On 1/28/23 23:14, Patrick Wildt wrote:
The PCIe power domains are dependant on each other, which is why
the device tree makes both PCIe controllers reference the PCIe1
power domain, which then depends on the PCIe2 power domain.
Enabling the parent power domain used to be part of the driver,
but got partially lost in the rewrite. Add the enable call back
to be able to power up PCIe2.
Signed-off-by: Patrick Wildt <[email protected]>
---
drivers/power/domain/imx8m-power-domain.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/power/domain/imx8m-power-domain.c
b/drivers/power/domain/imx8m-power-domain.c
index 145f6ec0cd..d8e9ce3291 100644
--- a/drivers/power/domain/imx8m-power-domain.c
+++ b/drivers/power/domain/imx8m-power-domain.c
@@ -330,6 +330,9 @@ static int imx8m_power_domain_on(struct power_domain
*power_domain)
u32 pgc;
int ret;
+ if (pdata->has_pd)
+ power_domain_on(&pdata->pd);
+
if (pdata->clk.count) {
ret = clk_enable_bulk(&pdata->clk);
if (ret) {
One problem with this patch is that it does not turn the power domain
back OFF in imx8m_power_domain_off().
However, the driver should not have to care about that. It is the uclass
job to turn on any prerequisite power domains, which I believe happens in:
drivers/power/domain/power-domain-uclass.c
dev_power_domain_ctrl()
However, I suspect the code fails to recurse through more than one level
of power domains and therefore doesn't enable the power domains all the
way up the power domain tree. I also think this would be the fix --
recurse in dev_power_domain_ctrl() if there are upstream domains to
enable, enable them in that recursive call, and then enable the current
power domain using power_domain_on() .
Can you take a closer look at the uclass and the way it enables (or fail
to) the upstream domains instead ?
