hi Saravana,
On 02/10/2020 21:27, Laurent Pinchart wrote:
Hi Saravana,
On Fri, Oct 02, 2020 at 10:58:55AM -0700, Saravana Kannan wrote:
On Fri, Oct 2, 2020 at 10:55 AM Laurent Pinchart wrote:
On Fri, Oct 02, 2020 at 10:51:51AM -0700, Saravana Kannan wrote:
On Fri, Oct 2, 2020 at 7:08 AM Rob Herring <robh+dt@xxxxxxxxxx> wrote:
On Thu, Oct 1, 2020 at 5:59 PM Saravana Kannan <saravanak@xxxxxxxxxx> wrote:
When commit 93d2e4322aa7 ("of: platform: Batch fwnode parsing when
adding all top level devices") optimized the fwnode parsing when all top
level devices are added, it missed out optimizing this for platform
where the top level devices are added through the init_machine() path.
This commit does the optimization for all paths by simply moving the
fw_devlink_pause/resume() inside of_platform_default_populate().
Reported-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
---
drivers/of/platform.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 071f04da32c8..79972e49b539 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -501,8 +501,21 @@ int of_platform_default_populate(struct device_node *root,
const struct of_dev_auxdata *lookup,
struct device *parent)
{
- return of_platform_populate(root, of_default_bus_match_table, lookup,
- parent);
+ int ret;
+
+ /*
+ * fw_devlink_pause/resume() are only safe to be called around top
+ * level device addition due to locking constraints.
+ */
+ if (!root)
+ fw_devlink_pause();
+
+ ret = of_platform_populate(root, of_default_bus_match_table, lookup,
+ parent);
of_platform_default_populate() vs. of_platform_populate() is just a
different match table. I don't think the behavior should otherwise be
different.
There's also of_platform_probe() which has slightly different matching
behavior. It should not behave differently either with respect to
devlinks.
So I'm trying to do this only when the top level devices are added for
the first time. of_platform_default_populate() seems to be the most
common path. For other cases, I think we just need to call
fw_devlink_pause/resume() wherever the top level devices are added for
the first time. As I said in the other email, we can't add
fw_devlink_pause/resume() by default to of_platform_populate().
Do you have other ideas for achieving "call fw_devlink_pause/resume()
only when top level devices are added for the first time"?
I'm not an expert in this domain, but before investigating it, would you
be able to share a hack patch that implements this (in the most simple
way) to check if it actually fixes the delays I experience on my system
?
So I take it the patch I sent out didn't work for you? Can you tell me
what machine/DT you are using?
I've replied to the patch:
Based on v5.9-rc5, before the patch:
[ 0.652887] cpuidle: using governor menu
[ 12.349476] No ATAGs?
After the patch:
[ 0.650460] cpuidle: using governor menu
[ 12.262101] No ATAGs?
I'm using an AM57xx EVM, whose DT is not upstream, but it's essentially
a am57xx-beagle-x15-revb1.dts (it includes that DTS) with a few
additional nodes for GPIO keys, LCD panel, backlight and touchscreen.
hope you are receiving my mails as I've provided you with all required information already [1]
with below diff:
[ 4.177231] Freeing unused kernel memory: 1024K
[ 4.181892] Run /sbin/init as init process
The best time with [2] is
[ 3.100483] Run /sbin/init as init process
Still 1 sec lose.
Pls understand an issue - requirements here are like 500ms boot with can, Ethernet, camera and display on ;(
[1] https://lore.kernel.org/patchwork/patch/1316134/#1511276
[2] https://lore.kernel.org/patchwork/patch/1316134/#1511435
diff --git a/arch/arm/mach-omap2/pdata-quirks.c b/arch/arm/mach-omap2/pdata-quirks.c
index 2a4fe3e68b82..ac1ab8928190 100644
--- a/arch/arm/mach-omap2/pdata-quirks.c
+++ b/arch/arm/mach-omap2/pdata-quirks.c
@@ -591,7 +591,9 @@ void __init pdata_quirks_init(const struct of_device_id *omap_dt_match_table)
if (of_machine_is_compatible("ti,omap3"))
omap3_mcbsp_init();
pdata_quirks_check(auxdata_quirks);
+ fw_devlink_pause();
of_platform_populate(NULL, omap_dt_match_table,
omap_auxdata_lookup, NULL);
+ fw_devlink_resume();
pdata_quirks_check(pdata_quirks);
}
--
Best regards,
grygorii
