Re: [PATCH 5/6] remoteproc: qcom: pas: Add late attach support for subsystems

[Jingyi Wang <jingyi.wang@oss.qualcomm.com>]

On 9/29/2025 5:35 PM, Dmitry Baryshkov wrote:
> On Mon, Sep 29, 2025 at 02:42:10PM +0800, Jingyi Wang wrote:
>>
>>
>> On 9/25/2025 11:04 AM, Dmitry Baryshkov wrote:
>>> On Wed, Sep 24, 2025 at 04:37:26PM -0700, Jingyi Wang wrote:
>>>> From: Gokul krishna Krishnakumar <Gokul.krishnakumar@oss.qualcomm>
>>>>
>>>> Subsystems can be brought out of reset by entities such as
>>>> bootloaders. Before attaching such subsystems, it is important to
>>>> check the state of the subsystem. This patch adds support to attach
>>>> to a subsystem by ensuring that the subsystem is in a sane state by
>>>> reading SMP2P bits and pinging the subsystem.
>>>>
>>>> Signed-off-by: Gokul krishna Krishnakumar <Gokul.krishnakumar@oss.qualcomm>
>>>> Co-developed-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com>
>>>> Signed-off-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com>
>>>> ---
>>>>  drivers/remoteproc/qcom_q6v5.c      | 89 ++++++++++++++++++++++++++++++++++++-
>>>>  drivers/remoteproc/qcom_q6v5.h      | 14 +++++-
>>>>  drivers/remoteproc/qcom_q6v5_adsp.c |  2 +-
>>>>  drivers/remoteproc/qcom_q6v5_mss.c  |  2 +-
>>>>  drivers/remoteproc/qcom_q6v5_pas.c  | 61 ++++++++++++++++++++++++-
>>>>  5 files changed, 163 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/drivers/remoteproc/qcom_q6v5.c b/drivers/remoteproc/qcom_q6v5.c
>>>> index 4ee5e67a9f03..cba05e1d6d52 100644
>>>> --- a/drivers/remoteproc/qcom_q6v5.c
>>>> +++ b/drivers/remoteproc/qcom_q6v5.c
>>>> @@ -94,6 +94,9 @@ static irqreturn_t q6v5_wdog_interrupt(int irq, void *data)
>>>>  	size_t len;
>>>>  	char *msg;
>>>>  
>>>> +	if (q6v5->early_boot)
>>>> +		complete(&q6v5->subsys_booted);
>>>
>>> Where do we clean this flag? I think you current code breaks restarting
>>> of ADSP. Once the ADSP is brought up, the flag should be cleared and
>>> further handling of the ADSP should follow the normal flow.
>>>
>>
>> q6v5->subsys_booted can not be cleared now, it is only checked in the 
>> qcom_pas_attach callback, so the bootup process will not be infected, 
>> we have tested shutdown->bootup process and it runs as expected.
> 
> I was more interested in clearing the early_boot flag.
> 

Sure, we can clear it in the stop callback.

>>
>> Thanks,
>> Jingyi
>>
>>
>>>> +
>>>>  	/* Sometimes the stop triggers a watchdog rather than a stop-ack */
>>>>  	if (!q6v5->running) {
>>>>  		complete(&q6v5->stop_done);
>>>> @@ -118,6 +121,9 @@ static irqreturn_t q6v5_fatal_interrupt(int irq, void *data)
>>>>  	size_t len;
>>>>  	char *msg;
>>>>  
>>>> +	if (q6v5->early_boot)
>>>> +		complete(&q6v5->subsys_booted);
>>>> +
>>>>  	if (!q6v5->running)
>>>>  		return IRQ_HANDLED;
>>>>  
>>>> @@ -139,6 +145,9 @@ static irqreturn_t q6v5_ready_interrupt(int irq, void *data)
>>>>  
>>>>  	complete(&q6v5->start_done);
>>>>  
>>>> +	if (q6v5->early_boot)
>>>> +		complete(&q6v5->subsys_booted);
>>>> +
>>>>  	return IRQ_HANDLED;
>>>>  }
>>>>  
>>>> @@ -170,6 +179,9 @@ static irqreturn_t q6v5_handover_interrupt(int irq, void *data)
>>>>  	if (q6v5->handover)
>>>>  		q6v5->handover(q6v5);
>>>>  
>>>> +	if (q6v5->early_boot)
>>>> +		complete(&q6v5->subsys_booted);
>>>> +
>>>>  	icc_set_bw(q6v5->path, 0, 0);
>>>>  
>>>>  	q6v5->handover_issued = true;
>>>> @@ -232,6 +244,77 @@ unsigned long qcom_q6v5_panic(struct qcom_q6v5 *q6v5)
>>>>  }
>>>>  EXPORT_SYMBOL_GPL(qcom_q6v5_panic);
>>>>  
>>>> +static irqreturn_t q6v5_pong_interrupt(int irq, void *data)
>>>> +{
>>>> +	struct qcom_q6v5 *q6v5 = data;
>>>> +
>>>> +	complete(&q6v5->ping_done);
>>>> +
>>>> +	return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +int qcom_q6v5_ping_subsystem(struct qcom_q6v5 *q6v5)
>>>> +{
>>>> +	int ret;
>>>> +	int ping_failed = 0;
>>>> +
>>>> +	reinit_completion(&q6v5->ping_done);
>>>> +
>>>> +	/* Set master kernel Ping bit */
>>>> +	ret = qcom_smem_state_update_bits(q6v5->ping_state,
>>>> +					  BIT(q6v5->ping_bit), BIT(q6v5->ping_bit));
>>>> +	if (ret) {
>>>> +		dev_err(q6v5->dev, "Failed to update ping bits\n");
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	ret = wait_for_completion_timeout(&q6v5->ping_done, msecs_to_jiffies(PING_TIMEOUT));
>>>> +	if (!ret) {
>>>> +		ping_failed = -ETIMEDOUT;
>>>> +		dev_err(q6v5->dev, "Failed to get back pong\n");
>>>> +	}
>>>> +
>>>> +	/* Clear ping bit master kernel */
>>>> +	ret = qcom_smem_state_update_bits(q6v5->ping_state, BIT(q6v5->ping_bit), 0);
>>>> +	if (ret) {
>>>> +		pr_err("Failed to clear master kernel bits\n");
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	if (ping_failed)
>>>> +		return ping_failed;
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(qcom_q6v5_ping_subsystem);
>>>> +
>>>> +int qcom_q6v5_ping_subsystem_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev)
>>>> +{
>>>> +	int ret = -ENODEV;
>>>> +
>>>> +	q6v5->ping_state = devm_qcom_smem_state_get(&pdev->dev, "ping", &q6v5->ping_bit);
>>>> +	if (IS_ERR(q6v5->ping_state)) {
>>>> +		dev_err(&pdev->dev, "failed to acquire smem state %ld\n",
>>>> +			PTR_ERR(q6v5->ping_state));
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	q6v5->pong_irq = platform_get_irq_byname(pdev, "pong");
>>>> +	if (q6v5->pong_irq < 0)
>>>> +		return q6v5->pong_irq;
>>>> +
>>>> +	ret = devm_request_threaded_irq(&pdev->dev, q6v5->pong_irq, NULL,
>>>> +					q6v5_pong_interrupt, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
>>>> +					"q6v5 pong", q6v5);
>>>> +	if (ret)
>>>> +		dev_err(&pdev->dev, "failed to acquire pong IRQ\n");
>>>> +
>>>> +	init_completion(&q6v5->ping_done);
>>>> +
>>>> +	return ret;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(qcom_q6v5_ping_subsystem_init);
>>>> +
>>>>  /**
>>>>   * qcom_q6v5_init() - initializer of the q6v5 common struct
>>>>   * @q6v5:	handle to be initialized
>>>> @@ -245,7 +328,7 @@ EXPORT_SYMBOL_GPL(qcom_q6v5_panic);
>>>>   */
>>>>  int qcom_q6v5_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev,
>>>>  		   struct rproc *rproc, int crash_reason, const char *load_state,
>>>> -		   void (*handover)(struct qcom_q6v5 *q6v5))
>>>> +		   bool early_boot, void (*handover)(struct qcom_q6v5 *q6v5))
>>>>  {
>>>>  	int ret;
>>>>  
>>>> @@ -253,10 +336,14 @@ int qcom_q6v5_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev,
>>>>  	q6v5->dev = &pdev->dev;
>>>>  	q6v5->crash_reason = crash_reason;
>>>>  	q6v5->handover = handover;
>>>> +	q6v5->early_boot = early_boot;
>>>>  
>>>>  	init_completion(&q6v5->start_done);
>>>>  	init_completion(&q6v5->stop_done);
>>>>  
>>>> +	if (early_boot)
>>>> +		init_completion(&q6v5->subsys_booted);
>>>> +
>>>>  	q6v5->wdog_irq = platform_get_irq_byname(pdev, "wdog");
>>>>  	if (q6v5->wdog_irq < 0)
>>>>  		return q6v5->wdog_irq;
>>>> diff --git a/drivers/remoteproc/qcom_q6v5.h b/drivers/remoteproc/qcom_q6v5.h
>>>> index 5a859c41896e..8a227bf70d7e 100644
>>>> --- a/drivers/remoteproc/qcom_q6v5.h
>>>> +++ b/drivers/remoteproc/qcom_q6v5.h
>>>> @@ -12,27 +12,35 @@ struct rproc;
>>>>  struct qcom_smem_state;
>>>>  struct qcom_sysmon;
>>>>  
>>>> +#define PING_TIMEOUT 500 /* in milliseconds */
>>>> +#define PING_TEST_WAIT 500 /* in milliseconds */
>>>> +
>>>>  struct qcom_q6v5 {
>>>>  	struct device *dev;
>>>>  	struct rproc *rproc;
>>>>  
>>>>  	struct qcom_smem_state *state;
>>>> +	struct qcom_smem_state *ping_state;
>>>>  	struct qmp *qmp;
>>>>  
>>>>  	struct icc_path *path;
>>>>  
>>>>  	unsigned stop_bit;
>>>> +	unsigned int ping_bit;
>>>>  
>>>>  	int wdog_irq;
>>>>  	int fatal_irq;
>>>>  	int ready_irq;
>>>>  	int handover_irq;
>>>>  	int stop_irq;
>>>> +	int pong_irq;
>>>>  
>>>>  	bool handover_issued;
>>>>  
>>>>  	struct completion start_done;
>>>>  	struct completion stop_done;
>>>> +	struct completion subsys_booted;
>>>> +	struct completion ping_done;
>>>>  
>>>>  	int crash_reason;
>>>>  
>>>> @@ -40,11 +48,13 @@ struct qcom_q6v5 {
>>>>  
>>>>  	const char *load_state;
>>>>  	void (*handover)(struct qcom_q6v5 *q6v5);
>>>> +
>>>> +	bool early_boot;
>>>>  };
>>>>  
>>>>  int qcom_q6v5_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev,
>>>>  		   struct rproc *rproc, int crash_reason, const char *load_state,
>>>> -		   void (*handover)(struct qcom_q6v5 *q6v5));
>>>> +		   bool early_boot, void (*handover)(struct qcom_q6v5 *q6v5));
>>>>  void qcom_q6v5_deinit(struct qcom_q6v5 *q6v5);
>>>>  
>>>>  int qcom_q6v5_prepare(struct qcom_q6v5 *q6v5);
>>>> @@ -52,5 +62,7 @@ int qcom_q6v5_unprepare(struct qcom_q6v5 *q6v5);
>>>>  int qcom_q6v5_request_stop(struct qcom_q6v5 *q6v5, struct qcom_sysmon *sysmon);
>>>>  int qcom_q6v5_wait_for_start(struct qcom_q6v5 *q6v5, int timeout);
>>>>  unsigned long qcom_q6v5_panic(struct qcom_q6v5 *q6v5);
>>>> +int qcom_q6v5_ping_subsystem(struct qcom_q6v5 *q6v5);
>>>> +int qcom_q6v5_ping_subsystem_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev);
>>>>  
>>>>  #endif
>>>> diff --git a/drivers/remoteproc/qcom_q6v5_adsp.c b/drivers/remoteproc/qcom_q6v5_adsp.c
>>>> index e98b7e03162c..1576b435b921 100644
>>>> --- a/drivers/remoteproc/qcom_q6v5_adsp.c
>>>> +++ b/drivers/remoteproc/qcom_q6v5_adsp.c
>>>> @@ -717,7 +717,7 @@ static int adsp_probe(struct platform_device *pdev)
>>>>  		goto disable_pm;
>>>>  
>>>>  	ret = qcom_q6v5_init(&adsp->q6v5, pdev, rproc, desc->crash_reason_smem,
>>>> -			     desc->load_state, qcom_adsp_pil_handover);
>>>> +			     desc->load_state, false, qcom_adsp_pil_handover);
>>>>  	if (ret)
>>>>  		goto disable_pm;
>>>>  
>>>> diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c
>>>> index 0c0199fb0e68..04e577541c8f 100644
>>>> --- a/drivers/remoteproc/qcom_q6v5_mss.c
>>>> +++ b/drivers/remoteproc/qcom_q6v5_mss.c
>>>> @@ -2156,7 +2156,7 @@ static int q6v5_probe(struct platform_device *pdev)
>>>>  	qproc->has_mba_logs = desc->has_mba_logs;
>>>>  
>>>>  	ret = qcom_q6v5_init(&qproc->q6v5, pdev, rproc, MPSS_CRASH_REASON_SMEM, "modem",
>>>> -			     qcom_msa_handover);
>>>> +			     false, qcom_msa_handover);
>>>>  	if (ret)
>>>>  		goto detach_proxy_pds;
>>>>  
>>>> diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
>>>> index 55a7da801183..99163e48a76a 100644
>>>> --- a/drivers/remoteproc/qcom_q6v5_pas.c
>>>> +++ b/drivers/remoteproc/qcom_q6v5_pas.c
>>>> @@ -35,6 +35,8 @@
>>>>  
>>>>  #define MAX_ASSIGN_COUNT 3
>>>>  
>>>> +#define EARLY_BOOT_RETRY_INTERVAL_MS 5000
>>>> +
>>>>  struct qcom_pas_data {
>>>>  	int crash_reason_smem;
>>>>  	const char *firmware_name;
>>>> @@ -58,6 +60,7 @@ struct qcom_pas_data {
>>>>  	int region_assign_count;
>>>>  	bool region_assign_shared;
>>>>  	int region_assign_vmid;
>>>> +	bool early_boot;
>>>>  };
>>>>  
>>>>  struct qcom_pas {
>>>> @@ -430,6 +433,51 @@ static unsigned long qcom_pas_panic(struct rproc *rproc)
>>>>  	return qcom_q6v5_panic(&pas->q6v5);
>>>>  }
>>>>  
>>>> +static int qcom_pas_attach(struct rproc *rproc)
>>>> +{
>>>> +	int ret;
>>>> +	struct qcom_pas *adsp = rproc->priv;
>>>> +	bool ready_state;
>>>> +	bool crash_state;
>>>> +
>>>> +	if (!adsp->q6v5.early_boot)
>>>> +		return -EINVAL;
>>>> +
>>>> +	ret = irq_get_irqchip_state(adsp->q6v5.fatal_irq,
>>>> +				    IRQCHIP_STATE_LINE_LEVEL, &crash_state);
>>>> +
>>>> +	if (crash_state) {
>>>> +		dev_err(adsp->dev, "Sub system has crashed before driver probe\n");
>>>> +		adsp->rproc->state = RPROC_CRASHED;
>>>> +		return -EINVAL;
>>>> +	}
>>>> +
>>>> +	ret = irq_get_irqchip_state(adsp->q6v5.ready_irq,
>>>> +				    IRQCHIP_STATE_LINE_LEVEL, &ready_state);
>>>> +
>>>> +	if (ready_state) {
>>>> +		dev_info(adsp->dev, "Sub system has boot-up before driver probe\n");
>>>> +		adsp->rproc->state = RPROC_DETACHED;
>>>> +	} else {
>>>> +		ret = wait_for_completion_timeout(&adsp->q6v5.subsys_booted,
>>>> +						  msecs_to_jiffies(EARLY_BOOT_RETRY_INTERVAL_MS));
>>>> +		if (!ret) {
>>>> +			dev_err(adsp->dev, "Timeout on waiting for subsystem interrupt\n");
>>>> +			return -ETIMEDOUT;
>>>> +		}
>>>> +	}
>>>> +
>>>> +	ret = qcom_q6v5_ping_subsystem(&adsp->q6v5);
>>>> +	if (ret) {
>>>> +		dev_err(adsp->dev, "Failed to ping subsystem, assuming device crashed\n");
>>>> +		rproc->state = RPROC_CRASHED;
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	adsp->q6v5.running = true;
>>>> +	return ret;
>>>> +}
>>>> +
>>>>  static const struct rproc_ops qcom_pas_ops = {
>>>>  	.unprepare = qcom_pas_unprepare,
>>>>  	.start = qcom_pas_start,
>>>> @@ -438,6 +486,7 @@ static const struct rproc_ops qcom_pas_ops = {
>>>>  	.parse_fw = qcom_register_dump_segments,
>>>>  	.load = qcom_pas_load,
>>>>  	.panic = qcom_pas_panic,
>>>> +	.attach = qcom_pas_attach,
>>>>  };
>>>>  
>>>>  static const struct rproc_ops qcom_pas_minidump_ops = {
>>>> @@ -760,7 +809,7 @@ static int qcom_pas_probe(struct platform_device *pdev)
>>>>  	pas->proxy_pd_count = ret;
>>>>  
>>>>  	ret = qcom_q6v5_init(&pas->q6v5, pdev, rproc, desc->crash_reason_smem,
>>>> -			     desc->load_state, qcom_pas_handover);
>>>> +			     desc->load_state, desc->early_boot, qcom_pas_handover);
>>>>  	if (ret)
>>>>  		goto detach_proxy_pds;
>>>>  
>>>> @@ -774,6 +823,16 @@ static int qcom_pas_probe(struct platform_device *pdev)
>>>>  	}
>>>>  
>>>>  	qcom_add_ssr_subdev(rproc, &pas->ssr_subdev, desc->ssr_name);
>>>> +
>>>> +	if (pas->q6v5.early_boot) {
>>>> +		ret = qcom_q6v5_ping_subsystem_init(&pas->q6v5, pdev);
>>>> +		if (ret)
>>>> +			dev_err(&pdev->dev,
>>>> +				"Unable to find ping/pong bits, falling back to firmware load\n");
>>>> +		else
>>>> +			pas->rproc->state = RPROC_DETACHED;
>>>> +	}
>>>> +
>>>>  	ret = rproc_add(rproc);
>>>>  	if (ret)
>>>>  		goto remove_ssr_sysmon;
>>>>
>>>> -- 
>>>> 2.25.1
>>>>
>>>
>>
>