Stan's tests showed that PDMA improves sequential read performance by
a factor of 5 on a PowerBook 190. Last time I tried this on a
PowerBook 520 it didn't work, so let's not enable it there until
it can be tested with the present mac_scsi driver.

Tested-by: Stan Johnson <user...@yahoo.com>
Signed-off-by: Finn Thain <fth...@telegraphics.com.au>
---
 arch/m68k/mac/config.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/m68k/mac/config.c b/arch/m68k/mac/config.c
index 16cd5cea5207..95d548d8cc8a 100644
--- a/arch/m68k/mac/config.c
+++ b/arch/m68k/mac/config.c
@@ -713,7 +713,7 @@ static struct mac_model mac_data_table[] = {
                .name           = "PowerBook 190",
                .adb_type       = MAC_ADB_PB2,
                .via_type       = MAC_VIA_QUADRA,
-               .scsi_type      = MAC_SCSI_LATE,
+               .scsi_type      = MAC_SCSI_OLD,
                .ide_type       = MAC_IDE_BABOON,
                .scc_type       = MAC_SCC_QUADRA,
                .nubus_type     = MAC_NUBUS,
@@ -1077,9 +1077,7 @@ int __init mac_platform_init(void)
                        mac_scsi_old_rsrc, ARRAY_SIZE(mac_scsi_old_rsrc));
                break;
        case MAC_SCSI_LATE:
-               /* PDMA logic in 68040 PowerBooks is somehow different to
-                * '030 models. It's probably more like Quadras (see mac_esp).
-                */
+               /* XXX PDMA support for PowerBook 500 series needs testing */
                platform_device_register_simple("mac_scsi", 0,
                        mac_scsi_late_rsrc, ARRAY_SIZE(mac_scsi_late_rsrc));
                break;
-- 
2.13.6

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