diff options
author | Stephen M. Cameron <scameron@beardog.cce.hp.com> | 2010-07-19 13:46:07 -0500 |
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committer | Jens Axboe <jaxboe@fusionio.com> | 2010-08-07 18:52:12 +0200 |
commit | b993313540de341e4c4df8f529d585e9400f43bd (patch) | |
tree | 1ba180653427a690b528e3801a8ed759782a019b /drivers/block/cciss.c | |
parent | 0f8a6a1e7b7162a51daee7df28f1b898da1a4165 (diff) |
cciss: factor out cciss_enter_performant_mode
cciss: factor out cciss_enter_performant_mode
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'drivers/block/cciss.c')
-rw-r--r-- | drivers/block/cciss.c | 98 |
1 files changed, 59 insertions, 39 deletions
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c index ee7cfde8a14..17e420c13b3 100644 --- a/drivers/block/cciss.c +++ b/drivers/block/cciss.c @@ -3830,54 +3830,36 @@ static void __devinit cciss_wait_for_mode_change_ack(ctlr_info_t *h) } } -static void __devinit cciss_put_controller_into_performant_mode(ctlr_info_t *h) +static __devinit void cciss_enter_performant_mode(ctlr_info_t *h) { - __u32 trans_support; + /* This is a bit complicated. There are 8 registers on + * the controller which we write to to tell it 8 different + * sizes of commands which there may be. It's a way of + * reducing the DMA done to fetch each command. Encoded into + * each command's tag are 3 bits which communicate to the controller + * which of the eight sizes that command fits within. The size of + * each command depends on how many scatter gather entries there are. + * Each SG entry requires 16 bytes. The eight registers are programmed + * with the number of 16-byte blocks a command of that size requires. + * The smallest command possible requires 5 such 16 byte blocks. + * the largest command possible requires MAXSGENTRIES + 4 16-byte + * blocks. Note, this only extends to the SG entries contained + * within the command block, and does not extend to chained blocks + * of SG elements. bft[] contains the eight values we write to + * the registers. They are not evenly distributed, but have more + * sizes for small commands, and fewer sizes for larger commands. + */ __u32 trans_offset; + int bft[8] = { 5, 6, 8, 10, 12, 20, 28, MAXSGENTRIES + 4}; /* * 5 = 1 s/g entry or 4k * 6 = 2 s/g entry or 8k * 8 = 4 s/g entry or 16k * 10 = 6 s/g entry or 24k */ - int bft[8] = { 5, 6, 8, 10, 12, 20, 28, MAXSGENTRIES + 4}; unsigned long register_value; - BUILD_BUG_ON(28 > MAXSGENTRIES + 4); - dev_dbg(&h->pdev->dev, "Trying to put board into Performant mode\n"); - /* Attempt to put controller into performant mode if supported */ - /* Does board support performant mode? */ - trans_support = readl(&(h->cfgtable->TransportSupport)); - if (!(trans_support & PERFORMANT_MODE)) - return; - - printk(KERN_WARNING "cciss%d: Placing controller into " - "performant mode\n", h->ctlr); - /* Performant mode demands commands on a 32 byte boundary - * pci_alloc_consistent aligns on page boundarys already. - * Just need to check if divisible by 32 - */ - if ((sizeof(CommandList_struct) % 32) != 0) { - printk(KERN_WARNING "%s %d %s\n", - "cciss info: command size[", - (int)sizeof(CommandList_struct), - "] not divisible by 32, no performant mode..\n"); - return; - } - - /* Performant mode ring buffer and supporting data structures */ - h->reply_pool = (__u64 *)pci_alloc_consistent( - h->pdev, h->max_commands * sizeof(__u64), - &(h->reply_pool_dhandle)); - - /* Need a block fetch table for performant mode */ - h->blockFetchTable = kmalloc(((h->maxsgentries+1) * - sizeof(__u32)), GFP_KERNEL); - - if ((h->reply_pool == NULL) || (h->blockFetchTable == NULL)) - goto clean_up; - h->reply_pool_wraparound = 1; /* spec: init to 1 */ /* Controller spec: zero out this buffer. */ @@ -3906,18 +3888,56 @@ static void __devinit cciss_put_controller_into_performant_mode(ctlr_info_t *h) writel(CFGTBL_Trans_Performant, &(h->cfgtable->HostWrite.TransportRequest)); - h->transMethod = CFGTBL_Trans_Performant; writel(CFGTBL_ChangeReq, h->vaddr + SA5_DOORBELL); cciss_wait_for_mode_change_ack(h); register_value = readl(&(h->cfgtable->TransportActive)); - if (!(register_value & CFGTBL_Trans_Performant)) { + if (!(register_value & CFGTBL_Trans_Performant)) printk(KERN_WARNING "cciss: unable to get board into" " performant mode\n"); +} + +static void __devinit cciss_put_controller_into_performant_mode(ctlr_info_t *h) +{ + __u32 trans_support; + + dev_dbg(&h->pdev->dev, "Trying to put board into Performant mode\n"); + /* Attempt to put controller into performant mode if supported */ + /* Does board support performant mode? */ + trans_support = readl(&(h->cfgtable->TransportSupport)); + if (!(trans_support & PERFORMANT_MODE)) + return; + + printk(KERN_WARNING "cciss%d: Placing controller into " + "performant mode\n", h->ctlr); + /* Performant mode demands commands on a 32 byte boundary + * pci_alloc_consistent aligns on page boundarys already. + * Just need to check if divisible by 32 + */ + if ((sizeof(CommandList_struct) % 32) != 0) { + printk(KERN_WARNING "%s %d %s\n", + "cciss info: command size[", + (int)sizeof(CommandList_struct), + "] not divisible by 32, no performant mode..\n"); return; } + /* Performant mode ring buffer and supporting data structures */ + h->reply_pool = (__u64 *)pci_alloc_consistent( + h->pdev, h->max_commands * sizeof(__u64), + &(h->reply_pool_dhandle)); + + /* Need a block fetch table for performant mode */ + h->blockFetchTable = kmalloc(((h->maxsgentries+1) * + sizeof(__u32)), GFP_KERNEL); + + if ((h->reply_pool == NULL) || (h->blockFetchTable == NULL)) + goto clean_up; + + cciss_enter_performant_mode(h); + /* Change the access methods to the performant access methods */ h->access = SA5_performant_access; + h->transMethod = CFGTBL_Trans_Performant; return; clean_up: |