rt2x00 : hw support txdone implementation.
PATCH 1/1 rt2x00 : hw support txdone implementation.
This is an implementation that support WCID being the key_index coming from benoit without the change in the meaning of the tx fallback flag. It replaces the software only implementation by an implementation supporting HW encryption.
It fixes the mixes of usage of WCID behing set to the key_idx and then getting used as the entry index in the queue.
--- drivers/net/wireless/rt2x00/rt2800pci.c | 82 +++++++++++++------------------ 1 files changed, 34 insertions(+), 48 deletions(-)
drivers/net/wireless/rt2x00/rt2800pci.c +34 -48
@@ -920,76 +920,61 @@ static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) {struct data_queue *queue;struct queue_entry *entry; -struct queue_entry *entry_done; -struct queue_entry_priv_pci *entry_priv; +__le32 *txwi;struct txdone_entry_desc txdesc;u32 word;u32 reg; -u32 old_reg; -unsigned int type; -unsigned int index; -u16 mcs, real_mcs; +int i; +int wcid, ack, pid, tx_wcid, tx_ack, tx_pid; +u16 mcs, tx_mcs;/* -* During each loop we will compare the freshly read -* TX_STA_FIFO register value with the value read from -* the previous loop. If the 2 values are equal then -* we should stop processing because the chance it -* quite big that the device has been unplugged and -* we risk going into an endless loop. +* To avoid an endlees loop, we only read the TX_STA_FIFO register up +* to 256 times (this is enought to get all values from the FIFO). In +* normal situation, the loop is terminated when we reach a value with +* TX_STA_FIFO_VALID bit is 0. */ - old_reg =0 ; -while (1 ) { +for (i =0 ; i <256 ; i++) {rt2800_register_read (rt2x00dev,TX_STA_FIFO , ®);if (!rt2x00_get_field32 (reg,TX_STA_FIFO_VALID ))break ; -if (old_reg == reg) -break ; - old_reg = reg; + wcid =rt2x00_get_field32 (reg,TX_STA_FIFO_WCID ); + ack =rt2x00_get_field32 (reg,TX_STA_FIFO_TX_ACK_REQUIRED ); + pid =rt2x00_get_field32 (reg,TX_STA_FIFO_PID_TYPE );/* * Skip this entry when it contains an invalid * queue identication number. */ - type =rt2x00_get_field32 (reg,TX_STA_FIFO_PID_TYPE ) -1 ; -if (type >=QID_RX ) +if (pid <1 )continue ; - queue =rt2x00queue_get_queue (rt2x00dev, type); + queue =rt2x00queue_get_queue (rt2x00dev, pid -1 );if (unlikely (!queue))continue ;/* -* Skip this entry when it contains an invalid -* index number. +* Inside each queue, we process each entry in a chronological +* order. We first check that the queue is not empty. */ - index =rt2x00_get_field32 (reg,TX_STA_FIFO_WCID ) -1 ; -if (unlikely (index >= queue->limit)) +if (queue->length ==0 )continue ; + entry =rt2x00queue_get_entry (queue,Q_INDEX_DONE ); - entry = &queue->entries[index]; - entry_priv = entry->priv_data; -rt2x00_desc_read ((__le32 *)entry->skb->data,0 , &word); - - entry_done =rt2x00queue_get_entry (queue,Q_INDEX_DONE ); -while (entry != entry_done) { -/* -* Catch up. -* Just report any entries we missed as failed. -*/ -WARNING (rt2x00dev, -"TX status report missed for entry %d\n" , - entry_done->entry_idx); - - txdesc.flags =0 ; -__set_bit (TXDONE_UNKNOWN , &txdesc.flags); - txdesc.retry =0 ; - -rt2x00lib_txdone (entry_done, &txdesc); - entry_done =rt2x00queue_get_entry (queue,Q_INDEX_DONE ); - } +/* Check if we got a match by looking at WCID/ACK/PID +* fields */ + txwi = (__le32 *)(entry->skb->data - + rt2x00dev->ops->extra_tx_headroom); + +rt2x00_desc_read (txwi,1 , &word); + tx_wcid =rt2x00_get_field32 (word,TXWI_W1_WIRELESS_CLI_ID ); + tx_ack =rt2x00_get_field32 (word,TXWI_W1_ACK ); + tx_pid =rt2x00_get_field32 (word,TXWI_W1_PACKETID ); + +if ((wcid != tx_wcid) || (ack != tx_ack) || (pid != tx_pid)) +WARNING (rt2x00dev,"invalid TX_STA_FIFO content\n" );/* * Obtain the status about this packet.
@@ -1010,10 +995,11 @@ static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev)* we have mcs = tx_mcs - 1. So the number of * retry is (tx_mcs - mcs). */ - mcs =rt2x00_get_field32 (word,TXWI_W0_MCS ); - real_mcs =rt2x00_get_field32 (reg,TX_STA_FIFO_MCS ); + mcs =rt2x00_get_field32 (reg,TX_STA_FIFO_MCS ); +rt2x00_desc_read (txwi,0 , &word); + tx_mcs =rt2x00_get_field32 (word,TXWI_W0_MCS );__set_bit (TXDONE_FALLBACK , &txdesc.flags); - txdesc.retry = mcs -min (mcs, real_mcs); + txdesc.retry = tx_mcs -min (tx_mcs, mcs);rt2x00lib_txdone (entry, &txdesc); }
Signature · 1 line
1.7.0
Quoted 2 lines · Alban Browaeys
This is an implementation that support WCID being the
key_indexcoming from benoit without the change in the meaning of the tx fallback flag.
This text is hard to understand without context. Please use a description for the changes contained in the patch, not for the circumstances around it. The same applies to the subject. A space before ":" is unnecessary.
Quoted 2 lines
It replaces the software only implementation by an implementation supporting HW encryption.
So, I guess rt2800pci_txdone() would not work correctly if hardware encryption is used? Perhaps that should be explained.
Quoted 2 lines
It fixes the mixes of usage of WCID behing set to the
key_idxand then getting used as the entry index in the queue.
Maybe WCID could be expanded at least once? "behing" must be a typo.
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 935
Quoted 11 lines
/*
drivers/net/wireless/rt2x00/rt2800pci.c +4
-6-* During each loop we will compare the freshly read -* TX_STA_FIFO register value with the value read from -* the previous loop. If the 2 values are equal then -* we should stop processing because the chance it -* quite big that the device has been unplugged and -* we risk going into an endless loop. +* To avoid an endlees loop, we only read the TX_STA_FIFO register up +* to 256 times (this is enought to get all values from the FIFO). In +* normal situation, the loop is terminated when we reach a value with +* TX_STA_FIFO_VALID bit is 0.
Please spell check your comments.
I think using a different way for terminating the loop is a completely separate issue not related to the hardware crypto support. It should be explained why the old code needs to be changed.
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 952
Quoted 8 lines
/*
* Skip this entry when it contains an invalid
* queue identication number.
*/drivers/net/wireless/rt2x00/rt2800pci.c +1
-2- type =rt2x00_get_field32 (reg,TX_STA_FIFO_PID_TYPE ) -1 ; -if (type >=QID_RX ) +if (pid <1 )continue ;
I'm concerned that you are killing a valid check here. pid should be between 1 and QID_RX (inclusively).
It looks like you are replacing the existing code with your code instead of improving it with a new check. That alone could be a reason to reject your patch.
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 984
Quoted 7 lines
drivers/net/wireless/rt2x00/rt2800pci.c +0
-7-/* -* Catch up. -* Just report any entries we missed as failed. -*/ -WARNING (rt2x00dev, -"TX status report missed for entry %d\n" , - entry_done->entry_idx);
I'm concerned that you are removing this check. Is this condition impossible now or we just cannot detect it anymore?
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 1002
Quoted 8 lines
drivers/net/wireless/rt2x00/rt2800pci.c +4
-3- mcs =rt2x00_get_field32 (word,TXWI_W0_MCS ); - real_mcs =rt2x00_get_field32 (reg,TX_STA_FIFO_MCS ); + mcs =rt2x00_get_field32 (reg,TX_STA_FIFO_MCS ); +rt2x00_desc_read (txwi,0 , &word); + tx_mcs =rt2x00_get_field32 (word,TXWI_W0_MCS );__set_bit (TXDONE_FALLBACK , &txdesc.flags); - txdesc.retry = mcs -min (mcs, real_mcs); + txdesc.retry = tx_mcs -min (tx_mcs, mcs);
Maybe you could avoid renaming and redefining variables to make your patch more readable? Alternatively, you could do the renaming first in a separate patch. You can use interdiff to create a difference between patches i.e. subtract the cleanups from the main patch.
Signature · 2 lines
Regards, Pavel Roskin
Quoted 11 lines · Pavel Roskin
Quoted 3 lines · Alban Browaeys
This is an implementation that support WCID being the
key_indexcoming from benoit without the change in the meaning of the tx fallback flag.This text is hard to understand without context. Please use a description for the changes contained in the patch, not for the circumstances around it. The same applies to the subject. A space before ":" is unnecessary.
Fixing it.
Quoted 7 lines
Quoted 3 lines
It replaces the software only implementation by an implementation supporting HW encryption.
So, I guess
rt2800pci_txdone()would not work correctly if hardware encryption is used? Perhaps that should be explained.
Explain that HW encryption is not working with current code ? Well it cannot work at all . At least txdone read WCID (WIRLESS_CLI_ID as written in rt2800pci_write_tx_desc as the key index:
rt2x00_set_field32(&word, TXWI_W1_WIRELESS_CLI_ID,
test_bit(ENTRY_TXD_ENCRYPT, &txdesc->flags) ?
txdesc->key_idx : 0xff);then in rt2800pci_txdone we read it as the queue entry index:
index = rt2x00_get_field32(reg, TX_STA_FIFO_WCID) - 1;
As Josef also found out this leads to a mess:
"that doesn't even work most of the time. I seperated out all of the TX_STA_FIFO reading stuff and either TX_STA_FIFO_VALID would be 0, TX_STA_FIFO_TX_ACK_REQUIRED would be 0, or TX_STA_FIFO_WCID would be 254, which is way higher than the queue limit. So basically it gives us crap statistics."
http://article.gmane.org/gmane.linux.kernel.wireless.general/46713
Quoted 6 lines
Quoted 3 lines
It fixes the mixes of usage of WCID behing set to the
key_idxand then getting used as the entry index in the queue.Maybe WCID could be expanded at least once? "behing" must be a typo.
WCID is TX_STA_FIFO_WCID in the code. Do you mean I should use TX_STA_FIFO_WCID in the comment ? Or WIRELESS_CLI_ID as to what it means (and the constant used in write_tx_desc). Both are the same one is used for writing it , the other for reading it. Out of knowing which one to use in the comment I used WCID.
Quoted 31 lines
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 935
Quoted 12 lines
/*drivers/net/wireless/rt2x00/rt2800pci.c +4
-6-* During each loop we will compare the freshly read -* TX_STA_FIFO register value with the value read from -* the previous loop. If the 2 values are equal then -* we should stop processing because the chance it -* quite big that the device has been unplugged and -* we risk going into an endless loop. +* To avoid an endlees loop, we only read the TX_STA_FIFO register up +* to 256 times (this is enought to get all values from the FIFO). In +* normal situation, the loop is terminated when we reach a value with +* TX_STA_FIFO_VALID bit is 0. Please spell check your comments.
I think using a different way for terminating the loop is a completely separate issue not related to the hardware crypto support. It should be explained why the old code needs to be changed.
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 952
Quoted 9 lines
/*
* Skip this entry when it contains an invalid
* queue identication number.
*/drivers/net/wireless/rt2x00/rt2800pci.c +1
-2- type =rt2x00_get_field32 (reg,TX_STA_FIFO_PID_TYPE ) -1 ; -if (type>=QID_RX ) +if (pid<1 )continue ;I'm concerned that you are killing a valid check here. pid should be between 1 and
QID_RX(inclusively).
Quoted 5 lines
It looks like you are replacing the existing code with your code instead of improving it with a new check. That alone could be a reason to reject your patch.
Thank you I did not noticed that (the check was pid < 1 back when the patch was made. This rewrite of the check is more of a merge artifact.
http://rt2x00.serialmonkey.com/pipermail/users_rt2x00.serialmonkey.com/2009-August/000210.html
Quoted 12 lines
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 984
Quoted 8 lines
drivers/net/wireless/rt2x00/rt2800pci.c +0
-7-/* -* Catch up. -* Just report any entries we missed as failed. -*/ -WARNING (rt2x00dev, -"TX status report missed for entry %d\n" , - entry_done->entry_idx);I'm concerned that you are removing this check. Is this condition impossible now or we just cannot detect it anymore?
Both.
Quoted 5 lines
Quoted 5 lines
drivers/net/wireless/rt2x00/rt2800pci.c +3
-2- mcs =rt2x00_get_field32 (word,TXWI_W0_MCS ); - real_mcs =rt2x00_get_field32 (reg,TX_STA_FIFO_MCS ); + mcs =rt2x00_get_field32 (reg,TX_STA_FIFO_MCS ); +rt2x00_desc_read (txwi,0 ,&word); + tx_mcs =rt2x00_get_field32 (word,TXWI_W0_MCS );
Quoted 10 lines
drivers/net/wireless/rt2x00/rt2800pci.c static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) · line 1002
Quoted 4 lines
__set_bit(TXDONE_FALLBACK,&txdesc.flags);drivers/net/wireless/rt2x00/rt2800pci.c +1
-1- txdesc.retry = mcs -min (mcs, real_mcs); + txdesc.retry = tx_mcs -min (tx_mcs, mcs);Maybe you could avoid renaming and redefining variables to make your patch more readable? Alternatively, you could do the renaming first in a separate patch. You can use interdiff to create a difference between patches i.e. subtract the cleanups from the main patch.
Renaming will be removed.