From: Leif Lindholm <leif.lindholm@linaro.org>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: edk2-devel@lists.01.org, joakim.bech@linaro.org
Subject: Re: [PATCH] Silicon/Atmel: add support for AtSha204a RNG
Date: Mon, 19 Feb 2018 17:28:48 +0000 [thread overview]
Message-ID: <20180219172848.gl33dx5aafy3hcp6@bivouac.eciton.net> (raw)
In-Reply-To: <20180219094332.19853-1-ard.biesheuvel@linaro.org>
On Mon, Feb 19, 2018 at 09:43:32AM +0000, 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.
As long as the violation is down to the component rather than its
integration onto the mezzanine board, I see no problem with this.
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
> Silicon/Atmel/AtSha204a/AtSha204a.dec | 22 ++
> Silicon/Atmel/AtSha204a/AtSha204aDriver.c | 308 ++++++++++++++++++++
> 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, 891 insertions(+)
>
> diff --git a/Silicon/Atmel/AtSha204a/AtSha204a.dec b/Silicon/Atmel/AtSha204a/AtSha204a.dec
> new file mode 100644
> index 000000000000..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 000000000000..25329086592a
> --- /dev/null
> +++ b/Silicon/Atmel/AtSha204a/AtSha204aDriver.c
> @@ -0,0 +1,308 @@
> +/** @file
> + Device driver for the Atmel ATSHA204A random number generator.
> +
> + Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
> +
> + 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 <Library/BaseMemoryLib.h>
> +#include <Library/DebugLib.h>
> +#include <Library/MemoryAllocationLib.h>
> +
> +#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 too small to
> + hold the result.
> +
> +**/
> +STATIC
> +EFI_STATUS
> +EFIAPI
> +AtSha240aGetInfo (
> + IN EFI_RNG_PROTOCOL *This,
> + IN OUT UINTN *AlgorithmListSize,
> + OUT EFI_RNG_ALGORITHM *AlgorithmList
> +)
> +{
> + UINTN Size;
> +
> + //
> + // We only implement the raw algorithm
> + //
> + Size = sizeof gEfiRngAlgorithmRaw;
Use parantheses for sizeof?
Also, can this be different from sizeof (EFI_GUID)?
> +
> + if (*AlgorithmListSize < Size) {
> + *AlgorithmListSize = Size;
> + return EFI_BUFFER_TOO_SMALL;
> + }
> +
> + gBS->CopyMem (AlgorithmList, &gEfiRngAlgorithmRaw, Size);
You already pull in BaseMemoryLib, so could use CopyGuid?
> + *AlgorithmListSize = Size;
> +
> + 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] Algorithm 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] ValueLength The length in bytes of the memory buffer
> + pointed to by RNGValue. The driver shall
> + return exactly this numbers of bytes.
> + @param[out] Value 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
> +AtSha240aGetRNG (
> + IN EFI_RNG_PROTOCOL *This,
> + IN EFI_RNG_ALGORITHM *Algorithm OPTIONAL,
> + IN UINTN ValueLength,
> + OUT UINT8 *Value
> +)
> +{
> + EFI_STATUS Status;
> + ATSHA204A_DEV *AtSha204a;
> + ATSHA204A_I2C_RNG_COMMAND Cmd;
> + ATSHA204A_I2C_RNG_RESULT Res;
> + I2C_RNG_REQUEST Req;
> + I2C_RNG_REQUEST Resp;
Since I just gave Marcin a hard time over non-approved abbreviations,
I should probably flag these too... Would you mind terribly turning
them into Command, Result, Request, Response?
> + UINTN Retries;
> +
> + if (Algorithm != NULL && !CompareGuid (Algorithm, &gEfiRngAlgorithmRaw)) {
> + return EFI_UNSUPPORTED;
> + }
> +
> + AtSha204a = ATSHA204A_DEV_FROM_THIS (This);
> +
> + Req.OperationCount = 1;
> + Req.Operation.Flags = 0;
> +
> + Cmd.Command = ATSHA204A_COMMAND;
> + Cmd.Count = sizeof (Cmd) - 1;
> + Cmd.Opcode = ATSHA204A_OPCODE_RANDOM;
> + Cmd.Param1 = 0;
> + Cmd.Param2 = 0;
> + Cmd.Crc = OPCODE_COMMAND_PACKET_CRC;
> +
> + Resp.OperationCount = 1;
> + Resp.Operation.Flags = I2C_FLAG_READ;
> + Resp.Operation.LengthInBytes = sizeof (Res);
> + Resp.Operation.Buffer = (VOID *)&Res;
> +
> + Retries = 0;
> + while (ValueLength > 0) {
> + //
> + // The AtSha204a will go back to sleep right in the middle of a transaction
> + // if it does not complete in ~1.3 seconds. So send the wake sequence for
> + // each iteration, which consists of a dummy write to slave address 0x0.
> + //
> + Req.Operation.LengthInBytes = 0;
> + Status = AtSha204a->I2cIo->QueueRequest (AtSha204a->I2cIo, 1, NULL,
> + (VOID *)&Req, NULL);
> + DEBUG ((DEBUG_INFO, "%a: wake AtSha204a: I2cIo->QueueRequest() - %r\n",
> + __FUNCTION__, Status));
> +
> + gBS->Stall (2500); // wait 2.5 ms for wake to complete
> +
> + Req.Operation.LengthInBytes = sizeof (Cmd);
> + Req.Operation.Buffer = (VOID *)&Cmd;
> + Status = AtSha204a->I2cIo->QueueRequest (AtSha204a->I2cIo, 0, NULL,
> + (VOID *)&Req, NULL);
> + if (EFI_ERROR (Status)) {
> + if (++Retries <= MAX_RETRIES) {
> + continue;
> + }
> + DEBUG ((DEBUG_ERROR, "%a: I2C request transfer failed, Status == %r\n",
> + __FUNCTION__, Status));
> + return EFI_DEVICE_ERROR;
> + }
> +
> + gBS->Stall (50 * 1000); // 50 ms max execution time for RANDOM opcode
Is there no way of polling for response complete?
50ms per iteration?? :( (or, well, 52.5 in total)
/
Leif
> +
> + Status = AtSha204a->I2cIo->QueueRequest (AtSha204a->I2cIo, 0, NULL,
> + (VOID *)&Resp, NULL);
> + if (EFI_ERROR (Status)) {
> + if (++Retries <= MAX_RETRIES) {
> + continue;
> + }
> + DEBUG ((DEBUG_ERROR, "%a: I2C response transfer failed, Status == %r\n",
> + __FUNCTION__, Status));
> + return EFI_DEVICE_ERROR;
> + }
> +
> + if (Res.Count < sizeof (Res)) {
> + //
> + // Incomplete packet received, most likely due to an error. Retry.
> + //
> + if (++Retries <= MAX_RETRIES) {
> + continue;
> + }
> + DEBUG ((DEBUG_WARN, "%a: incomplete packet received\n", __FUNCTION__));
> + return EFI_DEVICE_ERROR;
> + }
> +
> + gBS->CopyMem (Value, Res.Result, MIN (ValueLength, ATSHA204A_OUTPUT_SIZE));
> + if (ValueLength < ATSHA204A_OUTPUT_SIZE) {
> + break;
> + }
> +
> + Value += ATSHA204A_OUTPUT_SIZE;
> + ValueLength -= ATSHA204A_OUTPUT_SIZE;
> + Retries = 0;
> + }
> + return EFI_SUCCESS;
> +}
> +
> +EFI_STATUS
> +AtSha204aInit (
> + IN EFI_HANDLE DriverBindingHandle,
> + IN EFI_HANDLE ControllerHandle
> + )
> +{
> + EFI_STATUS Status;
> + ATSHA204A_DEV *AtSha204a;
> +
> + Status = gBS->AllocatePool (EfiBootServicesData, sizeof (ATSHA204A_DEV),
> + (VOID **) &AtSha204a);
> + if (EFI_ERROR (Status)) {
> + return EFI_OUT_OF_RESOURCES;
> + }
> +
> + AtSha204a->Signature = ATSHA204A_DEV_SIGNATURE;
> + AtSha204a->Rng.GetInfo = AtSha240aGetInfo;
> + AtSha204a->Rng.GetRNG = AtSha240aGetRNG;
> +
> + //
> + // Open I2C I/O Protocol
> + //
> + Status = gBS->OpenProtocol (ControllerHandle,
> + &gEfiI2cIoProtocolGuid,
> + (VOID **)&AtSha204a->I2cIo,
> + DriverBindingHandle,
> + ControllerHandle,
> + EFI_OPEN_PROTOCOL_BY_DRIVER);
> + if (EFI_ERROR (Status)) {
> + goto ErrorFreeDev;
> + }
> +
> + Status = gBS->InstallProtocolInterface (&ControllerHandle,
> + &gEfiRngProtocolGuid,
> + EFI_NATIVE_INTERFACE,
> + &AtSha204a->Rng);
> + if (EFI_ERROR (Status)) {
> + DEBUG ((DEBUG_ERROR,
> + "Failed to install RNG protocol interface (Status == %r)\n",
> + Status));
> + goto ErrorCloseProtocol;
> + }
> +
> + return EFI_SUCCESS;
> +
> +ErrorCloseProtocol:
> + gBS->CloseProtocol (ControllerHandle, &gEfiI2cIoProtocolGuid,
> + DriverBindingHandle, ControllerHandle);
> +
> +ErrorFreeDev:
> + gBS->FreePool (AtSha204a);
> +
> + return Status;
> +}
> +
> +EFI_STATUS
> +AtSha204aRelease (
> + IN EFI_HANDLE DriverBindingHandle,
> + IN EFI_HANDLE ControllerHandle
> + )
> +{
> + EFI_RNG_PROTOCOL *Rng;
> + ATSHA204A_DEV *AtSha204a;
> + EFI_STATUS Status;
> +
> + Status = gBS->HandleProtocol (ControllerHandle,
> + &gEfiRngProtocolGuid,
> + (VOID **)&Rng);
> + ASSERT_EFI_ERROR (Status);
> + if (EFI_ERROR (Status)) {
> + return Status;
> + }
> +
> + AtSha204a = ATSHA204A_DEV_FROM_THIS (Rng);
> +
> + Status = gBS->UninstallProtocolInterface (ControllerHandle,
> + &gEfiRngProtocolGuid,
> + Rng);
> + ASSERT_EFI_ERROR (Status);
> + if (EFI_ERROR (Status)) {
> + return Status;
> + }
> +
> + Status = gBS->CloseProtocol (ControllerHandle,
> + &gEfiI2cIoProtocolGuid,
> + DriverBindingHandle,
> + ControllerHandle);
> + ASSERT_EFI_ERROR (Status);
> + if (EFI_ERROR (Status)) {
> + return Status;
> + }
> +
> + gBS->FreePool (AtSha204a);
> +
> + return EFI_SUCCESS;
> +}
> diff --git a/Silicon/Atmel/AtSha204a/AtSha204aDriver.h b/Silicon/Atmel/AtSha204a/AtSha204aDriver.h
> new file mode 100644
> index 000000000000..315a450d34f2
> --- /dev/null
> +++ b/Silicon/Atmel/AtSha204a/AtSha204aDriver.h
> @@ -0,0 +1,81 @@
> +/** @file
> + Device driver for the Atmel ATSHA204A random number generator.
> +
> + Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
> +
> + 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.
> +
> +**/
> +
> +#ifndef _ATSHA204A_I2C_HWRNG_DRIVER_H_
> +#define _ATSHA204A_I2C_HWRNG_DRIVER_H_
> +
> +#include <Uefi.h>
> +#include <Library/BaseMemoryLib.h>
> +#include <Library/DebugLib.h>
> +#include <Library/UefiBootServicesTableLib.h>
> +#include <Library/UefiLib.h>
> +
> +#include <Protocol/Rng.h>
> +#include <Protocol/I2cIo.h>
> +
> +#define ATSHA204A_OUTPUT_SIZE 32
> +
> +#define ATSHA204A_DEV_SIGNATURE SIGNATURE_32('a','t','s','h')
> +
> +typedef struct {
> + UINT32 Signature;
> + EFI_I2C_IO_PROTOCOL *I2cIo;
> + EFI_RNG_PROTOCOL Rng;
> +} ATSHA204A_DEV;
> +
> +#define ATSHA204A_DEV_FROM_THIS(a) \
> + CR(a, ATSHA204A_DEV, Rng, ATSHA204A_DEV_SIGNATURE)
> +
> +#pragma pack(1)
> +typedef struct {
> + UINT8 Command;
> + UINT8 Count;
> + UINT8 Opcode;
> + UINT8 Param1;
> + UINT16 Param2;
> + UINT16 Crc;
> +} ATSHA204A_I2C_RNG_COMMAND;
> +
> +typedef struct {
> + UINT8 Count;
> + UINT8 Result[ATSHA204A_OUTPUT_SIZE];
> + UINT16 Crc;
> +} ATSHA204A_I2C_RNG_RESULT;
> +#pragma pack()
> +
> +typedef struct {
> + UINTN OperationCount;
> + EFI_I2C_OPERATION Operation;
> +} I2C_RNG_REQUEST;
> +
> +#define ATSHA204A_COMMAND 0x3
> +
> +#define ATSHA204A_OPCODE_RANDOM 0x1b
> +
> +extern EFI_COMPONENT_NAME2_PROTOCOL gAtSha204aDriverComponentName2;
> +
> +EFI_STATUS
> +AtSha204aInit (
> + IN EFI_HANDLE DriverBindingHandle,
> + IN EFI_HANDLE ControllerHandle
> + );
> +
> +EFI_STATUS
> +AtSha204aRelease (
> + IN EFI_HANDLE DriverBindingHandle,
> + IN EFI_HANDLE ControllerHandle
> + );
> +
> +#endif // _ATSHA204A_I2C_HWRNG_DRIVER_H_
> diff --git a/Silicon/Atmel/AtSha204a/AtSha204aDxe.inf b/Silicon/Atmel/AtSha204a/AtSha204aDxe.inf
> new file mode 100644
> index 000000000000..fe90cc538114
> --- /dev/null
> +++ b/Silicon/Atmel/AtSha204a/AtSha204aDxe.inf
> @@ -0,0 +1,52 @@
> +## @file
> +# Device driver for the Atmel ATSHA204A random number generator.
> +#
> +# Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
> +#
> +# 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]
> + INF_VERSION = 0x0001001A
> + BASE_NAME = AtSha204aDxe
> + FILE_GUID = 8b8f683b-f376-4ba0-b8d7-b4bbd30319cc
> + MODULE_TYPE = UEFI_DRIVER
> + VERSION_STRING = 1.0
> + ENTRY_POINT = EntryPoint
> + UNLOAD_IMAGE = UnloadImage
> +
> +#
> +# VALID_ARCHITECTURES = AARCH64 ARM EBC IA32 IPF X64
> +#
> +
> +[Sources]
> + AtSha204aDriver.c
> + AtSha204aDriver.h
> + ComponentName.c
> + DriverBinding.c
> +
> +[Packages]
> + MdePkg/MdePkg.dec
> + Silicon/Atmel/AtSha204a/AtSha204a.dec
> +
> +[LibraryClasses]
> + BaseMemoryLib
> + DebugLib
> + UefiBootServicesTableLib
> + UefiDriverEntryPoint
> + UefiLib
> +
> +[Protocols]
> + gEfiRngProtocolGuid # PROTOCOL BY_START
> + gEfiI2cIoProtocolGuid # PROTOCOL TO_START
> +
> +[Guids]
> + gAtSha204aI2cDeviceGuid
> + gEfiRngAlgorithmRaw
> diff --git a/Silicon/Atmel/AtSha204a/ComponentName.c b/Silicon/Atmel/AtSha204a/ComponentName.c
> new file mode 100644
> index 000000000000..9893e7c4c2bf
> --- /dev/null
> +++ b/Silicon/Atmel/AtSha204a/ComponentName.c
> @@ -0,0 +1,186 @@
> +/** @file
> + UEFI Component Name(2) protocol implementation for AtSha204a driver.
> +
> + 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"
> +
> +STATIC EFI_UNICODE_STRING_TABLE mAtSha204aDriverNameTable[] = {
> + {
> + "en",
> + (CHAR16 *)L"AtSha204a RNG I2C driver"
> + },
> + { }
> +};
> +
> +STATIC EFI_UNICODE_STRING_TABLE mAtSha204aControllerNameTable[] = {
> + {
> + "en",
> + (CHAR16 *)L"AtSha204a Random Number Generator (I2C)"
> + },
> + { }
> +};
> +
> +/**
> + Retrieves a Unicode string that is the user readable name of the driver.
> +
> + This function retrieves the user readable name of a driver in the form of a
> + Unicode string. If the driver specified by This has a user readable name in
> + the language specified by Language, then a pointer to the driver name is
> + returned in DriverName, and EFI_SUCCESS is returned. If the driver specified
> + by This does not support the language specified by Language,
> + then EFI_UNSUPPORTED is returned.
> +
> + @param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
> + EFI_COMPONENT_NAME_PROTOCOL instance.
> +
> + @param Language[in] A pointer to a Null-terminated ASCII string
> + array indicating the language. This is the
> + language of the driver name that the caller is
> + requesting, and it must match one of the
> + languages specified in SupportedLanguages. The
> + number of languages supported by a driver is up
> + to the driver writer. Language is specified
> + in RFC 4646 or ISO 639-2 language code format.
> +
> + @param DriverName[out] A pointer to the Unicode string to return.
> + This Unicode string is the name of the
> + driver specified by This in the language
> + specified by Language.
> +
> + @retval EFI_SUCCESS The Unicode string for the Driver specified by
> + This and the language specified by Language was
> + returned in DriverName.
> +
> + @retval EFI_INVALID_PARAMETER Language is NULL.
> +
> + @retval EFI_INVALID_PARAMETER DriverName is NULL.
> +
> + @retval EFI_UNSUPPORTED The driver specified by This does not support
> + the language specified by Language.
> +
> +**/
> +STATIC
> +EFI_STATUS
> +EFIAPI
> +AtSha204aGetDriverName (
> + IN EFI_COMPONENT_NAME2_PROTOCOL *This,
> + IN CHAR8 *Language,
> + OUT CHAR16 **DriverName
> + )
> +{
> + return LookupUnicodeString2 (Language,
> + This->SupportedLanguages,
> + mAtSha204aDriverNameTable,
> + DriverName,
> + FALSE);
> +}
> +
> +/**
> + Retrieves a Unicode string that is the user readable name of the controller
> + that is being managed by a driver.
> +
> + This function retrieves the user readable name of the controller specified by
> + ControllerHandle and ChildHandle in the form of a Unicode string. If the
> + driver specified by This has a user readable name in the language specified by
> + Language, then a pointer to the controller name is returned in ControllerName,
> + and EFI_SUCCESS is returned. If the driver specified by This is not currently
> + managing the controller specified by ControllerHandle and ChildHandle,
> + then EFI_UNSUPPORTED is returned. If the driver specified by This does not
> + support the language specified by Language, then EFI_UNSUPPORTED is returned.
> +
> + @param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
> + EFI_COMPONENT_NAME_PROTOCOL instance.
> +
> + @param ControllerHandle[in] The handle of a controller that the driver
> + specified by This is managing. This handle
> + specifies the controller whose name is to be
> + returned.
> +
> + @param ChildHandle[in] The handle of the child controller to retrieve
> + the name of. This is an optional parameter that
> + may be NULL. It will be NULL for device
> + drivers. It will also be NULL for a bus drivers
> + that wish to retrieve the name of the bus
> + controller. It will not be NULL for a bus
> + driver that wishes to retrieve the name of a
> + child controller.
> +
> + @param Language[in] A pointer to a Null-terminated ASCII string
> + array indicating the language. This is the
> + language of the driver name that the caller is
> + requesting, and it must match one of the
> + languages specified in SupportedLanguages. The
> + number of languages supported by a driver is up
> + to the driver writer. Language is specified in
> + RFC 4646 or ISO 639-2 language code format.
> +
> + @param ControllerName[out] A pointer to the Unicode string to return.
> + This Unicode string is the name of the
> + controller specified by ControllerHandle and
> + ChildHandle in the language specified by
> + Language from the point of view of the driver
> + specified by This.
> +
> + @retval EFI_SUCCESS The Unicode string for the user readable name in
> + the language specified by Language for the
> + driver specified by This was returned in
> + DriverName.
> +
> + @retval EFI_INVALID_PARAMETER ControllerHandle is NULL.
> +
> + @retval EFI_INVALID_PARAMETER ChildHandle is not NULL and it is not a valid
> + EFI_HANDLE.
> +
> + @retval EFI_INVALID_PARAMETER Language is NULL.
> +
> + @retval EFI_INVALID_PARAMETER ControllerName is NULL.
> +
> + @retval EFI_UNSUPPORTED The driver specified by This is not currently
> + managing the controller specified by
> + ControllerHandle and ChildHandle.
> +
> + @retval EFI_UNSUPPORTED The driver specified by This does not support
> + the language specified by Language.
> +
> +**/
> +STATIC
> +EFI_STATUS
> +EFIAPI
> +AtSha204aGetControllerName (
> + IN EFI_COMPONENT_NAME2_PROTOCOL *This,
> + IN EFI_HANDLE ControllerHandle,
> + IN EFI_HANDLE ChildHandle OPTIONAL,
> + IN CHAR8 *Language,
> + OUT CHAR16 **ControllerName
> + )
> +{
> + if (ChildHandle != NULL) {
> + return EFI_UNSUPPORTED;
> + }
> +
> + return LookupUnicodeString2 (Language,
> + This->SupportedLanguages,
> + mAtSha204aControllerNameTable,
> + ControllerName,
> + FALSE);
> +}
> +
> +//
> +// EFI Component Name 2 Protocol
> +//
> +EFI_COMPONENT_NAME2_PROTOCOL gAtSha204aDriverComponentName2 = {
> + AtSha204aGetDriverName,
> + AtSha204aGetControllerName,
> + "en"
> +};
> diff --git a/Silicon/Atmel/AtSha204a/DriverBinding.c b/Silicon/Atmel/AtSha204a/DriverBinding.c
> new file mode 100644
> index 000000000000..17e61f96e8c5
> --- /dev/null
> +++ b/Silicon/Atmel/AtSha204a/DriverBinding.c
> @@ -0,0 +1,242 @@
> +/** @file
> + Device driver for the Atmel ATSHA204A random number generator.
> +
> + Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
> +
> + 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 <Library/UefiDriverEntryPoint.h>
> +
> +#include "AtSha204aDriver.h"
> +
> +/**
> + Tests to see if this driver supports a given controller.
> +
> + @param This[in] A pointer to the EFI_DRIVER_BINDING_PROTOCOL
> + instance.
> + @param ControllerHandle[in] The handle of the controller to test.
> + @param RemainingDevicePath[in] The remaining device path.
> + (Ignored - this is not a bus driver.)
> +
> + @retval EFI_SUCCESS The driver supports this controller.
> + @retval EFI_ALREADY_STARTED The device specified by ControllerHandle is
> + already being managed by the driver specified
> + by This.
> + @retval EFI_UNSUPPORTED The device specified by ControllerHandle is
> + not supported by the driver specified by This.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +I2cHwrngDriverBindingSupported (
> + IN EFI_DRIVER_BINDING_PROTOCOL *This,
> + IN EFI_HANDLE ControllerHandle,
> + IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
> + )
> +{
> + EFI_I2C_IO_PROTOCOL *I2cIo;
> + EFI_STATUS Status;
> +
> + //
> + // Connect to the I2C stack
> + //
> + Status = gBS->OpenProtocol (ControllerHandle,
> + &gEfiI2cIoProtocolGuid,
> + (VOID **) &I2cIo,
> + This->DriverBindingHandle,
> + ControllerHandle,
> + EFI_OPEN_PROTOCOL_BY_DRIVER);
> + if (EFI_ERROR (Status)) {
> + return Status;
> + }
> +
> + if (CompareGuid (I2cIo->DeviceGuid, &gAtSha204aI2cDeviceGuid)) {
> + DEBUG ((DEBUG_INIT | DEBUG_INFO, "Detected AtSha204a RNG device\n"));
> + Status = EFI_SUCCESS;
> + } else {
> + Status = EFI_UNSUPPORTED;
> + }
> +
> + //
> + // Clean up.
> + //
> + gBS->CloseProtocol (ControllerHandle,
> + &gEfiI2cIoProtocolGuid,
> + This->DriverBindingHandle,
> + ControllerHandle);
> +
> + return Status;
> +}
> +
> +
> +/**
> + Starts a device controller or a bus controller.
> +
> + @param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL
> + instance.
> + @param[in] ControllerHandle The handle of the device to start. This
> + handle must support a protocol interface that
> + supplies an I/O abstraction to the driver.
> + @param[in] RemainingDevicePath The remaining portion of the device path.
> + (Ignored - this is not a bus driver.)
> +
> + @retval EFI_SUCCESS The device was started.
> + @retval EFI_DEVICE_ERROR The device could not be started due to a
> + device error.
> + @retval EFI_OUT_OF_RESOURCES The request could not be completed due to a
> + lack of resources.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +I2cHwrngDriverBindingStart (
> + IN EFI_DRIVER_BINDING_PROTOCOL *This,
> + IN EFI_HANDLE ControllerHandle,
> + IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL
> + )
> +{
> + return AtSha204aInit (This->DriverBindingHandle, ControllerHandle);
> +}
> +
> +
> +/**
> + Stops a device controller or a bus controller.
> +
> + @param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL
> + instance.
> + @param[in] ControllerHandle A handle to the device being stopped. The handle
> + must support a bus specific I/O protocol for the
> + driver to use to stop the device.
> + @param[in] NumberOfChildren The number of child device handles in
> + ChildHandleBuffer.
> + @param[in] ChildHandleBuffer An array of child handles to be freed. May be
> + NULL if NumberOfChildren is 0.
> +
> + @retval EFI_SUCCESS The device was stopped.
> + @retval EFI_DEVICE_ERROR The device could not be stopped due to a device
> + error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +I2cHwrngDriverBindingStop (
> + IN EFI_DRIVER_BINDING_PROTOCOL *This,
> + IN EFI_HANDLE ControllerHandle,
> + IN UINTN NumberOfChildren,
> + IN EFI_HANDLE *ChildHandleBuffer OPTIONAL
> + )
> +{
> + return AtSha204aRelease (This->DriverBindingHandle, ControllerHandle);
> +}
> +
> +
> +STATIC
> +EFI_DRIVER_BINDING_PROTOCOL gI2cHwrngDriverBinding = {
> + I2cHwrngDriverBindingSupported,
> + I2cHwrngDriverBindingStart,
> + I2cHwrngDriverBindingStop,
> + 0xa,
> + NULL,
> + NULL
> +};
> +
> +
> +/**
> + The entry point of AtSha204a UEFI Driver.
> +
> + @param ImageHandle The image handle of the UEFI Driver.
> + @param SystemTable A pointer to the EFI System Table.
> +
> + @retval EFI_SUCCESS The Driver or UEFI Driver exited normally.
> + @retval EFI_INCOMPATIBLE_VERSION _gUefiDriverRevision is greater than
> + SystemTable->Hdr.Revision.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +EntryPoint (
> + IN EFI_HANDLE ImageHandle,
> + IN EFI_SYSTEM_TABLE *SystemTable
> + )
> +{
> + EFI_STATUS Status;
> +
> + //
> + // Add the driver to the list of drivers
> + //
> + Status = EfiLibInstallDriverBindingComponentName2 (
> + ImageHandle, SystemTable, &gI2cHwrngDriverBinding, ImageHandle,
> + NULL, &gAtSha204aDriverComponentName2);
> + ASSERT_EFI_ERROR (Status);
> +
> + DEBUG ((DEBUG_INIT | DEBUG_INFO, "*** Installed AtSha204a driver! ***\n"));
> +
> + return EFI_SUCCESS;
> +}
> +
> +
> +/**
> + Unload function for the AtSha204a Driver.
> +
> + @param ImageHandle[in] The allocated handle for the EFI image
> +
> + @retval EFI_SUCCESS The driver was unloaded successfully
> + @retval EFI_INVALID_PARAMETER ImageHandle is not a valid image handle.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +UnloadImage (
> + IN EFI_HANDLE ImageHandle
> + )
> +{
> + EFI_STATUS Status;
> + EFI_HANDLE *HandleBuffer;
> + UINTN HandleCount;
> + UINTN Index;
> +
> + //
> + // Retrieve all I2C I/O handles in the handle database
> + //
> + Status = gBS->LocateHandleBuffer (ByProtocol,
> + &gEfiI2cIoProtocolGuid,
> + NULL,
> + &HandleCount,
> + &HandleBuffer);
> + if (EFI_ERROR (Status)) {
> + return Status;
> + }
> +
> + //
> + // Disconnect the driver from the handles in the handle database
> + //
> + for (Index = 0; Index < HandleCount; Index++) {
> + Status = gBS->DisconnectController (HandleBuffer[Index],
> + gImageHandle,
> + NULL);
> + }
> +
> + //
> + // Free the handle array
> + //
> + gBS->FreePool (HandleBuffer);
> +
> + //
> + // Uninstall protocols installed by the driver in its entrypoint
> + //
> + Status = gBS->UninstallMultipleProtocolInterfaces (ImageHandle,
> + &gEfiDriverBindingProtocolGuid,
> + &gI2cHwrngDriverBinding,
> + NULL
> + );
> +
> + return EFI_SUCCESS;
> +}
> --
> 2.11.0
>
next prev parent reply other threads:[~2018-02-19 17:22 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-19 9:43 [PATCH] Silicon/Atmel: add support for AtSha204a RNG Ard Biesheuvel
2018-02-19 17:28 ` Leif Lindholm [this message]
2018-02-19 18:19 ` Ard Biesheuvel
2018-02-19 20:07 ` Leif Lindholm
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