diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-02-11 11:32:38 +1100 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-02-11 16:07:37 +1100 |
| commit | cd15b048445d0a54f7147c35a86c5a16ef231554 (patch) | |
| tree | 80c7e63624143adc5d453106ec13f445438c6135 /arch/powerpc/platforms/powernv/setup.c | |
| parent | ea961a828fe7250e954f086d74d9323c3d44c3e4 (diff) | |
powerpc/powernv: Add iommu DMA bypass support for IODA2
This patch adds the support for to create a direct iommu "bypass"
window on IODA2 bridges (such as Power8) allowing to bypass iommu
page translation completely for 64-bit DMA capable devices, thus
significantly improving DMA performances.
Additionally, this adds a hook to the struct iommu_table so that
the IOMMU API / VFIO can disable the bypass when external ownership
is requested, since in that case, the device will be used by an
environment such as userspace or a KVM guest which must not be
allowed to bypass translations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/platforms/powernv/setup.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/setup.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c index 21166f65c97..110f4fbd319 100644 --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c @@ -27,6 +27,7 @@ #include <linux/interrupt.h> #include <linux/bug.h> #include <linux/cpuidle.h> +#include <linux/pci.h> #include <asm/machdep.h> #include <asm/firmware.h> @@ -141,6 +142,13 @@ static void pnv_progress(char *s, unsigned short hex) { } +static int pnv_dma_set_mask(struct device *dev, u64 dma_mask) +{ + if (dev_is_pci(dev)) + return pnv_pci_dma_set_mask(to_pci_dev(dev), dma_mask); + return __dma_set_mask(dev, dma_mask); +} + static void pnv_shutdown(void) { /* Let the PCI code clear up IODA tables */ @@ -238,6 +246,7 @@ define_machine(powernv) { .machine_shutdown = pnv_shutdown, .power_save = powernv_idle, .calibrate_decr = generic_calibrate_decr, + .dma_set_mask = pnv_dma_set_mask, #ifdef CONFIG_KEXEC .kexec_cpu_down = pnv_kexec_cpu_down, #endif |