On 09/02/2016 06:26 AM, Sven Eckelmann wrote:
On Freitag, 2. September 2016 13:13:20 CEST Arend Van Spriel wrote:
[...]
Do you have any recommendations where the firmware loading problems could
come from, and where we could start to debug? Any pointers would be
appreciated.
Hi Simon,
Could it be an endian issue?
Yes, it could be one (at least I've also guessed this - I could still be
completely wrong). But the problem is now to find a good starting point for
the debugging effort.
I've only looked at Simon's screen once while he gather USB dumps but didn't
spot any obvious at that time. There was also the problem that the comparison
dump looked already a lot different due to some timing differences.
I think Simon can give you later more details (when required).
Simon,
Yes, it is an endian issue. I can see part of the problem, but I do not have a
fix yet.
The firmware is read in as an array of bytes, thus it is effectively in
little-endian order. When it is written back to the device in routine
_rtl92c_fw_block_write(), the data output uses 32-bit writes. Of course, all
data supplied in all 2- and 4-byte writes is assumed to be in CPU order. As the
device needs the data to be little-endian, it will be byte swapped on BE
machines. As a result, the firmware is written out in the wrong byte order. I
think that this problem should be fixed with:
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192c/fw_common.c
b/drivers/net/wireless/realtek/rtlwifi/rtl8192c/fw_common.c
index 43fcb25..cd7ae70 100644
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8192c/fw_common.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192c/fw_common.c
@@ -74,18 +74,19 @@ static void _rtl92c_fw_block_write(struct ieee80211_hw *hw,
struct rtl_priv *rtlpriv = rtl_priv(hw);
u32 blocksize = sizeof(u32);
u8 *bufferptr = (u8 *)buffer;
- u32 *pu4byteptr = (u32 *)buffer;
+ __le32 *pu4byteptr = (__le32 *)buffer;
u32 i, offset, blockcount, remainsize;
+ u32 data;
blockcount = size / blocksize;
remainsize = size % blocksize;
for (i = 0; i < blockcount; i++) {
offset = i * blocksize;
+ data = le32_to_cpu(*(pu4byteptr + i));
rtl_write_dword(rtlpriv, (FW_8192C_START_ADDRESS + offset),
- *(pu4byteptr + i));
+ data);
}
-
if (remainsize) {
offset = blockcount * blocksize;
bufferptr += offset;
Unfortunately, applying the patch results in a checksum error on my PPC.
I'll let you know what I find.
Larry
