The OMAP IOMMU driver supports both the OMAP1 and OMAP2+ IOMMU variants
by splitting the driver into a core module and a thin arch-specific
operations module.
(In practice only the OMAP2+ module omap-iommu2 is implemented, but
let's not denigrate the effort.)
The arch-specific operations module registers itself with the OMAP IOMMU
core module at initialization time. This initializes a module global
arch-specific operations pointer, used at runtime by the IOMMU
instances.
This scheme causes several issues. In addition to making it impossible
to support different OMAP IOMMU types in a single system (which in all
fairness is quite unlikely to happen), it also causes initialization
ordering issues by requiring the arch-specific operations module to be
loaded before any IOMMU user. This results in a probe breakage with the
OMAP3 ISP driver when not compiled as a module.
Fix the problem by inverting the dependency. Instead of having the
omap-iommu2 module register itself to iommu-omap, make the iommu-omap
retrieve the omap-iommu2 operations structure directly when probing the
IOMMU device. This ensures that a probed IOMMU will always have valid
arch-specific operations.
As the arch-specific operations pointer is now initialized at probe
time, this change requires turning it from a global variable into a
per-device variable.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/iommu/omap-iommu-debug.c | 6 ++-
drivers/iommu/omap-iommu.c | 94 ++++++++++++++--------------------------
drivers/iommu/omap-iommu.h | 10 ++++-
drivers/iommu/omap-iommu2.c | 18 +-------
4 files changed, 45 insertions(+), 83 deletions(-)
diff --git a/drivers/iommu/omap-iommu-debug.c b/drivers/iommu/omap-iommu-debug.c
index 531658d..35a2c3a 100644
--- a/drivers/iommu/omap-iommu-debug.c
+++ b/drivers/iommu/omap-iommu-debug.c
@@ -33,7 +33,9 @@ static struct dentry *iommu_debug_root;
static ssize_t debug_read_ver(struct file *file, char __user *userbuf,
size_t count, loff_t *ppos)
{
- u32 ver = omap_iommu_arch_version();
+ struct device *dev = file->private_data;
+ struct omap_iommu *obj = dev_to_omap_iommu(dev);
+ u32 ver = omap_iommu_arch_version(obj);
char buf[MAXCOLUMN], *p = buf;
p += sprintf(p, "H/W version: %d.%d\n", (ver >> 4) & 0xf , ver & 0xf);
@@ -117,7 +119,7 @@ static ssize_t debug_write_pagetable(struct file *file,
return -EINVAL;
}
- omap_iotlb_cr_to_e(&cr, &e);
+ omap_iotlb_cr_to_e(obj, &cr, &e);
err = omap_iopgtable_store_entry(obj, &e);
if (err)
dev_err(obj->dev, "%s: fail to store cr\n", __func__);
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index df579f8..192c367 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -76,45 +76,10 @@ struct iotlb_lock {
short vict;
};
-/* 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
**/
@@ -122,7 +87,7 @@ void omap_iommu_save_ctx(struct device *dev)
{
struct omap_iommu *obj = dev_to_omap_iommu(dev);
- arch_iommu->save_ctx(obj);
+ obj->arch_iommu->save_ctx(obj);
}
EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);
@@ -134,16 +99,16 @@ void omap_iommu_restore_ctx(struct device *dev)
{
struct omap_iommu *obj = dev_to_omap_iommu(dev);
- arch_iommu->restore_ctx(obj);
+ obj->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)
+u32 omap_iommu_arch_version(struct omap_iommu *obj)
{
- return arch_iommu->version;
+ return obj->arch_iommu->version;
}
EXPORT_SYMBOL_GPL(omap_iommu_arch_version);
@@ -153,7 +118,7 @@ static int iommu_enable(struct omap_iommu *obj)
struct platform_device *pdev = to_platform_device(obj->dev);
struct iommu_platform_data *pdata = pdev->dev.platform_data;
- if (!arch_iommu)
+ if (!obj->arch_iommu)
return -ENODEV;
if (pdata && pdata->deassert_reset) {
@@ -166,7 +131,7 @@ static int iommu_enable(struct omap_iommu *obj)
pm_runtime_get_sync(obj->dev);
- err = arch_iommu->enable(obj);
+ err = obj->arch_iommu->enable(obj);
return err;
}
@@ -176,7 +141,7 @@ static void iommu_disable(struct omap_iommu *obj)
struct platform_device *pdev = to_platform_device(obj->dev);
struct iommu_platform_data *pdata = pdev->dev.platform_data;
- arch_iommu->disable(obj);
+ obj->arch_iommu->disable(obj);
pm_runtime_put_sync(obj->dev);
@@ -187,20 +152,21 @@ static void iommu_disable(struct omap_iommu *obj)
/*
* TLB operations
*/
-void omap_iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
+void omap_iotlb_cr_to_e(struct omap_iommu *obj, struct cr_regs *cr,
+ struct iotlb_entry *e)
{
BUG_ON(!cr || !e);
- arch_iommu->cr_to_e(cr, e);
+ obj->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)
+static inline int iotlb_cr_valid(struct omap_iommu *obj, struct cr_regs *cr)
{
if (!cr)
return -EINVAL;
- return arch_iommu->cr_valid(cr);
+ return obj->arch_iommu->cr_valid(cr);
}
static inline struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
@@ -209,22 +175,22 @@ static inline struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
if (!e)
return NULL;
- return arch_iommu->alloc_cr(obj, e);
+ return obj->arch_iommu->alloc_cr(obj, e);
}
-static u32 iotlb_cr_to_virt(struct cr_regs *cr)
+static u32 iotlb_cr_to_virt(struct omap_iommu *obj, struct cr_regs *cr)
{
- return arch_iommu->cr_to_virt(cr);
+ return obj->arch_iommu->cr_to_virt(cr);
}
-static u32 get_iopte_attr(struct iotlb_entry *e)
+static u32 get_iopte_attr(struct omap_iommu *obj, struct iotlb_entry *e)
{
- return arch_iommu->get_pte_attr(e);
+ return obj->arch_iommu->get_pte_attr(e);
}
static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da)
{
- return arch_iommu->fault_isr(obj, da);
+ return obj->arch_iommu->fault_isr(obj, da);
}
static void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l)
@@ -250,12 +216,12 @@ static void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l)
static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
{
- arch_iommu->tlb_read_cr(obj, cr);
+ obj->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);
+ obj->arch_iommu->tlb_load_cr(obj, cr);
iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
iommu_write_reg(obj, 1, MMU_LD_TLB);
@@ -272,7 +238,7 @@ static inline ssize_t iotlb_dump_cr(struct omap_iommu *obj, struct cr_regs *cr,
{
BUG_ON(!cr || !buf);
- return arch_iommu->dump_cr(obj, cr, buf);
+ return obj->arch_iommu->dump_cr(obj, cr, buf);
}
/* only used in iotlb iteration for-loop */
@@ -317,7 +283,7 @@ static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
struct cr_regs tmp;
for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
- if (!iotlb_cr_valid(&tmp))
+ if (!iotlb_cr_valid(obj, &tmp))
break;
if (i == obj->nr_tlb_entries) {
@@ -384,10 +350,10 @@ static void flush_iotlb_page(struct omap_iommu *obj, u32 da)
u32 start;
size_t bytes;
- if (!iotlb_cr_valid(&cr))
+ if (!iotlb_cr_valid(obj, &cr))
continue;
- start = iotlb_cr_to_virt(&cr);
+ start = iotlb_cr_to_virt(obj, &cr);
bytes = iopgsz_to_bytes(cr.cam & 3);
if ((start <= da) && (da < start + bytes)) {
@@ -432,7 +398,7 @@ ssize_t omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t bytes)
pm_runtime_get_sync(obj->dev);
- bytes = arch_iommu->dump_ctx(obj, buf, bytes);
+ bytes = obj->arch_iommu->dump_ctx(obj, buf, bytes);
pm_runtime_put_sync(obj->dev);
@@ -452,7 +418,7 @@ __dump_tlb_entries(struct omap_iommu *obj, struct cr_regs *crs, int num)
iotlb_lock_get(obj, &saved);
for_each_iotlb_cr(obj, num, i, tmp) {
- if (!iotlb_cr_valid(&tmp))
+ if (!iotlb_cr_valid(obj, &tmp))
continue;
*p++ = tmp;
}
@@ -666,7 +632,7 @@ iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e)
break;
}
- prot = get_iopte_attr(e);
+ prot = get_iopte_attr(obj, e);
spin_lock(&obj->page_table_lock);
err = fn(obj, e->da, e->pa, prot);
@@ -873,8 +839,10 @@ static struct omap_iommu *omap_iommu_attach(const char *name, u32 *iopgd)
dev = driver_find_device(&omap_iommu_driver.driver, NULL,
(void *)name,
device_match_by_alias);
- if (!dev)
+ if (!dev) {
+ dev_err(dev, "%s: can't find IOMMU %s\n", __func__, name);
return ERR_PTR(-ENODEV);
+ }
obj = to_iommu(dev);
@@ -894,6 +862,7 @@ static struct omap_iommu *omap_iommu_attach(const char *name, u32 *iopgd)
flush_iotlb_all(obj);
if (!try_module_get(obj->owner)) {
+ dev_err(obj->dev, "%s: can't get owner\n", __func__);
err = -ENODEV;
goto err_module;
}
@@ -969,6 +938,7 @@ static int omap_iommu_probe(struct platform_device *pdev)
obj->dev = &pdev->dev;
obj->ctx = (void *)obj + sizeof(*obj);
+ obj->arch_iommu = &omap2_iommu_ops;
spin_lock_init(&obj->iommu_lock);
spin_lock_init(&obj->page_table_lock);
diff --git a/drivers/iommu/omap-iommu.h b/drivers/iommu/omap-iommu.h
index 1275a82..7a90800 100644
--- a/drivers/iommu/omap-iommu.h
+++ b/drivers/iommu/omap-iommu.h
@@ -46,6 +46,9 @@ struct omap_iommu {
int nr_tlb_entries;
+ /* accommodate the difference between omap1 and omap2/3 */
+ const struct iommu_functions *arch_iommu;
+
void *ctx; /* iommu context: registres saved area */
int has_bus_err_back;
@@ -193,9 +196,10 @@ static inline struct omap_iommu *dev_to_omap_iommu(struct device *dev)
/*
* global functions
*/
-extern u32 omap_iommu_arch_version(void);
+extern u32 omap_iommu_arch_version(struct omap_iommu *obj);
-extern void omap_iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e);
+extern void omap_iotlb_cr_to_e(struct omap_iommu *obj, struct cr_regs *cr,
+ struct iotlb_entry *e);
extern int
omap_iopgtable_store_entry(struct omap_iommu *obj, struct iotlb_entry *e);
@@ -214,6 +218,8 @@ omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t len);
extern size_t
omap_dump_tlb_entries(struct omap_iommu *obj, char *buf, ssize_t len);
+extern const struct iommu_functions omap2_iommu_ops;
+
/*
* register accessors
*/
diff --git a/drivers/iommu/omap-iommu2.c b/drivers/iommu/omap-iommu2.c
index 5e1ea3b..e72fe62 100644
--- a/drivers/iommu/omap-iommu2.c
+++ b/drivers/iommu/omap-iommu2.c
@@ -296,7 +296,7 @@ static void omap2_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
e->mixed = cr->ram & MMU_RAM_MIXED;
}
-static const struct iommu_functions omap2_iommu_ops = {
+const struct iommu_functions omap2_iommu_ops = {
.version = IOMMU_ARCH_VERSION,
.enable = omap2_iommu_enable,
@@ -319,19 +319,3 @@ static const struct iommu_functions omap2_iommu_ops = {
.restore_ctx = omap2_iommu_restore_ctx,
.dump_ctx = omap2_iommu_dump_ctx,
};
-
-static int __init omap2_iommu_init(void)
-{
- return omap_install_iommu_arch(&omap2_iommu_ops);
-}
-module_init(omap2_iommu_init);
-
-static void __exit omap2_iommu_exit(void)
-{
- omap_uninstall_iommu_arch(&omap2_iommu_ops);
-}
-module_exit(omap2_iommu_exit);
-
-MODULE_AUTHOR("Hiroshi DOYU, Paul Mundt and Toshihiro Kobayashi");
-MODULE_DESCRIPTION("omap iommu: omap2/3 architecture specific functions");
-MODULE_LICENSE("GPL v2");
--
1.8.5.5
--
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