From c326fe96050cf80992ded7726e9222ac5305a908 Mon Sep 17 00:00:00 2001
From: Dean Camera <dean@fourwalledcubicle.com>
Date: Fri, 9 Jul 2010 07:24:34 +0000
Subject: [PATCH] Rewrote the implementation of the SwapEndian_16() and
SwapEndian_32() functions so that they compile down in most instances to
minimal loads and stores rather than complicated shifts.
Fixed SCSI.c implementations of all the demos/projects casting the block count to a 32-bit temporary before calling SwapEndian_16().
---
.../Device/ClassDriver/MassStorage/Lib/SCSI.c | 4 +-
.../MassStorageKeyboard/Lib/SCSI.c | 18 ++++-----
Demos/Device/LowLevel/MassStorage/Lib/SCSI.c | 20 ++++------
LUFA/Common/Common.h | 39 ++++++++++++++++---
LUFA/ManPages/ChangeLog.txt | 2 +
.../StandaloneProgrammer/Lib/SCSI.c | 6 +--
Projects/TemperatureDataLogger/Lib/SCSI.c | 6 +--
Projects/Webserver/Lib/SCSI.c | 6 +--
8 files changed, 62 insertions(+), 39 deletions(-)
diff --git a/Demos/Device/ClassDriver/MassStorage/Lib/SCSI.c b/Demos/Device/ClassDriver/MassStorage/Lib/SCSI.c
index 6c20576c8..08b055fbe 100644
--- a/Demos/Device/ClassDriver/MassStorage/Lib/SCSI.c
+++ b/Demos/Device/ClassDriver/MassStorage/Lib/SCSI.c
@@ -160,7 +160,7 @@ static void SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -257,7 +257,7 @@ static void SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* MSInterfaceInfo
BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
/* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
- TotalBlocks = SwapEndian_16(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
+ TotalBlocks = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= LUN_MEDIA_BLOCKS)
diff --git a/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c b/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c
index 2b4477aad..897090c91 100644
--- a/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c
+++ b/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c
@@ -170,7 +170,7 @@ static bool SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -196,7 +196,7 @@ static bool SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* MSInterfaceInf
uint8_t PadBytes[AllocationLength - BytesTransferred];
Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NO_STREAM_CALLBACK);
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
Endpoint_ClearIN();
/* Succeed the command and update the bytes transferred counter */
@@ -306,15 +306,11 @@ static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* MSInterfaceInfo
uint32_t BlockAddress;
uint16_t TotalBlocks;
- /* Load in the 32-bit block address (SCSI uses big-endian, so have to do it byte-by-byte) */
- ((uint8_t*)&BlockAddress)[3] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[2];
- ((uint8_t*)&BlockAddress)[2] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[3];
- ((uint8_t*)&BlockAddress)[1] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[4];
- ((uint8_t*)&BlockAddress)[0] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[5];
-
- /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to do it byte-by-byte) */
- ((uint8_t*)&TotalBlocks)[1] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[7];
- ((uint8_t*)&TotalBlocks)[0] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[8];
+ /* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
+ BlockAddress = SwapEndian_32(*(uint32_t*)&CommandBlock.SCSICommandData[2]);
+
+ /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
+ TotalBlocks = SwapEndian_16(*(uint16_t*)&CommandBlock.SCSICommandData[7]);
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= LUN_MEDIA_BLOCKS)
diff --git a/Demos/Device/LowLevel/MassStorage/Lib/SCSI.c b/Demos/Device/LowLevel/MassStorage/Lib/SCSI.c
index 10e6bc4a7..111c3b726 100644
--- a/Demos/Device/LowLevel/MassStorage/Lib/SCSI.c
+++ b/Demos/Device/LowLevel/MassStorage/Lib/SCSI.c
@@ -159,7 +159,7 @@ static void SCSI_Command_Inquiry(void)
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), StreamCallback_AbortOnMassStoreReset);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), StreamCallback_AbortOnMassStoreReset);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -182,7 +182,7 @@ static void SCSI_Command_Request_Sense(void)
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), StreamCallback_AbortOnMassStoreReset);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), StreamCallback_AbortOnMassStoreReset);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -256,16 +256,12 @@ static void SCSI_Command_ReadWrite_10(const bool IsDataRead)
uint32_t BlockAddress;
uint16_t TotalBlocks;
- /* Load in the 32-bit block address (SCSI uses big-endian, so have to do it byte-by-byte) */
- ((uint8_t*)&BlockAddress)[3] = CommandBlock.SCSICommandData[2];
- ((uint8_t*)&BlockAddress)[2] = CommandBlock.SCSICommandData[3];
- ((uint8_t*)&BlockAddress)[1] = CommandBlock.SCSICommandData[4];
- ((uint8_t*)&BlockAddress)[0] = CommandBlock.SCSICommandData[5];
-
- /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to do it byte-by-byte) */
- ((uint8_t*)&TotalBlocks)[1] = CommandBlock.SCSICommandData[7];
- ((uint8_t*)&TotalBlocks)[0] = CommandBlock.SCSICommandData[8];
-
+ /* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
+ BlockAddress = SwapEndian_32(*(uint32_t*)&CommandBlock.SCSICommandData[2]);
+
+ /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
+ TotalBlocks = SwapEndian_16(*(uint16_t*)&CommandBlock.SCSICommandData[7]);
+
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= LUN_MEDIA_BLOCKS)
{
diff --git a/LUFA/Common/Common.h b/LUFA/Common/Common.h
index 7fd15554c..76144f94b 100644
--- a/LUFA/Common/Common.h
+++ b/LUFA/Common/Common.h
@@ -174,7 +174,21 @@
static inline uint16_t SwapEndian_16(uint16_t Word) ATTR_WARN_UNUSED_RESULT ATTR_CONST;
static inline uint16_t SwapEndian_16(uint16_t Word)
{
- return ((Word >> 8) | (Word << 8));
+ uint8_t Temp;
+
+ union
+ {
+ uint16_t Word;
+ uint8_t Bytes[2];
+ } Data;
+
+ Data.Word = Word;
+
+ Temp = Data.Bytes[0];
+ Data.Bytes[0] = Data.Bytes[1];
+ Data.Bytes[1] = Temp;
+
+ return Data.Word;
}
/** Function to reverse the byte ordering of the individual bytes in a 32 bit number.
@@ -186,10 +200,25 @@
static inline uint32_t SwapEndian_32(uint32_t DWord) ATTR_WARN_UNUSED_RESULT ATTR_CONST;
static inline uint32_t SwapEndian_32(uint32_t DWord)
{
- return (((DWord & 0xFF000000) >> 24) |
- ((DWord & 0x00FF0000) >> 8) |
- ((DWord & 0x0000FF00) << 8) |
- ((DWord & 0x000000FF) << 24));
+ uint8_t Temp;
+
+ union
+ {
+ uint32_t DWord;
+ uint8_t Bytes[4];
+ } Data;
+
+ Data.DWord = DWord;
+
+ Temp = Data.Bytes[0];
+ Data.Bytes[0] = Data.Bytes[3];
+ Data.Bytes[3] = Temp;
+
+ Temp = Data.Bytes[1];
+ Data.Bytes[1] = Data.Bytes[2];
+ Data.Bytes[2] = Temp;
+
+ return Data.DWord;
}
/** Function to reverse the byte ordering of the individual bytes in a n byte number.
diff --git a/LUFA/ManPages/ChangeLog.txt b/LUFA/ManPages/ChangeLog.txt
index 593751af1..0a2f43a33 100644
--- a/LUFA/ManPages/ChangeLog.txt
+++ b/LUFA/ManPages/ChangeLog.txt
@@ -25,6 +25,8 @@
* - Removed unused line encoding data and control requests from the CDC Bootloader code, to save space
* - Renamed SERIAL_STREAM_ASSERT() macro to STDOUT_ASSERT()
* - The USB_Device_IsRemoteWakeupSent() and USB_Device_IsUSBSuspended() macros have been deleted, as they are now obsolete
+ * - Rewrote the implementation of the SwapEndian_16() and SwapEndian_32() functions so that they compile down in most instances to
+ * minimal loads and stores rather than complicated shifts
*
* <b>Fixed:</b>
* - Fixed AVRISP project sending a LOAD EXTENDED ADDRESS command to 128KB AVRs after programming or reading from
diff --git a/Projects/Incomplete/StandaloneProgrammer/Lib/SCSI.c b/Projects/Incomplete/StandaloneProgrammer/Lib/SCSI.c
index 402160496..21dfbfa8f 100644
--- a/Projects/Incomplete/StandaloneProgrammer/Lib/SCSI.c
+++ b/Projects/Incomplete/StandaloneProgrammer/Lib/SCSI.c
@@ -161,7 +161,7 @@ static void SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* const MSInterfaceInf
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -183,7 +183,7 @@ static void SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* const MSInterf
uint8_t PadBytes[AllocationLength - BytesTransferred];
Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NO_STREAM_CALLBACK);
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
Endpoint_ClearIN();
/* Succeed the command and update the bytes transferred counter */
@@ -258,7 +258,7 @@ static void SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfa
BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
/* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
- TotalBlocks = SwapEndian_16(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
+ TotalBlocks = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= VIRTUAL_MEMORY_BLOCKS)
diff --git a/Projects/TemperatureDataLogger/Lib/SCSI.c b/Projects/TemperatureDataLogger/Lib/SCSI.c
index 55312e87b..d499d9ac3 100644
--- a/Projects/TemperatureDataLogger/Lib/SCSI.c
+++ b/Projects/TemperatureDataLogger/Lib/SCSI.c
@@ -160,7 +160,7 @@ static void SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* const MSInterfaceInf
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -182,7 +182,7 @@ static void SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* const MSInterf
uint8_t PadBytes[AllocationLength - BytesTransferred];
Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NO_STREAM_CALLBACK);
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
Endpoint_ClearIN();
/* Succeed the command and update the bytes transferred counter */
@@ -257,7 +257,7 @@ static void SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfa
BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
/* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
- TotalBlocks = SwapEndian_16(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
+ TotalBlocks = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= VIRTUAL_MEMORY_BLOCKS)
diff --git a/Projects/Webserver/Lib/SCSI.c b/Projects/Webserver/Lib/SCSI.c
index 55312e87b..d499d9ac3 100644
--- a/Projects/Webserver/Lib/SCSI.c
+++ b/Projects/Webserver/Lib/SCSI.c
@@ -160,7 +160,7 @@ static void SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* const MSInterfaceInf
uint8_t PadBytes[AllocationLength - BytesTransferred];
/* Pad out remaining bytes with 0x00 */
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
@@ -182,7 +182,7 @@ static void SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* const MSInterf
uint8_t PadBytes[AllocationLength - BytesTransferred];
Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NO_STREAM_CALLBACK);
- Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
+ Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
Endpoint_ClearIN();
/* Succeed the command and update the bytes transferred counter */
@@ -257,7 +257,7 @@ static void SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfa
BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
/* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
- TotalBlocks = SwapEndian_16(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
+ TotalBlocks = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= VIRTUAL_MEMORY_BLOCKS)
--
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