diff options
| author | Mark Nelson <markn@au1.ibm.com> | 2008-07-24 04:28:48 (GMT) |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-07-25 05:44:40 (GMT) |
| commit | 7886250e9d71b24d0205ac6798ee855fb3836318 (patch) | |
| tree | f961bc97510d86aa56ab47b6154b2835c59965d8 /arch | |
| parent | d6a61bfc06d6f2248f3e75f208d64e794082013c (diff) | |
| download | linux-7886250e9d71b24d0205ac6798ee855fb3836318.tar.xz | |
powerpc/cell: Fixed IOMMU mapping uses weak ordering for a pcie endpoint
At the moment the fixed mapping is by default strongly ordered (the
iommu_fixed=weak boot option must be used to make the fixed mapping weakly
ordered). If we're on a setup where the southbridge is being used in
endpoint mode (triblade and CAB boards) the default should be a weakly
ordered fixed mapping.
This adds a check so that if a node of type pcie-endpoint can be found in
the device tree the fixed mapping is set to be weak by default (but can be
overridden using iommu_fixed=strong).
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/platforms/cell/iommu.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/cell/iommu.c b/arch/powerpc/platforms/cell/iommu.c index 208005c..031124a 100644 --- a/arch/powerpc/platforms/cell/iommu.c +++ b/arch/powerpc/platforms/cell/iommu.c @@ -1150,12 +1150,23 @@ static int iommu_fixed_disabled; static int __init setup_iommu_fixed(char *str) { + struct device_node *pciep; + if (strcmp(str, "off") == 0) iommu_fixed_disabled = 1; - else if (strcmp(str, "weak") == 0) + /* If we can find a pcie-endpoint in the device tree assume that + * we're on a triblade or a CAB so by default the fixed mapping + * should be set to be weakly ordered; but only if the boot + * option WASN'T set for strong ordering + */ + pciep = of_find_node_by_type(NULL, "pcie-endpoint"); + + if (strcmp(str, "weak") == 0 || (pciep && strcmp(str, "strong") != 0)) iommu_fixed_is_weak = 1; + of_node_put(pciep); + return 1; } __setup("iommu_fixed=", setup_iommu_fixed); |