Re: [PATCH] media: iris: add FPS calculation and VPP FW overhead in frequency formula

From: Vishnu Reddy

Date: Wed Mar 04 2026 - 06:20:33 EST



On 3/4/2026 3:04 PM, Konrad Dybcio wrote:
On 3/4/26 10:18 AM, Vishnu Reddy wrote:
The driver was using a fixed default FPS value when calculating the VPU
frequency. This caused wrong frequency requests for high‑frame‑rate
streams, for example 4K at 240 FPS. Because of this, the hardware was
running at a lower frequency than needed.

Add the FPS measurement based on the decoder input buffer arrival rate.
The measured FPS is stored per instance and used in frequency calculation
instead of the fixed default FPS. The value is clamped so that it does
not exceed platform limits. Add a VPP firmware overhead when running in
STAGE_2.

Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
---
[...]

+ /* 1.050 is VPP FW overhead */
+ if (inst->fw_caps[STAGE].value == STAGE_2)
+ vpp_cycles += div_u64(vpp_cycles * 50, 1000);
let's use mult_frac() and trim the trailing zero

ACK

Regards,
Vishnu Reddy


Konrad