Re: [PATCH v2 2/3] remoteproc: k3-r5: Acquire mailbox handle during probe
From: Beleswar Prasad Padhi
Date: Wed Jun 05 2024 - 06:58:54 EST
Hi Andrew,
On 04/06/24 22:40, Andrew Davis wrote:
On 6/4/24 12:17 AM, Beleswar Padhi wrote:
Acquire the mailbox handle during device probe and do not release handle
in stop/detach routine or error paths. This removes the redundant
requests for mbox handle later during rproc start/attach. This also
allows to defer remoteproc driver's probe if mailbox is not probed yet.
Signed-off-by: Beleswar Padhi <b-padhi@xxxxxx>
---
drivers/remoteproc/ti_k3_r5_remoteproc.c | 74 +++++++++---------------
1 file changed, 26 insertions(+), 48 deletions(-)
diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c
b/drivers/remoteproc/ti_k3_r5_remoteproc.c
index 26362a509ae3c..7e02e3472ce25 100644
--- a/drivers/remoteproc/ti_k3_r5_remoteproc.c
+++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c
@@ -194,6 +194,10 @@ static void k3_r5_rproc_mbox_callback(struct
mbox_client *client, void *data)
const char *name = kproc->rproc->name;
u32 msg = omap_mbox_message(data);
+ /* Do not forward message to a detached core */
s/to/from
This is the receive side from the core.
+ if (kproc->rproc->state == RPROC_DETACHED)
+ return;
+
Do we need a similar check when sending messages to the core in
k3_r5_rproc_kick()? No one should be sending anything as they
all should have detached at this point, but something to double
check on.
dev_dbg(dev, "mbox msg: 0x%x\n", msg);
switch (msg) {
@@ -399,12 +403,9 @@ static int k3_r5_rproc_request_mbox(struct rproc
*rproc)
client->knows_txdone = false;
kproc->mbox = mbox_request_channel(client, 0);
- if (IS_ERR(kproc->mbox)) {
- ret = -EBUSY;
- dev_err(dev, "mbox_request_channel failed: %ld\n",
- PTR_ERR(kproc->mbox));
- return ret;
- }
+ if (IS_ERR(kproc->mbox))
+ return dev_err_probe(dev, PTR_ERR(kproc->mbox),
+ "mbox_request_channel failed\n");
This is good cleanup, but maybe something for its own patch.
/*
* Ping the remote processor, this is only for sanity-sake for
now;
@@ -552,10 +553,6 @@ static int k3_r5_rproc_start(struct rproc *rproc)
u32 boot_addr;
int ret;
- ret = k3_r5_rproc_request_mbox(rproc);
- if (ret)
- return ret;
-
boot_addr = rproc->bootaddr;
/* TODO: add boot_addr sanity checking */
dev_dbg(dev, "booting R5F core using boot addr = 0x%x\n",
boot_addr);
@@ -564,7 +561,7 @@ static int k3_r5_rproc_start(struct rproc *rproc)
core = kproc->core;
ret = ti_sci_proc_set_config(core->tsp, boot_addr, 0, 0);
if (ret)
- goto put_mbox;
+ return ret;
/* unhalt/run all applicable cores */
if (cluster->mode == CLUSTER_MODE_LOCKSTEP) {
@@ -580,13 +577,12 @@ static int k3_r5_rproc_start(struct rproc *rproc)
if (core != core0 && core0->rproc->state == RPROC_OFFLINE) {
dev_err(dev, "%s: can not start core 1 before core 0\n",
__func__);
- ret = -EPERM;
- goto put_mbox;
+ return -EPERM;
}
ret = k3_r5_core_run(core);
if (ret)
- goto put_mbox;
+ return ret;
}
return 0;
@@ -596,8 +592,6 @@ static int k3_r5_rproc_start(struct rproc *rproc)
if (k3_r5_core_halt(core))
dev_warn(core->dev, "core halt back failed\n");
}
-put_mbox:
- mbox_free_channel(kproc->mbox);
return ret;
}
@@ -658,8 +652,6 @@ static int k3_r5_rproc_stop(struct rproc *rproc)
goto out;
}
- mbox_free_channel(kproc->mbox);
-
return 0;
unroll_core_halt:
@@ -674,42 +666,22 @@ static int k3_r5_rproc_stop(struct rproc *rproc)
/*
* Attach to a running R5F remote processor (IPC-only mode)
*
- * The R5F attach callback only needs to request the mailbox, the
remote
- * processor is already booted, so there is no need to issue any TI-SCI
- * commands to boot the R5F cores in IPC-only mode. This callback is
invoked
- * only in IPC-only mode.
+ * The R5F attach callback is a NOP. The remote processor is already
booted, and
+ * all required resources have been acquired during probe routine,
so there is
+ * no need to issue any TI-SCI commands to boot the R5F cores in
IPC-only mode.
+ * This callback is invoked only in IPC-only mode and exists because
+ * rproc_validate() checks for its existence.
*/
-static int k3_r5_rproc_attach(struct rproc *rproc)
-{
- struct k3_r5_rproc *kproc = rproc->priv;
- struct device *dev = kproc->dev;
- int ret;
-
- ret = k3_r5_rproc_request_mbox(rproc);
- if (ret)
- return ret;
-
- dev_info(dev, "R5F core initialized in IPC-only mode\n");
- return 0;
-}
+static int k3_r5_rproc_attach(struct rproc *rproc) { return 0; }
I wonder if rproc_validate() should be updated to allow not
having an attach/detach for cases like this. Then we could drop
this function completely.
Not sure if we can update rproc_validate() for this usecase. Ideally, it
checks for an attach function if the core is detached, which should be
correct, right?
Will address all other comments in the next revision!
Andrew
/*
* Detach from a running R5F remote processor (IPC-only mode)
*
- * The R5F detach callback performs the opposite operation to attach
callback
- * and only needs to release the mailbox, the R5F cores are not
stopped and
- * will be left in booted state in IPC-only mode. This callback is
invoked
- * only in IPC-only mode.
+ * The R5F detach callback is a NOP. The R5F cores are not stopped
and will be
+ * left in booted state in IPC-only mode. This callback is invoked
only in
+ * IPC-only mode and exists for sanity sake.
*/
-static int k3_r5_rproc_detach(struct rproc *rproc)
-{
- struct k3_r5_rproc *kproc = rproc->priv;
- struct device *dev = kproc->dev;
-
- mbox_free_channel(kproc->mbox);
- dev_info(dev, "R5F core deinitialized in IPC-only mode\n");
- return 0;
-}
+static int k3_r5_rproc_detach(struct rproc *rproc) { return 0; }
/*
* This function implements the .get_loaded_rsc_table() callback
and is used
@@ -1277,6 +1249,10 @@ static int k3_r5_cluster_rproc_init(struct
platform_device *pdev)
kproc->rproc = rproc;
core->rproc = rproc;
+ ret = k3_r5_rproc_request_mbox(rproc);
+ if (ret)
+ return ret;
+
ret = k3_r5_rproc_configure_mode(kproc);
if (ret < 0)
goto err_config;
@@ -1393,6 +1369,8 @@ static void k3_r5_cluster_rproc_exit(void *data)
}
}
+ mbox_free_channel(kproc->mbox);
+
rproc_del(rproc);
k3_r5_reserved_mem_exit(kproc);