diff options
Diffstat (limited to 'drivers/vme/bridges/vme_ca91cx42.c')
| -rw-r--r-- | drivers/vme/bridges/vme_ca91cx42.c | 29 |
1 files changed, 14 insertions, 15 deletions
diff --git a/drivers/vme/bridges/vme_ca91cx42.c b/drivers/vme/bridges/vme_ca91cx42.c index a06edbfa95ca..92b5719cd99b 100644 --- a/drivers/vme/bridges/vme_ca91cx42.c +++ b/drivers/vme/bridges/vme_ca91cx42.c @@ -869,14 +869,13 @@ static ssize_t ca91cx42_master_read(struct vme_master_resource *image, spin_lock(&image->lock); - /* The following code handles VME address alignment problem - * in order to assure the maximal data width cycle. - * We cannot use memcpy_xxx directly here because it - * may cut data transfer in 8-bits cycles, thus making - * D16 cycle impossible. - * From the other hand, the bridge itself assures that - * maximal configured data cycle is used and splits it - * automatically for non-aligned addresses. + /* The following code handles VME address alignment. We cannot use + * memcpy_xxx here because it may cut data transfers in to 8-bit + * cycles when D16 or D32 cycles are required on the VME bus. + * On the other hand, the bridge itself assures that the maximum data + * cycle configured for the transfer is used and splits it + * automatically for non-aligned addresses, so we don't want the + * overhead of needlessly forcing small transfers for the entire cycle. */ if ((uintptr_t)addr & 0x1) { *(u8 *)buf = ioread8(addr); @@ -896,9 +895,9 @@ static ssize_t ca91cx42_master_read(struct vme_master_resource *image, } count32 = (count - done) & ~0x3; - if (count32 > 0) { - memcpy_fromio(buf + done, addr + done, (unsigned int)count); - done += count32; + while (done < count32) { + *(u32 *)(buf + done) = ioread32(addr + done); + done += 4; } if ((count - done) & 0x2) { @@ -930,7 +929,7 @@ static ssize_t ca91cx42_master_write(struct vme_master_resource *image, spin_lock(&image->lock); /* Here we apply for the same strategy we do in master_read - * function in order to assure D16 cycle when required. + * function in order to assure the correct cycles. */ if ((uintptr_t)addr & 0x1) { iowrite8(*(u8 *)buf, addr); @@ -950,9 +949,9 @@ static ssize_t ca91cx42_master_write(struct vme_master_resource *image, } count32 = (count - done) & ~0x3; - if (count32 > 0) { - memcpy_toio(addr + done, buf + done, count32); - done += count32; + while (done < count32) { + iowrite32(*(u32 *)(buf + done), addr + done); + done += 4; } if ((count - done) & 0x2) { |