[PATCH v3 0/8] staging: r8188eu: fix and clean up some firmware code

[PATCH v3 0/8] staging: r8188eu: fix and clean up some firmware code

[Michael Straube]

This series fixes wrong size of struct rt_firmware_hdr in the first
patch and does some cleanups in rtl8188e_firmware_download() in the
other patches.

Tested on x86_64 with Inter-Tech DMG-02.

v3:
- Splitted the first patch into two separate patches.
- Added back logging the firmware version only once.
- Included the compile time check for size of rt_firmware from
  patch 8/8 of v2 in the patch that replaces the hardcoded size.

v2:
- Added a patch to check size of struct rt_firmware_hdr at compile time.

Michael Straube (8):
  staging: r8188eu: fix struct rt_firmware_hdr
  staging: r8188eu: convert u32 fields of rt_firmware_hdr to __le32
  staging: r8188eu: clean up comments in struct rt_firmware_hdr
  staging: r8188eu: rename fields of struct rt_firmware_hdr
  staging: r8188eu: use sizeof instead of hardcoded firmware header size
  staging: r8188eu: remove variables from rtl8188e_firmware_download()
  staging: r8188eu: use pr_info_once() to log the firmware version
  staging: r8188eu: check firmware header existence before access

 drivers/staging/r8188eu/core/rtw_fw.c | 79 ++++++++++-----------------
 1 file changed, 29 insertions(+), 50 deletions(-)

-- 
2.35.1

[PATCH v3 1/8] staging: r8188eu: fix struct rt_firmware_hdr

[Michael Straube]

The size of struct rt_firmware_hdr is 36 bytes.

$ pahole -C rt_firmware_hdr drivers/staging/r8188eu/r8188eu.o
struct rt_firmware_hdr {
        __le16                     Signature;            /*     0     2 */
        u8                         Category;             /*     2     1 */
        u8                         Function;             /*     3     1 */
        __le16                     Version;              /*     4     2 */
        u8                         Subversion;           /*     6     1 */

        /* XXX 1 byte hole, try to pack */

        u16                        Rsvd1;                /*     8     2 */
        u8                         Month;                /*    10     1 */
        u8                         Date;                 /*    11     1 */
        u8                         Hour;                 /*    12     1 */
        u8                         Minute;               /*    13     1 */
        __le16                     RamCodeSize;          /*    14     2 */
        u8                         Foundry;              /*    16     1 */
        u8                         Rsvd2;                /*    17     1 */

        /* XXX 2 bytes hole, try to pack */

        __le32                     SvnIdx;               /*    20     4 */
        u32                        Rsvd3;                /*    24     4 */
        u32                        Rsvd4;                /*    28     4 */
        u32                        Rsvd5;                /*    32     4 */

        /* size: 36, cachelines: 1, members: 17 */
        /* sum members: 33, holes: 2, sum holes: 3 */
        /* last cacheline: 36 bytes */
};

But the header in the firmware file is only 32 bytes long.

The hexdump of rtl8188eufw.bin shows that the field Rsvd1 should be u8
instead of __le16.

OFFSET      rtl8188eufw.bin
-----------------------------------------------------------
0x00000000  E1 88 10 00 0B 00 01 00 01 21 11 27 30 36 00 00
0x00000010  2D 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00

0x00000000  E1 88 10 00 0B 00 01  00     01     21    11    27 30 36 00 00
                              ^   ^      ^      ^     ^     ^
                     Subversion   Rsvd1  Month  Date  Hour  Minute

With the change of field Rsvd1 from __le16 to u8 the structure has the
correct size 32.

$ pahole -C rt_firmware_hdr drivers/staging/r8188eu/r8188eu.o
struct rt_firmware_hdr {
        __le16                     Signature;            /*     0     2 */
        u8                         Category;             /*     2     1 */
        u8                         Function;             /*     3     1 */
        __le16                     Version;              /*     4     2 */
        u8                         Subversion;           /*     6     1 */
        u8                         Rsvd1;                /*     7     1 */
        u8                         Month;                /*     8     1 */
        u8                         Date;                 /*     9     1 */
        u8                         Hour;                 /*    10     1 */
        u8                         Minute;               /*    11     1 */
        __le16                     RamCodeSize;          /*    12     2 */
        u8                         Foundry;              /*    14     1 */
        u8                         Rsvd2;                /*    15     1 */
        __le32                     SvnIdx;               /*    16     4 */
        u32                        Rsvd3;                /*    20     4 */
        u32                        Rsvd4;                /*    24     4 */
        u32                        Rsvd5;                /*    28     4 */

        /* size: 32, cachelines: 1, members: 17 */
        /* last cacheline: 32 bytes */

The wrong size had no effect because the header size is hardcoded to
32 where it is used in the code and the fields after Subversion are
not used.

Fixes: 7884fc0a1473 ("staging: r8188eu: introduce new include dir for RTL8188eu driver")
Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- updated the commit message
- moved the u32 to __le32 conversions to a separate patch

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index 8620f3c92b52..eb4ab11f6b28 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -29,7 +29,7 @@ struct rt_firmware_hdr {
 					 *  FW for different conditions */
 	__le16		Version;	/*  FW Version */
 	u8		Subversion;	/*  FW Subversion, default 0x00 */
-	u16		Rsvd1;
+	u8		Rsvd1;
 
 	/*  LONG WORD 1 ---- */
 	u8		Month;	/*  Release time Month field */
-- 
2.35.1

[PATCH v3 2/8] staging: r8188eu: convert u32 fields of rt_firmware_hdr to __le32

[Michael Straube]

Convert the u32 fields of struct rt_firmware_hdr to __le32 for
consistency.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- this patch was part of patch 1/8 in v2

 drivers/staging/r8188eu/core/rtw_fw.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index eb4ab11f6b28..7cd08268f3b9 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -42,11 +42,11 @@ struct rt_firmware_hdr {
 
 	/*  LONG WORD 2 ---- */
 	__le32		SvnIdx;	/*  The SVN entry index */
-	u32		Rsvd3;
+	__le32		Rsvd3;
 
 	/*  LONG WORD 3 ---- */
-	u32		Rsvd4;
-	u32		Rsvd5;
+	__le32		Rsvd4;
+	__le32		Rsvd5;
 };
 
 static void fw_download_enable(struct adapter *padapter, bool enable)
-- 
2.35.1

[PATCH v3 3/8] staging: r8188eu: clean up comments in struct rt_firmware_hdr

[Michael Straube]

The comments in struct rt_firmware_hdr are not needed.
Remove them.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- no changes

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 37 ++++++++-------------------
 1 file changed, 11 insertions(+), 26 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index 7cd08268f3b9..323e0c634c4e 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -14,37 +14,22 @@
 	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x2300 ||	\
 	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x88E0)
 
-/*  This structure must be careful with byte-ordering */
-
 struct rt_firmware_hdr {
-	/*  8-byte alinment required */
-	/*  LONG WORD 0 ---- */
-	__le16		Signature;	/* 92C0: test chip; 92C,
-					 * 88C0: test chip; 88C1: MP A-cut;
-					 * 92C1: MP A-cut */
-	u8		Category;	/*  AP/NIC and USB/PCI */
-	u8		Function;	/*  Reserved for different FW function
-					 *  indcation, for further use when
-					 *  driver needs to download different
-					 *  FW for different conditions */
-	__le16		Version;	/*  FW Version */
-	u8		Subversion;	/*  FW Subversion, default 0x00 */
+	__le16		Signature;
+	u8		Category;
+	u8		Function;
+	__le16		Version;
+	u8		Subversion;
 	u8		Rsvd1;
-
-	/*  LONG WORD 1 ---- */
-	u8		Month;	/*  Release time Month field */
-	u8		Date;	/*  Release time Date field */
-	u8		Hour;	/*  Release time Hour field */
-	u8		Minute;	/*  Release time Minute field */
-	__le16		RamCodeSize;	/*  The size of RAM code */
+	u8		Month;
+	u8		Date;
+	u8		Hour;
+	u8		Minute;
+	__le16		RamCodeSize;
 	u8		Foundry;
 	u8		Rsvd2;
-
-	/*  LONG WORD 2 ---- */
-	__le32		SvnIdx;	/*  The SVN entry index */
+	__le32		SvnIdx;
 	__le32		Rsvd3;
-
-	/*  LONG WORD 3 ---- */
 	__le32		Rsvd4;
 	__le32		Rsvd5;
 };
-- 
2.35.1

[PATCH v3 4/8] staging: r8188eu: rename fields of struct rt_firmware_hdr

[Michael Straube]

Rename the fields of struct rt_firmware_hdr to avoid camel case.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- no changes

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 48 +++++++++++++--------------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index 323e0c634c4e..3da52a1ba23c 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -9,29 +9,29 @@
 #define MAX_PAGE_SIZE		4096
 
 #define IS_FW_HEADER_EXIST(_fwhdr)				\
-	((le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x92C0 ||	\
-	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x88C0 ||	\
-	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x2300 ||	\
-	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x88E0)
+	((le16_to_cpu(_fwhdr->signature) & 0xFFF0) == 0x92C0 ||	\
+	(le16_to_cpu(_fwhdr->signature) & 0xFFF0) == 0x88C0 ||	\
+	(le16_to_cpu(_fwhdr->signature) & 0xFFF0) == 0x2300 ||	\
+	(le16_to_cpu(_fwhdr->signature) & 0xFFF0) == 0x88E0)
 
 struct rt_firmware_hdr {
-	__le16		Signature;
-	u8		Category;
-	u8		Function;
-	__le16		Version;
-	u8		Subversion;
-	u8		Rsvd1;
-	u8		Month;
-	u8		Date;
-	u8		Hour;
-	u8		Minute;
-	__le16		RamCodeSize;
-	u8		Foundry;
-	u8		Rsvd2;
-	__le32		SvnIdx;
-	__le32		Rsvd3;
-	__le32		Rsvd4;
-	__le32		Rsvd5;
+	__le16	signature;
+	u8	category;
+	u8	function;
+	__le16	version;
+	u8	subversion;
+	u8	rsvd1;
+	u8	month;
+	u8	date;
+	u8	hour;
+	u8	minute;
+	__le16	ramcodesize;
+	u8	foundry;
+	u8	rsvd2;
+	__le32	svnidx;
+	__le32	rsvd3;
+	__le32	rsvd4;
+	__le32	rsvd5;
 };
 
 static void fw_download_enable(struct adapter *padapter, bool enable)
@@ -254,9 +254,9 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	/*  To Check Fw header. Added by tynli. 2009.12.04. */
 	fwhdr = (struct rt_firmware_hdr *)dvobj->firmware.data;
 
-	fw_version = le16_to_cpu(fwhdr->Version);
-	fw_subversion = fwhdr->Subversion;
-	fw_signature = le16_to_cpu(fwhdr->Signature);
+	fw_version = le16_to_cpu(fwhdr->version);
+	fw_subversion = fwhdr->subversion;
+	fw_signature = le16_to_cpu(fwhdr->signature);
 
 	if (!log_version++)
 		pr_info("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
-- 
2.35.1

[PATCH v3 5/8] staging: r8188eu: use sizeof instead of hardcoded firmware header size

[Michael Straube]

Use sizeof() instead of hardcoding the firmware header size and add
a compile time check to ensure struct rt_firmware_hdr has the correct
size.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- added the compile time size check from patch 8/8 of v2

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index 3da52a1ba23c..0279af37719a 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -34,6 +34,8 @@ struct rt_firmware_hdr {
 	__le32	rsvd5;
 };
 
+static_assert(sizeof(struct rt_firmware_hdr) == 32);
+
 static void fw_download_enable(struct adapter *padapter, bool enable)
 {
 	u8 tmp;
@@ -263,9 +265,8 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 			DRIVER_PREFIX, fw_version, fw_subversion, fw_signature);
 
 	if (IS_FW_HEADER_EXIST(fwhdr)) {
-		/*  Shift 32 bytes for FW header */
-		fw_data = fw_data + 32;
-		fw_size = fw_size - 32;
+		fw_data = fw_data + sizeof(struct rt_firmware_hdr);
+		fw_size = fw_size - sizeof(struct rt_firmware_hdr);
 	}
 
 	/*  Suggested by Filen. If 8051 is running in RAM code, driver should inform Fw to reset by itself, */
-- 
2.35.1

[PATCH v3 6/8] staging: r8188eu: remove variables from rtl8188e_firmware_download()

[Michael Straube]

The local variables fw_version, fw_subversion, fw_signature in
rtl8188e_firmware_download() are only used in one place. Use the
assigned values directly and remove the variables to make the code
shorter and cleaner.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- no changes

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index 0279af37719a..c102aba099f5 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -239,7 +239,6 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	struct dvobj_priv *dvobj = adapter_to_dvobj(padapter);
 	struct device *device = dvobj_to_dev(dvobj);
 	struct rt_firmware_hdr *fwhdr = NULL;
-	u16 fw_version, fw_subversion, fw_signature;
 	u8 *fw_data;
 	u32 fw_size;
 	static int log_version;
@@ -256,13 +255,10 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	/*  To Check Fw header. Added by tynli. 2009.12.04. */
 	fwhdr = (struct rt_firmware_hdr *)dvobj->firmware.data;
 
-	fw_version = le16_to_cpu(fwhdr->version);
-	fw_subversion = fwhdr->subversion;
-	fw_signature = le16_to_cpu(fwhdr->signature);
-
 	if (!log_version++)
 		pr_info("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
-			DRIVER_PREFIX, fw_version, fw_subversion, fw_signature);
+			DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
+			le16_to_cpu(fwhdr->signature));
 
 	if (IS_FW_HEADER_EXIST(fwhdr)) {
 		fw_data = fw_data + sizeof(struct rt_firmware_hdr);
-- 
2.35.1

[PATCH v3 7/8] staging: r8188eu: use pr_info_once() to log the firmware version

[Michael Straube]

Use pr_info_once() instead of a static variable and an if statement
to log the firmware version only once.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- added back logging the firmware version only once, using
  pr_info_once() instead of a static variable and if statement

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index c102aba099f5..7ee72236c7f4 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -241,7 +241,6 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	struct rt_firmware_hdr *fwhdr = NULL;
 	u8 *fw_data;
 	u32 fw_size;
-	static int log_version;
 
 	if (!dvobj->firmware.data)
 		ret = load_firmware(&dvobj->firmware, device);
@@ -255,10 +254,9 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	/*  To Check Fw header. Added by tynli. 2009.12.04. */
 	fwhdr = (struct rt_firmware_hdr *)dvobj->firmware.data;
 
-	if (!log_version++)
-		pr_info("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
-			DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
-			le16_to_cpu(fwhdr->signature));
+	pr_info_once("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
+		     DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
+		     le16_to_cpu(fwhdr->signature));
 
 	if (IS_FW_HEADER_EXIST(fwhdr)) {
 		fw_data = fw_data + sizeof(struct rt_firmware_hdr);
-- 
2.35.1

[PATCH v3 8/8] staging: r8188eu: check firmware header existence before access

[Michael Straube]

We should access the fields of fwhdr only if the check for firmware
header existence is true. Move the affected code into the if block
that checks firmware header existence.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
---
v3:
- no real changes,
  just the pr_info() -> pr_info_once() from patch 7/8 is different

v2:
- no changes

 drivers/staging/r8188eu/core/rtw_fw.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
index 7ee72236c7f4..8b5c67780a7b 100644
--- a/drivers/staging/r8188eu/core/rtw_fw.c
+++ b/drivers/staging/r8188eu/core/rtw_fw.c
@@ -251,14 +251,13 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	fw_data = dvobj->firmware.data;
 	fw_size = dvobj->firmware.size;
 
-	/*  To Check Fw header. Added by tynli. 2009.12.04. */
 	fwhdr = (struct rt_firmware_hdr *)dvobj->firmware.data;
 
-	pr_info_once("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
-		     DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
-		     le16_to_cpu(fwhdr->signature));
-
 	if (IS_FW_HEADER_EXIST(fwhdr)) {
+		pr_info_once("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
+			     DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
+			     le16_to_cpu(fwhdr->signature));
+
 		fw_data = fw_data + sizeof(struct rt_firmware_hdr);
 		fw_size = fw_size - sizeof(struct rt_firmware_hdr);
 	}
-- 
2.35.1

Re: [PATCH v3 3/8] staging: r8188eu: clean up comments in struct rt_firmware_hdr

[Larry Finger]

On 4/15/22 07:10, Michael Straube wrote:
> The comments in struct rt_firmware_hdr are not needed.
> Remove them.
> 
> Signed-off-by: Michael Straube <straube.linux@gmail.com>
> ---
> v3:
> - no changes
> 
> v2:
> - no changes
> 
>   drivers/staging/r8188eu/core/rtw_fw.c | 37 ++++++++-------------------
>   1 file changed, 11 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/staging/r8188eu/core/rtw_fw.c b/drivers/staging/r8188eu/core/rtw_fw.c
> index 7cd08268f3b9..323e0c634c4e 100644
> --- a/drivers/staging/r8188eu/core/rtw_fw.c
> +++ b/drivers/staging/r8188eu/core/rtw_fw.c
> @@ -14,37 +14,22 @@
>   	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x2300 ||	\
>   	(le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x88E0)
>   
> -/*  This structure must be careful with byte-ordering */
> -
>   struct rt_firmware_hdr {
> -	/*  8-byte alinment required */
> -	/*  LONG WORD 0 ---- */
> -	__le16		Signature;	/* 92C0: test chip; 92C,
> -					 * 88C0: test chip; 88C1: MP A-cut;
> -					 * 92C1: MP A-cut */
> -	u8		Category;	/*  AP/NIC and USB/PCI */
> -	u8		Function;	/*  Reserved for different FW function
> -					 *  indcation, for further use when
> -					 *  driver needs to download different
> -					 *  FW for different conditions */
> -	__le16		Version;	/*  FW Version */
> -	u8		Subversion;	/*  FW Subversion, default 0x00 */
> +	__le16		Signature;
> +	u8		Category;
> +	u8		Function;
> +	__le16		Version;
> +	u8		Subversion;
>   	u8		Rsvd1;
> -
> -	/*  LONG WORD 1 ---- */
> -	u8		Month;	/*  Release time Month field */
> -	u8		Date;	/*  Release time Date field */
> -	u8		Hour;	/*  Release time Hour field */
> -	u8		Minute;	/*  Release time Minute field */
> -	__le16		RamCodeSize;	/*  The size of RAM code */
> +	u8		Month;
> +	u8		Date;
> +	u8		Hour;
> +	u8		Minute;
> +	__le16		RamCodeSize;
>   	u8		Foundry;
>   	u8		Rsvd2;
> -
> -	/*  LONG WORD 2 ---- */
> -	__le32		SvnIdx;	/*  The SVN entry index */
> +	__le32		SvnIdx;
>   	__le32		Rsvd3;
> -
> -	/*  LONG WORD 3 ---- */
>   	__le32		Rsvd4;
>   	__le32		Rsvd5;
>   };

The comments "LONG WORD" are useless, but the comments describing the fields are 
still useful. I do not like this patch.

Will your next step be stripping ALL comments from the driver? The source would 
be a lot smaller that way! :)

Larry

Re: [PATCH v3 0/8] staging: r8188eu: fix and clean up some firmware code

[Larry Finger]

On 4/15/22 07:10, Michael Straube wrote:
> This series fixes wrong size of struct rt_firmware_hdr in the first
> patch and does some cleanups in rtl8188e_firmware_download() in the
> other patches.
> 
> Tested on x86_64 with Inter-Tech DMG-02.
> 
> v3:
> - Splitted the first patch into two separate patches.
> - Added back logging the firmware version only once.
> - Included the compile time check for size of rt_firmware from
>    patch 8/8 of v2 in the patch that replaces the hardcoded size.
> 
> v2:
> - Added a patch to check size of struct rt_firmware_hdr at compile time.
> 
> Michael Straube (8):
>    staging: r8188eu: fix struct rt_firmware_hdr
>    staging: r8188eu: convert u32 fields of rt_firmware_hdr to __le32
>    staging: r8188eu: clean up comments in struct rt_firmware_hdr
>    staging: r8188eu: rename fields of struct rt_firmware_hdr
>    staging: r8188eu: use sizeof instead of hardcoded firmware header size
>    staging: r8188eu: remove variables from rtl8188e_firmware_download()
>    staging: r8188eu: use pr_info_once() to log the firmware version
>    staging: r8188eu: check firmware header existence before access
> 
>   drivers/staging/r8188eu/core/rtw_fw.c | 79 ++++++++++-----------------
>   1 file changed, 29 insertions(+), 50 deletions(-)

Most of this is fine, other than the removal of in-line comments in patch 3/8.

Larry

Re: [PATCH v3 3/8] staging: r8188eu: clean up comments in struct rt_firmware_hdr

[Michael Straube]

On 4/15/22 17:44, Larry Finger wrote:
> On 4/15/22 07:10, Michael Straube wrote:
>> The comments in struct rt_firmware_hdr are not needed.
>> Remove them.
>>
>> Signed-off-by: Michael Straube <straube.linux@gmail.com>
>> ---
>> v3:
>> - no changes
>>
>> v2:
>> - no changes
>>
>>   drivers/staging/r8188eu/core/rtw_fw.c | 37 ++++++++-------------------
>>   1 file changed, 11 insertions(+), 26 deletions(-)
>>
>> diff --git a/drivers/staging/r8188eu/core/rtw_fw.c 
>> b/drivers/staging/r8188eu/core/rtw_fw.c
>> index 7cd08268f3b9..323e0c634c4e 100644
>> --- a/drivers/staging/r8188eu/core/rtw_fw.c
>> +++ b/drivers/staging/r8188eu/core/rtw_fw.c
>> @@ -14,37 +14,22 @@
>>       (le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x2300 ||    \
>>       (le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x88E0)
>> -/*  This structure must be careful with byte-ordering */
>> -
>>   struct rt_firmware_hdr {
>> -    /*  8-byte alinment required */
>> -    /*  LONG WORD 0 ---- */
>> -    __le16        Signature;    /* 92C0: test chip; 92C,
>> -                     * 88C0: test chip; 88C1: MP A-cut;
>> -                     * 92C1: MP A-cut */
>> -    u8        Category;    /*  AP/NIC and USB/PCI */
>> -    u8        Function;    /*  Reserved for different FW function
>> -                     *  indcation, for further use when
>> -                     *  driver needs to download different
>> -                     *  FW for different conditions */
>> -    __le16        Version;    /*  FW Version */
>> -    u8        Subversion;    /*  FW Subversion, default 0x00 */
>> +    __le16        Signature;
>> +    u8        Category;
>> +    u8        Function;
>> +    __le16        Version;
>> +    u8        Subversion;
>>       u8        Rsvd1;
>> -
>> -    /*  LONG WORD 1 ---- */
>> -    u8        Month;    /*  Release time Month field */
>> -    u8        Date;    /*  Release time Date field */
>> -    u8        Hour;    /*  Release time Hour field */
>> -    u8        Minute;    /*  Release time Minute field */
>> -    __le16        RamCodeSize;    /*  The size of RAM code */
>> +    u8        Month;
>> +    u8        Date;
>> +    u8        Hour;
>> +    u8        Minute;
>> +    __le16        RamCodeSize;
>>       u8        Foundry;
>>       u8        Rsvd2;
>> -
>> -    /*  LONG WORD 2 ---- */
>> -    __le32        SvnIdx;    /*  The SVN entry index */
>> +    __le32        SvnIdx;
>>       __le32        Rsvd3;
>> -
>> -    /*  LONG WORD 3 ---- */
>>       __le32        Rsvd4;
>>       __le32        Rsvd5;
>>   };
> 
> The comments "LONG WORD" are useless, but the comments describing the 
> fields are still useful. I do not like this patch.
> 

Hi Larry,

You are right the in-line comments are useful. I'll send v4 keeping
them.

You only mentioned the in-line comments, just to get it right this
time:

What about the "8-byte alignment required" comment? You said in another
thread that the __le16 references need alignment 4. Should I make the
struct __aligned(8) or at least __aligned(4)?

And about "/*  This structure must be careful with byte-ordering */" ?
I think it's obvious because of the __le16 and __le32 fields and can be
removed. Do you agree on that?

regards,
Michael

Re: [PATCH v3 3/8] staging: r8188eu: clean up comments in struct rt_firmware_hdr

[Larry Finger]

On 4/15/22 13:05, Michael Straube wrote:
> On 4/15/22 17:44, Larry Finger wrote:
>> On 4/15/22 07:10, Michael Straube wrote:
>>> The comments in struct rt_firmware_hdr are not needed.
>>> Remove them.
>>>
>>> Signed-off-by: Michael Straube <straube.linux@gmail.com>
>>> ---
>>> v3:
>>> - no changes
>>>
>>> v2:
>>> - no changes
>>>
>>>   drivers/staging/r8188eu/core/rtw_fw.c | 37 ++++++++-------------------
>>>   1 file changed, 11 insertions(+), 26 deletions(-)
>>>
>>> diff --git a/drivers/staging/r8188eu/core/rtw_fw.c 
>>> b/drivers/staging/r8188eu/core/rtw_fw.c
>>> index 7cd08268f3b9..323e0c634c4e 100644
>>> --- a/drivers/staging/r8188eu/core/rtw_fw.c
>>> +++ b/drivers/staging/r8188eu/core/rtw_fw.c
>>> @@ -14,37 +14,22 @@
>>>       (le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x2300 ||    \
>>>       (le16_to_cpu(_fwhdr->Signature) & 0xFFF0) == 0x88E0)
>>> -/*  This structure must be careful with byte-ordering */
>>> -
>>>   struct rt_firmware_hdr {
>>> -    /*  8-byte alinment required */
>>> -    /*  LONG WORD 0 ---- */
>>> -    __le16        Signature;    /* 92C0: test chip; 92C,
>>> -                     * 88C0: test chip; 88C1: MP A-cut;
>>> -                     * 92C1: MP A-cut */
>>> -    u8        Category;    /*  AP/NIC and USB/PCI */
>>> -    u8        Function;    /*  Reserved for different FW function
>>> -                     *  indcation, for further use when
>>> -                     *  driver needs to download different
>>> -                     *  FW for different conditions */
>>> -    __le16        Version;    /*  FW Version */
>>> -    u8        Subversion;    /*  FW Subversion, default 0x00 */
>>> +    __le16        Signature;
>>> +    u8        Category;
>>> +    u8        Function;
>>> +    __le16        Version;
>>> +    u8        Subversion;
>>>       u8        Rsvd1;
>>> -
>>> -    /*  LONG WORD 1 ---- */
>>> -    u8        Month;    /*  Release time Month field */
>>> -    u8        Date;    /*  Release time Date field */
>>> -    u8        Hour;    /*  Release time Hour field */
>>> -    u8        Minute;    /*  Release time Minute field */
>>> -    __le16        RamCodeSize;    /*  The size of RAM code */
>>> +    u8        Month;
>>> +    u8        Date;
>>> +    u8        Hour;
>>> +    u8        Minute;
>>> +    __le16        RamCodeSize;
>>>       u8        Foundry;
>>>       u8        Rsvd2;
>>> -
>>> -    /*  LONG WORD 2 ---- */
>>> -    __le32        SvnIdx;    /*  The SVN entry index */
>>> +    __le32        SvnIdx;
>>>       __le32        Rsvd3;
>>> -
>>> -    /*  LONG WORD 3 ---- */
>>>       __le32        Rsvd4;
>>>       __le32        Rsvd5;
>>>   };
>>
>> The comments "LONG WORD" are useless, but the comments describing the fields 
>> are still useful. I do not like this patch.
>>
> 
> Hi Larry,
> 
> You are right the in-line comments are useful. I'll send v4 keeping
> them.
> 
> You only mentioned the in-line comments, just to get it right this
> time:
> 
> What about the "8-byte alignment required" comment? You said in another
> thread that the __le16 references need alignment 4. Should I make the
> struct __aligned(8) or at least __aligned(4)?

Routines cpu_to_le16() and le16_to_cpu() require two-byte alignment. Similarly, 
the 32-bit versions need 4-byte alignment. The layout of the struct will ensure 
that as long as the entire struct has 4-byte alignment.

This struct is only used in rtl8188e_firmware_download() where it is created on 
the stack. That means it will be 8-byte aligned for x86_64 and 4-byle aligned on 
32-bit systems. I'm sure that Dan or GregKH will correct me if I got this wrong, 
but that should be sufficient. Making it __aligned(8) could waste 4 bytes on the 
stack for 32-bit systems. Using __aligned(4) would have no effect on any system.

I say remove the comment.

> 
> And about "/*  This structure must be careful with byte-ordering */" ?
> I think it's obvious because of the __le16 and __le32 fields and can be
> removed. Do you agree on that?

Using the __leNN implies little-endian, thus that comment is useless. Yes, I agree.


Larry