[PATCH v2 4/7] remoteproc: qcom: pas: Add late attach support for subsystems

Jingyi Wang
2025-10-29T08:05:52Z

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 | 63 +++++++++++++++++++++++++-
5 files changed, 165 insertions(+), 5 deletions(-)

diff --git a/drivers/remoteproc/qcom_q6v5.c b/drivers/remoteproc/qcom_q6v5.c
index 58d5b85e58cd..4ce9e43fc5c7 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);
+
/* 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;
}

@@ -172,6 +181,9 @@ 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;
@@ -234,6 +246,77 @@ 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
@@ -247,7 +330,7 @@ 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;

@@ -255,10 +338,14 @@ 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 3087d895b87f..ee9bf048820a 100644
--- a/drivers/remoteproc/qcom_q6v5_mss.c
+++ b/drivers/remoteproc/qcom_q6v5_mss.c
@@ -2165,7 +2165,7 @@ 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 158bcd6cc85c..b667c11aadb5 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;
@@ -59,6 +61,7 @@ struct qcom_pas_data {
int region_assign_count;
bool region_assign_shared;
int region_assign_vmid;
+ bool early_boot;
};

struct qcom_pas {
@@ -409,6 +412,8 @@ static int qcom_pas_stop(struct rproc *rproc)
if (pas->smem_host_id)
ret = qcom_smem_bust_hwspin_lock_by_host(pas->smem_host_id);

+ pas->q6v5.early_boot = false;
+
return ret;
}

@@ -434,6 +439,51 @@ 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,
@@ -442,6 +492,7 @@ 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 = {
@@ -765,7 +816,7 @@ 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;

@@ -779,6 +830,16 @@ 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