Re: [PATCH v25 2/2] soc: mediatek: Add Mediatek CMDQ helper

[Matthias Brugger]

On 29/09/2018 11:21, Houlong Wei wrote:
[...]

> +static int cmdq_pkt_append_command(struct cmdq_pkt *pkt, enum cmdq_code code,
> +                                u32 arg_a, u32 arg_b)
> +{
> +     u64 *cmd_ptr;
> +
> +     if (unlikely(pkt->cmd_buf_size + CMDQ_INST_SIZE > pkt->buf_size)) {
> +             pkt->cmd_buf_size += CMDQ_INST_SIZE;

Can you plesae provide some example code of a driver that will use this API, I
still don't understand why you need to update the cmd_buf_size here.

> +             WARN_ON(1);

can we add some debug information:
WARN_ON(1, "%s: buffer size too small for the amount of commands", __func__);

Would it make sense to use WARN_ONCE()?

> +             return -ENOMEM;
> +     }
> +     cmd_ptr = pkt->va_base + pkt->cmd_buf_size;
> +     (*cmd_ptr) = (u64)((code << CMDQ_OP_CODE_SHIFT) | arg_a) << 32 | arg_b;
> +     pkt->cmd_buf_size += CMDQ_INST_SIZE;
> +
> +     return 0;
> +}

Thanks,
Matthias