[PATCH v6 02/12] iommu/exynos: always use iommu fault handler
Cho KyongHo
pullip.cho at samsung.com
Tue Dec 25 20:53:29 EST 2012
This commit removes fault handler definition only for exynos-iommu
driver. Instead, always call iommu fault handler when a fault is
generated by a System MMU. Every new iommu_domain will have a default
fault handler and it can be overridden with iommu_set_fault_handler().
The default fault handler also generates debugging messages and kernel
woops.
Signed-off-by: KyongHo Cho <pullip.cho at samsung.com>
---
drivers/iommu/exynos-iommu.c | 99 ++++++++++++++++----------------------------
1 file changed, 36 insertions(+), 63 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index b96f3b9..ef7dbd1 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -124,16 +124,6 @@ enum exynos_sysmmu_inttype {
SYSMMU_FAULTS_NUM
};
-/*
- * @itype: type of fault.
- * @pgtable_base: the physical address of page table base. This is 0 if @itype
- * is SYSMMU_BUSERROR.
- * @fault_addr: the device (virtual) address that the System MMU tried to
- * translated. This is 0 if @itype is SYSMMU_BUSERROR.
- */
-typedef int (*sysmmu_fault_handler_t)(enum exynos_sysmmu_inttype itype,
- unsigned long pgtable_base, unsigned long fault_addr);
-
static unsigned short fault_reg_offset[SYSMMU_FAULTS_NUM] = {
REG_PAGE_FAULT_ADDR,
REG_AR_FAULT_ADDR,
@@ -176,7 +166,6 @@ struct sysmmu_drvdata {
int activations;
rwlock_t lock;
struct iommu_domain *domain;
- sysmmu_fault_handler_t fault_handler;
unsigned long pgtable;
};
@@ -291,48 +280,23 @@ finish:
read_unlock_irqrestore(&data->lock, flags);
}
-static void __set_fault_handler(struct sysmmu_drvdata *data,
- sysmmu_fault_handler_t handler)
-{
- unsigned long flags;
-
- write_lock_irqsave(&data->lock, flags);
- data->fault_handler = handler;
- write_unlock_irqrestore(&data->lock, flags);
-}
-
-void exynos_sysmmu_set_fault_handler(struct device *dev,
- sysmmu_fault_handler_t handler)
-{
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
-
- __set_fault_handler(data, handler);
-}
-
-static int default_fault_handler(enum exynos_sysmmu_inttype itype,
- unsigned long pgtable_base, unsigned long fault_addr)
+static void __show_fault_information(unsigned long *pgtable, unsigned long iova,
+ int flags)
{
unsigned long *ent;
- if ((itype >= SYSMMU_FAULTS_NUM) || (itype < SYSMMU_PAGEFAULT))
- itype = SYSMMU_FAULT_UNKNOWN;
-
pr_err("%s occurred at 0x%lx(Page table base: 0x%lx)\n",
- sysmmu_fault_name[itype], fault_addr, pgtable_base);
+ sysmmu_fault_name[flags], iova, __pa(pgtable));
- ent = section_entry(__va(pgtable_base), fault_addr);
+ ent = section_entry(pgtable, iova);
pr_err("\tLv1 entry: 0x%lx\n", *ent);
if (lv1ent_page(ent)) {
- ent = page_entry(ent, fault_addr);
+ ent = page_entry(ent, iova);
pr_err("\t Lv2 entry: 0x%lx\n", *ent);
}
pr_err("Generating Kernel OOPS... because it is unrecoverable.\n");
-
- BUG();
-
- return 0;
}
static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
@@ -341,7 +305,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
struct sysmmu_drvdata *data = dev_id;
struct resource *irqres;
struct platform_device *pdev;
- enum exynos_sysmmu_inttype itype;
+ enum exynos_sysmmu_inttype itype = SYSMMU_FAULT_UNKNOWN;
unsigned long addr = -1;
int i, ret = -ENOSYS;
@@ -357,9 +321,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
break;
}
- if (i == pdev->num_resources) {
- itype = SYSMMU_FAULT_UNKNOWN;
- } else {
+ if (i < pdev->num_resources) {
itype = (enum exynos_sysmmu_inttype)
__ffs(__raw_readl(data->sfrbases[i] + REG_INT_STATUS));
if (WARN_ON(!((itype >= 0) && (itype < SYSMMU_FAULT_UNKNOWN))))
@@ -370,25 +332,25 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
}
if (data->domain)
- ret = report_iommu_fault(data->domain, data->dev,
- addr, itype);
-
- if ((ret == -ENOSYS) && data->fault_handler) {
- unsigned long base = data->pgtable;
- if (itype != SYSMMU_FAULT_UNKNOWN)
- base = __raw_readl(
- data->sfrbases[i] + REG_PT_BASE_ADDR);
- ret = data->fault_handler(itype, base, addr);
- }
-
- if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
+ ret = report_iommu_fault(data->domain, data->dev, addr, itype);
+ else
+ __show_fault_information(__va(data->pgtable), itype, addr);
+
+ if (ret == -ENOSYS)
+ pr_err("NO SYSTEM MMU FAULT HANDLER REGISTERED FOR %s\n",
+ dev_name(data->dev));
+ else if (ret < 0)
+ pr_err("SYSTEM MMU FAULT HANDLER FOR %s RETURNED ERROR, %d\n",
+ dev_name(data->dev), ret);
+ else if (itype != SYSMMU_FAULT_UNKNOWN)
__raw_writel(1 << itype, data->sfrbases[i] + REG_INT_CLEAR);
else
- dev_dbg(data->sysmmu, "(%s) %s is not handled.\n",
- data->dbgname, sysmmu_fault_name[itype]);
+ ret = -ENOSYS;
- if (itype != SYSMMU_FAULT_UNKNOWN)
- sysmmu_unblock(data->sfrbases[i]);
+ if (ret)
+ BUG();
+
+ sysmmu_unblock(data->sfrbases[i]);
read_unlock(&data->lock);
@@ -668,8 +630,6 @@ static int exynos_sysmmu_probe(struct platform_device *pdev)
rwlock_init(&data->lock);
INIT_LIST_HEAD(&data->node);
- __set_fault_handler(data, &default_fault_handler);
-
if (dev->parent)
pm_runtime_enable(dev);
@@ -708,6 +668,17 @@ static inline void pgtable_flush(void *vastart, void *vaend)
virt_to_phys(vaend));
}
+static int exynos_iommu_fault_handler(struct iommu_domain *domain,
+ struct device *dev, unsigned long iova, int flags, void *token)
+{
+ struct exynos_iommu_domain *priv = domain->priv;
+
+ dev_err(dev, "System MMU Generated FAULT!\n\n");
+ __show_fault_information(priv->pgtable, iova, flags);
+
+ return -ENOSYS;
+}
+
static int exynos_iommu_domain_init(struct iommu_domain *domain)
{
struct exynos_iommu_domain *priv;
@@ -736,6 +707,8 @@ static int exynos_iommu_domain_init(struct iommu_domain *domain)
domain->geometry.aperture_end = ~0UL;
domain->geometry.force_aperture = true;
+ iommu_set_fault_handler(domain, &exynos_iommu_fault_handler, NULL);
+
domain->priv = priv;
return 0;
--
1.8.0
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