Add ACPI support in fsl RCPM driver. This is required
to support ACPI S3 state. S3 is the ACPI sleep state
that is known as "sleep" or "suspend to RAM".
It essentially turns off most power of the system but
keeps memory powered.
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
@@ -57,8 +59,13 @@ static int rcpm_pm_prepare(struct device *dev)rcpm->wakeup_cells+1);/* Wakeup source should refer to current rcpm device */-if(ret||(np->phandle!=value[0]))-continue;+if(is_acpi_node(dev->fwnode)){+if(ret)+continue;+}else{+if(ret||(np->phandle!=value[0]))+continue;+}/* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the*numberofIPPDEXPCRregistercells,and"fsl,rcpm-wakeup"
Add ACPI support in fsl RCPM driver. This is required
to support ACPI S3 state. S3 is the ACPI sleep state
that is known as "sleep" or "suspend to RAM".
It essentially turns off most power of the system but
keeps memory powered.
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
Why does the OS need to program this device? Can't this be done by firmware?
quoted hunk
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
@@ -57,8 +59,13 @@ static int rcpm_pm_prepare(struct device *dev)rcpm->wakeup_cells+1);/* Wakeup source should refer to current rcpm device */-if(ret||(np->phandle!=value[0]))-continue;+if(is_acpi_node(dev->fwnode)){+if(ret)+continue;+}else{+if(ret||(np->phandle!=value[0]))+continue;+}/* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the*numberofIPPDEXPCRregistercells,and"fsl,rcpm-wakeup"
Add ACPI support in fsl RCPM driver. This is required to support ACPI S3 state.
S3 is the ACPI sleep state that is known as "sleep" or "suspend to RAM".
It essentially turns off most power of the system but keeps memory powered.
Actually the low power mode is to gate clocks rather than power down on Layerscape platforms.
quoted hunk
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index
@@ -57,8 +59,13 @@ static int rcpm_pm_prepare(struct device *dev)rcpm->wakeup_cells+1);/* Wakeup source should refer to current rcpm device */-if(ret||(np->phandle!=value[0]))-continue;+if(is_acpi_node(dev->fwnode)){+if(ret)+continue;+}else{+if(ret||(np->phandle!=value[0]))+continue;+}/* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the*numberofIPPDEXPCRregistercells,and"fsl,rcpm-wakeup"
Hi Ard,
On Tuesday, September 15, 2020 7:10 PM, Ard Biesheuvel wrote:
Subject: Re: [PATCH v1] soc: fsl: rcpm: Add ACPI support
On 9/15/20 1:06 PM, kuldip dwivedi wrote:
quoted
Add ACPI support in fsl RCPM driver. This is required to support ACPI
S3 state. S3 is the ACPI sleep state that is known as "sleep" or
"suspend to RAM".
It essentially turns off most power of the system but keeps memory
powered.
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
Why does the OS need to program this device? Can't this be done by
firmware?
This device is use to tell HW which IP (such as USB, SDHC, SATA, etc) should not be
clock gated during system enter low power state (to allow that IP work as a
wakeup source). And user does this configuration in device tree. So implement
this RCPM driver to do it in kernel rather than firmware.
Regards,
Ran
quoted
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index
@@ -57,8 +59,13 @@ static int rcpm_pm_prepare(struct device *dev)rcpm->wakeup_cells+1);/* Wakeup source should refer to current rcpm device */-if(ret||(np->phandle!=value[0]))-continue;+if(is_acpi_node(dev->fwnode)){+if(ret)+continue;+}else{+if(ret||(np->phandle!=value[0]))+continue;+}/* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the*numberofIPPDEXPCRregistercells,and"fsl,rcpm-wakeup"
Hi Ard,
On Tuesday, September 15, 2020 7:10 PM, Ard Biesheuvel wrote:
quoted
Subject: Re: [PATCH v1] soc: fsl: rcpm: Add ACPI support
On 9/15/20 1:06 PM, kuldip dwivedi wrote:
quoted
Add ACPI support in fsl RCPM driver. This is required to support ACPI
S3 state. S3 is the ACPI sleep state that is known as "sleep" or
"suspend to RAM".
It essentially turns off most power of the system but keeps memory
powered.
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
Why does the OS need to program this device? Can't this be done by
firmware?
This device is use to tell HW which IP (such as USB, SDHC, SATA, etc) should not be
clock gated during system enter low power state (to allow that IP work as a
wakeup source). And user does this configuration in device tree.
The point of ACPI is *not* to describe a DT topology using a table
format that is not suited for it. The point of ACPI is to describe a
machine that is more abstracted from the hardware than is typically
possible with DT, where the abstractions are implemented by AML code
that is provided by the firmware, but executed in the context of the OS.
So the idea is *not* finding the shortest possible path to get your
existing DT driver code running on a system that boots via ACPI.
Instead, you should carefully think about the abstract ACPI machine that
you will expose to the OS, and hide everything else in firmware.
In this particular case, it seems like your USB, SDHC and SATA device
objects may need power state dependent AML methods that program this
block directly.
So implement
this RCPM driver to do it in kernel rather than firmware.
Regards,
Ran
quoted
quoted
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index
@@ -57,8 +59,13 @@ static int rcpm_pm_prepare(struct device *dev)rcpm->wakeup_cells+1);/* Wakeup source should refer to current rcpm device */-if(ret||(np->phandle!=value[0]))-continue;+if(is_acpi_node(dev->fwnode)){+if(ret)+continue;+}else{+if(ret||(np->phandle!=value[0]))+continue;+}/* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the*numberofIPPDEXPCRregistercells,and"fsl,rcpm-wakeup"
Hi Ard,
On Wednesday, September 16, 2020 2:11 PM, Ard Biesheuvel wrote:
Subject: Re: [PATCH v1] soc: fsl: rcpm: Add ACPI support
On 9/16/20 3:32 AM, Ran Wang wrote:
quoted
Hi Ard,
On Tuesday, September 15, 2020 7:10 PM, Ard Biesheuvel wrote:
quoted
Subject: Re: [PATCH v1] soc: fsl: rcpm: Add ACPI support
On 9/15/20 1:06 PM, kuldip dwivedi wrote:
quoted
Add ACPI support in fsl RCPM driver. This is required to support
ACPI
S3 state. S3 is the ACPI sleep state that is known as "sleep" or
"suspend to RAM".
It essentially turns off most power of the system but keeps memory
powered.
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
Why does the OS need to program this device? Can't this be done by
firmware?
This device is use to tell HW which IP (such as USB, SDHC, SATA, etc)
should not be clock gated during system enter low power state (to
allow that IP work as a wakeup source). And user does this configuration in
device tree.
The point of ACPI is *not* to describe a DT topology using a table format that
is not suited for it. The point of ACPI is to describe a machine that is more
abstracted from the hardware than is typically possible with DT, where the
abstractions are implemented by AML code that is provided by the firmware,
but executed in the context of the OS.
So the idea is *not* finding the shortest possible path to get your existing DT
driver code running on a system that boots via ACPI.
Instead, you should carefully think about the abstract ACPI machine that you
will expose to the OS, and hide everything else in firmware.
In this particular case, it seems like your USB, SDHC and SATA device objects
may need power state dependent AML methods that program this block
directly.
Actually the scenario is a little bit complicated for RCPM function: it need to query
kernel wakeup source framework (see for_each_wakeup_source(ws)) to fetch all
potential candidates then do the programming accordingly. If we implement
this logic in AML methods, I have no idea how to collect those information stored in
wakeup source data of kernel.
Regards,
Ran
quoted
So implement
this RCPM driver to do it in kernel rather than firmware.
Regards,
Ran
quoted
quoted
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index
On Wed, Sep 16, 2020 at 1:12 AM Ard Biesheuvel [off-list ref] wrote:
On 9/16/20 3:32 AM, Ran Wang wrote:
quoted
Hi Ard,
On Tuesday, September 15, 2020 7:10 PM, Ard Biesheuvel wrote:
quoted
Subject: Re: [PATCH v1] soc: fsl: rcpm: Add ACPI support
On 9/15/20 1:06 PM, kuldip dwivedi wrote:
quoted
Add ACPI support in fsl RCPM driver. This is required to support ACPI
S3 state. S3 is the ACPI sleep state that is known as "sleep" or
"suspend to RAM".
It essentially turns off most power of the system but keeps memory
powered.
Signed-off-by: tanveer <redacted>
Signed-off-by: kuldip dwivedi <redacted>
Why does the OS need to program this device? Can't this be done by
firmware?
This device is use to tell HW which IP (such as USB, SDHC, SATA, etc) should not be
clock gated during system enter low power state (to allow that IP work as a
wakeup source). And user does this configuration in device tree.
The point of ACPI is *not* to describe a DT topology using a table
format that is not suited for it. The point of ACPI is to describe a
machine that is more abstracted from the hardware than is typically
possible with DT, where the abstractions are implemented by AML code
that is provided by the firmware, but executed in the context of the OS.
So the idea is *not* finding the shortest possible path to get your
existing DT driver code running on a system that boots via ACPI.
Instead, you should carefully think about the abstract ACPI machine that
you will expose to the OS, and hide everything else in firmware.
In this particular case, it seems like your USB, SDHC and SATA device
objects may need power state dependent AML methods that program this
block directly.
The platform PM driver was created to support PM on systems without a
runtime PM firmware. Even with PSCI firmware on later systems, there
is no standard interface to communicate the wakeup source information
directly from peripheral drivers to the PSCI firmware. So we still
need this platform power management driver in kernel to deal with this
setup for non-ACPI scenarios. From the code re-use perspective, I
think it is probably better to keep this generic implementation in
kernel instead of moving it to ACPI byte-code for each platform.
quoted
So implement
this RCPM driver to do it in kernel rather than firmware.
Regards,
Ran
quoted
quoted
---
Notes:
1. Add ACPI match table
2. NXP team members are added for confirming HID changes
3. There is only one node in ACPI so no need to check for
current device explicitly
4. These changes are tested on LX2160A and LS1046A platforms
drivers/soc/fsl/rcpm.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index
@@ -57,8 +59,13 @@ static int rcpm_pm_prepare(struct device *dev)rcpm->wakeup_cells+1);/* Wakeup source should refer to current rcpm device */-if(ret||(np->phandle!=value[0]))-continue;+if(is_acpi_node(dev->fwnode)){+if(ret)+continue;+}else{+if(ret||(np->phandle!=value[0]))+continue;+}/* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the*numberofIPPDEXPCRregistercells,and"fsl,rcpm-wakeup"