[PATCH 1/2] iommu/arm-smmu-v3: constify arm_smmu_options[]

[PATCH 1/2] iommu/arm-smmu-v3: constify arm_smmu_options[]

[Masahiro Yamada]

This is a read-only array.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---

 drivers/iommu/arm-smmu-v3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index b463599559d2..ed9933960370 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -673,7 +673,7 @@ struct arm_smmu_option_prop {
 	const char *prop;
 };
 
-static struct arm_smmu_option_prop arm_smmu_options[] = {
+static const struct arm_smmu_option_prop arm_smmu_options[] = {
 	{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
 	{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
 	{ 0, NULL},
-- 
2.17.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

[PATCH 2/2] iommu/arm-smmu-v3: simplify parse_driver_options()

[Masahiro Yamada]

Using ARRAY_SIZE() instead of the sentinel is slightly simpler, IMHO.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---

 drivers/iommu/arm-smmu-v3.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index ed9933960370..b27489b7f9d8 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -676,7 +676,6 @@ struct arm_smmu_option_prop {
 static const struct arm_smmu_option_prop arm_smmu_options[] = {
 	{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
 	{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
-	{ 0, NULL},
 };
 
 static inline void __iomem *arm_smmu_page1_fixup(unsigned long offset,
@@ -696,16 +695,16 @@ static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom)
 
 static void parse_driver_options(struct arm_smmu_device *smmu)
 {
-	int i = 0;
+	int i;
 
-	do {
+	for (i = 0; i < ARRAY_SIZE(arm_smmu_options); i++) {
 		if (of_property_read_bool(smmu->dev->of_node,
 						arm_smmu_options[i].prop)) {
 			smmu->options |= arm_smmu_options[i].opt;
 			dev_notice(smmu->dev, "option %s\n",
 				arm_smmu_options[i].prop);
 		}
-	} while (arm_smmu_options[++i].opt);
+	};
 }
 
 /* Low-level queue manipulation functions */
-- 
2.17.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

Re: [PATCH 2/2] iommu/arm-smmu-v3: simplify parse_driver_options()

[Robin Murphy]

On 26/12/2019 9:51 am, Masahiro Yamada wrote:
> Using ARRAY_SIZE() instead of the sentinel is slightly simpler, IMHO.

Given that it's fairly well-decided that we don't want to add any more 
of these anyway, I'd be inclined to lose the array/loop machinery 
altogether. As it is we'd need a lot more options for it to actually 
offer any kind of code size saving.

Robin.

> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---
> 
>   drivers/iommu/arm-smmu-v3.c | 7 +++----
>   1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
> index ed9933960370..b27489b7f9d8 100644
> --- a/drivers/iommu/arm-smmu-v3.c
> +++ b/drivers/iommu/arm-smmu-v3.c
> @@ -676,7 +676,6 @@ struct arm_smmu_option_prop {
>   static const struct arm_smmu_option_prop arm_smmu_options[] = {
>   	{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
>   	{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
> -	{ 0, NULL},
>   };
>   
>   static inline void __iomem *arm_smmu_page1_fixup(unsigned long offset,
> @@ -696,16 +695,16 @@ static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom)
>   
>   static void parse_driver_options(struct arm_smmu_device *smmu)
>   {
> -	int i = 0;
> +	int i;
>   
> -	do {
> +	for (i = 0; i < ARRAY_SIZE(arm_smmu_options); i++) {
>   		if (of_property_read_bool(smmu->dev->of_node,
>   						arm_smmu_options[i].prop)) {
>   			smmu->options |= arm_smmu_options[i].opt;
>   			dev_notice(smmu->dev, "option %s\n",
>   				arm_smmu_options[i].prop);
>   		}
> -	} while (arm_smmu_options[++i].opt);
> +	};
>   }
>   
>   /* Low-level queue manipulation functions */
> 
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu