From 729d3530a50417a88f3f485ba2dc88ff8adfeacb Mon Sep 17 00:00:00 2001 From: Lukasz Luba Date: Tue, 17 Dec 2019 13:43:45 +0000 Subject: drivers: firmware: scmi: Extend SCMI transport layer by trace events The SCMI transport layer communicates via mailboxes and shared memory with firmware running on a microcontroller. It is platform specific how long it takes to pass a SCMI message. The most sensitive requests are coming from CPUFreq subsystem, which might be used by the scheduler. Thus, there is a need to measure these delays and capture anomalies. This change introduces trace events wrapped around transfer code. According to Jim's suggestion a unique transfer_id is to distinguish similar entries which might have the same message id, protocol id and sequence. This is a case then there are some timeouts in transfers. Suggested-by: Jim Quinlan Signed-off-by: Lukasz Luba Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/driver.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'drivers/firmware/arm_scmi/driver.c') diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 26b2c438bd59..2c96f6b5a7d8 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -29,6 +29,9 @@ #include "common.h" +#define CREATE_TRACE_POINTS +#include + #define MSG_ID_MASK GENMASK(7, 0) #define MSG_XTRACT_ID(hdr) FIELD_GET(MSG_ID_MASK, (hdr)) #define MSG_TYPE_MASK GENMASK(9, 8) @@ -61,6 +64,8 @@ enum scmi_error_codes { static LIST_HEAD(scmi_list); /* Protection for the entire list */ static DEFINE_MUTEX(scmi_list_mutex); +/* Track the unique id for the transfers for debug & profiling purpose */ +static atomic_t transfer_last_id; /** * struct scmi_xfers_info - Structure to manage transfer information @@ -304,6 +309,7 @@ static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, xfer = &minfo->xfer_block[xfer_id]; xfer->hdr.seq = xfer_id; reinit_completion(&xfer->done); + xfer->transfer_id = atomic_inc_return(&transfer_last_id); return xfer; } @@ -374,6 +380,10 @@ static void scmi_rx_callback(struct mbox_client *cl, void *m) scmi_fetch_response(xfer, mem); + trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + msg_type); + if (msg_type == MSG_TYPE_DELAYED_RESP) complete(xfer->async_done); else @@ -439,6 +449,10 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) if (unlikely(!cinfo)) return -EINVAL; + trace_scmi_xfer_begin(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + xfer->hdr.poll_completion); + ret = mbox_send_message(cinfo->chan, xfer); if (ret < 0) { dev_dbg(dev, "mbox send fail %d\n", ret); @@ -478,6 +492,10 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) */ mbox_client_txdone(cinfo->chan, ret); + trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + xfer->hdr.status); + return ret; } -- cgit v1.2.3