL;
spin_unlock(&obj->iommu_lock);
dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
}
/*
* OMAP Device MMU(IOMMU) detection
*/
static int __devinit omap_iommu_probe(struct platform_device *pdev)
{
int err = -ENODEV;
int irq;
struct omap_iommu *obj;
struct resource *res;
struct iommu_platform_data *pdata = pdev->dev.platform_data;
if (pdev->num_resources != 2)
return -EINVAL;
obj = kzalloc(sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
if (!obj)
return -ENOMEM;
obj->clk = clk_get(&pdev->dev, pdata->clk_name);
if (IS_ERR(obj->clk))
goto err_clk;
obj->nr_tlb_entries = pdata->nr_tlb_entries;
obj->name = pdata->name;
obj->dev = &pdev->dev;
obj->ctx = (void *)obj + sizeof(*obj);
obj->da_start = pdata->da_start;
obj->da_end = pdata->da_end;
spin_lock_init(&obj->iommu_lock);
mutex_init(&obj->mmap_lock);
spin_lock_init(&obj->page_table_lock);
INIT_LIST_HEAD(&obj->mmap);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
err = -ENODEV;
goto err_mem;
}
res = request_mem_region(res->start, resource_size(res),
dev_name(&pdev->dev));
if (!res) {
err = -EIO;
goto err_mem;
}
obj->regbase = ioremap(res->start, resource_size(res));
if (!obj->regbase) {
err = -ENOMEM;
goto err_ioremap;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
err = -ENODEV;
goto err_irq;
}
err = request_irq(irq, iommu_fault_handler, IRQF_SHARED,
dev_name(&pdev->dev), obj);
if (err < 0)
goto err_irq;
platform_set_drvdata(pdev, obj);
dev_info(&pdev->dev, "%s registered\n", obj->name);
return 0;
err_irq:
iounmap(obj->regbase);
err_ioremap:
release_mem_region(res->start, resource_size(res));
err_mem:
clk_put(obj->clk);
err_clk:
kfree(obj);
return err;
}
static int __devexit omap_iommu_remove(struct platform_device *pdev)
{
int irq;
struct resource *res;
struct omap_iommu *obj = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
iopgtable_clear_entry_all(obj);
irq = platform_get_irq(pdev, 0);
free_irq(irq, obj);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(res->start, resource_size(res));
iounmap(obj->regbase);
clk_put(obj->clk);
dev_info(&pdev->dev, "%s removed\n", obj->name);
kfree(obj);
return 0;
}
static struct platform_driver omap_iommu_driver = {
.probe = omap_iommu_probe,
.remove = __devexit_p(omap_iommu_remove),
.driver = {
.name = "omap-iommu",
},
};
static void iopte_cachep_ctor(void *iopte)
{
clean_dcache_area(iopte, IOPTE_TABLE_SIZE);
}
static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
phys_addr_t pa, size_t bytes, int prot)
{
struct omap_iommu_domain *omap_domain = domain->priv;
struct omap_iommu *oiommu = omap_domain->iommu_dev;
struct device *dev = oiommu->dev;
struct iotlb_entry e;
int omap_pgsz;
u32 ret, flags;
/* we only support mapping a single iommu page for now */
omap_pgsz = bytes_to_iopgsz(bytes);
if (omap_pgsz < 0) {
dev_err(dev, "invalid size to map: %d\n", bytes);
return -EINVAL;
}
dev_dbg(dev, "mapping da 0x%lx to pa 0x%x size 0x%x\n", da, pa, bytes);
flags = omap_pgsz | prot;
iotlb_init_entry(&e, da, pa, flags);
ret = omap_iopgtable_store_entry(oiommu, &e);
if (ret)
dev_err(dev, "omap_iopgtable_store_entry failed: %d\n", ret);
return ret;
}
static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
size_t size)
{
struct omap_iommu_domain *omap_domain = domain->priv;
struct omap_iommu *oiommu = omap_domain->iommu_dev;
struct device *dev = oiommu->dev;
dev_dbg(dev, "unmapping da 0x%lx size %u\n", da, size);
return iopgtable_clear_entry(oiommu, da);
}
static int
omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
{
struct omap_iommu_domain *omap_domain = domain->priv;
struct omap_iommu *oiommu;
struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
int ret = 0;
spin_lock(&omap_domain->lock);
/* only a single device is supported per domain for now */
if (omap_domain->iommu_dev) {
dev_err(dev, "iommu domain is already attached\n");
ret = -EBUSY;
goto out;
}
/* get a handle to and enable the omap iommu */
oiommu = omap_iommu_attach(arch_data->name, omap_domain->pgtable);
if (IS_ERR(oiommu)) {
ret = PTR_ERR(oiommu);
dev_err(dev, "can't get omap iommu: %d\n", ret);
goto out;
}
omap_domain->iommu_dev = arch_data->iommu_dev = oiommu;
oiommu->domain = domain;
out:
spin_unlock(&omap_domain->lock);
return ret;
}
static void omap_iommu_detach_dev(struct iommu_domain *domain,
struct device *dev)
{
struct omap_iommu_domain *omap_domain = domain->priv;
struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
struct omap_iommu *oiommu = dev_to_omap_iommu(dev);
spin_lock(&omap_domain->lock);
/* only a single device is supported per domain for now */
if (omap_domain->iommu_dev != oiommu) {
dev_err(dev, "invalid iommu device\n");
goto out;
}
iopgtable_clear_entry_all(oiommu);
omap_iommu_detach(oiommu);
omap_domain->iommu_dev = arch_data->iommu_dev = NULL;
out:
spin_unlock(&omap_domain->lock);
}
static int omap_iommu_domain_init(struct iommu_domain *domain)
{
struct omap_iommu_domain *omap_domain;
omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL);
if (!omap_domain) {
pr_err("kzalloc failed\n");
goto out;
}
omap_domain->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_KERNEL);
if (!omap_domain->pgtable) {
pr_err("kzalloc failed\n");
goto fail_nomem;
}
/*
* should never fail, but please keep this around to ensure
* we keep the hardware happy
*/
BUG_ON(!IS_ALIGNED((long)omap_domain->pgtable, IOPGD_TABLE_SIZE));
clean_dcache_area(omap_domain->pgtable, IOPGD_TABLE_SIZE);
spin_lock_init(&omap_domain->lock);
domain->priv = omap_domain;
return 0;
fail_nomem:
kfree(omap_domain);
out:
return -ENOMEM;
}
/* assume device was already detached */
static void omap_iommu_domain_destroy(struct iommu_domain *domain)
{
struct omap_iommu_domain *omap_domain = domain->priv;
domain->priv = NULL;
kfree(omap_domain->pgtable);
kfree(omap_domain);
}
static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain,
unsigned long da)
{
struct omap_iommu_domain *omap_domain = domain->priv;
struct omap_iommu *oiommu = omap_domain->iommu_dev;
struct device *dev = oiommu->dev;
u32 *pgd, *pte;
phys_addr_t ret = 0;
iopgtable_lookup_entry(oiommu, da, &pgd, &pte);
if (pte) {
if (iopte_is_small(*pte))
ret = omap_iommu_translate(*pte, da, IOPTE_MASK);
else if (iopte_is_large(*pte))
ret = omap_iommu_translate(*pte, da, IOLARGE_MASK);
else
dev_err(dev, "bogus pte 0x%x, da 0x%lx", *pte, da);
} else {
if (iopgd_is_section(*pgd))
ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK);
else if (iopgd_is_super(*pgd))
ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK);
else
dev_err(dev, "bogus pgd 0x%x, da 0x%lx", *pgd, da);
}
return ret;
}
static int omap_iommu_domain_has_cap(struct iommu_domain *domain,
unsigned long cap)
{
return 0;
}
static struct iommu_ops omap_iommu_ops = {
.domain_init = omap_iommu_domain_init,
.domain_destroy = omap_iommu_domain_destroy,
.attach_dev = omap_iommu_attach_dev,
.detach_dev = omap_iommu_detach_dev,
.map = omap_iommu_map,
.unmap = omap_iommu_unmap,
.iova_to_phys = omap_iommu_iova_to_phys,
.domain_has_cap = omap_iommu_domain_has_cap,
.pgsize_bitmap = OMAP_IOMMU_PGSIZES,
};
static int __init omap_iommu_init(void)
{
struct kmem_cache *p;
const unsigned long flags = SLAB_HWCACHE_ALIGN;
size_t align = 1 << 10; /* L2 pagetable alignement */
p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags,
iopte_cachep_ctor);
if (!p)
return -ENOMEM;
iopte_cachep = p;
bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
return platform_driver_register(&omap_iommu_driver);
}
module_init(omap_iommu_init);
static void __exit omap_iommu_exit(void)
{
kmem_cache_destroy(iopte_cachep);
platform_driver_unregister(&omap_iommu_driver);
}
module_exit(omap_iommu_exit);
MODULE_DESCRIPTION("omap iommu: tlb and pagetable primitives");
MODULE_ALIAS("platform:omap-iommu");
MODULE_AUTHOR("Hiroshi DOYU, Paul Mundt and Toshihiro Kobayashi");
MODULE_LICENSE("GPL v2");