Hi Mathieu,
Le ven. 20 nov. 2020 à 15:37, Mathieu Poirier
<mathieu.poirier@xxxxxxxxxx> a écrit :
Hi Paul,
On Sun, Nov 15, 2020 at 11:50:56AM +0000, Paul Cercueil wrote:
Until now the remoteproc core would always default to trying to
boot the
remote processor at startup. The various remoteproc drivers could
however override that setting.
Whether or not we want the remote processor to boot, really depends
on
the nature of the processor itself - a processor built into a WiFi
chip
will need to be booted for the WiFi hardware to be usable, for
instance,
but a general-purpose co-processor does not have any predeterminated
function, and as such we cannot assume that the OS will want the
processor to be booted - yet alone that we have a single do-it-all
firmware to load.
If I understand correctly you have various remote processors that use
the same firmware
but are serving different purposes - is this correct?
That's the opposite actually. I have one remote processor which is
general-purpose, and as such userspace may or may not want it started
at boot time - depending on what it wants to do with it. The kernel
shouldn't decide itself whether or not the remote processor should be
started, because that's policy.
Add a 'auto_boot' module parameter that instructs the remoteproc
whether
or not it should auto-boot the remote processor, which will default
to
"true" to respect the previous behaviour.
Given that the core can't be a module I wonder if this isn't
something that
would be better off in the specific platform driver or the device
tree... Other
people might have an opinion as well.
Hardcoded in the platform driver or flagged in the device tree, doesn't
change the fundamental problem - it should be up to the userspace to
decide whether or not the remote processor should boot.
Cheers,
-Paul
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---
drivers/remoteproc/remoteproc_core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/remoteproc/remoteproc_core.c
b/drivers/remoteproc/remoteproc_core.c
index dab2c0f5caf0..687b1bfd49db 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -44,6 +44,11 @@
#define HIGH_BITS_MASK 0xFFFFFFFF00000000ULL
+static bool auto_boot = true;
+module_param(auto_boot, bool, 0400);
+MODULE_PARM_DESC(auto_boot,
+ "Auto-boot the remote processor [default=true]");
+
static DEFINE_MUTEX(rproc_list_mutex);
static LIST_HEAD(rproc_list);
static struct notifier_block rproc_panic_nb;
@@ -2176,7 +2181,7 @@ struct rproc *rproc_alloc(struct device *dev,
const char *name,
return NULL;
rproc->priv = &rproc[1];
- rproc->auto_boot = true;
+ rproc->auto_boot = auto_boot;
rproc->elf_class = ELFCLASSNONE;
rproc->elf_machine = EM_NONE;
--
2.29.2
