[Intel-gfx] [PATCH 03/13] drm/i915: Don't copy the DP source rates arrays

[Jindal, Sonika]

On 3/16/2015 3:04 PM, Ville Syrjälä wrote:
> On Mon, Mar 16, 2015 at 02:43:19PM +0530, Jindal, Sonika wrote:
>>
>>
>> On 3/12/2015 8:40 PM, ville.syrjala at linux.intel.com wrote:
>>> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>>>
>>> The source rates don't change, so we can just point the caller at the
>>> const arrays.
>>>
>>> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
>>> ---
>>>    drivers/gpu/drm/i915/intel_dp.c | 24 ++++++++++--------------
>>>    1 file changed, 10 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>>> index d638f5e..537f1d0 100644
>>> --- a/drivers/gpu/drm/i915/intel_dp.c
>>> +++ b/drivers/gpu/drm/i915/intel_dp.c
>>> @@ -1157,22 +1157,18 @@ intel_read_sink_rates(struct intel_dp *intel_dp, int *sink_rates)
>>>    }
>>>
>>>    static int
>>> -intel_read_source_rates(struct intel_dp *intel_dp, int *source_rates)
>>> +intel_dp_source_rates(struct intel_dp *intel_dp, const int **source_rates)
>>>    {
>>>    	struct drm_device *dev = intel_dp_to_dev(intel_dp);
>>> -	int i;
>>> -	int max_default_rate;
>>>
>>> -	if (INTEL_INFO(dev)->gen >= 9 && intel_dp->supported_rates[0]) {
>>> -		for (i = 0; i < ARRAY_SIZE(gen9_rates); ++i)
>>> -			source_rates[i] = gen9_rates[i];
>>> -	} else {
>>> -		/* Index of the max_link_bw supported + 1 */
>>> -		max_default_rate = (intel_dp_max_link_bw(intel_dp) >> 3) + 1;
>>> -		for (i = 0; i < max_default_rate; ++i)
>>> -			source_rates[i] = default_rates[i];
>>> +	if (INTEL_INFO(dev)->gen >= 9) {
>>> +		*source_rates = gen9_rates;
>>> +		return ARRAY_SIZE(gen9_rates);
>>>    	}
>>> -	return i;
>>> +
>>> +	*source_rates = default_rates;
>>> +
>>> +	return (intel_dp_max_link_bw(intel_dp) >> 3) + 1;
>> Now when intel_dp_max_link_bw doesn't do much, can this be simply
>> ARRAY_SIZE(default_rates)? and we can get away with this function.
>
> If you'll look at patch 6 you'll see me moving the source limitations
> from intel_dp_max_link_bw() to intel_dp_source_rates().
>
Yes, thats why I think we can remove the intel_dp_max_link_bw function 
altogether.
>>>    }
>>>
>>>    static void
>>> @@ -1269,12 +1265,12 @@ intel_dp_compute_config(struct intel_encoder *encoder,
>>>    	int link_avail, link_clock;
>>>    	int sink_rates[8];
>>>    	int supported_rates[8] = {0};
>>> -	int source_rates[8];
>>> +	const int *source_rates;
>>>    	int source_len, sink_len, supported_len;
>>>
>>>    	sink_len = intel_read_sink_rates(intel_dp, sink_rates);
>>>
>>> -	source_len = intel_read_source_rates(intel_dp, source_rates);
>>> +	source_len = intel_dp_source_rates(intel_dp, &source_rates);
>>>
>>>    	supported_len = intel_supported_rates(source_rates, source_len,
>>>    				sink_rates, sink_len, supported_rates);
>>>
>