[U-Boot] [PATCH v1 0/2] Allow platform specific service handling on PSCI

[Ang, Chee Hong <chee.hong.ang@intel.com>]

On Mon, 2019-03-11 at 15:48 -0400, Tom Rini wrote:
> On Mon, Mar 11, 2019 at 03:27:52PM +0000, Ang, Chee Hong wrote:
> > 
> > On Fri, 2019-03-08 at 13:09 -0500, Tom Rini wrote:
> > > 
> > > On Tue, Feb 12, 2019 at 12:27:01AM -0800, chee.hong.ang at intel.com
> > > wrote:
> > > 
> > > > 
> > > > 
> > > > From: "Ang, Chee Hong" <chee.hong.ang@intel.com>
> > > > 
> > > > Currently u-boot only support standard PSCI functions for power
> > > > management
> > > > and lack of convenient method to allow the users to extend the
> > > > PSCI
> > > > functions
> > > > to support platform specific services. Most of the u-boot users
> > > > still rely
> > > > on ATF (ARM Trusted Firmware) to handle the standard power
> > > > management and
> > > > platform specific PSCI services.
> > > > The purpose of this patchsets is to allow u-boot users to
> > > > support
> > > > their
> > > > own platform specific secure SMC/PSCI services without making
> > > > any
> > > > SMC calls to ATF. This will benefit the users who need to use
> > > > u-
> > > > boot as the
> > > > only bootloader and secure service provider without relying on
> > > > ATF.
> > > > 
> > > > Below is a simple code example for adding your own PSCI
> > > > functions:
> > > > 
> > > > #include <common.h>
> > > > #include <errno.h>
> > > > #include <asm/io.h>
> > > > #include <asm/psci.h>
> > > > #include <asm/secure.h>
> > > > 
> > > > #define PSCI_SMC64_FUNC_ID1	0xC2000001
> > > > #define PSCI_SMC64_FUNC_ID2	0xC2000002
> > > > 
> > > > static void __secure psci_plat_specific_func1(unsigned long
> > > > function_id)
> > > > {
> > > > 	/* Your code for handling the SMC/PSCI platform
> > > > specific
> > > > service 1 */
> > > > }
> > > > 
> > > > static void __secure psci_plat_specific_func2(unsigned long
> > > > function_id)
> > > > {
> > > > 	/* Your code for handling the SMC/PSCI platform
> > > > specific
> > > > service 2 */
> > > > }
> > > > 
> > > > DECLARE_SECURE_SVC(plat_specific_func1, PSCI_SMC64_FUNC_ID1,
> > > > 		   psci_plat_specific_func1);
> > > > DECLARE_SECURE_SVC(plat_specific_func2, PSCI_SMC64_FUNC_ID2,
> > > > 		   psci_plat_specific_func2);
> > > > 
> > > > Ang, Chee Hong (1):
> > > >   ARMv8: Disable fwcall when PSCI is enabled
> > > > 
> > > > Chee Hong Ang (1):
> > > >   ARMv8: Allow SiP service extensions on top of PSCI code
> > > Conceptually, I suppose this is a logical step.  In specifics,
> > > would
> > > we
> > > want to make this functionality opt-in, or no, that doesn't make
> > > sense?
> > > 
> > Allowing user to add platform specific service is part of SMC/PSCI
> > specification as specifed in ARM document (Table 2-1):
> > http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ARM_DEN00
> > 28B_
> > SMC_Calling_Convention.pdf
> > 
> > So I think this functionality should be part of the standard
> > PSCI/SMC
> > implementation. Currently u-boot only support standard PSCI call
> > which
> > is:
> > ----------------------------------------------
> > > 
> > > 0x84000000-0x8400001F  | PSCI 32-bit calls |
> > > 0xC4000000-0xC400001F  | PSCI 64-bit calls |
> > ----------------------------------------------
> > 
> > My implementation do not affect or alter the behavior of any
> > existing
> > standard PSCI calls.
> > 
> > Users can simply add their own platform specific services by using
> > the
> > service call range as below:
> > ----------------------------------------------------
> > > 
> > > 0xC2000000-0xC200FFFF | SMC64: SiP Service Calls |
> > > 0xC3000000-0xC300FFFF | SMC64: OEM Service Calls |
> > ----------------------------------------------------
> > 
> > For complete service call ranges please refer to Table 6-2 in the
> > ARM
> > document.
> OK, thanks!
> 
Any chance this enhancement get accepted ? Thanks.