diff mbox series

[PATCHv9,3/8] iommu/arm-smmu: Move non-strict mode to use io_pgtable_domain_attr

Message ID 47f8e9760a7fba8b58ea89c9add96f5615f97014.1606150259.git.saiprakash.ranjan@codeaurora.org
State Superseded
Headers show
Series System Cache support for GPU and required SMMU support | expand

Commit Message

Sai Prakash Ranjan Nov. 23, 2020, 5:05 p.m. UTC
Now that we have a struct io_pgtable_domain_attr with quirks,
use that for non_strict mode as well thereby removing the need
for more members of arm_smmu_domain in the future.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
---
 drivers/iommu/arm/arm-smmu/arm-smmu.c | 8 +++-----
 drivers/iommu/arm/arm-smmu/arm-smmu.h | 1 -
 2 files changed, 3 insertions(+), 6 deletions(-)

Comments

Sai Prakash Ranjan Nov. 25, 2020, 5:36 a.m. UTC | #1
On 2020-11-25 03:09, Will Deacon wrote:
> On Mon, Nov 23, 2020 at 10:35:56PM +0530, Sai Prakash Ranjan wrote:

>> Now that we have a struct io_pgtable_domain_attr with quirks,

>> use that for non_strict mode as well thereby removing the need

>> for more members of arm_smmu_domain in the future.

>> 

>> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>

>> ---

>>  drivers/iommu/arm/arm-smmu/arm-smmu.c | 8 +++-----

>>  drivers/iommu/arm/arm-smmu/arm-smmu.h | 1 -

>>  2 files changed, 3 insertions(+), 6 deletions(-)

>> 

>> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c 

>> b/drivers/iommu/arm/arm-smmu/arm-smmu.c

>> index 4b9b10fe50ed..f56f266ebdf7 100644

>> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c

>> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c

>> @@ -786,9 +786,6 @@ static int arm_smmu_init_domain_context(struct 

>> iommu_domain *domain,

>>  			goto out_clear_smmu;

>>  	}

>> 

>> -	if (smmu_domain->non_strict)

>> -		pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT;

>> -

>>  	if (smmu_domain->pgtbl_cfg.quirks)

>>  		pgtbl_cfg.quirks |= smmu_domain->pgtbl_cfg.quirks;

>> 

>> @@ -1527,7 +1524,8 @@ static int arm_smmu_domain_get_attr(struct 

>> iommu_domain *domain,

>>  	case IOMMU_DOMAIN_DMA:

>>  		switch (attr) {

>>  		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:

>> -			*(int *)data = smmu_domain->non_strict;

>> +			if (smmu_domain->pgtbl_cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT)

>> +				*(int *)data = smmu_domain->pgtbl_cfg.quirks;

> 

> I still don't think this is right :(

> We need to set *data to 1 or 0 depending on whether or not the 

> non-strict

> quirk is set, i.e:

> 

> 	bool non_strict = smmu_domain->pgtbl_cfg.quirks & 

> IO_PGTABLE_QUIRK_NON_STRICT;

> 	*(int *)data = non_strict;

> 

> Your code above leaves *data uninitialised if non_strict is not set.


Ugh sorry, I should have looked at this some more before hurrying up
to post, will fix it.

> 

>>  			return 0;

>>  		default:

>>  			return -ENODEV;

>> @@ -1578,7 +1576,7 @@ static int arm_smmu_domain_set_attr(struct 

>> iommu_domain *domain,

>>  	case IOMMU_DOMAIN_DMA:

>>  		switch (attr) {

>>  		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:

>> -			smmu_domain->non_strict = *(int *)data;

>> +			smmu_domain->pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT;

> 

> And this is broken because if *data is 0, then you _set_ the quirk, 

> which is

> the opposite of what we should be doing.

> 

> In other words, although the implementation has changed, the semantics 

> have

> not.

> 


Will fix this to have quirk set only when *data = 1 and unset in case of 
0.

Thanks,
Sai

-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a 
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diff mbox series

Patch

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 4b9b10fe50ed..f56f266ebdf7 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -786,9 +786,6 @@  static int arm_smmu_init_domain_context(struct iommu_domain *domain,
 			goto out_clear_smmu;
 	}
 
-	if (smmu_domain->non_strict)
-		pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT;
-
 	if (smmu_domain->pgtbl_cfg.quirks)
 		pgtbl_cfg.quirks |= smmu_domain->pgtbl_cfg.quirks;
 
@@ -1527,7 +1524,8 @@  static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
 	case IOMMU_DOMAIN_DMA:
 		switch (attr) {
 		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:
-			*(int *)data = smmu_domain->non_strict;
+			if (smmu_domain->pgtbl_cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT)
+				*(int *)data = smmu_domain->pgtbl_cfg.quirks;
 			return 0;
 		default:
 			return -ENODEV;
@@ -1578,7 +1576,7 @@  static int arm_smmu_domain_set_attr(struct iommu_domain *domain,
 	case IOMMU_DOMAIN_DMA:
 		switch (attr) {
 		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:
-			smmu_domain->non_strict = *(int *)data;
+			smmu_domain->pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT;
 			break;
 		default:
 			ret = -ENODEV;
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.h b/drivers/iommu/arm/arm-smmu/arm-smmu.h
index bb5a419f240f..cb7ca3a444c9 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.h
@@ -368,7 +368,6 @@  struct arm_smmu_domain {
 	const struct iommu_flush_ops	*flush_ops;
 	struct arm_smmu_cfg		cfg;
 	enum arm_smmu_domain_stage	stage;
-	bool				non_strict;
 	struct mutex			init_mutex; /* Protects smmu pointer */
 	spinlock_t			cb_lock; /* Serialises ATS1* ops and TLB syncs */
 	struct iommu_domain		domain;