Hi Tero, On 10/04/19 1:34 PM, Tero Kristo wrote: > On 10/04/2019 08:37, Lokesh Vutla wrote: >> TISCI protocol supports for enabling the device either with exclusive >> permissions for the requesting host or with sharing across the hosts. >> There are certain devices which are exclusive to Linux context and >> there are certain devices that are shared across different host contexts. >> So add support for getting this information from DT by increasing >> the power-domain cells to 2. >> >> Signed-off-by: Lokesh Vutla <lokeshvutla@xxxxxx> >> --- >> .../devicetree/bindings/soc/ti/sci-pm-domain.txt | 11 +++++++++-- >> MAINTAINERS | 1 + >> include/dt-bindings/soc/ti,sci_pm_domain.h | 9 +++++++++ >> 3 files changed, 19 insertions(+), 2 deletions(-) >> create mode 100644 include/dt-bindings/soc/ti,sci_pm_domain.h >> >> diff --git a/Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt >> b/Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt >> index f7b00a7c0f68..f541d1f776a2 100644 >> --- a/Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt >> +++ b/Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt >> @@ -19,8 +19,15 @@ child of the pmmc node. >> Required Properties: >> -------------------- >> - compatible: should be "ti,sci-pm-domain" >> -- #power-domain-cells: Must be 1 so that an id can be provided in each >> - device node. >> +- #power-domain-cells: Can be one of the following: >> + 1: Containing the device id of each node >> + 2: First entry should be device id >> + Second entry should be one of the floowing: >> + TI_SCI_PD_EXCLUSIVE: To allow device to be >> + exclusively controlled by >> + the requesting hosts. >> + TI_SCI_PD_SHARED: To allow device to be shared >> + by multiple hosts. > > One thing should be noted on this, the added flag is purely for software > configuration, and is not telling us anything about the HW / firmware. Software I does say about how firmware handles the requested device. > can decide to have the flag either way and it will work. I just wonder if DT is > the correct location to have something like this... Expect to have plenty of > churn on this by people swapping the permissions around according to their > use-case needs. Do you have any other suggestion to handle shared devices across VMs? Thanks and regards, Lokesh
