When I plug an ISA XT 8bit card into a 16bit compatible EISA
slot, the outb() operations seemingly stumble over each other
so we need to introduce a small delay after each outb()
operation. After this my MFM MiniScribe harddrive is properly
detected like this:
Detected 1 hard drive (using IRQ5 & DMA3)
xda: CHS=615/4/17
Signed-off-by: Linus Walleij <linus.wall...@linaro.org>
---
drivers/block/xd.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/block/xd.c b/drivers/block/xd.c
index ff54052..303e9f2 100644
--- a/drivers/block/xd.c
+++ b/drivers/block/xd.c
@@ -57,6 +57,8 @@
#include "xd.h"
+#define OUTB_DELAY 100
+
static DEFINE_MUTEX(xd_mutex);
static void __init do_xd_setup (int *integers);
#ifdef MODULE
@@ -485,7 +487,8 @@ static irqreturn_t xd_interrupt_handler(int irq, void
*dev_id)
#ifdef DEBUG_OTHER
printk("xd_interrupt_handler: interrupt detected\n");
#endif /* DEBUG_OTHER */
- outb(0,XD_CONTROL);
/* acknowledge interrupt */
+ outb(0,XD_CONTROL); /* acknowledge interrupt */
+ udelay(OUTB_DELAY);
wake_up(&xd_wait_int); /* and wake up sleeping processes */
return IRQ_HANDLED;
}
@@ -588,7 +591,9 @@ static u_int xd_command (u_char *command,u_char mode,u_char
*indata,u_char *outd
#endif /* DEBUG_COMMAND */
outb(0,XD_SELECT);
+ udelay(OUTB_DELAY);
outb(mode,XD_CONTROL);
+ udelay(OUTB_DELAY);
if (xd_waitport(XD_STATUS,STAT_SELECT,STAT_SELECT,timeout))
return (1);
@@ -602,8 +607,10 @@ static u_int xd_command (u_char *command,u_char
mode,u_char *indata,u_char *outd
if (mode == DMA_MODE) {
if (xd_wait_for_IRQ())
return (1);
- } else
+ } else {
outb(outdata ? *outdata++ : 0,XD_DATA);
+ udelay(OUTB_DELAY);
+ }
break;
case STAT_INPUT:
if (mode == DMA_MODE) {
@@ -617,6 +624,7 @@ static u_int xd_command (u_char *command,u_char mode,u_char
*indata,u_char *outd
break;
case STAT_COMMAND:
outb(command ? *command++ : 0,XD_DATA);
+ udelay(OUTB_DELAY);
break;
case STAT_COMMAND | STAT_INPUT:
complete = 1;
@@ -680,6 +688,7 @@ static void __init xd_dtc_init_controller (unsigned int
address)
xd_maxsectors = 0x01; /* my card seems to have trouble doing
multi-block transfers? */
outb(0,XD_RESET); /* reset the controller */
+ udelay(OUTB_DELAY);
}
@@ -773,6 +782,7 @@ static void __init xd_wd_init_controller (unsigned int
address)
xd_maxsectors = 0x01; /* this one doesn't wrap properly
either... */
outb(0,XD_RESET); /* reset the controller */
+ udelay(OUTB_DELAY);
msleep(XD_INIT_DISK_DELAY);
}
@@ -875,6 +885,7 @@ static void __init xd_seagate_init_controller (unsigned int
address)
xd_maxsectors = 0x40;
outb(0,XD_RESET); /* reset the controller */
+ udelay(OUTB_DELAY);
}
static void __init xd_seagate_init_drive (u_char drive)
@@ -908,6 +919,7 @@ static void __init xd_omti_init_controller (unsigned int
address)
xd_maxsectors = 0x40;
outb(0,XD_RESET); /* reset the controller */
+ udelay(OUTB_DELAY);
}
static void __init xd_omti_init_drive (u_char drive)
@@ -947,6 +959,7 @@ If you need non-standard settings use the xd=... command */
xd_maxsectors = 0x01;
outb(0,XD_RESET); /* reset the controller */
+ udelay(OUTB_DELAY);
msleep(XD_INIT_DISK_DELAY);
}
--
1.8.1.2
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