[PATCH 2/7] cciss: Inform controller we are using 32-bit tags.

From: Stephen M. Cameron
Date: Fri Mar 11 2011 - 15:59:17 EST


From: Stephen M. Cameron <scameron@xxxxxxxxxxxxxxxxxx>

Controller will DMA only 32-bits of the tag per command
on completion if it knows we are only using 32-bit tags.

Signed-off-by: Stephen M. Cameron <scameron@xxxxxxxxxxxxxxxxxx>
---
drivers/block/cciss.c | 25 +++++++++++++++----------
drivers/block/cciss_cmd.h | 1 +
2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 8c88944..66363f0 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -231,7 +231,7 @@ static const struct block_device_operations cciss_fops = {
*/
static void set_performant_mode(ctlr_info_t *h, CommandList_struct *c)
{
- if (likely(h->transMethod == CFGTBL_Trans_Performant))
+ if (likely(h->transMethod & CFGTBL_Trans_Performant))
c->busaddr |= 1 | (h->blockFetchTable[c->Header.SGList] << 1);
}

@@ -3136,10 +3136,13 @@ static inline u32 cciss_tag_to_index(u32 tag)
return tag >> DIRECT_LOOKUP_SHIFT;
}

-static inline u32 cciss_tag_discard_error_bits(u32 tag)
+static inline u32 cciss_tag_discard_error_bits(ctlr_info_t *h, u32 tag)
{
-#define CCISS_ERROR_BITS 0x03
- return tag & ~CCISS_ERROR_BITS;
+#define CCISS_PERF_ERROR_BITS ((1 << DIRECT_LOOKUP_SHIFT) - 1)
+#define CCISS_SIMPLE_ERROR_BITS 0x03
+ if (likely(h->transMethod & CFGTBL_Trans_Performant))
+ return tag & ~CCISS_PERF_ERROR_BITS;
+ return tag & ~CCISS_SIMPLE_ERROR_BITS;
}

static inline void cciss_mark_tag_indexed(u32 *tag)
@@ -3359,7 +3362,7 @@ static inline u32 next_command(ctlr_info_t *h)
{
u32 a;

- if (unlikely(h->transMethod != CFGTBL_Trans_Performant))
+ if (unlikely(!(h->transMethod & CFGTBL_Trans_Performant)))
return h->access.command_completed(h);

if ((*(h->reply_pool_head) & 1) == (h->reply_pool_wraparound)) {
@@ -3397,9 +3400,9 @@ static inline u32 process_nonindexed_cmd(ctlr_info_t *h, u32 raw_tag)
CommandList_struct *c = NULL;
__u32 busaddr_masked, tag_masked;

- tag_masked = cciss_tag_discard_error_bits(raw_tag);
+ tag_masked = cciss_tag_discard_error_bits(h, raw_tag);
list_for_each_entry(c, &h->cmpQ, list) {
- busaddr_masked = cciss_tag_discard_error_bits(c->busaddr);
+ busaddr_masked = cciss_tag_discard_error_bits(h, c->busaddr);
if (busaddr_masked == tag_masked) {
finish_cmd(h, c, raw_tag);
return next_command(h);
@@ -3751,7 +3754,8 @@ static void __devinit cciss_wait_for_mode_change_ack(ctlr_info_t *h)
}
}

-static __devinit void cciss_enter_performant_mode(ctlr_info_t *h)
+static __devinit void cciss_enter_performant_mode(ctlr_info_t *h,
+ u32 use_short_tags)
{
/* This is a bit complicated. There are 8 registers on
* the controller which we write to to tell it 8 different
@@ -3806,7 +3810,7 @@ static __devinit void cciss_enter_performant_mode(ctlr_info_t *h)
writel(0, &h->transtable->RepQCtrAddrHigh32);
writel(h->reply_pool_dhandle, &h->transtable->RepQAddr0Low32);
writel(0, &h->transtable->RepQAddr0High32);
- writel(CFGTBL_Trans_Performant,
+ writel(CFGTBL_Trans_Performant | use_short_tags,
&(h->cfgtable->HostWrite.TransportRequest));

writel(CFGTBL_ChangeReq, h->vaddr + SA5_DOORBELL);
@@ -3853,7 +3857,8 @@ static void __devinit cciss_put_controller_into_performant_mode(ctlr_info_t *h)
if ((h->reply_pool == NULL) || (h->blockFetchTable == NULL))
goto clean_up;

- cciss_enter_performant_mode(h);
+ cciss_enter_performant_mode(h,
+ trans_support & CFGTBL_Trans_use_short_tags);

/* Change the access methods to the performant access methods */
h->access = SA5_performant_access;
diff --git a/drivers/block/cciss_cmd.h b/drivers/block/cciss_cmd.h
index 35463d2..cd441be 100644
--- a/drivers/block/cciss_cmd.h
+++ b/drivers/block/cciss_cmd.h
@@ -56,6 +56,7 @@

#define CFGTBL_Trans_Simple 0x00000002l
#define CFGTBL_Trans_Performant 0x00000004l
+#define CFGTBL_Trans_use_short_tags 0x20000000l

#define CFGTBL_BusType_Ultra2 0x00000001l
#define CFGTBL_BusType_Ultra3 0x00000002l

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