Re: [PATCH] gpu: host1x: fix compile error when IOMMU API is not available

From: Stefan Agner
Date: Thu Apr 11 2019 - 06:57:12 EST


On 11.04.2019 10:23, Ben Dooks wrote:
> On 2019-04-10 23:47, Stefan Agner wrote:
>> In case the IOMMU API is not available compiling host1x fails with
>> the following error:
>> In file included from drivers/gpu/host1x/hw/host1x06.c:27:
>> drivers/gpu/host1x/hw/channel_hw.c: In function âhost1x_channel_set_streamidâ:
>> drivers/gpu/host1x/hw/channel_hw.c:118:30: error: implicit
>> declaration of function
>> âdev_iommu_fwspec_getâ; did you mean âiommu_fwspec_freeâ?
>> [-Werror=implicit-function-declaration]
>> struct iommu_fwspec *spec = dev_iommu_fwspec_get(channel->dev->parent);
>> ^~~~~~~~~~~~~~~~~~~~
>> iommu_fwspec_free
>>
>> Fixes: de5469c21ff9 ("gpu: host1x: Program the channel stream ID")
>> Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
>
> would it be better to provide something like this i nthe header that
> defines dev_iommu_fwspec_get() to be:
>
> static inline struct iommu_fwspec *dev_iommu_fwspec_get(struct device
> *dev) { return NULL; }
>
> although returning an PTR_ERR would have been better.
>

The problem is that the code also accesses fields of struct iommu_fwspec
which are not defined in the !CONFIG_IOMMU_API case.

--
Stefan

>> ---
>> drivers/gpu/host1x/hw/channel_hw.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/host1x/hw/channel_hw.c
>> b/drivers/gpu/host1x/hw/channel_hw.c
>> index 27101c04a827..4030d64916f0 100644
>> --- a/drivers/gpu/host1x/hw/channel_hw.c
>> +++ b/drivers/gpu/host1x/hw/channel_hw.c
>> @@ -114,7 +114,7 @@ static inline void synchronize_syncpt_base(struct
>> host1x_job *job)
>>
>> static void host1x_channel_set_streamid(struct host1x_channel *channel)
>> {
>> -#if HOST1X_HW >= 6
>> +#if IS_ENABLED(CONFIG_IOMMU_API) && HOST1X_HW >= 6
>> struct iommu_fwspec *spec = dev_iommu_fwspec_get(channel->dev->parent);
>> u32 sid = spec ? spec->ids[0] & 0xffff : 0x7f;