Commit afadbf4b authored by Stephen M. Cameron's avatar Stephen M. Cameron Committed by Jens Axboe

cciss: factor out cciss_find_board_params

cciss: factor out cciss_find_board_params
Signed-off-by: default avatarStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
parent da550321
......@@ -4072,6 +4072,30 @@ static int __devinit cciss_find_cfgtables(ctlr_info_t *h)
return 0;
}
/* Interrogate the hardware for some limits:
* max commands, max SG elements without chaining, and with chaining,
* SG chain block size, etc.
*/
static void __devinit cciss_find_board_params(ctlr_info_t *h)
{
h->max_commands = readl(&(h->cfgtable->MaxPerformantModeCommands));
h->nr_cmds = h->max_commands - 4; /* Allow room for some ioctls */
h->maxsgentries = readl(&(h->cfgtable->MaxSGElements));
/*
* Limit in-command s/g elements to 32 save dma'able memory.
* Howvever spec says if 0, use 31
*/
h->max_cmd_sgentries = 31;
if (h->maxsgentries > 512) {
h->max_cmd_sgentries = 32;
h->chainsize = h->maxsgentries - h->max_cmd_sgentries + 1;
h->maxsgentries--; /* save one for chain pointer */
} else {
h->maxsgentries = 31; /* default to traditional values */
h->chainsize = 0;
}
}
static int __devinit cciss_pci_init(ctlr_info_t *c)
{
int prod_index, err;
......@@ -4127,34 +4151,8 @@ static int __devinit cciss_pci_init(ctlr_info_t *c)
#ifdef CCISS_DEBUG
print_cfg_table(c->cfgtable);
#endif /* CCISS_DEBUG */
cciss_find_board_params(c);
/* Some controllers support Zero Memory Raid (ZMR).
* When configured in ZMR mode the number of supported
* commands drops to 64. So instead of just setting an
* arbitrary value we make the driver a little smarter.
* We read the config table to tell us how many commands
* are supported on the controller then subtract 4 to
* leave a little room for ioctl calls.
*/
c->max_commands = readl(&(c->cfgtable->MaxPerformantModeCommands));
c->maxsgentries = readl(&(c->cfgtable->MaxSGElements));
/*
* Limit native command to 32 s/g elements to save dma'able memory.
* Howvever spec says if 0, use 31
*/
c->max_cmd_sgentries = 31;
if (c->maxsgentries > 512) {
c->max_cmd_sgentries = 32;
c->chainsize = c->maxsgentries - c->max_cmd_sgentries + 1;
c->maxsgentries -= 1; /* account for chain pointer */
} else {
c->maxsgentries = 31; /* Default to traditional value */
c->chainsize = 0; /* traditional */
}
c->nr_cmds = c->max_commands - 4;
if ((readb(&c->cfgtable->Signature[0]) != 'C') ||
(readb(&c->cfgtable->Signature[1]) != 'I') ||
(readb(&c->cfgtable->Signature[2]) != 'S') ||
......
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