Platform/RPi: Make 3GB/4GB a runtime (BIOS setup) choice

Currently some OSes (e.g FreeBSD) can make full use of the maximum
4 GB of RAM a Raspberry Pi 4 can offer, whereas others (e.g. Linux)
must be restricted to only the first 3 GB.

Previously this was a compile-time choice chosen by PcdAcpiBasicMode,
and now we make it user-selectable. The default is a 3 GB limit.

Signed-off-by: Pete Batard <pete@akeo.ie>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

7 files changed, 134 insertions, 14 deletions

diff --git a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
index 2f48ca0d..964ca6d3 100644
--- a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
+++ b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
@@ -11,11 +11,13 @@
 #include <Library/AcpiLib.h>

 #include <Library/HiiLib.h>

 #include <Library/DebugLib.h>

+#include <Library/DxeServicesTableLib.h>

 #include <Library/IoLib.h>

 #include <Library/UefiBootServicesTableLib.h>

 #include <Library/UefiRuntimeServicesTableLib.h>

 #include <Library/DevicePathLib.h>

 #include <IndustryStandard/RpiMbox.h>

+#include <IndustryStandard/Bcm2711.h>

 #include <IndustryStandard/Bcm2836.h>

 #include <IndustryStandard/Bcm2836Gpio.h>

 #include <Library/GpioLib.h>

@@ -26,6 +28,8 @@ extern UINT8 ConfigDxeHiiBin[];
 extern UINT8 ConfigDxeStrings[];

 

 STATIC RASPBERRY_PI_FIRMWARE_PROTOCOL *mFwProtocol;

+STATIC UINT32 mModelFamily = 0;

+STATIC UINT32 mModelInstalledMB = 0;

 

 /*

  * The GUID inside Platform/RaspberryPi/RPi3/AcpiTables/AcpiTables.inf and

@@ -129,6 +133,24 @@ SetupVariables (
     PcdSet32 (PcdCustomCpuClock, PcdGet32 (PcdCustomCpuClock));

   }

 

+  if (mModelFamily >= 4 && mModelInstalledMB > 3 * 1024) {

+    /*

+     * This allows changing PcdRamLimitTo3GB in forms.

+     */

+    PcdSet32 (PcdRamMoreThan3GB, 1);

+

+    Size = sizeof (UINT32);

+    Status = gRT->GetVariable (L"RamLimitTo3GB",

+                               &gConfigDxeFormSetGuid,

+                               NULL, &Size, &Var32);

+    if (EFI_ERROR (Status)) {

+      PcdSet32 (PcdRamLimitTo3GB, PcdGet32 (PcdRamLimitTo3GB));

+    }

+  } else {

+    PcdSet32 (PcdRamMoreThan3GB, 0);

+    PcdSet32 (PcdRamLimitTo3GB, 0);

+  }

+

   Size = sizeof (UINT32);

   Status = gRT->GetVariable (L"SdIsArasan",

                   &gConfigDxeFormSetGuid,

@@ -224,7 +246,7 @@ ApplyVariables (
   UINT32 CpuClock = PcdGet32 (PcdCpuClock);

   UINT32 CustomCpuClock = PcdGet32 (PcdCustomCpuClock);

   UINT32 Rate = 0;

-  UINT32 ModelFamily = 0;

+  UINT64 SystemMemorySize;

 

   if (CpuClock != 0) {

     if (CpuClock == 2) {

@@ -258,15 +280,31 @@ ApplyVariables (
     DEBUG ((DEBUG_INFO, "Current CPU speed is %uHz\n", Rate));

   }

 

-  Status = mFwProtocol->GetModelFamily (&ModelFamily);

-  if (Status != EFI_SUCCESS) {

-    DEBUG ((DEBUG_ERROR, "Couldn't get the Raspberry Pi model family: %r\n", Status));

-  } else {

-    DEBUG ((DEBUG_INFO, "Current Raspberry Pi model family is 0x%x\n", ModelFamily));

-  }

+  if (mModelFamily >= 4 && PcdGet32 (PcdRamLimitTo3GB) == 0) {

+    /*

+     * Similar to how we compute the > 3 GB RAM segment's size in PlatformLib/

+     * RaspberryPiMem.c, with some overlap protection for the Bcm2xxx register

+     * spaces. This computation should also work for models with more than 4 GB

+     * RAM, if there ever exist ones.

+     */

+    SystemMemorySize = (UINT64)mModelInstalledMB * SIZE_1MB;

+    ASSERT (SystemMemorySize > 3UL * SIZE_1GB);

+    SystemMemorySize = MIN(SystemMemorySize, BCM2836_SOC_REGISTERS);

+    if (BCM2711_SOC_REGISTERS > 0) {

+      SystemMemorySize = MIN(SystemMemorySize, BCM2711_SOC_REGISTERS);

+    }

 

+    Status = gDS->AddMemorySpace (EfiGcdMemoryTypeSystemMemory, 3UL * BASE_1GB,

+                    SystemMemorySize - (3UL * SIZE_1GB),

+                    EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | EFI_MEMORY_WB);

+    ASSERT_EFI_ERROR (Status);

+    Status = gDS->SetMemorySpaceAttributes (3UL * BASE_1GB,

+                    SystemMemorySize - (3UL * SIZE_1GB),

+                    EFI_MEMORY_WB);

+    ASSERT_EFI_ERROR (Status);

+  }

 

-  if (ModelFamily == 3) {

+  if (mModelFamily == 3) {

     /*

      * Pi 3: either Arasan or SdHost goes to SD card.

      *

@@ -316,7 +354,7 @@ ApplyVariables (
     GpioPinFuncSet (52, Gpio48Group);

     GpioPinFuncSet (53, Gpio48Group);

 

-  } else if (ModelFamily == 4) {

+  } else if (mModelFamily == 4) {

     /*

      * Pi 4: either Arasan or eMMC2 goes to SD card.

      */

@@ -352,7 +390,7 @@ ApplyVariables (
       GpioPinFuncSet (39, GPIO_FSEL_ALT3);

     }

   } else {

-    DEBUG ((DEBUG_ERROR, "Model Family %d not supported...\n", ModelFamily));

+    DEBUG ((DEBUG_ERROR, "Model Family %d not supported...\n", mModelFamily));

   }

 

   /*

@@ -400,6 +438,20 @@ ConfigInitialize (
     return Status;

   }

 

+  Status = mFwProtocol->GetModelFamily (&mModelFamily);

+  if (Status != EFI_SUCCESS) {

+    DEBUG ((DEBUG_ERROR, "Couldn't get the Raspberry Pi model family: %r\n", Status));

+  } else {

+    DEBUG ((DEBUG_INFO, "Current Raspberry Pi model family is %d\n", mModelFamily));

+  }

+

+  Status = mFwProtocol->GetModelInstalledMB (&mModelInstalledMB);

+  if (Status != EFI_SUCCESS) {

+    DEBUG ((DEBUG_ERROR, "Couldn't get the Raspberry Pi installed RAM size: %r\n", Status));

+  } else {

+    DEBUG ((DEBUG_INFO, "Current Raspberry Pi installed RAM size is %d MB\n", mModelInstalledMB));

+  }

+

   Status = SetupVariables ();

   if (Status != EFI_SUCCESS) {

     DEBUG ((DEBUG_ERROR, "Couldn't not setup NV vars: %r\n", Status));

diff --git a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.inf b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.inf
index dc726cc6..407aac89 100644
--- a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.inf
+++ b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.inf
@@ -33,6 +33,7 @@
   ArmPlatformPkg/ArmPlatformPkg.dec

   MdePkg/MdePkg.dec

   MdeModulePkg/MdeModulePkg.dec

+  Silicon/Broadcom/Bcm27xx/Bcm27xx.dec

   Silicon/Broadcom/Bcm283x/Bcm283x.dec

   Platform/RaspberryPi/RaspberryPi.dec

   EmbeddedPkg/EmbeddedPkg.dec

@@ -53,10 +54,11 @@
   gConfigDxeFormSetGuid

 

 [Protocols]

-  gRaspberryPiFirmwareProtocolGuid ## CONSUMES

+  gRaspberryPiFirmwareProtocolGuid      ## CONSUMES

   gRaspberryPiConfigAppliedProtocolGuid ## PRODUCES

 

 [Pcd]

+  gBcm27xxTokenSpaceGuid.PcdBcm27xxRegistersAddress

   gBcm283xTokenSpaceGuid.PcdBcm283xRegistersAddress

   gRaspberryPiTokenSpaceGuid.PcdCpuClock

   gRaspberryPiTokenSpaceGuid.PcdCustomCpuClock

@@ -70,8 +72,8 @@
   gRaspberryPiTokenSpaceGuid.PcdDebugShowUEFIExit

   gRaspberryPiTokenSpaceGuid.PcdDisplayEnableScaledVModes

   gRaspberryPiTokenSpaceGuid.PcdDisplayEnableSShot

-

-[FeaturePcd]

+  gRaspberryPiTokenSpaceGuid.PcdRamMoreThan3GB

+  gRaspberryPiTokenSpaceGuid.PcdRamLimitTo3GB

 

 [Depex]

   gPcdProtocolGuid AND gRaspberryPiFirmwareProtocolGuid

diff --git a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.uni b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.uni
index 9b407663..830533a9 100644
--- a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.uni
+++ b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.uni
@@ -36,6 +36,17 @@
 #string STR_CHIPSET_SD_ARASAN        #language en-US "Arasan SDHCI"

 

 /*

+ * Advanced configuration.

+ */

+

+#string STR_ADVANCED_FORM_TITLE      #language en-US "Advanced Configuration"

+

+#string STR_ADVANCED_3GB_PROMPT      #language en-US "Limit RAM to 3 GB"

+#string STR_ADVANCED_3GB_HELP        #language en-US "OSes not supporting ACPI DMA constraints require a 3 GB limit or face broken xHCI USB"

+#string STR_ADVANCED_3GB_OFF         #language en-US "Disabled"

+#string STR_ADVANCED_3GB_ON          #language en-US "Enabled"

+

+/*

  * MMC/SD configuration.

  */

 

diff --git a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.vfr b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.vfr
index 60bfdbd4..483edd74 100644
--- a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.vfr
+++ b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxeHii.vfr
@@ -75,6 +75,18 @@ typedef struct {
 

 typedef struct {

   /*

+   * Always set by ConfigDxe prior to HII init to reflect

+   * platform capability.

+   */

+  UINT32 Supported;

+} ADVANCED_RAM_MORE_THAN_3GB_VARSTORE_DATA;

+

+typedef struct {

+  UINT32 Enabled;

+} ADVANCED_RAM_LIMIT_TO_3GB_VARSTORE_DATA;

+

+typedef struct {

+  /*

    * 0 - Don't disable multi-block.

    * 1 - Disable multi-block commands.

    */

@@ -140,6 +152,16 @@ formset
       name  = SdIsArasan,

       guid  = CONFIGDXE_FORM_SET_GUID;

 

+    efivarstore ADVANCED_RAM_MORE_THAN_3GB_VARSTORE_DATA,

+      attribute = EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,

+      name  = RamMoreThan3GB,

+      guid  = CONFIGDXE_FORM_SET_GUID;

+

+    efivarstore ADVANCED_RAM_LIMIT_TO_3GB_VARSTORE_DATA,

+      attribute = EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,

+      name  = RamLimitTo3GB,

+      guid  = CONFIGDXE_FORM_SET_GUID;

+

     efivarstore MMC_DISMULTI_VARSTORE_DATA,

       attribute = EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,

       name  = MmcDisableMulti,

@@ -193,6 +215,10 @@ formset
            prompt = STRING_TOKEN(STR_CHIPSET_FORM_TITLE),

            help = STRING_TOKEN(STR_NULL_STRING);

 

+        goto 0x1006,

+           prompt = STRING_TOKEN(STR_ADVANCED_FORM_TITLE),

+           help = STRING_TOKEN(STR_NULL_STRING);

+

         goto 0x1003,

            prompt = STRING_TOKEN(STR_MMC_FORM_TITLE),

            help = STRING_TOKEN(STR_NULL_STRING);

@@ -240,6 +266,21 @@ formset
         endoneof;

     endform;

 

+    form formid = 0x1006,

+        title  = STRING_TOKEN(STR_ADVANCED_FORM_TITLE);

+        subtitle text = STRING_TOKEN(STR_NULL_STRING);

+

+        grayoutif ideqval RamMoreThan3GB.Supported == 0;

+          oneof varid = RamLimitTo3GB.Enabled,

+              prompt      = STRING_TOKEN(STR_ADVANCED_3GB_PROMPT),

+              help        = STRING_TOKEN(STR_ADVANCED_3GB_HELP),

+              flags       = NUMERIC_SIZE_4 | INTERACTIVE | RESET_REQUIRED,

+              option text = STRING_TOKEN(STR_ADVANCED_3GB_OFF), value = 0, flags = DEFAULT;

+              option text = STRING_TOKEN(STR_ADVANCED_3GB_ON), value = 1, flags = 0;

+          endoneof;

+        endif;

+    endform;

+

     form formid = 0x1003,

         title  = STRING_TOKEN(STR_MMC_FORM_TITLE);

         subtitle text = STRING_TOKEN(STR_MMC_FORM_SUBTITLE);

diff --git a/Platform/RaspberryPi/RPi3/RPi3.dsc b/Platform/RaspberryPi/RPi3/RPi3.dsc
index df5b246a..48e1a32e 100644
--- a/Platform/RaspberryPi/RPi3/RPi3.dsc
+++ b/Platform/RaspberryPi/RPi3/RPi3.dsc
@@ -440,6 +440,12 @@
   gRaspberryPiTokenSpaceGuid.PcdDisplayEnableSShot|L"DisplayEnableSShot"|gConfigDxeFormSetGuid|0x0|1

 

   #

+  # Supporting > 3GB of memory.

+  #

+  gRaspberryPiTokenSpaceGuid.PcdRamMoreThan3GB|L"RamMoreThan3GB"|gConfigDxeFormSetGuid|0x0|0

+  gRaspberryPiTokenSpaceGuid.PcdRamLimitTo3GB|L"RamLimitTo3GB"|gConfigDxeFormSetGuid|0x0|0

+

+  #

   # Common UEFI ones.

   #

 

diff --git a/Platform/RaspberryPi/RPi4/RPi4.dsc b/Platform/RaspberryPi/RPi4/RPi4.dsc
index 60a5e38d..3ce2c3e4 100644
--- a/Platform/RaspberryPi/RPi4/RPi4.dsc
+++ b/Platform/RaspberryPi/RPi4/RPi4.dsc
@@ -478,6 +478,12 @@
   gRaspberryPiTokenSpaceGuid.PcdDisplayEnableSShot|L"DisplayEnableSShot"|gConfigDxeFormSetGuid|0x0|1

 

   #

+  # Supporting > 3GB of memory.

+  #

+  gRaspberryPiTokenSpaceGuid.PcdRamMoreThan3GB|L"RamMoreThan3GB"|gConfigDxeFormSetGuid|0x0|0

+  gRaspberryPiTokenSpaceGuid.PcdRamLimitTo3GB|L"RamLimitTo3GB"|gConfigDxeFormSetGuid|0x0|1

+

+  #

   # Common UEFI ones.

   #

 

diff --git a/Platform/RaspberryPi/RaspberryPi.dec b/Platform/RaspberryPi/RaspberryPi.dec
index bc378ffb..7f2c37ac 100644
--- a/Platform/RaspberryPi/RaspberryPi.dec
+++ b/Platform/RaspberryPi/RaspberryPi.dec
@@ -57,6 +57,8 @@
   gRaspberryPiTokenSpaceGuid.PcdCustomCpuClock|0|UINT32|0x00000016

   gRaspberryPiTokenSpaceGuid.PcdDisplayEnableScaledVModes|0|UINT8|0x00000017

   gRaspberryPiTokenSpaceGuid.PcdDisplayEnableSShot|0|UINT32|0x00000018

+  gRaspberryPiTokenSpaceGuid.PcdRamMoreThan3GB|0|UINT32|0x00000019

+  gRaspberryPiTokenSpaceGuid.PcdRamLimitTo3GB|0|UINT32|0x0000001A

 

 [PcdsFeatureFlag.common]

-  gRaspberryPiTokenSpaceGuid.PcdAcpiBasicMode|FALSE|BOOLEAN|0x00000019

+  gRaspberryPiTokenSpaceGuid.PcdAcpiBasicMode|FALSE|BOOLEAN|0x0000001B