On Fri, May 06, 2022 at 09:25:40AM -0700, Ravi Pokala wrote: > -----Original Message----- > From: <owner-src-committ...@freebsd.org> on behalf of Ruslan Bukin > <b...@freebsd.org> > Date: 2022-05-06, Friday at 08:51 > To: <src-committ...@freebsd.org>, <dev-commits-src-all@FreeBSD.org>, > <dev-commits-src-m...@freebsd.org> > Subject: git: 0b6bacc7874f - main - Add ofw_bus_iommu_map() that maps PCI > requester ID to an IOMMU specifier based on "iommu-map" DTS property. > > The branch main has been updated by br: > > URL: > https://cgit.FreeBSD.org/src/commit/?id=0b6bacc7874f9c68ad35b06f1a7614171eb9ab10 > > commit 0b6bacc7874f9c68ad35b06f1a7614171eb9ab10 > Author: Ruslan Bukin <b...@freebsd.org> > AuthorDate: 2022-05-06 15:41:11 +0000 > Commit: Ruslan Bukin <b...@freebsd.org> > CommitDate: 2022-05-06 15:48:04 +0000 > > Add ofw_bus_iommu_map() that maps PCI requester ID to an IOMMU > specifier based on "iommu-map" DTS property. > > Sponsored by: UKRI > --- > sys/dev/ofw/ofw_bus_subr.c | 44 > ++++++++++++++++++++++++++++++++++++++++++++ > sys/dev/ofw/ofw_bus_subr.h | 3 ++- > 2 files changed, 46 insertions(+), 1 deletion(-) > > diff --git a/sys/dev/ofw/ofw_bus_subr.c b/sys/dev/ofw/ofw_bus_subr.c > index ea57d1086779..408d554b3c7f 100644 > --- a/sys/dev/ofw/ofw_bus_subr.c > +++ b/sys/dev/ofw/ofw_bus_subr.c > @@ -491,6 +491,50 @@ ofw_bus_msimap(phandle_t node, uint16_t pci_rid, > phandle_t *msi_parent, > return (err); > } > > +int > +ofw_bus_iommu_map(phandle_t node, uint16_t pci_rid, phandle_t > *iommu_parent, > + uint32_t *iommu_rid) > +{ > + pcell_t mask, iommu_base, rid_base, rid_length; > + uint32_t masked_rid; > + pcell_t map[4]; > + ssize_t len; > + int err, i; > + > + len = OF_getproplen(node, "iommu-map"); > + if (len <= 0) > + return (ENOENT); > + if (len > sizeof(map)) > + return (ENOMEM); > + > + len = OF_getencprop(node, "iommu-map", map, 16); > + > + err = ENOENT; > + mask = 0xffffffff; > + OF_getencprop(node, "iommu-map-mask", &mask, sizeof(mask)); > + > + masked_rid = pci_rid & mask; > + for (i = 0; i < len; i += 4) { > + rid_base = map[i + 0]; > + rid_length = map[i + 3]; > > Hi Ruslan, > > I'm confused by this. 'map' is declared as a 4-element array, which means > 'map[i + 0]' and 'map[i + 3]' are both only valid when 'i' is 0. But 'i' is > the loop iterator; doesn't that mean you're accessing outside the array after > the 0th time through the loop? > > Thanks,
Thanks, I'll fix this. I did not want to allocate memory here but it looks like we have to, since there is no limit on amount of entires in "iommu-map" property. > > Ravi (rpokala@) > > + if (masked_rid < rid_base || > + masked_rid >= (rid_base + rid_length)) > + continue; > + > + iommu_base = map[i + 2]; > + > + if (iommu_parent != NULL) > + *iommu_parent = map[i + 1]; > + if (iommu_rid != NULL) > + *iommu_rid = masked_rid - rid_base + iommu_base; > + err = 0; > + break; > + } > + > + return (err); > +} > + > static int > ofw_bus_reg_to_rl_helper(device_t dev, phandle_t node, pcell_t acells, > pcell_t scells, > struct resource_list *rl, const char *reg_source) > diff --git a/sys/dev/ofw/ofw_bus_subr.h b/sys/dev/ofw/ofw_bus_subr.h > index 45709c92c1f7..89f291f92373 100644 > --- a/sys/dev/ofw/ofw_bus_subr.h > +++ b/sys/dev/ofw/ofw_bus_subr.h > @@ -92,8 +92,9 @@ int ofw_bus_lookup_imap(phandle_t, struct > ofw_bus_iinfo *, void *, int, > int ofw_bus_search_intrmap(void *, int, void *, int, void *, int, > void *, > void *, void *, int, phandle_t *); > > -/* Routines for processing msi maps */ > +/* Routines for processing msi and iommu maps. */ > int ofw_bus_msimap(phandle_t, uint16_t, phandle_t *, uint32_t *); > +int ofw_bus_iommu_map(phandle_t, uint16_t, phandle_t *, uint32_t *); > > /* Routines for parsing device-tree data into resource lists. */ > int ofw_bus_reg_to_rl(device_t, phandle_t, pcell_t, pcell_t, > >
