2024-06-04 05:22:53

by Beleswar Padhi

[permalink] [raw]
Subject: [PATCH v2 0/3] Defer TI's Remoteproc's Probe until Mailbox is Probed

Hello All,

This series adds deferred probe functionality in the TI's Remoteproc
drivers. The remoteproc drivers are dependent on the omap-mailbox driver
for mbox functionalities. Sometimes, the remoteproc driver could be
probed before the mailbox driver leading to rproc boot failures. Thus,
defer the probe routine of remoteproc drivers until mailbox driver is
probed by checking the mbox_request_channel handle in probe.

Also, use the acquired mbox handle in probe during rproc start/attach
routine instead of re-requesting. Do not free mbox handle during
stop/detach routine or error paths. This makes our k3_rproc_attach() &
k3_rproc_detach() functions NOP.

Also, use the devm_rproc_alloc() helper to automatically free created
rprocs incase of a probe defer.

v2: Changelog:
1) Added a check in k3_mbox_callback() to prevent forwarding messages to
a detached core.
2) Addressed Andrew's comments in v1 regarding some cleanup (Using
dev_err_probe, removing unused labels, adding matching mbox_free_channel
call during device removal).

Link to v1:
https://lore.kernel.org/all/[email protected]/

Beleswar Padhi (3):
remoteproc: k3-r5: Use devm_rproc_alloc() helper
remoteproc: k3-r5: Acquire mailbox handle during probe
remoteproc: k3-dsp: Acquire mailbox handle during probe routine

drivers/remoteproc/ti_k3_dsp_remoteproc.c | 76 ++++++++-------------
drivers/remoteproc/ti_k3_r5_remoteproc.c | 80 ++++++++---------------
2 files changed, 54 insertions(+), 102 deletions(-)

--
2.34.1



2024-06-04 05:23:36

by Beleswar Padhi

[permalink] [raw]
Subject: [PATCH v2 3/3] remoteproc: k3-dsp: Acquire mailbox handle during probe routine

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 <[email protected]>
---
drivers/remoteproc/ti_k3_dsp_remoteproc.c | 76 ++++++++---------------
1 file changed, 26 insertions(+), 50 deletions(-)

diff --git a/drivers/remoteproc/ti_k3_dsp_remoteproc.c b/drivers/remoteproc/ti_k3_dsp_remoteproc.c
index 3555b535b1683..edaa5e91aebe9 100644
--- a/drivers/remoteproc/ti_k3_dsp_remoteproc.c
+++ b/drivers/remoteproc/ti_k3_dsp_remoteproc.c
@@ -115,6 +115,10 @@ static void k3_dsp_rproc_mbox_callback(struct mbox_client *client, void *data)
const char *name = kproc->rproc->name;
u32 msg = omap_mbox_message(data);

+ /* Do not forward messages to a detached core */
+ if (kproc->rproc->state == RPROC_DETACHED)
+ return;
+
dev_dbg(dev, "mbox msg: 0x%x\n", msg);

switch (msg) {
@@ -230,12 +234,9 @@ static int k3_dsp_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");

/*
* Ping the remote processor, this is only for sanity-sake for now;
@@ -315,32 +316,23 @@ static int k3_dsp_rproc_start(struct rproc *rproc)
u32 boot_addr;
int ret;

- ret = k3_dsp_rproc_request_mbox(rproc);
- if (ret)
- return ret;
-
boot_addr = rproc->bootaddr;
if (boot_addr & (kproc->data->boot_align_addr - 1)) {
dev_err(dev, "invalid boot address 0x%x, must be aligned on a 0x%x boundary\n",
boot_addr, kproc->data->boot_align_addr);
- ret = -EINVAL;
- goto put_mbox;
+ return -EINVAL;
}

dev_err(dev, "booting DSP core using boot addr = 0x%x\n", boot_addr);
ret = ti_sci_proc_set_config(kproc->tsp, boot_addr, 0, 0);
if (ret)
- goto put_mbox;
+ return ret;

ret = k3_dsp_rproc_release(kproc);
if (ret)
- goto put_mbox;
+ return ret;

return 0;
-
-put_mbox:
- mbox_free_channel(kproc->mbox);
- return ret;
}

/*
@@ -353,8 +345,6 @@ static int k3_dsp_rproc_stop(struct rproc *rproc)
{
struct k3_dsp_rproc *kproc = rproc->priv;

- mbox_free_channel(kproc->mbox);
-
k3_dsp_rproc_reset(kproc);

return 0;
@@ -363,42 +353,22 @@ static int k3_dsp_rproc_stop(struct rproc *rproc)
/*
* Attach to a running DSP remote processor (IPC-only mode)
*
- * This rproc 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 DSP core. This callback is invoked only in IPC-only
- * mode.
+ * This rproc 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 DSP core. This callback
+ * is invoked only in IPC-only mode and exists because rproc_validate() checks
+ * for its existence.
*/
-static int k3_dsp_rproc_attach(struct rproc *rproc)
-{
- struct k3_dsp_rproc *kproc = rproc->priv;
- struct device *dev = kproc->dev;
- int ret;
-
- ret = k3_dsp_rproc_request_mbox(rproc);
- if (ret)
- return ret;
-
- dev_info(dev, "DSP initialized in IPC-only mode\n");
- return 0;
-}
+static int k3_dsp_rproc_attach(struct rproc *rproc) { return 0; }

/*
* Detach from a running DSP remote processor (IPC-only mode)
*
- * This rproc detach callback performs the opposite operation to attach callback
- * and only needs to release the mailbox, the DSP core is not stopped and will
- * be left to continue to run its booted firmware. This callback is invoked only
- * in IPC-only mode.
+ * This rproc detach callback is a NOP. The DSP core is not stopped and will be
+ * left to continue to run its booted firmware. This callback is invoked only in
+ * IPC-only mode and exists for sanity sake.
*/
-static int k3_dsp_rproc_detach(struct rproc *rproc)
-{
- struct k3_dsp_rproc *kproc = rproc->priv;
- struct device *dev = kproc->dev;
-
- mbox_free_channel(kproc->mbox);
- dev_info(dev, "DSP deinitialized in IPC-only mode\n");
- return 0;
-}
+static int k3_dsp_rproc_detach(struct rproc *rproc) { return 0; }

/*
* This function implements the .get_loaded_rsc_table() callback and is used
@@ -697,6 +667,10 @@ static int k3_dsp_rproc_probe(struct platform_device *pdev)
kproc->dev = dev;
kproc->data = data;

+ ret = k3_dsp_rproc_request_mbox(rproc);
+ if (ret)
+ return ret;
+
kproc->ti_sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
if (IS_ERR(kproc->ti_sci))
return dev_err_probe(dev, PTR_ERR(kproc->ti_sci),
@@ -789,6 +763,8 @@ static void k3_dsp_rproc_remove(struct platform_device *pdev)
if (ret)
dev_err(dev, "failed to detach proc (%pe)\n", ERR_PTR(ret));
}
+
+ mbox_free_channel(kproc->mbox);
}

static const struct k3_dsp_mem_data c66_mems[] = {
--
2.34.1