Messages in this thread | | | Subject | Re: [PATCH 2/4] powerpc/pseries/iommu: Implement ibm,reset-pe-dma-windows rtas call | From | Alexey Kardashevskiy <> | Date | Mon, 22 Jun 2020 20:02:22 +1000 |
| |
On 19/06/2020 15:06, Leonardo Bras wrote: > Platforms supporting the DDW option starting with LoPAR level 2.7 implement > ibm,ddw-extensions. The first extension available (index 2) carries the > token for ibm,reset-pe-dma-windows rtas call, which is used to restore > the default DMA window for a device, if it has been deleted. > > It does so by resetting the TCE table allocation for the PE to it's > boot time value, available in "ibm,dma-window" device tree node. > > Signed-off-by: Leonardo Bras <leobras.c@gmail.com> > --- > arch/powerpc/platforms/pseries/iommu.c | 33 ++++++++++++++++++++++++++ > 1 file changed, 33 insertions(+) > > diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c > index e5a617738c8b..5e1fbc176a37 100644 > --- a/arch/powerpc/platforms/pseries/iommu.c > +++ b/arch/powerpc/platforms/pseries/iommu.c > @@ -1012,6 +1012,39 @@ static phys_addr_t ddw_memory_hotplug_max(void) > return max_addr; > } > > +/* > + * Platforms supporting the DDW option starting with LoPAR level 2.7 implement > + * ibm,ddw-extensions, which carries the rtas token for > + * ibm,reset-pe-dma-windows. > + * That rtas-call can be used to restore the default DMA window for the device. > + */ > +static void reset_dma_window(struct pci_dev *dev, struct device_node *par_dn) > +{ > + int ret; > + u32 cfg_addr, ddw_ext[3]; > + u64 buid; > + struct device_node *dn; > + struct pci_dn *pdn; > + > + ret = of_property_read_u32_array(par_dn, "ibm,ddw-extensions", > + &ddw_ext[0], 3);
s/3/2/ as for the reset extension you do not need the "64bit largest block" extension.
> + if (ret) > + return; > + > + dn = pci_device_to_OF_node(dev); > + pdn = PCI_DN(dn); > + buid = pdn->phb->buid; > + cfg_addr = ((pdn->busno << 16) | (pdn->devfn << 8)); > + > + ret = rtas_call(ddw_ext[1], 3, 1, NULL, cfg_addr,
Here the "reset" extention is in ddw_ext[1]. Hm. 1/4 has a bug then.
And I am pretty sure it won't compile as reset_dma_window() is not used and it is static so fold it into one the next patches. Thanks,
> + BUID_HI(buid), BUID_LO(buid)); > + if (ret) > + dev_info(&dev->dev, > + "ibm,reset-pe-dma-windows(%x) %x %x %x returned %d ", > + ddw_ext[1], cfg_addr, BUID_HI(buid), BUID_LO(buid), > + ret); > +} > + > /* > * If the PE supports dynamic dma windows, and there is space for a table > * that can map all pages in a linear offset, then setup such a table, >
-- Alexey
| |