Add support to register an isr for IOMMU fault situations and adapt it
to allow such (*isr)() to be used as fault callback. Drivers using IOMMU
module might want to be informed when errors happen in order to debug it
or react.
Signed-off-by: David Cohen <dacohen@xxxxxxxxx>
---
arch/arm/mach-omap2/iommu2.c | 17 +++++++++-
arch/arm/plat-omap/include/plat/iommu.h | 14 ++++++++-
arch/arm/plat-omap/iommu.c | 52 ++++++++++++++++++++++---------
3 files changed, 65 insertions(+), 18 deletions(-)
diff --git a/arch/arm/mach-omap2/iommu2.c b/arch/arm/mach-omap2/iommu2.c
index 49a1e5e..adb083e 100644
--- a/arch/arm/mach-omap2/iommu2.c
+++ b/arch/arm/mach-omap2/iommu2.c
@@ -146,18 +146,31 @@ static void omap2_iommu_set_twl(struct iommu *obj, bool on)
static u32 omap2_iommu_fault_isr(struct iommu *obj, u32 *ra)
{
u32 stat, da;
+ u32 errs = 0;
stat = iommu_read_reg(obj, MMU_IRQSTATUS);
stat &= MMU_IRQ_MASK;
- if (!stat)
+ if (!stat) {
+ *ra = 0;
return 0;
+ }
da = iommu_read_reg(obj, MMU_FAULT_AD);
*ra = da;
+ if (stat & MMU_IRQ_TLBMISS)
+ errs |= OMAP_IOMMU_ERR_TLB_MISS;
+ if (stat & MMU_IRQ_TRANSLATIONFAULT)
+ errs |= OMAP_IOMMU_ERR_TRANS_FAULT;
+ if (stat & MMU_IRQ_EMUMISS)
+ errs |= OMAP_IOMMU_ERR_EMU_MISS;
+ if (stat & MMU_IRQ_TABLEWALKFAULT)
+ errs |= OMAP_IOMMU_ERR_TBLWALK_FAULT;
+ if (stat & MMU_IRQ_MULTIHITFAULT)
+ errs |= OMAP_IOMMU_ERR_MULTIHIT_FAULT;
iommu_write_reg(obj, stat, MMU_IRQSTATUS);
- return stat;
+ return errs;
}
static void omap2_tlb_read_cr(struct iommu *obj, struct cr_regs *cr)
diff --git a/arch/arm/plat-omap/include/plat/iommu.h b/arch/arm/plat-omap/include/plat/iommu.h
index 19cbb5e..174f1b9 100644
--- a/arch/arm/plat-omap/include/plat/iommu.h
+++ b/arch/arm/plat-omap/include/plat/iommu.h
@@ -31,6 +31,7 @@ struct iommu {
struct clk *clk;
void __iomem *regbase;
struct device *dev;
+ void *isr_priv;
unsigned int refcount;
struct mutex iommu_lock; /* global for this whole object */
@@ -47,7 +48,7 @@ struct iommu {
struct list_head mmap;
struct mutex mmap_lock; /* protect mmap */
- int (*isr)(struct iommu *obj);
+ int (*isr)(struct iommu *obj, u32 da, u32 iommu_errs, void *priv);
void *ctx; /* iommu context: registres saved area */
u32 da_start;
@@ -109,6 +110,13 @@ struct iommu_platform_data {
u32 da_end;
};
+/* IOMMU errors */
+#define OMAP_IOMMU_ERR_TLB_MISS (1 << 0)
+#define OMAP_IOMMU_ERR_TRANS_FAULT (1 << 1)
+#define OMAP_IOMMU_ERR_EMU_MISS (1 << 2)
+#define OMAP_IOMMU_ERR_TBLWALK_FAULT (1 << 3)
+#define OMAP_IOMMU_ERR_MULTIHIT_FAULT (1 << 4)
+
#if defined(CONFIG_ARCH_OMAP1)
#error "iommu for this processor not implemented yet"
#else
@@ -161,6 +169,10 @@ extern size_t iopgtable_clear_entry(struct iommu *obj, u32 iova);
extern int iommu_set_da_range(struct iommu *obj, u32 start, u32 end);
extern struct iommu *iommu_get(const char *name);
extern void iommu_put(struct iommu *obj);
+extern int iommu_set_isr(const char *name,
+ int (*isr)(struct iommu *obj, u32 da, u32 iommu_errs,
+ void *priv),
+ void *isr_priv);
extern void iommu_save_ctx(struct iommu *obj);
extern void iommu_restore_ctx(struct iommu *obj);
diff --git a/arch/arm/plat-omap/iommu.c b/arch/arm/plat-omap/iommu.c
index f55f458..b0e0efc 100644
--- a/arch/arm/plat-omap/iommu.c
+++ b/arch/arm/plat-omap/iommu.c
@@ -780,25 +780,19 @@ static void iopgtable_clear_entry_all(struct iommu *obj)
*/
static irqreturn_t iommu_fault_handler(int irq, void *data)
{
- u32 stat, da;
+ u32 da, errs;
u32 *iopgd, *iopte;
- int err = -EIO;
struct iommu *obj = data;
if (!obj->refcount)
return IRQ_NONE;
- /* Dynamic loading TLB or PTE */
- if (obj->isr)
- err = obj->isr(obj);
-
- if (!err)
- return IRQ_HANDLED;
-
clk_enable(obj->clk);
- stat = iommu_report_fault(obj, &da);
+ errs = iommu_report_fault(obj, &da);
clk_disable(obj->clk);
- if (!stat)
+
+ /* Fault callback or TLB/PTE Dynamic loading */
+ if (obj->isr && !obj->isr(obj, da, errs, obj->isr_priv))
return IRQ_HANDLED;
iommu_disable(obj);
@@ -806,15 +800,16 @@ static irqreturn_t iommu_fault_handler(int irq, void *data)
iopgd = iopgd_offset(obj, da);
if (!iopgd_is_table(*iopgd)) {
- dev_err(obj->dev, "%s: da:%08x pgd:%p *pgd:%08x\n", obj->name,
- da, iopgd, *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: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n",
- obj->name, da, iopgd, *iopgd, iopte, *iopte);
+ 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;
}
@@ -917,6 +912,33 @@ void iommu_put(struct iommu *obj)
}
EXPORT_SYMBOL_GPL(iommu_put);
+int iommu_set_isr(const char *name,
+ int (*isr)(struct iommu *obj, u32 da, u32 iommu_errs,
+ void *priv),
+ void *isr_priv)
+{
+ struct device *dev;
+ struct iommu *obj;
+
+ dev = driver_find_device(&omap_iommu_driver.driver, NULL, (void *)name,
+ device_match_by_alias);
+ if (!dev)
+ return -ENODEV;
+
+ obj = to_iommu(dev);
+ mutex_lock(&obj->iommu_lock);
+ if (obj->refcount != 0) {
+ mutex_unlock(&obj->iommu_lock);
+ return -EBUSY;
+ }
+ obj->isr = isr;
+ obj->isr_priv = isr_priv;
+ mutex_unlock(&obj->iommu_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_set_isr);
+
/*
* OMAP Device MMU(IOMMU) detection
*/
--
1.7.2.3
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