----Next_Part(Tue_Nov__9_16:34:30_2004_916)--
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

Hmm...

some more thinking led me to come to think of the bus_space_barrier()
function and that it might be required between the two bus_space_read_2
calls in quick succession in isp_pci_rd_debounced().  So, modifying the
diff as shown below moved the problem to somewhere else...

I now got, while trying:

kveite# dd of=/dev/null bs=8k count=100 if=/dev/rsd2a
100+0 records in
100+0 records out
819200 bytes transferred in 0.067 secs (12226865 bytes/sec)
kveite# dd of=/dev/null bs=8k count=1000 if=/dev/rsd2a
1000+0 records in
1000+0 records out
8192000 bytes transferred in 0.556 secs (14733812 bytes/sec)
kveite# dd of=/dev/null bs=8k count=10000 if=/dev/rsd2a
dd: /dev/rsd2a: Input/output error
1062+0 records in
1062+0 records out
8699904 bytes transferred in 0.716 secs (12150703 bytes/sec)
kveite# 

on the console:

isp0: DMA error for command on 0.34.0
isp0: BOTCHED cmd for 0.34.0 cmd 0x8 datalen 8192
sd2(isp0:0:34:0): generic HBA error

Hm!

However, a subsequent attempt succeeded:

kveite# dd of=/dev/null bs=8k count=10000 if=/dev/rsd2a
10000+0 records in
10000+0 records out
81920000 bytes transferred in 5.424 secs (15103244 bytes/sec)
kveite# 

but that was perhaps just pure luck?

Any hints for this one?

Regards,

- Havard

----Next_Part(Tue_Nov__9_16:34:30_2004_916)--
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

Index: isp_pci.c
===================================================================
RCS file: /cvsroot/src/sys/dev/pci/isp_pci.c,v
retrieving revision 1.91
diff -u -u -p -r1.91 isp_pci.c
--- isp_pci.c   10 Mar 2004 22:42:47 -0000      1.91
+++ isp_pci.c   9 Nov 2004 15:22:33 -0000
@@ -698,10 +698,17 @@ isp_pci_attach(struct device *parent, st
        (((struct isp_pcisoftc *)a)->pci_poff[((x) & _BLK_REG_MASK) >> \
        _BLK_REG_SHFT] + ((x) & 0xff))
 
+#ifndef BUS_SPACE_BARRIER_READ_BEFORE_READ
+#define BUS_SPACE_BARRIER_READ_BEFORE_READ BUS_SPACE_BARRIER_READ
+#endif
+
 #define        BXR2(pcs, off)          \
        bus_space_read_2(pcs->pci_st, pcs->pci_sh, off)
 #define        BXW2(pcs, off, v)       \
        bus_space_write_2(pcs->pci_st, pcs->pci_sh, off, v)
+#define BXRBARRIER(pcs, off)   \
+       bus_space_barrier(pcs->pci_st, pcs->pci_sh, off, 2,  \
+               BUS_SPACE_BARRIER_READ_BEFORE_READ)
 
 
 static INLINE int
@@ -713,9 +720,11 @@ isp_pci_rd_debounced(struct ispsoftc *is
 
        do {
                val0 = BXR2(pcs, IspVirt2Off(isp, off));
+               BXRBARRIER(pcs, IspVirt2Off(isp, off));
                val1 = BXR2(pcs, IspVirt2Off(isp, off));
        } while (val0 != val1 && ++i < 1000);
        if (val0 != val1) {
+               printf("isp_pci de-bounce spin-out\n");
                return (1);
        }
        *rp = val0;
@@ -732,7 +741,7 @@ isp_pci_rd_isr(struct ispsoftc *isp, u_i
     u_int16_t *semap, u_int16_t *mbp)
 {
        struct isp_pcisoftc *pcs = (struct isp_pcisoftc *) isp;
-       u_int16_t isr, sema;
+       u_int16_t isr, sema, oisr, osema;
 
        if (IS_2100(isp)) {
                if (isp_pci_rd_debounced(isp, BIU_ISR, &isr)) {
@@ -746,15 +755,21 @@ isp_pci_rd_isr(struct ispsoftc *isp, u_i
                sema = BXR2(pcs, IspVirt2Off(isp, BIU_SEMA));
        }
        isp_prt(isp, ISP_LOGDEBUG3, "ISR 0x%x SEMA 0x%x", isr, sema);
+       oisr = isr;
+       osema = sema;
        isr &= INT_PENDING_MASK(isp);
        sema &= BIU_SEMA_LOCK;
        if (isr == 0 && sema == 0) {
+               printf("isp_pci_rd_isr: isr == 0 && sema == 0 (after mask)\n");
+               printf("isp_pci_rd_isr: isr == 0x%x, sema == 0x%x\n",
+                       oisr, osema);
                return (0);
        }
        *isrp = isr;
        if ((*semap = sema) != 0) {
                if (IS_2100(isp)) {
                        if (isp_pci_rd_debounced(isp, OUTMAILBOX0, mbp)) {
+                               printf("isp_pci_rd_isr: failed mailbox read\n");
                                return (0);
                        }
                } else {

----Next_Part(Tue_Nov__9_16:34:30_2004_916)----