diff mbox series

[3/7] iommu/ipmmu-vmsa: Prepare to handle 40-bit error addresses

Message ID 20190220150531.2462-4-geert+renesas@glider.be (mailing list archive)
State Superseded
Delegated to: Geert Uytterhoeven
Headers show
Series iommu/ipmmu-vmsa: Suspend/resume support and assorted cleanups | expand

Commit Message

Geert Uytterhoeven Feb. 20, 2019, 3:05 p.m. UTC 
On R-Car Gen3, the faulting virtual address is a 40-bit address, and
comprised of two registers.  Read the upper address part, and combine
both parts, when running on a 64-bit system.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Apart from this, the driver doesn't support 40-bit IOVA addresses yet.
---
 drivers/iommu/ipmmu-vmsa.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

Comments

Laurent Pinchart Feb. 20, 2019, 3:30 p.m. UTC | #1 
Hi Geert,

Thank you for the patch.

On Wed, Feb 20, 2019 at 04:05:27PM +0100, Geert Uytterhoeven wrote:
> On R-Car Gen3, the faulting virtual address is a 40-bit address, and
> comprised of two registers.  Read the upper address part, and combine
> both parts, when running on a 64-bit system.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> Apart from this, the driver doesn't support 40-bit IOVA addresses yet.
> ---
>  drivers/iommu/ipmmu-vmsa.c | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index ac70cb967ff821c6..4d07c26c97848b65 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -186,7 +186,9 @@ static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
>  #define IMMAIR_ATTR_IDX_WBRWA		1
>  #define IMMAIR_ATTR_IDX_DEV		2
>  
> -#define IMEAR				0x0030
> +#define IMEAR				0x0030	/* R-Car Gen2 */
> +#define IMELAR				IMEAR	/* R-Car Gen3 */

I would have defined that as a single macro.

> +#define IMEUAR				0x0034	/* R-Car Gen3 */
>  
>  #define IMPCTR				0x0200
>  #define IMPSTR				0x0208
> @@ -521,14 +523,16 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
>  {
>  	const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
>  	struct ipmmu_vmsa_device *mmu = domain->mmu;
> +	unsigned long iova;

Isn't there a more appropriate type, such as dma_addr_t possibly ?

>  	u32 status;
> -	u32 iova;
>  
>  	status = ipmmu_ctx_read_root(domain, IMSTR);
>  	if (!(status & err_mask))
>  		return IRQ_NONE;
>  
> -	iova = ipmmu_ctx_read_root(domain, IMEAR);
> +	iova = ipmmu_ctx_read_root(domain, IMELAR);
> +	if (IS_ENABLED(CONFIG_64BIT))
> +		iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32;
>  
>  	/*
>  	 * Clear the error status flags. Unlike traditional interrupt flag
> @@ -540,10 +544,10 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
>  
>  	/* Log fatal errors. */
>  	if (status & IMSTR_MHIT)
> -		dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%08x\n",
> +		dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n",
>  				    iova);
>  	if (status & IMSTR_ABORT)
> -		dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%08x\n",
> +		dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n",
>  				    iova);
>  
>  	if (!(status & (IMSTR_PF | IMSTR_TF)))
> @@ -559,7 +563,7 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
>  		return IRQ_HANDLED;
>  
>  	dev_err_ratelimited(mmu->dev,
> -			    "Unhandled fault: status 0x%08x iova 0x%08x\n",
> +			    "Unhandled fault: status 0x%08x iova 0x%lx\n",
>  			    status, iova);
>  
>  	return IRQ_HANDLED;
Geert Uytterhoeven Feb. 20, 2019, 3:42 p.m. UTC | #2 
Hi Laurent,

On Wed, Feb 20, 2019 at 4:31 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
> On Wed, Feb 20, 2019 at 04:05:27PM +0100, Geert Uytterhoeven wrote:
> > On R-Car Gen3, the faulting virtual address is a 40-bit address, and
> > comprised of two registers.  Read the upper address part, and combine
> > both parts, when running on a 64-bit system.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> > Apart from this, the driver doesn't support 40-bit IOVA addresses yet.
> > ---
> >  drivers/iommu/ipmmu-vmsa.c | 16 ++++++++++------
> >  1 file changed, 10 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> > index ac70cb967ff821c6..4d07c26c97848b65 100644
> > --- a/drivers/iommu/ipmmu-vmsa.c
> > +++ b/drivers/iommu/ipmmu-vmsa.c
> > @@ -186,7 +186,9 @@ static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
> >  #define IMMAIR_ATTR_IDX_WBRWA                1
> >  #define IMMAIR_ATTR_IDX_DEV          2
> >
> > -#define IMEAR                                0x0030
> > +#define IMEAR                                0x0030  /* R-Car Gen2 */
> > +#define IMELAR                               IMEAR   /* R-Car Gen3 */
>
> I would have defined that as a single macro.

Fair enough.

> > +#define IMEUAR                               0x0034  /* R-Car Gen3 */
> >
> >  #define IMPCTR                               0x0200
> >  #define IMPSTR                               0x0208
> > @@ -521,14 +523,16 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
> >  {
> >       const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
> >       struct ipmmu_vmsa_device *mmu = domain->mmu;
> > +     unsigned long iova;
>
> Isn't there a more appropriate type, such as dma_addr_t possibly ?

Good question! Thanks for opening the can of worms ;-)

I used "unsigned long", as that's what the "iova" parameter of
report_iommu_fault() (called in this function) takes.

However, dma_addr_t would probably be a better choice.

Note that most iommu_ops methods take unsigned long, except for
.iova_to_phys(), which takes dma_addr_t.
Also, all io_pgtable_ops methods take unsigned long, including
.iova_to_phys().

The latter is interesting, as several IOMMU drivers forward the iova
received in their iommu_ops.iova_to_phys() methods to
io_pgtable_ops.iova_to_phys(), thus truncating the value on e.g. arm32
with LPAE.

Gr{oetje,eeting}s,

                        Geert
diff mbox series

Patch

diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index ac70cb967ff821c6..4d07c26c97848b65 100644
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -186,7 +186,9 @@  static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
 #define IMMAIR_ATTR_IDX_WBRWA		1
 #define IMMAIR_ATTR_IDX_DEV		2
 
-#define IMEAR				0x0030
+#define IMEAR				0x0030	/* R-Car Gen2 */
+#define IMELAR				IMEAR	/* R-Car Gen3 */
+#define IMEUAR				0x0034	/* R-Car Gen3 */
 
 #define IMPCTR				0x0200
 #define IMPSTR				0x0208
@@ -521,14 +523,16 @@  static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
 {
 	const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
 	struct ipmmu_vmsa_device *mmu = domain->mmu;
+	unsigned long iova;
 	u32 status;
-	u32 iova;
 
 	status = ipmmu_ctx_read_root(domain, IMSTR);
 	if (!(status & err_mask))
 		return IRQ_NONE;
 
-	iova = ipmmu_ctx_read_root(domain, IMEAR);
+	iova = ipmmu_ctx_read_root(domain, IMELAR);
+	if (IS_ENABLED(CONFIG_64BIT))
+		iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32;
 
 	/*
 	 * Clear the error status flags. Unlike traditional interrupt flag
@@ -540,10 +544,10 @@  static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
 
 	/* Log fatal errors. */
 	if (status & IMSTR_MHIT)
-		dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%08x\n",
+		dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n",
 				    iova);
 	if (status & IMSTR_ABORT)
-		dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%08x\n",
+		dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n",
 				    iova);
 
 	if (!(status & (IMSTR_PF | IMSTR_TF)))
@@ -559,7 +563,7 @@  static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
 		return IRQ_HANDLED;
 
 	dev_err_ratelimited(mmu->dev,
-			    "Unhandled fault: status 0x%08x iova 0x%08x\n",
+			    "Unhandled fault: status 0x%08x iova 0x%lx\n",
 			    status, iova);
 
 	return IRQ_HANDLED;