[PATCH 2/2] soc: qcom: rpmh-rsc: Avoid unnecessary checks on irq-done response

From: Abel Vesa
Date: Wed Nov 16 2022 - 06:33:43 EST


The RSC interrupt is issued only after the request is complete. For
fire-n-forget requests, the irq-done interrupt is sent after issuing the
RPMH request and for response-required request, the interrupt is
triggered only after all the requests are complete.

These unnecessary checks in the interrupt handler issues AHB reads from
a critical path. Lets remove them and clean up error handling in
rpmh_request data structures.

Co-developed-by: Lina Iyer <ilina@xxxxxxxxxxxxxx>
Signed-off-by: Lina Iyer <ilina@xxxxxxxxxxxxxx>
Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
---
drivers/soc/qcom/rpmh-internal.h | 4 +---
drivers/soc/qcom/rpmh-rsc.c | 22 +++-------------------
drivers/soc/qcom/rpmh.c | 10 ++--------
drivers/soc/qcom/trace-rpmh.h | 11 ++++-------
4 files changed, 10 insertions(+), 37 deletions(-)

diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h
index 0160c1669583..e3cf1beff803 100644
--- a/drivers/soc/qcom/rpmh-internal.h
+++ b/drivers/soc/qcom/rpmh-internal.h
@@ -59,7 +59,6 @@ struct tcs_group {
* @cmd: the payload that will be part of the @msg
* @completion: triggered when request is done
* @dev: the device making the request
- * @err: err return from the controller
* @needs_free: check to free dynamically allocated request object
*/
struct rpmh_request {
@@ -67,7 +66,6 @@ struct rpmh_request {
struct tcs_cmd cmd[MAX_RPMH_PAYLOAD];
struct completion *completion;
const struct device *dev;
- int err;
bool needs_free;
};

@@ -144,7 +142,7 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv,
void rpmh_rsc_invalidate(struct rsc_drv *drv);
void rpmh_rsc_write_next_wakeup(struct rsc_drv *drv);

-void rpmh_tx_done(const struct tcs_request *msg, int r);
+void rpmh_tx_done(const struct tcs_request *msg);
int rpmh_flush(struct rpmh_ctrlr *ctrlr);

#endif /* __RPM_INTERNAL_H__ */
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index cc24874d0a95..0f8b2249f889 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -439,10 +439,9 @@ static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable)
static irqreturn_t tcs_tx_done(int irq, void *p)
{
struct rsc_drv *drv = p;
- int i, j, err = 0;
+ int i;
unsigned long irq_status;
const struct tcs_request *req;
- struct tcs_cmd *cmd;

irq_status = readl_relaxed(drv->tcs_base + drv->regs[RSC_DRV_IRQ_STATUS]);

@@ -451,22 +450,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p)
if (WARN_ON(!req))
goto skip;

- err = 0;
- for (j = 0; j < req->num_cmds; j++) {
- u32 sts;
-
- cmd = &req->cmds[j];
- sts = read_tcs_cmd(drv, drv->regs[RSC_DRV_CMD_STATUS], i, j);
- if (!(sts & CMD_STATUS_ISSUED) ||
- ((req->wait_for_compl || cmd->wait) &&
- !(sts & CMD_STATUS_COMPL))) {
- pr_err("Incomplete request: %s: addr=%#x data=%#x",
- drv->name, cmd->addr, cmd->data);
- err = -EIO;
- }
- }
-
- trace_rpmh_tx_done(drv, i, req, err);
+ trace_rpmh_tx_done(drv, i, req);

/*
* If wake tcs was re-purposed for sending active
@@ -491,7 +475,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p)
spin_unlock(&drv->lock);
wake_up(&drv->tcs_wait);
if (req)
- rpmh_tx_done(req, err);
+ rpmh_tx_done(req);
}

return IRQ_HANDLED;
diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
index 3a53ed99d03c..08e09642d7f5 100644
--- a/drivers/soc/qcom/rpmh.c
+++ b/drivers/soc/qcom/rpmh.c
@@ -76,19 +76,13 @@ static struct rpmh_ctrlr *get_rpmh_ctrlr(const struct device *dev)
return &drv->client;
}

-void rpmh_tx_done(const struct tcs_request *msg, int r)
+void rpmh_tx_done(const struct tcs_request *msg)
{
struct rpmh_request *rpm_msg = container_of(msg, struct rpmh_request,
msg);
struct completion *compl = rpm_msg->completion;
bool free = rpm_msg->needs_free;

- rpm_msg->err = r;
-
- if (r)
- dev_err(rpm_msg->dev, "RPMH TX fail in msg addr=%#x, err=%d\n",
- rpm_msg->msg.cmds[0].addr, r);
-
if (!compl)
goto exit;

@@ -194,7 +188,7 @@ static int __rpmh_write(const struct device *dev, enum rpmh_state state,
} else {
/* Clean up our call by spoofing tx_done */
ret = 0;
- rpmh_tx_done(&rpm_msg->msg, ret);
+ rpmh_tx_done(&rpm_msg->msg);
}

return ret;
diff --git a/drivers/soc/qcom/trace-rpmh.h b/drivers/soc/qcom/trace-rpmh.h
index feb0cb455e37..12b676b20cb2 100644
--- a/drivers/soc/qcom/trace-rpmh.h
+++ b/drivers/soc/qcom/trace-rpmh.h
@@ -14,16 +14,15 @@

TRACE_EVENT(rpmh_tx_done,

- TP_PROTO(struct rsc_drv *d, int m, const struct tcs_request *r, int e),
+ TP_PROTO(struct rsc_drv *d, int m, const struct tcs_request *r),

- TP_ARGS(d, m, r, e),
+ TP_ARGS(d, m, r),

TP_STRUCT__entry(
__string(name, d->name)
__field(int, m)
__field(u32, addr)
__field(u32, data)
- __field(int, err)
),

TP_fast_assign(
@@ -31,12 +30,10 @@ TRACE_EVENT(rpmh_tx_done,
__entry->m = m;
__entry->addr = r->cmds[0].addr;
__entry->data = r->cmds[0].data;
- __entry->err = e;
),

- TP_printk("%s: ack: tcs-m: %d addr: %#x data: %#x errno: %d",
- __get_str(name), __entry->m, __entry->addr, __entry->data,
- __entry->err)
+ TP_printk("%s: ack: tcs-m: %d addr: %#x data: %#x",
+ __get_str(name), __entry->m, __entry->addr, __entry->data)
);

TRACE_EVENT(rpmh_send_msg,
--
2.34.1