2009-04-01 18:14:31

by Paul Fulghum

Subject: [PATCH] synclink_gt add clock options

Add support for x8 asynchronous sample rate and
ability to specify base clock frequency.

Signed-off-by: Paul Fulghum <[email protected]>

--- a/include/linux/synclink.h 2009-03-23 18:12:14.000000000 -0500
+++ b/include/linux/synclink.h 2009-04-01 10:07:06.000000000 -0500
@@ -125,6 +125,7 @@
#define MGSL_MODE_MONOSYNC 3
#define MGSL_MODE_BISYNC 4
#define MGSL_MODE_RAW 6
+#define MGSL_MODE_BASE_CLOCK 7

#define MGSL_BUS_TYPE_ISA 1
#define MGSL_BUS_TYPE_EISA 2
--- a/drivers/char/synclink_gt.c 2009-03-23 18:12:14.000000000 -0500
+++ b/drivers/char/synclink_gt.c 2009-04-01 09:54:43.000000000 -0500
@@ -298,6 +298,7 @@ struct slgt_info {

unsigned int rbuf_fill_level;
unsigned int if_mode;
+ unsigned int base_clock;

/* device status */

@@ -1156,22 +1157,26 @@ static long set_params32(struct slgt_inf
return -EFAULT;

spin_lock(&info->lock);
- info->params.mode = tmp_params.mode;
- info->params.loopback = tmp_params.loopback;
- info->params.flags = tmp_params.flags;
- info->params.encoding = tmp_params.encoding;
- info->params.clock_speed = tmp_params.clock_speed;
- info->params.addr_filter = tmp_params.addr_filter;
- info->params.crc_type = tmp_params.crc_type;
- info->params.preamble_length = tmp_params.preamble_length;
- info->params.preamble = tmp_params.preamble;
- info->params.data_rate = tmp_params.data_rate;
- info->params.data_bits = tmp_params.data_bits;
- info->params.stop_bits = tmp_params.stop_bits;
- info->params.parity = tmp_params.parity;
+ if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
+ info->base_clock = tmp_params.clock_speed;
+ } else {
+ info->params.mode = tmp_params.mode;
+ info->params.loopback = tmp_params.loopback;
+ info->params.flags = tmp_params.flags;
+ info->params.encoding = tmp_params.encoding;
+ info->params.clock_speed = tmp_params.clock_speed;
+ info->params.addr_filter = tmp_params.addr_filter;
+ info->params.crc_type = tmp_params.crc_type;
+ info->params.preamble_length = tmp_params.preamble_length;
+ info->params.preamble = tmp_params.preamble;
+ info->params.data_rate = tmp_params.data_rate;
+ info->params.data_bits = tmp_params.data_bits;
+ info->params.stop_bits = tmp_params.stop_bits;
+ info->params.parity = tmp_params.parity;
+ }
spin_unlock(&info->lock);

- change_params(info);
+ program_hw(info);

return 0;
}
@@ -2561,10 +2566,13 @@ static int set_params(struct slgt_info *
return -EFAULT;

spin_lock_irqsave(&info->lock, flags);
- memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
+ if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
+ info->base_clock = tmp_params.clock_speed;
+ else
+ memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
spin_unlock_irqrestore(&info->lock, flags);

- change_params(info);
+ program_hw(info);

return 0;
}
@@ -3434,6 +3442,7 @@ static struct slgt_info *alloc_dev(int a
info->magic = MGSL_MAGIC;
INIT_WORK(&info->task, bh_handler);
info->max_frame_size = 4096;
+ info->base_clock = 14745600;
info->rbuf_fill_level = DMABUFSIZE;
info->port.close_delay = 5*HZ/10;
info->port.closing_wait = 30*HZ;
@@ -3781,7 +3790,7 @@ static void enable_loopback(struct slgt_
static void set_rate(struct slgt_info *info, u32 rate)
{
unsigned int div;
- static unsigned int osc = 14745600;
+ unsigned int osc = info->base_clock;

/* div = osc/rate - 1
*
@@ -4085,18 +4094,27 @@ static void async_mode(struct slgt_info
* 06 CTS IRQ enable
* 05 DCD IRQ enable
* 04 RI IRQ enable
- * 03 reserved, must be zero
+ * 03 0=16x sampling, 1=8x sampling
* 02 1=txd->rxd internal loopback enable
* 01 reserved, must be zero
* 00 1=master IRQ enable
*/
val = BIT15 + BIT14 + BIT0;
+ /* JCR[8] : 1 = x8 async mode feature available */
+ if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
+ ((info->base_clock < (info->params.data_rate * 16)) ||
+ (info->base_clock % (info->params.data_rate * 16)))) {
+ /* use 8x sampling */
+ val |= BIT3;
+ set_rate(info, info->params.data_rate * 8);
+ } else {
+ /* use 16x sampling */
+ set_rate(info, info->params.data_rate * 16);
+ }
wr_reg16(info, SCR, val);

slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);

- set_rate(info, info->params.data_rate * 16);
-
if (info->params.loopback)
enable_loopback(info);
}