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-rw-r--r--drivers/serial/cpm_uart/cpm_uart.h6
-rw-r--r--drivers/serial/cpm_uart/cpm_uart_core.c19
2 files changed, 19 insertions, 6 deletions
diff --git a/drivers/serial/cpm_uart/cpm_uart.h b/drivers/serial/cpm_uart/cpm_uart.h
index 7274b527a3c..b754dcf0fda 100644
--- a/drivers/serial/cpm_uart/cpm_uart.h
+++ b/drivers/serial/cpm_uart/cpm_uart.h
@@ -76,18 +76,12 @@ struct uart_cpm_port {
unsigned char *tx_buf;
unsigned char *rx_buf;
u32 flags;
- void (*set_lineif)(struct uart_cpm_port *);
struct clk *clk;
u8 brg;
uint dp_addr;
void *mem_addr;
dma_addr_t dma_addr;
u32 mem_size;
- /* helpers */
- int baud;
- int bits;
- /* Keep track of 'odd' SMC2 wirings */
- int is_portb;
/* wait on close if needed */
int wait_closing;
/* value to combine with opcode to form cpm command */
diff --git a/drivers/serial/cpm_uart/cpm_uart_core.c b/drivers/serial/cpm_uart/cpm_uart_core.c
index f2b8adcc6c9..8692ff98fc0 100644
--- a/drivers/serial/cpm_uart/cpm_uart_core.c
+++ b/drivers/serial/cpm_uart/cpm_uart_core.c
@@ -72,6 +72,8 @@ static void cpm_uart_initbd(struct uart_cpm_port *pinfo);
/**************************************************************/
+#define HW_BUF_SPD_THRESHOLD 9600
+
/*
* Check, if transmit buffers are processed
*/
@@ -503,6 +505,11 @@ static void cpm_uart_set_termios(struct uart_port *port,
pr_debug("CPM uart[%d]:set_termios\n", port->line);
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
+ if (baud <= HW_BUF_SPD_THRESHOLD ||
+ (pinfo->port.state && pinfo->port.state->port.tty->low_latency))
+ pinfo->rx_fifosize = 1;
+ else
+ pinfo->rx_fifosize = RX_BUF_SIZE;
/* Character length programmed into the mode register is the
* sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
@@ -594,6 +601,17 @@ static void cpm_uart_set_termios(struct uart_port *port,
*/
bits++;
if (IS_SMC(pinfo)) {
+ /*
+ * MRBLR can be changed while an SMC/SCC is operating only
+ * if it is done in a single bus cycle with one 16-bit move
+ * (not two 8-bit bus cycles back-to-back). This occurs when
+ * the cp shifts control to the next RxBD, so the change does
+ * not take effect immediately. To guarantee the exact RxBD
+ * on which the change occurs, change MRBLR only while the
+ * SMC/SCC receiver is disabled.
+ */
+ out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize);
+
/* Set the mode register. We want to keep a copy of the
* enables, because we want to put them back if they were
* present.
@@ -604,6 +622,7 @@ static void cpm_uart_set_termios(struct uart_port *port,
out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits) | cval |
SMCMR_SM_UART | prev_mode);
} else {
+ out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
out_be16(&sccp->scc_psmr, (sbits << 12) | scval);
}