| Message ID | 20230706074629.3527654-1-alexander.stein@ew.tq-group.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/1] soc: imx: imx93-blk-ctrl: Add dedicated lockdep class for nested genpd locks | expand |
On Thu, Jul 06, 2023 at 09:46:29AM +0200, Alexander Stein wrote: > This is the same approach as being used within imx8mp-blk-ctrl. This fixes > the lockdep warning about 'possible recursive locking detected' with the > following (reduced) backtrace: > genpd_lock_mtx+0x14/0x1c > genpd_runtime_resume+0x108/0x308 > __rpm_callback+0x44/0x19c > rpm_callback+0x64/0x70 > rpm_resume+0x438/0x6d8 > __pm_runtime_resume+0x54/0xb0 > imx93_blk_ctrl_power_on+0x100/0x294 > _genpd_power_on+0x8c/0x16c > genpd_power_on.part.0+0xa0/0x1a0 > __genpd_dev_pm_attach+0x14c/0x2e4 > genpd_dev_pm_attach+0x58/0x64 > dev_pm_domain_attach+0x1c/0x2c > > Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Applied, thanks!
diff --git a/drivers/soc/imx/imx93-blk-ctrl.c b/drivers/soc/imx/imx93-blk-ctrl.c index 6cd7f2015b5a..185d428cebac 100644 --- a/drivers/soc/imx/imx93-blk-ctrl.c +++ b/drivers/soc/imx/imx93-blk-ctrl.c @@ -187,6 +187,8 @@ static int imx93_blk_ctrl_power_off(struct generic_pm_domain *genpd) return 0; } +static struct lock_class_key blk_ctrl_genpd_lock_class; + static int imx93_blk_ctrl_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -269,6 +271,19 @@ static int imx93_blk_ctrl_probe(struct platform_device *pdev) goto cleanup_pds; } + /* + * We use runtime PM to trigger power on/off of the upstream GPC + * domain, as a strict hierarchical parent/child power domain + * setup doesn't allow us to meet the sequencing requirements. + * This means we have nested locking of genpd locks, without the + * nesting being visible at the genpd level, so we need a + * separate lock class to make lockdep aware of the fact that + * this are separate domain locks that can be nested without a + * self-deadlock. + */ + lockdep_set_class(&domain->genpd.mlock, + &blk_ctrl_genpd_lock_class); + bc->onecell_data.domains[i] = &domain->genpd; }
This is the same approach as being used within imx8mp-blk-ctrl. This fixes the lockdep warning about 'possible recursive locking detected' with the following (reduced) backtrace: genpd_lock_mtx+0x14/0x1c genpd_runtime_resume+0x108/0x308 __rpm_callback+0x44/0x19c rpm_callback+0x64/0x70 rpm_resume+0x438/0x6d8 __pm_runtime_resume+0x54/0xb0 imx93_blk_ctrl_power_on+0x100/0x294 _genpd_power_on+0x8c/0x16c genpd_power_on.part.0+0xa0/0x1a0 __genpd_dev_pm_attach+0x14c/0x2e4 genpd_dev_pm_attach+0x58/0x64 dev_pm_domain_attach+0x1c/0x2c Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> --- drivers/soc/imx/imx93-blk-ctrl.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)