[SCSI] megaraid_{mm,mbox}: 64-bit DMA capability checker

This patch contains
- a fix for 64-bit DMA capability check in megaraid_{mm,mbox} driver.
- includes changes (going back to 32-bit DMA mask if 64-bit DMA mask
failes) suggested by James with previous patch.
- addition of SATA 150-4/6 as commented by Vasily Averin.

With patch, the driver access PCIconfiguration space with dedicated
offset to read a signature. If the signature read, it means that the
controller has capability to handle 64-bit DMA.
Without this patch, the driver used to blindly claim 64-bit DMA
capability.
The issue has been reported by Vasily Averin [vvs@sw.ru].
Thank you Vasily for the reporting.

Signed-Off By: Seokmann Ju <seokmann.ju@lsil.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

4 files changed, 94 insertions, 8 deletions

diff --git a/Documentation/scsi/ChangeLog.megaraid b/Documentation/scsi/ChangeLog.megaraid
index c173806c91fa..fd8939e0045d 100644
--- a/Documentation/scsi/ChangeLog.megaraid
+++ b/Documentation/scsi/ChangeLog.megaraid
@@ -1,3 +1,64 @@
+Release Date    : Fri May 19 09:31:45 EST 2006 - Seokmann Ju <sju@lsil.com>
+Current Version : 2.20.4.9 (scsi module), 2.20.2.6 (cmm module)
+Older Version   : 2.20.4.8 (scsi module), 2.20.2.6 (cmm module)
+
+1.      Fixed a bug in megaraid_init_mbox().
+        Customer reported "garbage in file on x86_64 platform".
+        Root Cause: the driver registered controllers as 64-bit DMA capable
+        for those which are not support it.
+        Fix: Made change in the function inserting identification machanism
+        identifying 64-bit DMA capable controllers.
+
+        > -----Original Message-----
+        > From: Vasily Averin [mailto:vvs@sw.ru]
+        > Sent: Thursday, May 04, 2006 2:49 PM
+        > To: linux-scsi@vger.kernel.org; Kolli, Neela; Mukker, Atul;
+        > Ju, Seokmann; Bagalkote, Sreenivas;
+        > James.Bottomley@SteelEye.com; devel@openvz.org
+        > Subject: megaraid_mbox: garbage in file
+        >
+        > Hello all,
+        >
+        > I've investigated customers claim on the unstable work of
+        > their node and found a
+        > strange effect: reading from some files leads to the
+        >  "attempt to access beyond end of device" messages.
+        >
+        > I've checked filesystem, memory on the node, motherboard BIOS
+        > version, but it
+        > does not help and issue still has been reproduced by simple
+        > file reading.
+        >
+        > Reproducer is simple:
+        >
+        > echo 0xffffffff >/proc/sys/dev/scsi/logging_level ;
+        > cat /vz/private/101/root/etc/ld.so.cache >/tmp/ttt  ;
+        > echo 0 >/proc/sys/dev/scsi/logging
+        >
+        > It leads to the following messages in dmesg
+        >
+        > sd_init_command: disk=sda, block=871769260, count=26
+        > sda : block=871769260
+        > sda : reading 26/26 512 byte blocks.
+        > scsi_add_timer: scmd: f79ed980, time: 7500, (c02b1420)
+        > sd 0:1:0:0: send 0xf79ed980                  sd 0:1:0:0:
+        >         command: Read (10): 28 00 33 f6 24 ac 00 00 1a 00
+        > buffer = 0xf7cfb540, bufflen = 13312, done = 0xc0366b40,
+        > queuecommand 0xc0344010
+        > leaving scsi_dispatch_cmnd()
+        > scsi_delete_timer: scmd: f79ed980, rtn: 1
+        > sd 0:1:0:0: done 0xf79ed980 SUCCESS        0 sd 0:1:0:0:
+        >         command: Read (10): 28 00 33 f6 24 ac 00 00 1a 00
+        > scsi host busy 1 failed 0
+        > sd 0:1:0:0: Notifying upper driver of completion (result 0)
+        > sd_rw_intr: sda: res=0x0
+        > 26 sectors total, 13312 bytes done.
+        > use_sg is 4
+        > attempt to access beyond end of device
+        > sda6: rw=0, want=1044134458, limit=951401367
+        > Buffer I/O error on device sda6, logical block 522067228
+        > attempt to access beyond end of device
+
 Release Date    : Mon Apr 11 12:27:22 EST 2006 - Seokmann Ju <sju@lsil.com>
 Current Version : 2.20.4.8 (scsi module), 2.20.2.6 (cmm module)
 Older Version   : 2.20.4.7 (scsi module), 2.20.2.6 (cmm module)
diff --git a/drivers/scsi/megaraid/mega_common.h b/drivers/scsi/megaraid/mega_common.h
index 4675343228ad..12e38125b123 100644
--- a/drivers/scsi/megaraid/mega_common.h
+++ b/drivers/scsi/megaraid/mega_common.h
@@ -37,6 +37,9 @@
 #define LSI_MAX_CHANNELS                16
 #define LSI_MAX_LOGICAL_DRIVES_64LD     (64+1)
 
+#define HBA_SIGNATURE_64_BIT            0x299
+#define PCI_CONF_AMISIG64               0xa4
+
 
 /**
  * scb_t - scsi command control block
diff --git a/drivers/scsi/megaraid/megaraid_mbox.c b/drivers/scsi/megaraid/megaraid_mbox.c
index 92715130ac09..e671af0b4f58 100644
--- a/drivers/scsi/megaraid/megaraid_mbox.c
+++ b/drivers/scsi/megaraid/megaraid_mbox.c
@@ -10,7 +10,7 @@
  *         2 of the License, or (at your option) any later version.
  *
  * FILE         : megaraid_mbox.c
- * Version      : v2.20.4.8 (Apr 11 2006)
+ * Version      : v2.20.4.9 (Jul 16 2006)
  *
  * Authors:
  *      Atul Mukker             <Atul.Mukker@lsil.com>
@@ -720,6 +720,7 @@ megaraid_init_mbox(adapter_t *adapter)
         struct pci_dev          *pdev;
         mraid_device_t          *raid_dev;
         int                     i;
+        uint32_t                magic64;
 
 
         adapter->ito    = MBOX_TIMEOUT;
@@ -863,12 +864,33 @@ megaraid_init_mbox(adapter_t *adapter)
 
         // Set the DMA mask to 64-bit. All supported controllers as capable of
         // DMA in this range
-        if (pci_set_dma_mask(adapter->pdev, DMA_64BIT_MASK) != 0) {
-
-                con_log(CL_ANN, (KERN_WARNING
-                        "megaraid: could not set DMA mask for 64-bit.\n"));
+        pci_read_config_dword(adapter->pdev, PCI_CONF_AMISIG64, &magic64);
+
+        if (((magic64 == HBA_SIGNATURE_64_BIT) &&
+                ((adapter->pdev->subsystem_device !=
+                PCI_SUBSYS_ID_MEGARAID_SATA_150_6) ||
+                (adapter->pdev->subsystem_device !=
+                PCI_SUBSYS_ID_MEGARAID_SATA_150_4))) ||
+                (adapter->pdev->vendor == PCI_VENDOR_ID_LSI_LOGIC &&
+                adapter->pdev->device == PCI_DEVICE_ID_VERDE) ||
+                (adapter->pdev->vendor == PCI_VENDOR_ID_LSI_LOGIC &&
+                adapter->pdev->device == PCI_DEVICE_ID_DOBSON) ||
+                (adapter->pdev->vendor == PCI_VENDOR_ID_LSI_LOGIC &&
+                adapter->pdev->device == PCI_DEVICE_ID_LINDSAY) ||
+                (adapter->pdev->vendor == PCI_VENDOR_ID_DELL &&
+                adapter->pdev->device == PCI_DEVICE_ID_PERC4_DI_EVERGLADES) ||
+                (adapter->pdev->vendor == PCI_VENDOR_ID_DELL &&
+                adapter->pdev->device == PCI_DEVICE_ID_PERC4E_DI_KOBUK)) {
+                if (pci_set_dma_mask(adapter->pdev, DMA_64BIT_MASK)) {
+                        con_log(CL_ANN, (KERN_WARNING
+                                "megaraid: DMA mask for 64-bit failed\n"));
 
-                goto out_free_sysfs_res;
+                        if (pci_set_dma_mask (adapter->pdev, DMA_32BIT_MASK)) {
+                                con_log(CL_ANN, (KERN_WARNING
+                                        "megaraid: 32-bit DMA mask failed\n"));
+                                goto out_free_sysfs_res;
+                        }
+                }
         }
 
         // setup tasklet for DPC
diff --git a/drivers/scsi/megaraid/megaraid_mbox.h b/drivers/scsi/megaraid/megaraid_mbox.h
index 868fb0ec93e7..2b5a3285f799 100644
--- a/drivers/scsi/megaraid/megaraid_mbox.h
+++ b/drivers/scsi/megaraid/megaraid_mbox.h
@@ -21,8 +21,8 @@
 #include "megaraid_ioctl.h"
 
 
-#define MEGARAID_VERSION        "2.20.4.8"
-#define MEGARAID_EXT_VERSION    "(Release Date: Mon Apr 11 12:27:22 EST 2006)"
+#define MEGARAID_VERSION        "2.20.4.9"
+#define MEGARAID_EXT_VERSION    "(Release Date: Sun Jul 16 12:27:22 EST 2006)"
 
 
 /*