[PATCH] cciss: adds MSI and MSI-X support

This creates a new function, cciss_interrupt_mode called from
cciss_pci_init.  This function determines what type of interrupt vector to
use, i.e., MSI, MSI-X, or IO-APIC.

One noticeable difference is changing the interrupt field of the controller
struct to an array of 4 unsigned ints.  The Smart Array HW is capable of
generating 4 distinct interrupts depending on the transport method in use
during operation.  These are:

#define DOORBELL_INT 0
Used to notify the contoller of configuration updates. We only use
this feature when in polling mode.

#define PERF_MODE_INT 0
Used when the controller is in Performant Mode.

#define SIMPLE_MODE_INT 2
Used when the controller is in Simple Mode (current Linux implementation).

#define MEMQ_INT_MODE 3
Not used.

When using IO-APIC interrupts these 4 lines are OR'ed together so when any
one fires an interrupt an is generated.  In MSI or MSI-X mode this hardware
OR'ing is ignored.  We must register for our interrupt depending on what
mode the controller is running.  For Linux we use SIMPLE_MODE_INT
exclusively at this time.  Please consider this for inclusion.

Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/block/cciss.h b/drivers/block/cciss.h
index 3b0858c83897..ad45e581a91d 100644
--- a/drivers/block/cciss.h
+++ b/drivers/block/cciss.h
@@ -65,7 +65,6 @@ struct ctlr_info
         unsigned long io_mem_addr;
         unsigned long io_mem_length;
         CfgTable_struct __iomem *cfgtable;
-        unsigned int intr;
         int     interrupts_enabled;
         int     major;
         int     max_commands;
@@ -74,6 +73,13 @@ struct ctlr_info
         int     num_luns;
         int     highest_lun;
         int     usage_count;  /* number of opens all all minor devices */
+#       define DOORBELL_INT     0
+#       define PERF_MODE_INT    1
+#       define SIMPLE_MODE_INT  2
+#       define MEMQ_MODE_INT    3
+        unsigned int intr[4];
+        unsigned int msix_vector;
+        unsigned int msi_vector;
 
         // information about each logical volume
         drive_info_struct drv[CISS_MAX_LUN];