lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

PCI: Add support for turning PCIe ECRC on or off

Browse Source 
Adds support for PCI Express transaction layer end-to-end CRC checking
(ECRC).  This patch will enable/disable ECRC checking by setting/clearing
the ECRC Check Enable and/or ECRC Generation Enable bits for devices that
support ECRC.

The ECRC setting is controlled by the "pci=ecrc=<policy>" command-line
option. If this option is not set or is set to 'bios", the enable and
generation bits are left in whatever state that firmware/BIOS set them to.
The "off" setting turns them off, and the "on" option turns them on (if the
device supports it).

Turning ECRC on or off can be a data integrity versus performance
tradeoff.  In theory, turning it on will catch more data errors, turning
it off means possibly better performance since CRC does not need to be
calculated by the PCIe hardware and packet sizes are reduced.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Andrew Patterson
2009-04-22 16:52:09 -06:00
committed by Jesse Barnes
parent f62795f1e8
commit 43c1640884
7 changed files with 174 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
include/linux/pci.h
View File

@ -878,6 +878,17 @@ static inline int pcie_aspm_enabled(void)
extern int pcie_aspm_enabled(void);
#endif
#ifndef CONFIG_PCIE_ECRC
static inline void pcie_set_ecrc_checking(struct pci_dev *dev)
{
return;
}
static inline void pcie_ecrc_get_policy(char *str) {};
#else
extern void pcie_set_ecrc_checking(struct pci_dev *dev);
extern void pcie_ecrc_get_policy(char *str);
#endif
#define pci_enable_msi(pdev) pci_enable_msi_block(pdev, 1)
#ifdef CONFIG_HT_IRQ