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author | Chris Metcalf <cmetcalf@tilera.com> | 2010-11-02 12:05:10 -0400 |
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committer | Chris Metcalf <cmetcalf@tilera.com> | 2010-11-24 13:13:49 -0500 |
commit | f02cbbe657939489347cbda598401a56913ffcbd (patch) | |
tree | 0d21e68d899958e6549f908b0c715c6f37200027 /drivers/pci/quirks.c | |
parent | e5a06939736277c54a68ae275433db55b99d187c (diff) | |
download | blackbird-obmc-linux-f02cbbe657939489347cbda598401a56913ffcbd.tar.gz blackbird-obmc-linux-f02cbbe657939489347cbda598401a56913ffcbd.zip |
pci root complex: support for tile architecture
This change enables PCI root complex support for TILEPro. Unlike
TILE-Gx, TILEPro has no support for memory-mapped I/O, so the PCI
support consists of hypervisor upcalls for PIO, DMA, etc. However,
the performance is fine for the devices we have tested with so far
(1Gb Ethernet, SATA, etc.).
The <asm/io.h> header was tweaked to be a little bit more aggressive
about disabling attempts to map/unmap IO port space. The hacky
<asm/pci-bridge.h> header was rolled into the <asm/pci.h> header
and the result was simplified. Both of the latter two headers were
preliminary versions not meant for release before now - oh well.
There is one quirk for our TILEmpower platform, which accidentally
negotiates up to 5GT and needs to be kicked down to 2.5GT.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'drivers/pci/quirks.c')
-rw-r--r-- | drivers/pci/quirks.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index f5c63fe9db5c..6f9350cabbd5 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2136,6 +2136,24 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82865_HB, DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82875_HB, quirk_unhide_mch_dev6); +#ifdef CONFIG_TILE +/* + * The Tilera TILEmpower platform needs to set the link speed + * to 2.5GT(Giga-Transfers)/s (Gen 1). The default link speed + * setting is 5GT/s (Gen 2). 0x98 is the Link Control2 PCIe + * capability register of the PEX8624 PCIe switch. The switch + * supports link speed auto negotiation, but falsely sets + * the link speed to 5GT/s. + */ +static void __devinit quirk_tile_plx_gen1(struct pci_dev *dev) +{ + if (tile_plx_gen1) { + pci_write_config_dword(dev, 0x98, 0x1); + mdelay(50); + } +} +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_PLX, 0x8624, quirk_tile_plx_gen1); +#endif /* CONFIG_TILE */ #ifdef CONFIG_PCI_MSI /* Some chipsets do not support MSI. We cannot easily rely on setting |