Re: [PATCH v6 3/4] media: venus: Update to bitrate based clock scaling

Stanimir Varbanov
2019-07-29T07:54:37Z

On 7/22/19 12:07 PM, Aniket Masule wrote:
> Introduced clock scaling using bitrate, preavious
> calculations consider only the cycles per mb.
> Also, clock scaling is now triggered before every
> buffer being queued to the device. This helps in
> deciding precise clock cycles required.
>
> Signed-off-by: Aniket Masule <amasule@codeaurora.org>
> ---
> drivers/media/platform/qcom/venus/helpers.c | 33 +++++++++++++++++++++++++----
> 1 file changed, 29 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/platform/qcom/venus/helpers.c b/drivers/media/platform/qcom/venus/helpers.c
> index 2c976e4..edf403d 100644
> --- a/drivers/media/platform/qcom/venus/helpers.c
> +++ b/drivers/media/platform/qcom/venus/helpers.c
> @@ -399,17 +399,26 @@ static int scale_clocks(struct venus_inst *inst)
> return ret;
> }
>
> -static unsigned long calculate_vpp_freq(struct venus_inst *inst)
> +static unsigned long calculate_inst_freq(struct venus_inst *inst,
> + unsigned long filled_len)
> {
> - unsigned long vpp_freq = 0;
> + unsigned long vpp_freq = 0, vsp_freq = 0;
> + u64 fps = inst->fps;
> u32 mbs_per_sec;
>
> mbs_per_sec = load_per_instance(inst);
> vpp_freq = mbs_per_sec * inst->clk_data.codec_freq_data->vpp_freq;
> /* 21 / 20 is overhead factor */
> vpp_freq += vpp_freq / 20;
> + vsp_freq = mbs_per_sec * inst->clk_data.codec_freq_data->vsp_freq;
>
> - return vpp_freq;
> + /* 10 / 7 is overhead factor */
> + if (inst->session_type == VIDC_SESSION_TYPE_ENC)
> + vsp_freq += (inst->controls.enc.bitrate * 10) / 7;
> + else
> + vsp_freq += ((fps * filled_len * 8) * 10) / 7;
> +
> + return max(vpp_freq, vsp_freq);
> }
>
> static int scale_clocks_v4(struct venus_inst *inst)
> @@ -417,13 +426,27 @@ static int scale_clocks_v4(struct venus_inst *inst)
> struct venus_core *core = inst->core;
> const struct freq_tbl *table = core->res->freq_tbl;
> unsigned int num_rows = core->res->freq_tbl_size;
> + struct v4l2_m2m_ctx *m2m_ctx = inst->m2m_ctx;
> struct clk *clk = core->clks[0];
> struct device *dev = core->dev;
> unsigned int i;
> unsigned long freq = 0, freq_core1 = 0, freq_core2 = 0;
> + unsigned long filled_len = 0;
> + struct venus_buffer *buf, *n;
> + struct vb2_buffer *vb;
> int ret;
>
> - freq = calculate_vpp_freq(inst);
> + mutex_lock(&inst->lock);

the lock is not needed and having it will produce a deadlock.

> + v4l2_m2m_for_each_src_buf_safe(m2m_ctx, buf, n) {
> + vb = &buf->vb.vb2_buf;
> + filled_len = max(filled_len, vb2_get_plane_payload(vb, 0));
> + }
> + mutex_unlock(&inst->lock);
> +
> + if (inst->session_type == VIDC_SESSION_TYPE_DEC && !filled_len)
> + return 0;
> +
> + freq = calculate_inst_freq(inst, filled_len);
>
> if (freq > table[0].freq)
> dev_warn(dev, "HW is overloaded, needed: %lu max: %lu\n",
> @@ -1093,6 +1116,8 @@ void venus_helper_vb2_buf_queue(struct vb2_buffer *vb)
> if (ret)
> goto unlock;
>
> + load_scale_clocks(inst);
> +
> ret = session_process_buf(inst, vbuf);
> if (ret)
> return_buf_error(inst, vbuf);
>

--
regards,
Stan