Hi Pranav,

This patch looks good to me.

Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>

Regards,

Sami Mujawar

Enable ACPI CPPC mechanism for RD-N2-Cfg1 as defined by the ACPI
specification. The implementation uses AMU registers accessible as
Fixed-feature Hardware (FFixedHW) for monitoring the performance.
Non-secure SCMI fastchannels are used to communicate with SCP to set
the desired performance. RD-N2-Cfg1 platform does not support CPPC
revision 1 and below. So update the _OSC method to let OSPM know about
this fact.

Signed-off-by: Pranav Madhu <pranav.madhu@arm.com>
---
 Platform/ARM/SgiPkg/AcpiTables/RdN2Cfg1/Dsdt.asl | 78 ++++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/Platform/ARM/SgiPkg/AcpiTables/RdN2Cfg1/Dsdt.asl b/Platform/ARM/SgiPkg/AcpiTables/RdN2Cfg1/Dsdt.asl
index 55f51cc26aff..411eff84334a 100644
--- a/Platform/ARM/SgiPkg/AcpiTables/RdN2Cfg1/Dsdt.asl
+++ b/Platform/ARM/SgiPkg/AcpiTables/RdN2Cfg1/Dsdt.asl
@@ -35,6 +35,12 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
             And (CAP0, Not (OSC_CAP_OS_INITIATED_LPI), CAP0)
             Or (STS0, OSC_STS_CAPABILITY_MASKED, STS0)
           }
+
+          If (And (CAP0, OSC_CAP_CPPC_SUPPORT)) {
+            /* CPPC revision 1 and below not supported */
+            And (CAP0, Not (OSC_CAP_CPPC_SUPPORT), CAP0)
+            Or (STS0, OSC_STS_CAPABILITY_MASKED, STS0)
+          }
         } Else {
           And (STS0, Not (OSC_STS_MASK), STS0)
           Or (STS0, Or (OSC_STS_FAILURE, OSC_STS_UNRECOGNIZED_REV), STS0)
@@ -133,6 +139,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 0)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000500, 0x06000504, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (0)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -151,6 +166,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 1)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000518, 0x0600051C, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (1)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -169,6 +193,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 2)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000530, 0x06000534, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (2)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -187,6 +220,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 3)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000548, 0x0600054C, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (3)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -205,6 +247,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 4)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000560, 0x06000564, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (4)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -223,6 +274,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 5)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000578, 0x0600057C, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (5)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -241,6 +301,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 6)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x06000590, 0x06000594, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (6)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }
@@ -259,6 +328,15 @@ DefinitionBlock ("DsdtTable.aml", "DSDT", 2, "ARMLTD", "ARMSGI",
         Name (_UID, 7)
         Name (_STA, 0xF)
 
+        Name (_CPC, Package()
+          CPPC_PACKAGE_INIT (0x060005A8, 0x060005AC, 20, 160, 160, 115, 115, 5)
+        )
+
+        Name (_PSD, Package () {
+          Package ()
+            PSD_INIT (7)
+        })
+
         Method (_LPI, 0, NotSerialized) {
           Return (\_SB.PLPI)
         }