aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/tty/serial/68328serial.c
diff options
context:
space:
mode:
authorJiri Slaby <jslaby@suse.cz>2012-04-02 13:54:39 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-04-09 12:02:44 -0700
commit1bb2687c3bad13a061e98887bdfb1a6b9ad79542 (patch)
treebe58f831907fef67f96804a3b80059eae44c7368 /drivers/tty/serial/68328serial.c
parentTTY: 68328serial, use ulong flags for interrupts status (diff)
downloadlinux-dev-1bb2687c3bad13a061e98887bdfb1a6b9ad79542.tar.xz
linux-dev-1bb2687c3bad13a061e98887bdfb1a6b9ad79542.zip
TTY: 68328serial, remove 68328serial.h
All the needed stuff is moved to 68328serial.c now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: linux-m68k@lists.linux-m68k.org Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/68328serial.c')
-rw-r--r--drivers/tty/serial/68328serial.c79
1 files changed, 76 insertions, 3 deletions
diff --git a/drivers/tty/serial/68328serial.c b/drivers/tty/serial/68328serial.c
index f0d5039a7b34..116d932401ed 100644
--- a/drivers/tty/serial/68328serial.c
+++ b/drivers/tty/serial/68328serial.c
@@ -57,8 +57,6 @@
#endif /* CONFIG_M68VZ328 */
#endif /* CONFIG_M68EZ328 */
-#include "68328serial.h"
-
/* Turn off usage of real serial interrupt code, to "support" Copilot */
#ifdef CONFIG_XCOPILOT_BUGS
#undef USE_INTS
@@ -66,9 +64,84 @@
#define USE_INTS
#endif
+/*
+ * I believe this is the optimal setting that reduces the number of interrupts.
+ * At high speeds the output might become a little "bursted" (use USTCNT_TXHE
+ * if that bothers you), but in most cases it will not, since we try to
+ * transmit characters every time rs_interrupt is called. Thus, quite often
+ * you'll see that a receive interrupt occures before the transmit one.
+ * -- Vladimir Gurevich
+ */
+#define USTCNT_TX_INTR_MASK (USTCNT_TXEE)
+
+/*
+ * 68328 and 68EZ328 UARTS are a little bit different. EZ328 has special
+ * "Old data interrupt" which occures whenever the data stay in the FIFO
+ * longer than 30 bits time. This allows us to use FIFO without compromising
+ * latency. '328 does not have this feature and without the real 328-based
+ * board I would assume that RXRE is the safest setting.
+ *
+ * For EZ328 I use RXHE (Half empty) interrupt to reduce the number of
+ * interrupts. RXFE (receive queue full) causes the system to lose data
+ * at least at 115200 baud
+ *
+ * If your board is busy doing other stuff, you might consider to use
+ * RXRE (data ready intrrupt) instead.
+ *
+ * The other option is to make these INTR masks run-time configurable, so
+ * that people can dynamically adapt them according to the current usage.
+ * -- Vladimir Gurevich
+ */
+
+/* (es) */
+#if defined(CONFIG_M68EZ328) || defined(CONFIG_M68VZ328)
+#define USTCNT_RX_INTR_MASK (USTCNT_RXHE | USTCNT_ODEN)
+#elif defined(CONFIG_M68328)
+#define USTCNT_RX_INTR_MASK (USTCNT_RXRE)
+#else
+#error Please, define the Rx interrupt events for your CPU
+#endif
+/* (/es) */
+
+/*
+ * This is our internal structure for each serial port's state.
+ *
+ * For definitions of the flags field, see serial.h
+ */
+struct m68k_serial {
+ char is_cons; /* Is this our console. */
+ int magic;
+ int baud_base;
+ int port;
+ int irq;
+ int flags; /* defined in tty.h */
+ int type; /* UART type */
+ struct tty_struct *tty;
+ int custom_divisor;
+ int x_char; /* xon/xoff character */
+ int close_delay;
+ unsigned short closing_wait;
+ int line;
+ int count; /* # of fd on device */
+ int blocked_open; /* # of blocked opens */
+ unsigned char *xmit_buf;
+ int xmit_head;
+ int xmit_tail;
+ int xmit_cnt;
+ wait_queue_head_t open_wait;
+ wait_queue_head_t close_wait;
+};
+
+#define SERIAL_MAGIC 0x5301
+
+/*
+ * Define the number of ports supported and their irqs.
+ */
+#define NR_PORTS 1
+
static struct m68k_serial m68k_soft[NR_PORTS];
-static unsigned int uart_irqs[NR_PORTS] = UART_IRQ_DEFNS;
+static unsigned int uart_irqs[NR_PORTS] = { UART_IRQ_NUM };
/* multiple ports are contiguous in memory */
m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;