[Intel-gfx] [PATCH 8/8] drm/i915/skl+: debugfs entry to control IPC

[Mahesh Kumar]

Hi,

Thanks for review.


On Wednesday 09 August 2017 03:03 PM, Maarten Lankhorst wrote:
> Op 18-07-17 om 14:49 schreef Mahesh Kumar:
>> From: "Kumar, Mahesh" <mahesh1.kumar at intel.com>
>>
>> This patch creates an entry in debugfs to check the status of IPC.
>> This can also be used to enable/disable IPC in supported platforms.
>>
>> Signed-off-by: Mahesh Kumar <mahesh1.kumar at intel.com>
>> ---
>>   drivers/gpu/drm/i915/i915_debugfs.c | 73 ++++++++++++++++++++++++++++++++++++-
>>   1 file changed, 72 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
>> index 2ef75c1a6119..368f64de0fdc 100644
>> --- a/drivers/gpu/drm/i915/i915_debugfs.c
>> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
>> @@ -3592,6 +3592,76 @@ static int i915_wa_registers(struct seq_file *m, void *unused)
>>   	return 0;
>>   }
>>   
>> +static int i915_ipc_status_show(struct seq_file *m, void *data)
>> +{
>> +	struct drm_i915_private *dev_priv = m->private;
>> +
>> +	seq_printf(m, "Isochronous Priority Control: %s\n",
>> +			enableddisabled(dev_priv->ipc_enabled));
>> +	return 0;
>> +}
>> +
>> +static int i915_ipc_status_open(struct inode *inode, struct file *file)
>> +{
>> +	struct drm_i915_private *dev_priv = inode->i_private;
>> +
>> +	if (HAS_IPC(dev_priv))
>> +		return -ENODEV;
> I take it you didn't test this version of the patch? :p
hmm, I switched HAS_IPC macro in this version of patch only. will fix 
this. thanks for catching it.
>> +
>> +	return single_open(file, i915_ipc_status_show, dev_priv);
>> +}
>> +
>> +static ssize_t i915_ipc_status_write(struct file *file, const char __user *ubuf,
>> +				     size_t len, loff_t *offp)
>> +{
>> +	struct seq_file *m = file->private_data;
>> +	struct drm_i915_private *dev_priv = m->private;
>> +	char *newline;
>> +	char tmp[16];
>> +	bool enable;
>> +
>> +	if (HAS_IPC(dev_priv))
>> +		return -ENODEV;
> Again, though I would remove this check since you already test in open().
ok, will remove this check.
>> +	if (len >= sizeof(tmp))
>> +		return -EINVAL;
>> +
>> +	if (copy_from_user(tmp, ubuf, len))
>> +		return -EFAULT;
>> +
>> +	tmp[len] = '\0';
>> +
>> +	/* Strip newline, if any */
>> +	newline = strchr(tmp, '\n');
>> +	if (newline)
>> +		*newline = '\0';
>> +
>> +	if (strcmp(tmp, "0") == 0 || strcmp(tmp, "disable") == 0 ||
>> +	    strcmp(tmp, "off") == 0 || strcmp(tmp, "dis") == 0)
>> +		enable = false;
>> +	else if (strcmp(tmp, "1") == 0 || strcmp(tmp, "enable") == 0 ||
>> +	    strcmp(tmp, "on") == 0 || strcmp(tmp, "en") == 0)
>> +		enable = true;
>> +	else
>> +		return -EINVAL;
> Maybe replace with kstrtobool_from_user, and use yesno for ipc_enabled in show()? That way you won't have to do all these special cases here. :)
kstrtobool_from_user sounds good, will use this macro :)

-Mahesh
>> +
>> +	intel_runtime_pm_get(dev_priv);
>> +	dev_priv->ipc_enabled = enable;
>> +	intel_enable_ipc(dev_priv);
>> +	intel_runtime_pm_put(dev_priv);
>> +
>> +	return len;
>> +}
>> +
>> +static const struct file_operations i915_ipc_status_fops = {
>> +	.owner = THIS_MODULE,
>> +	.open = i915_ipc_status_open,
>> +	.read = seq_read,
>> +	.llseek = seq_lseek,
>> +	.release = single_release,
>> +	.write = i915_ipc_status_write
>> +};
>> +
>>   static int i915_ddb_info(struct seq_file *m, void *unused)
>>   {
>>   	struct drm_i915_private *dev_priv = node_to_i915(m->private);
>> @@ -4929,7 +4999,8 @@ static const struct i915_debugfs_files {
>>   	{"i915_dp_test_type", &i915_displayport_test_type_fops},
>>   	{"i915_dp_test_active", &i915_displayport_test_active_fops},
>>   	{"i915_guc_log_control", &i915_guc_log_control_fops},
>> -	{"i915_hpd_storm_ctl", &i915_hpd_storm_ctl_fops}
>> +	{"i915_hpd_storm_ctl", &i915_hpd_storm_ctl_fops},
>> +	{"i915_ipc_status", &i915_ipc_status_fops}
>>   };
>>   
>>   int i915_debugfs_register(struct drm_i915_private *dev_priv)
>