Re: [PATCH 4/5] remoteproc: Add start and shutdown interface for q6v55

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Mon 24 Oct 08:55 PDT 2016, Avaneesh Kumar Dwivedi wrote:

> Adding start and shutdown interface to invoke q6v55 remoteproc.
> Additionally maintaining boot count and protecting start and
> shutdown sequence with lock.
> 
> Signed-off-by: Avaneesh Kumar Dwivedi <akdwived@codeaurora.org>
> ---
>  drivers/remoteproc/qcom_q6v5_pil.c | 166 +++++++++++++++++++++++++++++++++++--
>  1 file changed, 160 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/remoteproc/qcom_q6v5_pil.c b/drivers/remoteproc/qcom_q6v5_pil.c
> index 0fac8d8..dd19d41 100644
> --- a/drivers/remoteproc/qcom_q6v5_pil.c
> +++ b/drivers/remoteproc/qcom_q6v5_pil.c
> @@ -789,9 +789,8 @@ static int q6v5_mpss_load(struct q6v5 *qproc)
>  	return ret < 0 ? ret : 0;
>  }
>  
> -static int q6v5_start(struct rproc *rproc)
> +static int q6v5_start(struct q6v5 *qproc)
>  {
> -	struct q6v5 *qproc = (struct q6v5 *)rproc->priv;
>  	int ret;
>  
>  	ret = q6v5_regulator_enable(qproc);
> @@ -873,9 +872,75 @@ static int q6v5_start(struct rproc *rproc)
>  	return ret;
>  }
>  
> -static int q6v5_stop(struct rproc *rproc)
> +static int q6v55_start(struct q6v5 *qproc)
> +{

I'm sorry, but this function looks to take exactly the same steps as
q6v5_start(). The clock handling differs and you call a different reset
function, so please merge the clock handling and call the appropriate
reset function based on compatible.

> +	int ret;
> +
> +	ret = q6v55_proxy_vote(qproc);
> +	if (ret) {
> +		dev_err(qproc->dev, "failed to enable supplies\n");
> +		return ret;
> +	}
> +
> +	ret = q6v55_clk_enable(qproc);
> +	if (ret) {
> +		dev_err(qproc->dev, "failed to enable clocks\n");
> +		goto err_clks;
> +	}
> +
> +	pil_mss_restart_reg(qproc, 0);
> +
> +	writel_relaxed(qproc->mba_phys, qproc->rmb_base + RMB_MBA_IMAGE_REG);
> +
> +	ret = q6v6proc_reset(qproc);
> +	if (ret)
> +		goto halt_axi_ports;
> +
> +	ret = q6v5_rmb_mba_wait(qproc, 0, 5000);
> +	if (ret == -ETIMEDOUT) {
> +		dev_err(qproc->dev, "MBA boot timed out\n");
> +		goto halt_axi_ports;
> +	} else if (ret != RMB_MBA_XPU_UNLOCKED &&
> +		   ret != RMB_MBA_XPU_UNLOCKED_SCRIBBLED) {
> +		dev_err(qproc->dev, "MBA returned unexpected status %d\n", ret);
> +		ret = -EINVAL;
> +		goto halt_axi_ports;
> +	}
> +
> +	dev_info(qproc->dev, "MBA booted, loading mpss\n");
> +
> +	ret = q6v5_mpss_load(qproc);
> +	if (ret)
> +		goto halt_axi_ports;
> +
> +	ret = wait_for_completion_timeout(&qproc->start_done,
> +					  msecs_to_jiffies(10000));
> +	if (ret == 0) {
> +		dev_err(qproc->dev, "start timed out\n");
> +		ret = -ETIMEDOUT;
> +		goto halt_axi_ports;
> +	}
> +
> +	qproc->running = true;
> +
> +	/* TODO: All done, release the handover resources */
> +
> +	return 0;
> +
> +halt_axi_ports:
> +	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_q6);
> +	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_modem);
> +	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_nc);
> +	q6v55_clk_disable(qproc);
> +err_clks:
> +	pil_mss_restart_reg(qproc, 1);
> +	q6v55_proxy_unvote(qproc);
> +
> +	return ret;
> +}
> +
> +static int q6v5_stop(struct q6v5 *qproc)
>  {
> -	struct q6v5 *qproc = (struct q6v5 *)rproc->priv;
>  	int ret;
>  
>  	qproc->running = false;
> @@ -903,6 +968,93 @@ static int q6v5_stop(struct rproc *rproc)
>  	return 0;
>  }
>  
> +static int q6v55_stop(struct q6v5 *qproc)
> +{
> +	int ret;
> +	u64 val;
> +
> +	qcom_smem_state_update_bits(qproc->state,
> +				    BIT(qproc->stop_bit), BIT(qproc->stop_bit));
> +
> +	ret = wait_for_completion_timeout(&qproc->stop_done,
> +					  msecs_to_jiffies(5000));
> +	if (ret == 0)
> +		dev_err(qproc->dev, "timed out on wait\n");
> +
> +	qcom_smem_state_update_bits(qproc->state, BIT(qproc->stop_bit), 0);
> +
> +	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_q6);
> +	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_modem);
> +	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_nc);
> +
> +	/*
> +	* Assert QDSP6 I/O clamp, memory wordline clamp, and compiler
> +	* memory clamp as a software workaround to avoid high MX
> +	* current during LPASS/MSS restart.
> +	*/
> +
> +	val = readl_relaxed(qproc->reg_base + QDSP6SS_PWR_CTL_REG);
> +	val |= (Q6SS_CLAMP_IO | QDSP6v55_CLAMP_WL |
> +			QDSP6v55_CLAMP_QMC_MEM);
> +	writel_relaxed(val, qproc->reg_base + QDSP6SS_PWR_CTL_REG);

Is this "quirk" only for version 6? (5.5) Or should we clamp these on
the previous versions as well?

> +
> +	pil_mss_restart_reg(qproc, 1);
> +	if (qproc->running) {

Under what circumstances is will q6v55_stop() be called without
q6v55_start() succeeding?

> +		q6v55_clk_disable(qproc);
> +		q6v55_proxy_unvote(qproc);
> +		qproc->running = false;
> +	}
> +
> +	return 0;
> +}
> +
> +static int mss_boot(struct rproc *rproc)
> +{
> +	struct q6v5 *qproc = (struct q6v5 *)rproc->priv;
> +	int ret;
> +
> +	mutex_lock(&qproc->q6_lock);
> +	if (!qproc->boot_count) {

The remoteproc framework already have a reference count and will only
call this function in the transition from 0 to 1. So please drop this.

> +		if (qproc->is_q6v55) {
> +			ret = q6v55_start(qproc);
> +			if (ret)
> +				goto err_start;
> +		} else {
> +			ret = q6v5_start(qproc);
> +			if (ret)
> +				goto err_start;
> +		}
> +	}
> +	qproc->boot_count++;
> +	mutex_unlock(&qproc->q6_lock);
> +	return 0;
> +
> +err_start:
> +	mutex_unlock(&qproc->q6_lock);
> +	if (qproc->is_q6v55)
> +		q6v55_stop(qproc);
> +	else
> +		q6v5_stop(qproc);

The start functions should already have cleaned up all resources and
stopped the Hexagon in case of an error, so these should not be needed.

> +
> +	return ret;
> +}

Please inline the few differences into the q6v5_start() and q6_stop()
and drop these wrappers.

> +
> +static int mss_stop(struct rproc *rproc)
> +{
> +	struct q6v5 *qproc = (struct q6v5 *)rproc->priv;
> +	int ret;
> +
> +	mutex_lock(&qproc->q6_lock);
> +	if (!--qproc->boot_count) {
> +		if (qproc->is_q6v55)
> +			ret = q6v55_stop(qproc);
> +		else
> +			ret = q6v5_stop(qproc);
> +	}
> +	mutex_unlock(&qproc->q6_lock);
> +	return ret;
> +}
> +
>  static void *q6v5_da_to_va(struct rproc *rproc, u64 da, int len)
>  {
>  	struct q6v5 *qproc = rproc->priv;
> @@ -916,8 +1068,8 @@ static void *q6v5_da_to_va(struct rproc *rproc, u64 da, int len)
>  }
>  
>  static const struct rproc_ops q6v5_ops = {
> -	.start = q6v5_start,
> -	.stop = q6v5_stop,
> +	.start = mss_boot,
> +	.stop = mss_stop,
>  	.da_to_va = q6v5_da_to_va,
>  };
>  
> @@ -972,6 +1124,8 @@ static irqreturn_t q6v5_handover_interrupt(int irq, void *dev)
>  	struct q6v5 *qproc = dev;
>  
>  	complete(&qproc->start_done);
> +	if (qproc->is_q6v55)
> +		q6v55_proxy_unvote(qproc);

q6v5_start() is waiting for start_done to be completed, so please unvote
at the point where I have the comment "TODO: All done, release the
handover resources".

>  	return IRQ_HANDLED;
>  }
>  

Regards,
Bjorn