[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>
diff --git a/drivers/block/cciss.h b/drivers/block/cciss.h
index 3b0858c..ad45e58 100644
--- a/drivers/block/cciss.h
+++ b/drivers/block/cciss.h
@@ -65,7 +65,6 @@
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 @@
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];