iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Blackfin Serial Driver: annotate anomalies 05000215 and 05000099

Browse Source 
Add some comments for how these anomalies are addressed:

05000215 - UART TX Interrupt Masked Erroneously
We always clear ETBEI within last UART TX interrupt to end
a string.  It is always set when starting a new tx transfer.

05000099 - UART Line Status Register (UART_LSR) Bits Are Not Updated at
the Same Time
This anomaly affects driver only in POLL code where multi bits of
UART_LSR are checked. It doesn't affect current bfin_5xx.c driver.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sonic Zhang 2009-06-11 13:45:07 +01:00 committed by Linus Torvalds
parent 35ff693579
commit 0efa4f2c94
1 changed files with 14 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/serial/bfin_5xx.c
View File

@ -330,6 +330,11 @@ static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
/* Clear TFI bit */
UART_PUT_LSR(uart, TFI);
#endif
/* Anomaly notes:
* 05000215 - we always clear ETBEI within last UART TX
* interrupt to end a string. It is always set
* when start a new tx.
*/
UART_CLEAR_IER(uart, ETBEI);
return;
}
@ -528,6 +533,11 @@ static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
disable_dma(uart->tx_dma_channel);
clear_dma_irqstat(uart->tx_dma_channel);
/* Anomaly notes:
* 05000215 - we always clear ETBEI within last UART TX
* interrupt to end a string. It is always set
* when start a new tx.
*/
UART_CLEAR_IER(uart, ETBEI);
xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx += uart->tx_count;
@ -969,6 +979,10 @@ static void bfin_serial_reset_irda(struct uart_port *port)
}
#ifdef CONFIG_CONSOLE_POLL
/* Anomaly notes:
* 05000099 - Because we only use THRE in poll_put and DR in poll_get,
* losing other bits of UART_LSR is not a problem here.
*/
static void bfin_serial_poll_put_char(struct uart_port *port, unsigned char chr)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;