[edk2-platforms][PATCH 0/3] Silicon/Broadcom/Bcm283x: RNG improvements

[edk2-platforms][PATCH 0/3] Silicon/Broadcom/Bcm283x: RNG improvements

[Pete Batard]

This patch series is targetted at adding support for the Bcm2838
Random Generator Driver, so that it can be used on the Raspberry
Pi 4.

Pete Batard (3):
  Silicon/Broadcom/Bcm283x: Rename Bcm2835 RNG driver
  Silicon/Broadcom/Bcm283x: Move Bcm2835 RNG defines to their own header
  Silicon/Broadcom/Bcm283x: Add Bcm2838 RNG driver

 Platform/RaspberryPi/RPi3/RPi3.dsc                                                      |   2 +-
 Platform/RaspberryPi/RPi3/RPi3.fdf                                                      |   2 +-
 Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c}     |  18 +-
 Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} |   6 +-
 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c                          | 285 ++++++++++++++++++++
 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf                        |  46 ++++
 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h                          |  22 ++
 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h                             |   9 -
 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h                          |  30 +++
 9 files changed, 397 insertions(+), 23 deletions(-)
 rename Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c} (93%)
 rename Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} (82%)
 create mode 100644 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c
 create mode 100644 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf
 create mode 100644 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
 create mode 100644 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h

-- 
2.21.0.windows.1

[edk2-platforms][PATCH 1/3] Silicon/Broadcom/Bcm283x: Rename Bcm2835 RNG driver

[Pete Batard]

The Bcm283x architecture provides multiple implementations of the
Random Number Generator, that have incompatibilities with one
another.

Because we will need to add a new driver for the Bcm2838 RNG we
rename the existing Bcm2835-compatible driver to Bcm2835RngDxe
and update the one platform that depends on this driver (RPi3).

We also rename the internal function calls from Bcm2836 to
Bcm2835 since, if we ever add platform support for Pi models
that use this SoC (original Pi, Pi Zero, etc), it may look
confusing to reference a feature that seems to belongs to the
next SoC iteration.

Signed-off-by: Pete Batard <pete@akeo.ie>
---
 Platform/RaspberryPi/RPi3/RPi3.dsc                                                      |  2 +-
 Platform/RaspberryPi/RPi3/RPi3.fdf                                                      |  2 +-
 Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c}     | 16 ++++++++--------
 Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} |  6 +++---
 4 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/Platform/RaspberryPi/RPi3/RPi3.dsc b/Platform/RaspberryPi/RPi3/RPi3.dsc
index 6a808b287ea9..945baa5021f8 100644
--- a/Platform/RaspberryPi/RPi3/RPi3.dsc
+++ b/Platform/RaspberryPi/RPi3/RPi3.dsc
@@ -602,7 +602,7 @@ [Components.common]
   #
   # RNG
   #
-  Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.inf
+  Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.inf
 
   #
   # UEFI application (Shell Embedded Boot Loader)
diff --git a/Platform/RaspberryPi/RPi3/RPi3.fdf b/Platform/RaspberryPi/RPi3/RPi3.fdf
index fd4e490fdcdf..31730865601f 100644
--- a/Platform/RaspberryPi/RPi3/RPi3.fdf
+++ b/Platform/RaspberryPi/RPi3/RPi3.fdf
@@ -273,7 +273,7 @@ [FV.FvMain]
   #
   # RNG
   #
-  INF Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.inf
+  INF Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.inf
 
   #
   # SCSI Bus and Disk Driver
diff --git a/Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.c b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
similarity index 93%
rename from Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.c
rename to Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
index 722815d32f06..ea86f9b3877e 100644
--- a/Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.c
+++ b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
@@ -1,6 +1,6 @@
 /** @file
 
-  This driver produces an EFI_RNG_PROTOCOL instance for the Broadcom 2836 RNG
+  This driver produces an EFI_RNG_PROTOCOL instance for the Broadcom 2835 RNG
 
   Copyright (C) 2019, Linaro Ltd. All rights reserved.<BR>
 
@@ -59,7 +59,7 @@
 STATIC
 EFI_STATUS
 EFIAPI
-Bcm2836RngGetInfo (
+Bcm2835RngGetInfo (
   IN      EFI_RNG_PROTOCOL        *This,
   IN OUT  UINTN                   *RNGAlgorithmListSize,
   OUT     EFI_RNG_ALGORITHM       *RNGAlgorithmList
@@ -116,7 +116,7 @@ Bcm2836RngGetInfo (
 STATIC
 EFI_STATUS
 EFIAPI
-Bcm2836RngGetRNG (
+Bcm2835RngGetRNG (
   IN EFI_RNG_PROTOCOL            *This,
   IN EFI_RNG_ALGORITHM           *RNGAlgorithm, OPTIONAL
   IN UINTN                       RNGValueLength,
@@ -168,9 +168,9 @@ Bcm2836RngGetRNG (
   return EFI_SUCCESS;
 }
 
-STATIC EFI_RNG_PROTOCOL mBcm2836RngProtocol = {
-  Bcm2836RngGetInfo,
-  Bcm2836RngGetRNG
+STATIC EFI_RNG_PROTOCOL mBcm2835RngProtocol = {
+  Bcm2835RngGetInfo,
+  Bcm2835RngGetRNG
 };
 
 //
@@ -178,7 +178,7 @@ STATIC EFI_RNG_PROTOCOL mBcm2836RngProtocol = {
 //
 EFI_STATUS
 EFIAPI
-Bcm2836RngEntryPoint (
+Bcm2835RngEntryPoint (
   IN EFI_HANDLE       ImageHandle,
   IN EFI_SYSTEM_TABLE *SystemTable
   )
@@ -186,7 +186,7 @@ Bcm2836RngEntryPoint (
   EFI_STATUS      Status;
 
   Status = gBS->InstallMultipleProtocolInterfaces (&ImageHandle,
-                  &gEfiRngProtocolGuid, &mBcm2836RngProtocol,
+                  &gEfiRngProtocolGuid, &mBcm2835RngProtocol,
                   NULL);
   ASSERT_EFI_ERROR (Status);
 
diff --git a/Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.inf b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.inf
similarity index 82%
rename from Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.inf
rename to Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.inf
index 8eb90de85cfd..dc91c1a9ba7b 100644
--- a/Silicon/Broadcom/Bcm283x/Drivers/RngDxe/RngDxe.inf
+++ b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.inf
@@ -9,14 +9,14 @@
 
 [Defines]
   INF_VERSION                    = 0x0001001B
-  BASE_NAME                      = RngDxe
+  BASE_NAME                      = Bcm2835RngDxe
   FILE_GUID                      = 9743084e-c82a-4714-b2ba-f571f81cb021
   MODULE_TYPE                    = DXE_DRIVER
   VERSION_STRING                 = 1.0
-  ENTRY_POINT                    = Bcm2836RngEntryPoint
+  ENTRY_POINT                    = Bcm2835RngEntryPoint
 
 [Sources]
-  RngDxe.c
+  Bcm2835RngDxe.c
 
 [Packages]
   MdePkg/MdePkg.dec
-- 
2.21.0.windows.1

[edk2-platforms][PATCH 2/3] Silicon/Broadcom/Bcm283x: Move Bcm2835 RNG defines to their own header

[Pete Batard]

While the Bcm2835 and Bcm2838 RNG appear to share the same register layout,
we prefer moving the RNG specific defines into their own header in case
this assertion doesn't hold true with future RNG drivers.

Also, this should make it clearer to see which specific elements apply to
which SoC implementation.

Signed-off-by: Pete Batard <pete@akeo.ie>
---
 Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c |  2 +-
 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h | 22 ++++++++++++++++++++
 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h    |  9 --------
 3 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
index ea86f9b3877e..84d194ea8472 100644
--- a/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
+++ b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
@@ -14,7 +14,7 @@
 #include <Library/IoLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 
-#include <IndustryStandard/Bcm2836.h>
+#include <IndustryStandard/Bcm2835Rng.h>
 
 #include <Protocol/Rng.h>
 
diff --git a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
new file mode 100644
index 000000000000..817c91cb24c1
--- /dev/null
+++ b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
@@ -0,0 +1,22 @@
+/** @file
+ *
+ *  Copyright (c) 2019, Pete Batard <pete@akeo.ie>.
+ *
+ *  SPDX-License-Identifier: BSD-2-Clause-Patent
+ *
+ **/
+
+#ifndef BCM2835_RNG_H__
+#define BCM2835_RNG_H__
+
+#define BCM2835_RNG_OFFSET                  0x00104000
+#define RNG_BASE_ADDRESS                    ((FixedPcdGet64 (PcdBcm283xRegistersAddress)) \
+                                            + BCM2835_RNG_OFFSET)
+
+#define RNG_CTRL                            (RNG_BASE_ADDRESS + 0x0)
+#define RNG_STATUS                          (RNG_BASE_ADDRESS + 0x4)
+#define RNG_DATA                            (RNG_BASE_ADDRESS + 0x8)
+
+#define RNG_CTRL_ENABLE                     0x1
+
+#endif /* BCM2835_RNG_H__ */
diff --git a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h
index 72c8e9dc4b14..02107086d439 100644
--- a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h
+++ b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h
@@ -50,13 +50,4 @@
 #define BCM2836_INTC_TIMER_CONTROL_OFFSET                   0x00000040
 #define BCM2836_INTC_TIMER_PENDING_OFFSET                   0x00000060
 
-/* random number generator */
-#define RNG_BASE_ADDRESS   (BCM2836_SOC_REGISTERS + 0x00104000)
-
-#define RNG_CTRL           (RNG_BASE_ADDRESS + 0x0)
-#define RNG_STATUS         (RNG_BASE_ADDRESS + 0x4)
-#define RNG_DATA           (RNG_BASE_ADDRESS + 0x8)
-
-#define RNG_CTRL_ENABLE    0x1
-
 #endif /*__BCM2836_H__ */
-- 
2.21.0.windows.1

[edk2-platforms][PATCH 3/3] Silicon/Broadcom/Bcm283x: Add Bcm2838 RNG driver

[Pete Batard]

This adds the Bcm2838 Random Number Generator Driver, which
is also the type of RNG that the Bmc2711-based Raspberry Pi 4
uses.

Signed-off-by: Pete Batard <pete@akeo.ie>
---
 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c   | 285 ++++++++++++++++++++
 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf |  46 ++++
 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h   |  30 +++
 3 files changed, 361 insertions(+)

diff --git a/Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c
new file mode 100644
index 000000000000..5737876e52c6
--- /dev/null
+++ b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c
@@ -0,0 +1,285 @@
+/** @file
+
+  This driver produces an EFI_RNG_PROTOCOL instance for the Broadcom 2838 RNG
+
+  Copyright (C) 2019, Pete Batard <pete@akeo.ie>
+  Copyright (C) 2019, Linaro Ltd. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+#include <Library/TimerLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+#include <IndustryStandard/Bcm2838Rng.h>
+
+#include <Protocol/Rng.h>
+
+#define RNG_WARMUP_COUNT        0x40000
+#define RNG_MAX_RETRIES         0x100         // arbitrary upper bound
+
+/**
+  Returns information about the random number generation implementation.
+
+  @param[in]     This                 A pointer to the EFI_RNG_PROTOCOL
+                                      instance.
+  @param[in,out] RNGAlgorithmListSize On input, the size in bytes of
+                                      RNGAlgorithmList.
+                                      On output with a return code of
+                                      EFI_SUCCESS, the size in bytes of the
+                                      data returned in RNGAlgorithmList. On
+                                      output with a return code of
+                                      EFI_BUFFER_TOO_SMALL, the size of
+                                      RNGAlgorithmList required to obtain the
+                                      list.
+  @param[out] RNGAlgorithmList        A caller-allocated memory buffer filled
+                                      by the driver with one EFI_RNG_ALGORITHM
+                                      element for each supported RNG algorithm.
+                                      The list must not change across multiple
+                                      calls to the same driver. The first
+                                      algorithm in the list is the default
+                                      algorithm for the driver.
+
+  @retval EFI_SUCCESS                 The RNG algorithm list was returned
+                                      successfully.
+  @retval EFI_UNSUPPORTED             The services is not supported by this
+                                      driver.
+  @retval EFI_DEVICE_ERROR            The list of algorithms could not be
+                                      retrieved due to a hardware or firmware
+                                      error.
+  @retval EFI_INVALID_PARAMETER       One or more of the parameters are
+                                      incorrect.
+  @retval EFI_BUFFER_TOO_SMALL        The buffer RNGAlgorithmList is too small
+                                      to hold the result.
+
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+Bcm2838RngGetInfo (
+  IN      EFI_RNG_PROTOCOL        *This,
+  IN OUT  UINTN                   *RNGAlgorithmListSize,
+  OUT     EFI_RNG_ALGORITHM       *RNGAlgorithmList
+  )
+{
+  if (This == NULL || RNGAlgorithmListSize == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (*RNGAlgorithmListSize < sizeof (EFI_RNG_ALGORITHM)) {
+    *RNGAlgorithmListSize = sizeof (EFI_RNG_ALGORITHM);
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  if (RNGAlgorithmList == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  *RNGAlgorithmListSize = sizeof (EFI_RNG_ALGORITHM);
+  CopyGuid (RNGAlgorithmList, &gEfiRngAlgorithmRaw);
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Read a single random value, in either FIFO or regular mode.
+
+  @param[in]  Val                     A pointer to the 32-bit word that is to
+                                      be filled with a random value.
+
+  @retval EFI_SUCCESS                 A random value was successfully read.
+  @retval EFI_NOT_READY               The number of retries elapsed before a
+                                      random value was generated.
+
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+Bcm2838RngReadValue (
+  IN OUT  UINT32                  *Val
+)
+{
+  UINT32 Avail;
+  UINT32 i;
+
+  ASSERT (Val != NULL);
+
+  Avail = MmioRead32 (RNG_FIFO_COUNT) & RNG_FIFO_DATA_AVAIL_MASK;
+
+  //
+  // If we don't have a value ready, wait 1 us and retry.
+  //
+  // Empirical testing on the platform this driver is designed to be used
+  // with shows that, unless you set a large divisor for the sample rate,
+  // random bits should be generated around the MHz frequency.
+  // Therefore a retry that doesn't expire until at least RNG_MAX_RETRIES
+  // microseconds should give us ample time to obtain a value. Besides,
+  // even outside of calling MicroSecondDelay (), we expect MMIO reads to
+  // be slow anyway...
+  //
+  // On the other hand, we may run into a timeout here if the warmup period
+  // has not been completed since the RNG locks RNG_FIFO_COUNT to zero
+  // until then. However, with the values we use for the target platform,
+  // (RPi4) you'd need to start requesting random data within the first
+  // 250 to 500 ms after driver instantiation for this to happen.
+  //
+  for (i = 0; Avail < 1 && i < RNG_MAX_RETRIES; i++) {
+    MicroSecondDelay (1);
+    Avail = MmioRead32 (RNG_FIFO_COUNT) & RNG_FIFO_DATA_AVAIL_MASK;
+  }
+  if (Avail < 1) {
+    return EFI_NOT_READY;
+  }
+
+  *Val = MmioRead32 (RNG_FIFO_DATA);
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Produces and returns an RNG value using either the default or specified RNG
+  algorithm.
+
+  @param[in]  This                    A pointer to the EFI_RNG_PROTOCOL
+                                      instance.
+  @param[in]  RNGAlgorithm            A pointer to the EFI_RNG_ALGORITHM that
+                                      identifies the RNG algorithm to use. May
+                                      be NULL in which case the function will
+                                      use its default RNG algorithm.
+  @param[in]  RNGValueLength          The length in bytes of the memory buffer
+                                      pointed to by RNGValue. The driver shall
+                                      return exactly this numbers of bytes.
+  @param[out] RNGValue                A caller-allocated memory buffer filled
+                                      by the driver with the resulting RNG
+                                      value.
+
+  @retval EFI_SUCCESS                 The RNG value was returned successfully.
+  @retval EFI_UNSUPPORTED             The algorithm specified by RNGAlgorithm
+                                      is not supported by this driver.
+  @retval EFI_DEVICE_ERROR            An RNG value could not be retrieved due
+                                      to a hardware or firmware error.
+  @retval EFI_NOT_READY               There is not enough random data available
+                                      to satisfy the length requested by
+                                      RNGValueLength.
+  @retval EFI_INVALID_PARAMETER       RNGValue is NULL or RNGValueLength is
+                                      zero.
+
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+Bcm2838RngGetRNG (
+  IN EFI_RNG_PROTOCOL            *This,
+  IN EFI_RNG_ALGORITHM           *RNGAlgorithm, OPTIONAL
+  IN UINTN                       RNGValueLength,
+  OUT UINT8                      *RNGValue
+  )
+{
+  EFI_STATUS      Status;
+  UINT32          Val;
+
+  if (This == NULL || RNGValueLength == 0 || RNGValue == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // We only support the raw algorithm, so reject requests for anything else
+  //
+  if (RNGAlgorithm != NULL &&
+      !CompareGuid (RNGAlgorithm, &gEfiRngAlgorithmRaw)) {
+    return EFI_UNSUPPORTED;
+  }
+
+  //
+  // The Linux driver from Broadcom checks RNG_BIT_COUNT here to ensure that
+  // the warmup threshold has been reached, but our testing shows that this is
+  // pointless as RNG_BIT_COUNT is increased even during warmup and, as long
+  // as warmup isn't complete, the FIFO reports that no values are available.
+  //
+  // Also note that RNG_BIT_COUNT doesn't roll over. Once it reaches 0xFFFFFFFF
+  // it just stays there...
+  //
+
+  while (RNGValueLength >= sizeof (UINT32)) {
+    Status = Bcm2838RngReadValue (&Val);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+    WriteUnaligned32 ((VOID *)RNGValue, Val);
+    RNGValue += sizeof (UINT32);
+    RNGValueLength -= sizeof (UINT32);
+  }
+
+  if (RNGValueLength > 0) {
+    Status = Bcm2838RngReadValue (&Val);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+    while (RNGValueLength--) {
+      *RNGValue++ = (UINT8)Val;
+      Val >>= 8;
+    }
+  }
+  return EFI_SUCCESS;
+}
+
+STATIC EFI_RNG_PROTOCOL mBcm2838RngProtocol = {
+  Bcm2838RngGetInfo,
+  Bcm2838RngGetRNG
+};
+
+//
+// Entry point of this driver.
+//
+EFI_STATUS
+EFIAPI
+Bcm2838RngEntryPoint (
+  IN EFI_HANDLE       ImageHandle,
+  IN EFI_SYSTEM_TABLE *SystemTable
+  )
+{
+  EFI_STATUS      Status;
+
+  Status = gBS->InstallMultipleProtocolInterfaces (&ImageHandle,
+                  &gEfiRngProtocolGuid, &mBcm2838RngProtocol,
+                  NULL);
+  ASSERT_EFI_ERROR (Status);
+
+  //
+  // Set the warm up bit count.
+  //
+  // This results in the RNG holding off from populating any value into the
+  // FIFO until the value below has been reached in RNG_BIT_COUNT.
+  //
+  MmioWrite32 (RNG_BIT_COUNT_THRESHOLD, RNG_WARMUP_COUNT);
+
+  //
+  // We would disable RNG interrupts here... if we had access to the datasheet.
+  //
+
+  //
+  // Enable the RNG with a sample rate divisor of 3.
+  //
+  // For a Bcm2711 running at 1.5 GHz, this should generate random bits at a
+  // rate of about 1 every microsecond (1 MHz).
+  //
+  // Note that The divisor is a power of two index, meaning that each
+  // consecutive divisor halves the frequency at which bits are being
+  // produced. Zero is a special value that seems to set the rate somewhere
+  // between divisors 1 and 2.
+  //
+  // Also note that Broadcom set the whole ENABLE_MASK in the Linux driver,
+  // instead of single bits, which may be unintended. But since we don't have
+  // any public documentation on what each of these bits do, we follow suit.
+  //
+  MmioWrite32 (RNG_CTRL,
+    RNG_CTRL_ENABLE_MASK | (3 << RNG_CTRL_SAMPLE_RATE_DIVISOR_SHIFT));
+
+  return EFI_SUCCESS;
+}
diff --git a/Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf
new file mode 100644
index 000000000000..fdc1b25743cf
--- /dev/null
+++ b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf
@@ -0,0 +1,46 @@
+#/** @file
+#
+#  Copyright (c) 2019, Pete Batard <pete@akeo.ie>
+#  Copyright (c) 2019, ARM Limited. All rights reserved.
+#  Copyright (c) 2019, Linaro, Ltd. All rights reserved.
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+#**/
+
+[Defines]
+  INF_VERSION                    = 0x0001001B
+  BASE_NAME                      = Bcm2838RngDxe
+  FILE_GUID                      = 5ec564ce-b656-435c-a652-5cb719784542
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = Bcm2838RngEntryPoint
+
+[Sources]
+  Bcm2838RngDxe.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  Silicon/Broadcom/Bcm283x/Bcm283x.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  IoLib
+  PcdLib
+  TimerLib
+  UefiBootServicesTableLib
+  UefiDriverEntryPoint
+
+[Protocols]
+  gEfiRngProtocolGuid              ## PRODUCES
+
+[Guids]
+  gEfiRngAlgorithmRaw
+
+[FixedPcd]
+  gBcm283xTokenSpaceGuid.PcdBcm283xRegistersAddress
+
+[Depex]
+  TRUE
diff --git a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h
new file mode 100644
index 000000000000..003866fa866e
--- /dev/null
+++ b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h
@@ -0,0 +1,30 @@
+/** @file
+ *
+ *  Copyright (c) 2019, Pete Batard <pete@akeo.ie>
+ *
+ *  SPDX-License-Identifier: BSD-2-Clause-Patent
+ *
+ **/
+
+#ifndef BCM2838_RNG_H__
+#define BCM2838_RNG_H__
+
+#define BCM2838_RNG_OFFSET                  0x00104000
+#define RNG_BASE_ADDRESS                    ((FixedPcdGet64 (PcdBcm283xRegistersAddress)) \
+                                            + BCM2838_RNG_OFFSET)
+
+#define RNG_CTRL                            (RNG_BASE_ADDRESS + 0x0)
+#define RNG_STATUS                          (RNG_BASE_ADDRESS + 0x4)
+#define RNG_DATA                            (RNG_BASE_ADDRESS + 0x8)
+#define RNG_BIT_COUNT                       (RNG_BASE_ADDRESS + 0xc)
+#define RNG_BIT_COUNT_THRESHOLD             (RNG_BASE_ADDRESS + 0x10)
+#define RNG_INT_STATUS                      (RNG_BASE_ADDRESS + 0x18)
+#define RNG_INT_ENABLE                      (RNG_BASE_ADDRESS + 0x1c)
+#define RNG_FIFO_DATA                       (RNG_BASE_ADDRESS + 0x20)
+#define RNG_FIFO_COUNT                      (RNG_BASE_ADDRESS + 0x24)
+
+#define RNG_CTRL_ENABLE_MASK                0x1fff
+#define RNG_CTRL_SAMPLE_RATE_DIVISOR_SHIFT  13      // Unmasked bits from above
+#define RNG_FIFO_DATA_AVAIL_MASK            0xff
+
+#endif /* BCM2838_RNG_H__ */
-- 
2.21.0.windows.1

Re: [edk2-platforms][PATCH 1/3] Silicon/Broadcom/Bcm283x: Rename Bcm2835 RNG driver

[Philippe Mathieu-Daudé]

On 12/2/19 12:55 PM, Pete Batard wrote:
> The Bcm283x architecture provides multiple implementations of the
> Random Number Generator, that have incompatibilities with one
> another.
> 
> Because we will need to add a new driver for the Bcm2838 RNG we
> rename the existing Bcm2835-compatible driver to Bcm2835RngDxe
> and update the one platform that depends on this driver (RPi3).
> 
> We also rename the internal function calls from Bcm2836 to
> Bcm2835 since, if we ever add platform support for Pi models
> that use this SoC (original Pi, Pi Zero, etc), it may look
> confusing to reference a feature that seems to belongs to the
> next SoC iteration.
> 
> Signed-off-by: Pete Batard <pete@akeo.ie>
> ---
>   Platform/RaspberryPi/RPi3/RPi3.dsc                                                      |  2 +-
>   Platform/RaspberryPi/RPi3/RPi3.fdf                                                      |  2 +-
>   Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c}     | 16 ++++++++--------
>   Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} |  6 +++---
>   4 files changed, 13 insertions(+), 13 deletions(-)

Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

Re: [edk2-platforms][PATCH 2/3] Silicon/Broadcom/Bcm283x: Move Bcm2835 RNG defines to their own header

[Philippe Mathieu-Daudé]

On 12/2/19 12:55 PM, Pete Batard wrote:
> While the Bcm2835 and Bcm2838 RNG appear to share the same register layout,
> we prefer moving the RNG specific defines into their own header in case
> this assertion doesn't hold true with future RNG drivers.
> 
> Also, this should make it clearer to see which specific elements apply to
> which SoC implementation.
> 
> Signed-off-by: Pete Batard <pete@akeo.ie>
> ---
>   Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c |  2 +-
>   Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h | 22 ++++++++++++++++++++
>   Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h    |  9 --------
>   3 files changed, 23 insertions(+), 10 deletions(-)
> 
> diff --git a/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
> index ea86f9b3877e..84d194ea8472 100644
> --- a/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
> +++ b/Silicon/Broadcom/Bcm283x/Drivers/Bcm2835RngDxe/Bcm2835RngDxe.c
> @@ -14,7 +14,7 @@
>   #include <Library/IoLib.h>
>   #include <Library/UefiBootServicesTableLib.h>
>   
> -#include <IndustryStandard/Bcm2836.h>
> +#include <IndustryStandard/Bcm2835Rng.h>
>   
>   #include <Protocol/Rng.h>
>   
> diff --git a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
> new file mode 100644
> index 000000000000..817c91cb24c1
> --- /dev/null
> +++ b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
> @@ -0,0 +1,22 @@
> +/** @file
> + *
> + *  Copyright (c) 2019, Pete Batard <pete@akeo.ie>.
> + *
> + *  SPDX-License-Identifier: BSD-2-Clause-Patent
> + *
> + **/
> +
> +#ifndef BCM2835_RNG_H__
> +#define BCM2835_RNG_H__
> +
> +#define BCM2835_RNG_OFFSET                  0x00104000
> +#define RNG_BASE_ADDRESS                    ((FixedPcdGet64 (PcdBcm283xRegistersAddress)) \
> +                                            + BCM2835_RNG_OFFSET)
> +
> +#define RNG_CTRL                            (RNG_BASE_ADDRESS + 0x0)
> +#define RNG_STATUS                          (RNG_BASE_ADDRESS + 0x4)
> +#define RNG_DATA                            (RNG_BASE_ADDRESS + 0x8)
> +
> +#define RNG_CTRL_ENABLE                     0x1
> +
> +#endif /* BCM2835_RNG_H__ */
> diff --git a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h
> index 72c8e9dc4b14..02107086d439 100644
> --- a/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h
> +++ b/Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h
> @@ -50,13 +50,4 @@
>   #define BCM2836_INTC_TIMER_CONTROL_OFFSET                   0x00000040
>   #define BCM2836_INTC_TIMER_PENDING_OFFSET                   0x00000060
>   
> -/* random number generator */
> -#define RNG_BASE_ADDRESS   (BCM2836_SOC_REGISTERS + 0x00104000)
> -
> -#define RNG_CTRL           (RNG_BASE_ADDRESS + 0x0)
> -#define RNG_STATUS         (RNG_BASE_ADDRESS + 0x4)
> -#define RNG_DATA           (RNG_BASE_ADDRESS + 0x8)
> -
> -#define RNG_CTRL_ENABLE    0x1
> -
>   #endif /*__BCM2836_H__ */
> 

Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

Re: [edk2-platforms][PATCH 0/3] Silicon/Broadcom/Bcm283x: RNG improvements

[Ard Biesheuvel]

On Mon, 2 Dec 2019 at 11:55, Pete Batard <pete@akeo.ie> wrote:
>
> This patch series is targetted at adding support for the Bcm2838
> Random Generator Driver, so that it can be used on the Raspberry
> Pi 4.
>
> Pete Batard (3):
>   Silicon/Broadcom/Bcm283x: Rename Bcm2835 RNG driver
>   Silicon/Broadcom/Bcm283x: Move Bcm2835 RNG defines to their own header
>   Silicon/Broadcom/Bcm283x: Add Bcm2838 RNG driver
>

Thanks for respinning this. For the series,

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

I have pushed all three patches, but going forward, can we keep
patches for new hardware together with patches that add the platform?
There is currently no way to build test the new driver introduced in
#3.

Pushed as 8e75ee0c9653..d6b7f67e62da



>  Platform/RaspberryPi/RPi3/RPi3.dsc                                                      |   2 +-
>  Platform/RaspberryPi/RPi3/RPi3.fdf                                                      |   2 +-
>  Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c}     |  18 +-
>  Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} |   6 +-
>  Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c                          | 285 ++++++++++++++++++++
>  Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf                        |  46 ++++
>  Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h                          |  22 ++
>  Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h                             |   9 -
>  Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h                          |  30 +++
>  9 files changed, 397 insertions(+), 23 deletions(-)
>  rename Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c} (93%)
>  rename Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} (82%)
>  create mode 100644 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c
>  create mode 100644 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf
>  create mode 100644 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
>  create mode 100644 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h
>
> --
> 2.21.0.windows.1
>

Re: [edk2-devel] [edk2-platforms][PATCH 0/3] Silicon/Broadcom/Bcm283x: RNG improvements

[Pete Batard]

Hi Ard,


On 2019.12.02 16:03, Ard Biesheuvel wrote:
> On Mon, 2 Dec 2019 at 11:55, Pete Batard <pete@akeo.ie> wrote:
>>
>> This patch series is targetted at adding support for the Bcm2838
>> Random Generator Driver, so that it can be used on the Raspberry
>> Pi 4.
>>
>> Pete Batard (3):
>>    Silicon/Broadcom/Bcm283x: Rename Bcm2835 RNG driver
>>    Silicon/Broadcom/Bcm283x: Move Bcm2835 RNG defines to their own header
>>    Silicon/Broadcom/Bcm283x: Add Bcm2838 RNG driver
>>
> 
> Thanks for respinning this. For the series,
> 
> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> 
> I have pushed all three patches,

Thanks.

> but going forward, can we keep
> patches for new hardware together with patches that add the platform?

Yeah, I thought about only sending 3/3 until after we had the basics of 
the RPi4 platform in, but didn't see it as that big a deal to just send 
this whole thing as a set, since it does make sense to have all the 
Broadcom RNG related change grouped.

In case this is your concern, it's always been my plan to only start 
sending PCIe/xHCI related patches until after we have some of the basic 
platform in, so you won't be seeing any new Pi4-only changes at this 
stage, without them also being part of a set that allows testing.

Regards,

/Pete

> There is currently no way to build test the new driver introduced in
> #3.
> 
> Pushed as 8e75ee0c9653..d6b7f67e62da
> 
> 
> 
>>   Platform/RaspberryPi/RPi3/RPi3.dsc                                                      |   2 +-
>>   Platform/RaspberryPi/RPi3/RPi3.fdf                                                      |   2 +-
>>   Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c}     |  18 +-
>>   Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} |   6 +-
>>   Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c                          | 285 ++++++++++++++++++++
>>   Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf                        |  46 ++++
>>   Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h                          |  22 ++
>>   Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2836.h                             |   9 -
>>   Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h                          |  30 +++
>>   9 files changed, 397 insertions(+), 23 deletions(-)
>>   rename Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.c => Bcm2835RngDxe/Bcm2835RngDxe.c} (93%)
>>   rename Silicon/Broadcom/Bcm283x/Drivers/{RngDxe/RngDxe.inf => Bcm2835RngDxe/Bcm2835RngDxe.inf} (82%)
>>   create mode 100644 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.c
>>   create mode 100644 Silicon/Broadcom/Bcm283x/Drivers/Bcm2838RngDxe/Bcm2838RngDxe.inf
>>   create mode 100644 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2835Rng.h
>>   create mode 100644 Silicon/Broadcom/Bcm283x/Include/IndustryStandard/Bcm2838Rng.h
>>
>> --
>> 2.21.0.windows.1
>>
> 
> 
>