Re: [PATCH 1/4] gpu: host1x: Enable Tegra186 syncpoint protection

[Mikko Perttunen <cyndis@kapsi.fi>]

On 08/19/2017 01:36 AM, Dmitry Osipenko wrote:
> On 18.08.2017 19:15, Mikko Perttunen wrote:
>> Since Tegra186 the Host1x hardware allows syncpoints to be assigned to
>> specific channels, preventing any other channels from incrementing
>> them.
>>
>> Enable this feature where available and assign syncpoints to channels
>> when submitting a job. Syncpoints are currently never unassigned from
>> channels since that would require extra work and is unnecessary with
>> the current channel allocation model.
>>
>> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
>> ---
>>   drivers/gpu/host1x/dev.h           | 16 ++++++++++++++++
>>   drivers/gpu/host1x/hw/channel_hw.c |  3 +++
>>   drivers/gpu/host1x/hw/syncpt_hw.c  | 26 ++++++++++++++++++++++++++
>>   drivers/gpu/host1x/syncpt.c        |  3 +++
>>   4 files changed, 48 insertions(+)
>>
>> diff --git a/drivers/gpu/host1x/dev.h b/drivers/gpu/host1x/dev.h
>> index def802c0a6bf..2432a30ff6e2 100644
>> --- a/drivers/gpu/host1x/dev.h
>> +++ b/drivers/gpu/host1x/dev.h
>> @@ -79,6 +79,9 @@ struct host1x_syncpt_ops {
>>   	u32 (*load)(struct host1x_syncpt *syncpt);
>>   	int (*cpu_incr)(struct host1x_syncpt *syncpt);
>>   	int (*patch_wait)(struct host1x_syncpt *syncpt, void *patch_addr);
>> +	void (*assign_channel)(struct host1x_syncpt *syncpt,
>> +	                       struct host1x_channel *channel);
>> +	void (*set_protection)(struct host1x *host, bool enabled);
>>   };
>>   
>>   struct host1x_intr_ops {
>> @@ -186,6 +189,19 @@ static inline int host1x_hw_syncpt_patch_wait(struct host1x *host,
>>   	return host->syncpt_op->patch_wait(sp, patch_addr);
>>   }
>>   
>> +static inline void host1x_hw_syncpt_assign_channel(struct host1x *host,
>> +						   struct host1x_syncpt *sp,
>> +						   struct host1x_channel *ch)
>> +{
>> +	return host->syncpt_op->assign_channel(sp, ch);
>> +}
>> +
>> +static inline void host1x_hw_syncpt_set_protection(struct host1x *host,
>> +						   bool enabled)
>> +{
>> +	return host->syncpt_op->set_protection(host, enabled);
>> +}
>> +
>>   static inline int host1x_hw_intr_init_host_sync(struct host1x *host, u32 cpm,
>>   			void (*syncpt_thresh_work)(struct work_struct *))
>>   {
>> diff --git a/drivers/gpu/host1x/hw/channel_hw.c b/drivers/gpu/host1x/hw/channel_hw.c
>> index 8447a56c41ca..0161da331702 100644
>> --- a/drivers/gpu/host1x/hw/channel_hw.c
>> +++ b/drivers/gpu/host1x/hw/channel_hw.c
>> @@ -147,6 +147,9 @@ static int channel_submit(struct host1x_job *job)
>>   
>>   	syncval = host1x_syncpt_incr_max(sp, user_syncpt_incrs);
>>   
>> +	/* assign syncpoint to channel */
>> +	host1x_hw_syncpt_assign_channel(host, sp, ch);
>> +
>>   	job->syncpt_end = syncval;
>>   
>>   	/* add a setclass for modules that require it */
>> diff --git a/drivers/gpu/host1x/hw/syncpt_hw.c b/drivers/gpu/host1x/hw/syncpt_hw.c
>> index 7b0270d60742..5d117ab1699e 100644
>> --- a/drivers/gpu/host1x/hw/syncpt_hw.c
>> +++ b/drivers/gpu/host1x/hw/syncpt_hw.c
>> @@ -106,6 +106,30 @@ static int syncpt_patch_wait(struct host1x_syncpt *sp, void *patch_addr)
>>   	return 0;
>>   }
>>   
>> +static void syncpt_assign_channel(struct host1x_syncpt *sp,
>> +				  struct host1x_channel *ch)
>> +{
>> +#if HOST1X_HW >= 6
>> +	struct host1x *host = sp->host;
>> +
>> +	if (!host->hv_regs)
>> +		return;
>> +
>> +	host1x_sync_writel(host,
>> +			   HOST1X_SYNC_SYNCPT_CH_APP_CH(ch ? ch->id : 0xff),
>> +			   HOST1X_SYNC_SYNCPT_CH_APP(sp->id));
>> +#endif
>> +}
>> +
>> +static void syncpt_set_protection(struct host1x *host, bool enabled)
>> +{
>> +#if HOST1X_HW >= 6
>> +	host1x_hypervisor_writel(host,
>> +				 enabled ? HOST1X_HV_SYNCPT_PROT_EN_CH_EN : 0,
>> +				 HOST1X_HV_SYNCPT_PROT_EN);
>> +#endif
>> +}
>> +
>>   static const struct host1x_syncpt_ops host1x_syncpt_ops = {
>>   	.restore = syncpt_restore,
>>   	.restore_wait_base = syncpt_restore_wait_base,
>> @@ -113,4 +137,6 @@ static const struct host1x_syncpt_ops host1x_syncpt_ops = {
>>   	.load = syncpt_load,
>>   	.cpu_incr = syncpt_cpu_incr,
>>   	.patch_wait = syncpt_patch_wait,
>> +	.assign_channel = syncpt_assign_channel,
>> +	.set_protection = syncpt_set_protection,
>>   };
>> diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c
>> index 048ac9e344ce..fe4d963b3e2a 100644
>> --- a/drivers/gpu/host1x/syncpt.c
>> +++ b/drivers/gpu/host1x/syncpt.c
>> @@ -398,6 +398,8 @@ int host1x_syncpt_init(struct host1x *host)
>>   	for (i = 0; i < host->info->nb_pts; i++) {
>>   		syncpt[i].id = i;
>>   		syncpt[i].host = host;
>> +
>> +		host1x_hw_syncpt_assign_channel(host, &syncpt[i], NULL);
>>   	}
>>   
>>   	for (i = 0; i < host->info->nb_bases; i++)
>> @@ -408,6 +410,7 @@ int host1x_syncpt_init(struct host1x *host)
>>   	host->bases = bases;
>>   
>>   	host1x_syncpt_restore(host);
>> +	host1x_hw_syncpt_set_protection(host, true);
> 
> Is it really okay to force the protection? Maybe protection should be enabled
> with a respect to CONFIG_TEGRA_HOST1X_FIREWALL? In that case we would have to
> avoid software jobs validation for Tegra124+.

I don't quite get your comment. The hardware syncpt protection layer 
being enabled should never hurt - it doesn't mess with any valid jobs. 
It's also only on Tegra186 so I'm not sure where the Tegra124 comes from.

Cheers,
Mikko

> 
>>   
>>   	/* Allocate sync point to use for clearing waits for expired fences */
>>   	host->nop_sp = host1x_syncpt_alloc(host, NULL, 0);
>>
> 
>