Re: [edk2] [PATCH edk2-platforms v2 1/7] Silicon/Atmel: add support for AtSha204a RNG

[Ard Biesheuvel]

On 22 February 2018 at 13:08, Leif Lindholm  wrote:
> On Tue, Feb 20, 2018 at 05:49:38PM +, Ard Biesheuvel wrote:
>> This adds support for using the random number generator in the Atmel
>> AtSha204a over I2C. Other functionality of the chip is currently
>> unsupported.
>>
>> Note that the the I2C support in this device essentially violates the
>> protocol layering, by requiring that the device is woken up by driving
>> SDA low for a certain amount of time, which is something that cannot be
>> expressed in terms of an I2C packet sent to the device's slave address.
>> Instead, the slave address 0x0 is added to the device's address array,
>> and the wake is sent by sending a dummy write to address 0x0, and
>> ignoring the subsequent error. This requires the I2C bus to be clocked
>> at 100 kHz.
>>
>> Contributed-under: TianoCore Contribution Agreement 1.1
>> Signed-off-by: Ard Biesheuvel 
>
> All of my feedback from v1 has been addressed, so:
> Reviewed-by: Leif Lindholm 

Thanks.

Pushed as 487015fb23c1a40f0d05240cadde4faf979483ee
___
edk2-devel mailing list
edk2-devel@lists.01.org
https://lists.01.org/mailman/listinfo/edk2-devel

Re: [edk2] [PATCH edk2-platforms v2 1/7] Silicon/Atmel: add support for AtSha204a RNG

[Leif Lindholm]

On Tue, Feb 20, 2018 at 05:49:38PM +, Ard Biesheuvel wrote:
> This adds support for using the random number generator in the Atmel
> AtSha204a over I2C. Other functionality of the chip is currently
> unsupported.
> 
> Note that the the I2C support in this device essentially violates the
> protocol layering, by requiring that the device is woken up by driving
> SDA low for a certain amount of time, which is something that cannot be
> expressed in terms of an I2C packet sent to the device's slave address.
> Instead, the slave address 0x0 is added to the device's address array,
> and the wake is sent by sending a dummy write to address 0x0, and
> ignoring the subsequent error. This requires the I2C bus to be clocked
> at 100 kHz.
> 
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Ard Biesheuvel 

All of my feedback from v1 has been addressed, so:
Reviewed-by: Leif Lindholm 
___
edk2-devel mailing list
edk2-devel@lists.01.org
https://lists.01.org/mailman/listinfo/edk2-devel

[edk2] [PATCH edk2-platforms v2 1/7] Silicon/Atmel: add support for AtSha204a RNG

[Ard Biesheuvel]

This adds support for using the random number generator in the Atmel
AtSha204a over I2C. Other functionality of the chip is currently
unsupported.

Note that the the I2C support in this device essentially violates the
protocol layering, by requiring that the device is woken up by driving
SDA low for a certain amount of time, which is something that cannot be
expressed in terms of an I2C packet sent to the device's slave address.
Instead, the slave address 0x0 is added to the device's address array,
and the wake is sent by sending a dummy write to address 0x0, and
ignoring the subsequent error. This requires the I2C bus to be clocked
at 100 kHz.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel 
---
 Silicon/Atmel/AtSha204a/AtSha204a.dec |  22 ++
 Silicon/Atmel/AtSha204a/AtSha204aDriver.c | 309 
 Silicon/Atmel/AtSha204a/AtSha204aDriver.h |  81 +
 Silicon/Atmel/AtSha204a/AtSha204aDxe.inf  |  52 
 Silicon/Atmel/AtSha204a/ComponentName.c   | 186 
 Silicon/Atmel/AtSha204a/DriverBinding.c   | 242 +++
 6 files changed, 892 insertions(+)

diff --git a/Silicon/Atmel/AtSha204a/AtSha204a.dec 
b/Silicon/Atmel/AtSha204a/AtSha204a.dec
new file mode 100644
index ..f1fdea59843d
--- /dev/null
+++ b/Silicon/Atmel/AtSha204a/AtSha204a.dec
@@ -0,0 +1,22 @@
+## @file
+#
+#  Copyright (c) 2018, Linaro Ltd. All rights reserved.
+#
+#  This program and the accompanying materials
+#  are licensed and made available under the terms and conditions of the BSD 
License
+#  which accompanies this distribution.  The full text of the license may be 
found at
+#  http://opensource.org/licenses/bsd-license.php
+#
+#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR 
IMPLIED.
+#
+##
+
+[Defines]
+  DEC_SPECIFICATION  = 0x0001001A
+  PACKAGE_NAME   = AtSha204a
+  PACKAGE_GUID   = 86085a5b-355b-4e72-92ab-fc3e1d71c9ad
+  PACKAGE_VERSION= 0.1
+
+[Guids]
+  gAtSha204aI2cDeviceGuid = { 0x52e9b64b, 0x4ec1, 0x4bd6, { 0x9e, 0x1c, 0x6d, 
0xac, 0xef, 0x35, 0x18, 0x21 } }
diff --git a/Silicon/Atmel/AtSha204a/AtSha204aDriver.c 
b/Silicon/Atmel/AtSha204a/AtSha204aDriver.c
new file mode 100644
index ..5db2de21a731
--- /dev/null
+++ b/Silicon/Atmel/AtSha204a/AtSha204aDriver.c
@@ -0,0 +1,309 @@
+/** @file
+  Device driver for the Atmel ATSHA204A random number generator.
+
+  Copyright (c) 2018, Linaro Ltd. All rights reserved.
+
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD
+  License which accompanies this distribution. The full text of the license may
+  be found at  http://opensource.org/licenses/bsd-license.php.
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "AtSha204aDriver.h"
+
+#include 
+#include 
+#include 
+
+#define MAX_RETRIES 5
+
+// Don't bother calculating the CRC for the immutable RANDOM opcode packet
+#define OPCODE_COMMAND_PACKET_CRC   0xcd24
+
+/**
+  Returns information about the random number generation implementation.
+
+  @param[in] This   A pointer to the EFI_RNG_PROTOCOL instance.
+  @param[in,out] AlgorithmListSize  On input, the size in bytes of 
AlgorithmList
+On output with a return code of 
EFI_SUCCESS,
+the size in bytes of the data returned in
+AlgorithmList. On output with a return
+code of EFI_BUFFER_TOO_SMALL, the size of
+AlgorithmList required to obtain the list.
+  @param[out] AlgorithmList 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