diff options
author | Cindy H Kao <cindy.h.kao@intel.com> | 2010-04-23 20:19:06 -0400 |
---|---|---|
committer | Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> | 2010-05-11 17:05:55 -0400 |
commit | d94401742dc662747db5bb9e444d353a4feba018 (patch) | |
tree | 1fa229f7d23b09b7b4c4e0262ed8e4e232876c26 | |
parent | 2354161dd33b204d36caa0bc48c95cc6c1a984fb (diff) |
wimax/i2400m: Reset the TX FIFO indices when allocating the TX FIFO in tx_setup()
This patch makes sure whenever tx_setup() is invoked during driver
initialization or device reset where TX FIFO is released and re-allocated,
the indices tx_in, tx_out, tx_msg_size, tx_sequence, tx_msg are properly
initialized.
When a device reset happens and the TX FIFO is released/re-allocated,
a new block of memory may be allocated for the TX FIFO, therefore tx_msg
should be cleared so that no any TX threads (tx_worker, tx) would access
to the out-of-date addresses.
Also, the TX threads use tx_in and tx_out to decide where to put the new
host-to-device messages and from where to copy them to the device HW FIFO,
these indices have to be cleared so after the TX FIFO is re-allocated during
the reset, the indices both refer to the head of the FIFO, ie. a new start.
The same rational applies to tx_msg_size and tx_sequence.
To protect the indices from being accessed by multiple threads simultaneously,
the lock tx_lock has to be obtained before the initializations and released
afterwards.
Signed-off-by: Cindy H Kao <cindy.h.kao@intel.com>
-rw-r--r-- | drivers/net/wimax/i2400m/tx.c | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/drivers/net/wimax/i2400m/tx.c b/drivers/net/wimax/i2400m/tx.c index 8561c0766535..21909e5d2010 100644 --- a/drivers/net/wimax/i2400m/tx.c +++ b/drivers/net/wimax/i2400m/tx.c | |||
@@ -877,27 +877,40 @@ EXPORT_SYMBOL_GPL(i2400m_tx_msg_sent); | |||
877 | * i2400m_tx_setup - Initialize the TX queue and infrastructure | 877 | * i2400m_tx_setup - Initialize the TX queue and infrastructure |
878 | * | 878 | * |
879 | * Make sure we reset the TX sequence to zero, as when this function | 879 | * Make sure we reset the TX sequence to zero, as when this function |
880 | * is called, the firmware has been just restarted. | 880 | * is called, the firmware has been just restarted. Same rational |
881 | * for tx_in, tx_out, tx_msg_size and tx_msg. We reset them since | ||
882 | * the memory for TX queue is reallocated. | ||
881 | */ | 883 | */ |
882 | int i2400m_tx_setup(struct i2400m *i2400m) | 884 | int i2400m_tx_setup(struct i2400m *i2400m) |
883 | { | 885 | { |
884 | int result; | 886 | int result = 0; |
887 | void *tx_buf; | ||
888 | unsigned long flags; | ||
885 | 889 | ||
886 | /* Do this here only once -- can't do on | 890 | /* Do this here only once -- can't do on |
887 | * i2400m_hard_start_xmit() as we'll cause race conditions if | 891 | * i2400m_hard_start_xmit() as we'll cause race conditions if |
888 | * the WS was scheduled on another CPU */ | 892 | * the WS was scheduled on another CPU */ |
889 | INIT_WORK(&i2400m->wake_tx_ws, i2400m_wake_tx_work); | 893 | INIT_WORK(&i2400m->wake_tx_ws, i2400m_wake_tx_work); |
890 | 894 | ||
891 | i2400m->tx_sequence = 0; | 895 | tx_buf = kmalloc(I2400M_TX_BUF_SIZE, GFP_ATOMIC); |
896 | if (tx_buf == NULL) { | ||
897 | result = -ENOMEM; | ||
898 | goto error_kmalloc; | ||
899 | } | ||
900 | |||
892 | /* Warn if the calculated buffer size exceeds I2400M_TX_BUF_SIZE. */ | 901 | /* Warn if the calculated buffer size exceeds I2400M_TX_BUF_SIZE. */ |
893 | BUILD_BUG_ON(I2400M_TX_PDU_TOTAL_SIZE > I2400M_TX_BUF_SIZE); | 902 | BUILD_BUG_ON(I2400M_TX_PDU_TOTAL_SIZE > I2400M_TX_BUF_SIZE); |
894 | i2400m->tx_buf = kmalloc(I2400M_TX_BUF_SIZE, GFP_KERNEL); | 903 | spin_lock_irqsave(&i2400m->tx_lock, flags); |
895 | if (i2400m->tx_buf == NULL) | 904 | i2400m->tx_sequence = 0; |
896 | result = -ENOMEM; | 905 | i2400m->tx_in = 0; |
897 | else | 906 | i2400m->tx_out = 0; |
898 | result = 0; | 907 | i2400m->tx_msg_size = 0; |
908 | i2400m->tx_msg = NULL; | ||
909 | i2400m->tx_buf = tx_buf; | ||
910 | spin_unlock_irqrestore(&i2400m->tx_lock, flags); | ||
899 | /* Huh? the bus layer has to define this... */ | 911 | /* Huh? the bus layer has to define this... */ |
900 | BUG_ON(i2400m->bus_tx_block_size == 0); | 912 | BUG_ON(i2400m->bus_tx_block_size == 0); |
913 | error_kmalloc: | ||
901 | return result; | 914 | return result; |
902 | 915 | ||
903 | } | 916 | } |