dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

RDMA/nes: Mitigate compatibility issue regarding PCIe write credits 

Under heavy load, there is an compatibility issue regarding PCIe write
credits with certain chipsets.  It can be mitigated by limiting read
requests to 256 Bytes.

This workaround is always enabled for Tbird2 on Gladius.  We also add
a module parameter to enable workaround for non-Gladius cards.

Signed-off-by: Chien Tung <chien.tin.tung@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Chien Tung 2008-11-02 21:40:55 -08:00 committed by Roland Dreier
parent 2e369544ac
commit 6336936600
2 changed files with 17 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/infiniband/hw/nes/nes.c
View File

@ -95,6 +95,10 @@ unsigned int wqm_quanta = 0x10000;
module_param(wqm_quanta, int, 0644);
MODULE_PARM_DESC(wqm_quanta, "WQM quanta");
static unsigned int limit_maxrdreqsz;
module_param(limit_maxrdreqsz, bool, 0644);
MODULE_PARM_DESC(limit_maxrdreqsz, "Limit max read request size to 256 Bytes");
LIST_HEAD(nes_adapter_list);
static LIST_HEAD(nes_dev_list);
@ -588,6 +592,18 @@ static int __devinit nes_probe(struct pci_dev *pcidev, const struct pci_device_i
nesdev->nesadapter->port_count;
}
if ((limit_maxrdreqsz ||
((nesdev->nesadapter->phy_type[0] == NES_PHY_TYPE_GLADIUS) &&
(hw_rev == NE020_REV1))) &&
(pcie_get_readrq(pcidev) > 256)) {
if (pcie_set_readrq(pcidev, 256))
printk(KERN_ERR PFX "Unable to set max read request"
" to 256 bytes\n");
else
nes_debug(NES_DBG_INIT, "Max read request size set"
" to 256 bytes\n");
}
tasklet_init(&nesdev->dpc_tasklet, nes_dpc, (unsigned long)nesdev);
/* bring up the Control QP */

1
drivers/infiniband/hw/nes/nes_hw.h
View File

@ -40,6 +40,7 @@
#define NES_PHY_TYPE_ARGUS 4
#define NES_PHY_TYPE_PUMA_1G 5
#define NES_PHY_TYPE_PUMA_10G 6
#define NES_PHY_TYPE_GLADIUS 7
#define NES_MULTICAST_PF_MAX 8