Commit d594f1f3 authored by David Cohen's avatar David Cohen Committed by Tony Lindgren
Browse files

omap: IOMMU: add support to callback during fault handling 



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: default avatarDavid Cohen <dacohen@gmail.com>
Acked-by: default avatarHiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
parent 92e753d7

arch/arm/mach-omap2/iommu2.c

+15 −2
Original line number Diff line number Diff line
@@ -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)

arch/arm/plat-omap/include/plat/iommu.h

+13 −1
Original line number Diff line number Diff line
@@ -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);

arch/arm/plat-omap/iommu.c

+37 −15
Original line number Diff line number Diff line
@@ -783,25 +783,19 @@ 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);
@@ -809,15 +803,16 @@ 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;

}
@@ -920,6 +915,33 @@ 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

 */

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