[1/9] iommu/of: Drop early initialisation hooks

Message ID 20180111082229.24011-2-jeffy.chen@rock-chips.com
State Changes Requested
Headers show
Series
  • iommu/rockchip: Use OF_IOMMU
Related show

Commit Message

JeffyChen Jan. 11, 2018, 8:22 a.m.
With the probe-deferral mechanism, early initialisation hooks are no
longer needed.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
---

 drivers/iommu/arm-smmu-v3.c  |  2 +-
 drivers/iommu/arm-smmu.c     | 12 ++++++------
 drivers/iommu/exynos-iommu.c |  2 +-
 drivers/iommu/ipmmu-vmsa.c   | 17 ++---------------
 drivers/iommu/msm_iommu.c    | 24 +++++++-----------------
 drivers/iommu/of_iommu.c     | 16 ----------------
 drivers/iommu/qcom_iommu.c   |  2 +-
 include/linux/of_iommu.h     |  6 ++----
 8 files changed, 20 insertions(+), 61 deletions(-)

Comments

Marek Szyprowski Jan. 11, 2018, 9:40 a.m. | #1
Hi Jeffy,

On 2018-01-11 09:22, Jeffy Chen wrote:
> With the probe-deferral mechanism, early initialisation hooks are no
> longer needed.
>
> Suggested-by: Robin Murphy <robin.murphy@arm.com>
> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> ---
>
>   drivers/iommu/arm-smmu-v3.c  |  2 +-
>   drivers/iommu/arm-smmu.c     | 12 ++++++------
>   drivers/iommu/exynos-iommu.c |  2 +-

For Exynos IOMMU:
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>

IPMMU and MSM IOMMU are no longer multi-platform safe after this patch.
It breaks them in the same way as my commit 928055a01b3f ("iommu/exynos:
Remove custom platform device registration code") broke Exynos IOMMU.

You need a similar fix for them:
https://www.spinics.net/lists/arm-kernel/msg627648.html

>   drivers/iommu/ipmmu-vmsa.c   | 17 ++---------------
>   drivers/iommu/msm_iommu.c    | 24 +++++++-----------------
>   drivers/iommu/of_iommu.c     | 16 ----------------
>   drivers/iommu/qcom_iommu.c   |  2 +-
>   include/linux/of_iommu.h     |  6 ++----
>   8 files changed, 20 insertions(+), 61 deletions(-)
>
> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
> index 744592d330ca..3f2f1fc68b52 100644
> --- a/drivers/iommu/arm-smmu-v3.c
> +++ b/drivers/iommu/arm-smmu-v3.c
> @@ -2971,7 +2971,7 @@ static struct platform_driver arm_smmu_driver = {
>   };
>   module_platform_driver(arm_smmu_driver);
>   
> -IOMMU_OF_DECLARE(arm_smmuv3, "arm,smmu-v3", NULL);
> +IOMMU_OF_DECLARE(arm_smmuv3, "arm,smmu-v3");
>   
>   MODULE_DESCRIPTION("IOMMU API for ARM architected SMMUv3 implementations");
>   MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 78d4c6b8f1ba..69e7c60792a8 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -2211,12 +2211,12 @@ static struct platform_driver arm_smmu_driver = {
>   };
>   module_platform_driver(arm_smmu_driver);
>   
> -IOMMU_OF_DECLARE(arm_smmuv1, "arm,smmu-v1", NULL);
> -IOMMU_OF_DECLARE(arm_smmuv2, "arm,smmu-v2", NULL);
> -IOMMU_OF_DECLARE(arm_mmu400, "arm,mmu-400", NULL);
> -IOMMU_OF_DECLARE(arm_mmu401, "arm,mmu-401", NULL);
> -IOMMU_OF_DECLARE(arm_mmu500, "arm,mmu-500", NULL);
> -IOMMU_OF_DECLARE(cavium_smmuv2, "cavium,smmu-v2", NULL);
> +IOMMU_OF_DECLARE(arm_smmuv1, "arm,smmu-v1");
> +IOMMU_OF_DECLARE(arm_smmuv2, "arm,smmu-v2");
> +IOMMU_OF_DECLARE(arm_mmu400, "arm,mmu-400");
> +IOMMU_OF_DECLARE(arm_mmu401, "arm,mmu-401");
> +IOMMU_OF_DECLARE(arm_mmu500, "arm,mmu-500");
> +IOMMU_OF_DECLARE(cavium_smmuv2, "cavium,smmu-v2");
>   
>   MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations");
>   MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index 79c45650f8de..1c7f926fad0e 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -1394,4 +1394,4 @@ static int __init exynos_iommu_init(void)
>   }
>   core_initcall(exynos_iommu_init);
>   
> -IOMMU_OF_DECLARE(exynos_iommu_of, "samsung,exynos-sysmmu", NULL);
> +IOMMU_OF_DECLARE(exynos_iommu_of, "samsung,exynos-sysmmu");
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index 8dce3a9de9d8..07b711bb4b16 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -1081,12 +1081,8 @@ static struct platform_driver ipmmu_driver = {
>   
>   static int __init ipmmu_init(void)
>   {
> -	static bool setup_done;
>   	int ret;
>   
> -	if (setup_done)
> -		return 0;
> -
>   	ret = platform_driver_register(&ipmmu_driver);
>   	if (ret < 0)
>   		return ret;
> @@ -1096,7 +1092,6 @@ static int __init ipmmu_init(void)
>   		bus_set_iommu(&platform_bus_type, &ipmmu_ops);
>   #endif
>   
> -	setup_done = true;
>   	return 0;
>   }
>   
> @@ -1109,16 +1104,8 @@ subsys_initcall(ipmmu_init);
>   module_exit(ipmmu_exit);
>   
>   #ifdef CONFIG_IOMMU_DMA
> -static int __init ipmmu_vmsa_iommu_of_setup(struct device_node *np)
> -{
> -	ipmmu_init();
> -	return 0;
> -}
> -
> -IOMMU_OF_DECLARE(ipmmu_vmsa_iommu_of, "renesas,ipmmu-vmsa",
> -		 ipmmu_vmsa_iommu_of_setup);
> -IOMMU_OF_DECLARE(ipmmu_r8a7795_iommu_of, "renesas,ipmmu-r8a7795",
> -		 ipmmu_vmsa_iommu_of_setup);
> +IOMMU_OF_DECLARE(ipmmu_vmsa_iommu_of, "renesas,ipmmu-vmsa");
> +IOMMU_OF_DECLARE(ipmmu_r8a7795_iommu_of, "renesas,ipmmu-r8a7795");
>   #endif
>   
>   MODULE_DESCRIPTION("IOMMU API for Renesas VMSA-compatible IPMMU");
> diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
> index 04f4d51ffacb..a41d4251b0a9 100644
> --- a/drivers/iommu/msm_iommu.c
> +++ b/drivers/iommu/msm_iommu.c
> @@ -856,7 +856,7 @@ static struct platform_driver msm_iommu_driver = {
>   	.remove		= msm_iommu_remove,
>   };
>   
> -static int __init msm_iommu_driver_init(void)
> +static int __init msm_iommu_init(void)
>   {
>   	int ret;
>   
> @@ -864,30 +864,20 @@ static int __init msm_iommu_driver_init(void)
>   	if (ret != 0)
>   		pr_err("Failed to register IOMMU driver\n");
>   
> +	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
> +
>   	return ret;
>   }
>   
> -static void __exit msm_iommu_driver_exit(void)
> +static void __exit msm_iommu_exit(void)
>   {
>   	platform_driver_unregister(&msm_iommu_driver);
>   }
>   
> -subsys_initcall(msm_iommu_driver_init);
> -module_exit(msm_iommu_driver_exit);
> -
> -static int __init msm_iommu_init(void)
> -{
> -	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
> -	return 0;
> -}
> -
> -static int __init msm_iommu_of_setup(struct device_node *np)
> -{
> -	msm_iommu_init();
> -	return 0;
> -}
> +subsys_initcall(msm_iommu_init);
> +module_exit(msm_iommu_exit);
>   
> -IOMMU_OF_DECLARE(msm_iommu_of, "qcom,apq8064-iommu", msm_iommu_of_setup);
> +IOMMU_OF_DECLARE(msm_iommu_of, "qcom,apq8064-iommu");
>   
>   MODULE_LICENSE("GPL v2");
>   MODULE_AUTHOR("Stepan Moskovchenko <stepanm@codeaurora.org>");
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> index 50947ebb6d17..5c36a8b7656a 100644
> --- a/drivers/iommu/of_iommu.c
> +++ b/drivers/iommu/of_iommu.c
> @@ -231,19 +231,3 @@ const struct iommu_ops *of_iommu_configure(struct device *dev,
>   
>   	return ops;
>   }
> -
> -static int __init of_iommu_init(void)
> -{
> -	struct device_node *np;
> -	const struct of_device_id *match, *matches = &__iommu_of_table;
> -
> -	for_each_matching_node_and_match(np, matches, &match) {
> -		const of_iommu_init_fn init_fn = match->data;
> -
> -		if (init_fn && init_fn(np))
> -			pr_err("Failed to initialise IOMMU %pOF\n", np);
> -	}
> -
> -	return 0;
> -}
> -postcore_initcall_sync(of_iommu_init);
> diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c
> index e07f02d00c68..65b9c99707f8 100644
> --- a/drivers/iommu/qcom_iommu.c
> +++ b/drivers/iommu/qcom_iommu.c
> @@ -947,7 +947,7 @@ static void __exit qcom_iommu_exit(void)
>   module_init(qcom_iommu_init);
>   module_exit(qcom_iommu_exit);
>   
> -IOMMU_OF_DECLARE(qcom_iommu_dev, "qcom,msm-iommu-v1", NULL);
> +IOMMU_OF_DECLARE(qcom_iommu_dev, "qcom,msm-iommu-v1");
>   
>   MODULE_DESCRIPTION("IOMMU API for QCOM IOMMU v1 implementations");
>   MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
> index cddfaff4d0b7..ae03752e8e3a 100644
> --- a/include/linux/of_iommu.h
> +++ b/include/linux/of_iommu.h
> @@ -34,9 +34,7 @@ static inline const struct iommu_ops *of_iommu_configure(struct device *dev,
>   
>   extern struct of_device_id __iommu_of_table;
>   
> -typedef int (*of_iommu_init_fn)(struct device_node *);
> -
> -#define IOMMU_OF_DECLARE(name, compat, fn) \
> -	_OF_DECLARE(iommu, name, compat, fn, of_iommu_init_fn)
> +#define IOMMU_OF_DECLARE(name, compat) \
> +	OF_DECLARE_1(iommu, name, compat, NULL)
>   
>   #endif /* __OF_IOMMU_H */

Best regards
JeffyChen Jan. 11, 2018, 11:14 a.m. | #2
Hi Marek,

Thanks for your reply.

On 01/11/2018 05:40 PM, Marek Szyprowski wrote:
> Hi Jeffy,
>
> On 2018-01-11 09:22, Jeffy Chen wrote:
>> With the probe-deferral mechanism, early initialisation hooks are no
>> longer needed.
>>
>> Suggested-by: Robin Murphy <robin.murphy@arm.com>
>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>> ---
>>
>>   drivers/iommu/arm-smmu-v3.c  |  2 +-
>>   drivers/iommu/arm-smmu.c     | 12 ++++++------
>>   drivers/iommu/exynos-iommu.c |  2 +-
>
> For Exynos IOMMU:
> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
>
> IPMMU and MSM IOMMU are no longer multi-platform safe after this patch.
> It breaks them in the same way as my commit 928055a01b3f ("iommu/exynos:
> Remove custom platform device registration code") broke Exynos IOMMU.
>
> You need a similar fix for them:
> https://www.spinics.net/lists/arm-kernel/msg627648.html

hmmm, right, i did saw this fix in the rockchip iommu driver too.

and there're also some other iommu drivers put bus_set_iommu in their 
probe() to avoid that.

maybe we can do it in the iommu framework?

for example:
1/ add a bus type member to struct iommu_device
2/ and a iommu_device_set_bus()
3/ do the bus_set_iommu stuff in iommu_device_register()
4/ undo bus_set_iommu in iommu_device_unregister()



--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Robin Murphy Jan. 11, 2018, 12:24 p.m. | #3
Hi Jeffy,

On 11/01/18 11:14, JeffyChen wrote:
> Hi Marek,
> 
> Thanks for your reply.
> 
> On 01/11/2018 05:40 PM, Marek Szyprowski wrote:
>> Hi Jeffy,
>>
>> On 2018-01-11 09:22, Jeffy Chen wrote:
>>> With the probe-deferral mechanism, early initialisation hooks are no
>>> longer needed.
>>>
>>> Suggested-by: Robin Murphy <robin.murphy@arm.com>

In fact, shortly after I said that I had a "how hard can it be?" moment 
and took a crack at it myself - sorry, I should probably have cc'd you 
on that series[1].

>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>>> ---
>>>
>>>   drivers/iommu/arm-smmu-v3.c  |  2 +-
>>>   drivers/iommu/arm-smmu.c     | 12 ++++++------
>>>   drivers/iommu/exynos-iommu.c |  2 +-
>>
>> For Exynos IOMMU:
>> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
>>
>> IPMMU and MSM IOMMU are no longer multi-platform safe after this patch.
>> It breaks them in the same way as my commit 928055a01b3f ("iommu/exynos:
>> Remove custom platform device registration code") broke Exynos IOMMU.
>>
>> You need a similar fix for them:
>> https://www.spinics.net/lists/arm-kernel/msg627648.html
> 
> hmmm, right, i did saw this fix in the rockchip iommu driver too.
> 
> and there're also some other iommu drivers put bus_set_iommu in their 
> probe() to avoid that.
> 
> maybe we can do it in the iommu framework?
> 
> for example:
> 1/ add a bus type member to struct iommu_device
> 2/ and a iommu_device_set_bus()
> 3/ do the bus_set_iommu stuff in iommu_device_register()
> 4/ undo bus_set_iommu in iommu_device_unregister()

Ultimately we'd like to get rid of the bus relationship altogether, so I 
don't think it's really worth adding more infrastructure around it. 
Having of-iommu-based drivers set bus ops at probe time, and others 
conditionally from an initcall, is pretty clean and simple, so I'd 
rather stick with that approach for now.

Robin.

[1] 
https://lists.linuxfoundation.org/pipermail/iommu/2018-January/025395.html
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Marek Szyprowski Jan. 11, 2018, 12:26 p.m. | #4
Hi Jeffy,

On 2018-01-11 12:14, JeffyChen wrote:
> Hi Marek,
>
> Thanks for your reply.
>
> On 01/11/2018 05:40 PM, Marek Szyprowski wrote:
>> Hi Jeffy,
>>
>> On 2018-01-11 09:22, Jeffy Chen wrote:
>>> With the probe-deferral mechanism, early initialisation hooks are no
>>> longer needed.
>>>
>>> Suggested-by: Robin Murphy <robin.murphy@arm.com>
>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>>> ---
>>>
>>>   drivers/iommu/arm-smmu-v3.c  |  2 +-
>>>   drivers/iommu/arm-smmu.c     | 12 ++++++------
>>>   drivers/iommu/exynos-iommu.c |  2 +-
>>
>> For Exynos IOMMU:
>> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
>>
>> IPMMU and MSM IOMMU are no longer multi-platform safe after this patch.
>> It breaks them in the same way as my commit 928055a01b3f ("iommu/exynos:
>> Remove custom platform device registration code") broke Exynos IOMMU.
>>
>> You need a similar fix for them:
>> https://www.spinics.net/lists/arm-kernel/msg627648.html
>
> hmmm, right, i did saw this fix in the rockchip iommu driver too.
>
> and there're also some other iommu drivers put bus_set_iommu in their 
> probe() to avoid that.
>
> maybe we can do it in the iommu framework?
>
> for example:
> 1/ add a bus type member to struct iommu_device
> 2/ and a iommu_device_set_bus()
> 3/ do the bus_set_iommu stuff in iommu_device_register()
> 4/ undo bus_set_iommu in iommu_device_unregister()

Frankly, in case the device-tree based systems bus_set_iommu()
should not be needed at all. However for some legacy reasons it
is still required by a few bits of code (at least it was needed
some time ago). Probably it would be best if this is finally
resolved.

Best regards
JeffyChen Jan. 12, 2018, 1:22 a.m. | #5
Hi Robin,

Thnaks for your reply.

On 01/11/2018 08:24 PM, Robin Murphy wrote:
> Hi Jeffy,
>
> On 11/01/18 11:14, JeffyChen wrote:
>> Hi Marek,
>>
>> Thanks for your reply.
>>
>> On 01/11/2018 05:40 PM, Marek Szyprowski wrote:
>>> Hi Jeffy,
>>>
>>> On 2018-01-11 09:22, Jeffy Chen wrote:
>>>> With the probe-deferral mechanism, early initialisation hooks are no
>>>> longer needed.
>>>>
>>>> Suggested-by: Robin Murphy <robin.murphy@arm.com>
>
> In fact, shortly after I said that I had a "how hard can it be?" moment
> and took a crack at it myself - sorry, I should probably have cc'd you
> on that series[1].

hmmm, i'll drop this patch in the next version.

and maybe rebase my patch[9] (iommu/rockchip: Use OF_IOMMU to attach 
devices automatically) on that series
>
>>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>>>> ---
>>>>
>>>>   drivers/iommu/arm-smmu-v3.c  |  2 +-
>>>>   drivers/iommu/arm-smmu.c     | 12 ++++++------
>>>>   drivers/iommu/exynos-iommu.c |  2 +-
>>>
>>> For Exynos IOMMU:
>>> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
>>>
>>> IPMMU and MSM IOMMU are no longer multi-platform safe after this patch.
>>> It breaks them in the same way as my commit 928055a01b3f ("iommu/exynos:
>>> Remove custom platform device registration code") broke Exynos IOMMU.
>>>
>>> You need a similar fix for them:
>>> https://www.spinics.net/lists/arm-kernel/msg627648.html
>>
>> hmmm, right, i did saw this fix in the rockchip iommu driver too.
>>
>> and there're also some other iommu drivers put bus_set_iommu in their
>> probe() to avoid that.
>>
>> maybe we can do it in the iommu framework?
>>
>> for example:
>> 1/ add a bus type member to struct iommu_device
>> 2/ and a iommu_device_set_bus()
>> 3/ do the bus_set_iommu stuff in iommu_device_register()
>> 4/ undo bus_set_iommu in iommu_device_unregister()
>
> Ultimately we'd like to get rid of the bus relationship altogether, so I
> don't think it's really worth adding more infrastructure around it.
> Having of-iommu-based drivers set bus ops at probe time, and others
> conditionally from an initcall, is pretty clean and simple, so I'd
> rather stick with that approach for now.
ok, make sense:)
>
> Robin.
>
> [1]
> https://lists.linuxfoundation.org/pipermail/iommu/2018-January/025395.html
>
>
>


--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 744592d330ca..3f2f1fc68b52 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -2971,7 +2971,7 @@  static struct platform_driver arm_smmu_driver = {
 };
 module_platform_driver(arm_smmu_driver);
 
-IOMMU_OF_DECLARE(arm_smmuv3, "arm,smmu-v3", NULL);
+IOMMU_OF_DECLARE(arm_smmuv3, "arm,smmu-v3");
 
 MODULE_DESCRIPTION("IOMMU API for ARM architected SMMUv3 implementations");
 MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 78d4c6b8f1ba..69e7c60792a8 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -2211,12 +2211,12 @@  static struct platform_driver arm_smmu_driver = {
 };
 module_platform_driver(arm_smmu_driver);
 
-IOMMU_OF_DECLARE(arm_smmuv1, "arm,smmu-v1", NULL);
-IOMMU_OF_DECLARE(arm_smmuv2, "arm,smmu-v2", NULL);
-IOMMU_OF_DECLARE(arm_mmu400, "arm,mmu-400", NULL);
-IOMMU_OF_DECLARE(arm_mmu401, "arm,mmu-401", NULL);
-IOMMU_OF_DECLARE(arm_mmu500, "arm,mmu-500", NULL);
-IOMMU_OF_DECLARE(cavium_smmuv2, "cavium,smmu-v2", NULL);
+IOMMU_OF_DECLARE(arm_smmuv1, "arm,smmu-v1");
+IOMMU_OF_DECLARE(arm_smmuv2, "arm,smmu-v2");
+IOMMU_OF_DECLARE(arm_mmu400, "arm,mmu-400");
+IOMMU_OF_DECLARE(arm_mmu401, "arm,mmu-401");
+IOMMU_OF_DECLARE(arm_mmu500, "arm,mmu-500");
+IOMMU_OF_DECLARE(cavium_smmuv2, "cavium,smmu-v2");
 
 MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations");
 MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 79c45650f8de..1c7f926fad0e 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -1394,4 +1394,4 @@  static int __init exynos_iommu_init(void)
 }
 core_initcall(exynos_iommu_init);
 
-IOMMU_OF_DECLARE(exynos_iommu_of, "samsung,exynos-sysmmu", NULL);
+IOMMU_OF_DECLARE(exynos_iommu_of, "samsung,exynos-sysmmu");
diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index 8dce3a9de9d8..07b711bb4b16 100644
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -1081,12 +1081,8 @@  static struct platform_driver ipmmu_driver = {
 
 static int __init ipmmu_init(void)
 {
-	static bool setup_done;
 	int ret;
 
-	if (setup_done)
-		return 0;
-
 	ret = platform_driver_register(&ipmmu_driver);
 	if (ret < 0)
 		return ret;
@@ -1096,7 +1092,6 @@  static int __init ipmmu_init(void)
 		bus_set_iommu(&platform_bus_type, &ipmmu_ops);
 #endif
 
-	setup_done = true;
 	return 0;
 }
 
@@ -1109,16 +1104,8 @@  subsys_initcall(ipmmu_init);
 module_exit(ipmmu_exit);
 
 #ifdef CONFIG_IOMMU_DMA
-static int __init ipmmu_vmsa_iommu_of_setup(struct device_node *np)
-{
-	ipmmu_init();
-	return 0;
-}
-
-IOMMU_OF_DECLARE(ipmmu_vmsa_iommu_of, "renesas,ipmmu-vmsa",
-		 ipmmu_vmsa_iommu_of_setup);
-IOMMU_OF_DECLARE(ipmmu_r8a7795_iommu_of, "renesas,ipmmu-r8a7795",
-		 ipmmu_vmsa_iommu_of_setup);
+IOMMU_OF_DECLARE(ipmmu_vmsa_iommu_of, "renesas,ipmmu-vmsa");
+IOMMU_OF_DECLARE(ipmmu_r8a7795_iommu_of, "renesas,ipmmu-r8a7795");
 #endif
 
 MODULE_DESCRIPTION("IOMMU API for Renesas VMSA-compatible IPMMU");
diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index 04f4d51ffacb..a41d4251b0a9 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -856,7 +856,7 @@  static struct platform_driver msm_iommu_driver = {
 	.remove		= msm_iommu_remove,
 };
 
-static int __init msm_iommu_driver_init(void)
+static int __init msm_iommu_init(void)
 {
 	int ret;
 
@@ -864,30 +864,20 @@  static int __init msm_iommu_driver_init(void)
 	if (ret != 0)
 		pr_err("Failed to register IOMMU driver\n");
 
+	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
+
 	return ret;
 }
 
-static void __exit msm_iommu_driver_exit(void)
+static void __exit msm_iommu_exit(void)
 {
 	platform_driver_unregister(&msm_iommu_driver);
 }
 
-subsys_initcall(msm_iommu_driver_init);
-module_exit(msm_iommu_driver_exit);
-
-static int __init msm_iommu_init(void)
-{
-	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
-	return 0;
-}
-
-static int __init msm_iommu_of_setup(struct device_node *np)
-{
-	msm_iommu_init();
-	return 0;
-}
+subsys_initcall(msm_iommu_init);
+module_exit(msm_iommu_exit);
 
-IOMMU_OF_DECLARE(msm_iommu_of, "qcom,apq8064-iommu", msm_iommu_of_setup);
+IOMMU_OF_DECLARE(msm_iommu_of, "qcom,apq8064-iommu");
 
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Stepan Moskovchenko <stepanm@codeaurora.org>");
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 50947ebb6d17..5c36a8b7656a 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -231,19 +231,3 @@  const struct iommu_ops *of_iommu_configure(struct device *dev,
 
 	return ops;
 }
-
-static int __init of_iommu_init(void)
-{
-	struct device_node *np;
-	const struct of_device_id *match, *matches = &__iommu_of_table;
-
-	for_each_matching_node_and_match(np, matches, &match) {
-		const of_iommu_init_fn init_fn = match->data;
-
-		if (init_fn && init_fn(np))
-			pr_err("Failed to initialise IOMMU %pOF\n", np);
-	}
-
-	return 0;
-}
-postcore_initcall_sync(of_iommu_init);
diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c
index e07f02d00c68..65b9c99707f8 100644
--- a/drivers/iommu/qcom_iommu.c
+++ b/drivers/iommu/qcom_iommu.c
@@ -947,7 +947,7 @@  static void __exit qcom_iommu_exit(void)
 module_init(qcom_iommu_init);
 module_exit(qcom_iommu_exit);
 
-IOMMU_OF_DECLARE(qcom_iommu_dev, "qcom,msm-iommu-v1", NULL);
+IOMMU_OF_DECLARE(qcom_iommu_dev, "qcom,msm-iommu-v1");
 
 MODULE_DESCRIPTION("IOMMU API for QCOM IOMMU v1 implementations");
 MODULE_LICENSE("GPL v2");
diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
index cddfaff4d0b7..ae03752e8e3a 100644
--- a/include/linux/of_iommu.h
+++ b/include/linux/of_iommu.h
@@ -34,9 +34,7 @@  static inline const struct iommu_ops *of_iommu_configure(struct device *dev,
 
 extern struct of_device_id __iommu_of_table;
 
-typedef int (*of_iommu_init_fn)(struct device_node *);
-
-#define IOMMU_OF_DECLARE(name, compat, fn) \
-	_OF_DECLARE(iommu, name, compat, fn, of_iommu_init_fn)
+#define IOMMU_OF_DECLARE(name, compat) \
+	OF_DECLARE_1(iommu, name, compat, NULL)
 
 #endif /* __OF_IOMMU_H */