| Message ID | SL2P216MB018739B339B453DE872DB71E80610@SL2P216MB0187.KORP216.PROD.OUTLOOK.COM (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | PCI: Patch series to support Thunderbolt without any BIOS support | expand |
On Tue, Oct 29, 2019 at 03:29:21PM +0000, Nicholas Johnson wrote: > Remove checks for resource size in extend_bridge_window(). This is > necessary to allow the pci_bus_distribute_available_resources() to > function when the kernel parameter pci=hpmemsize=nn[KMG] is used to > allocate resources. Because the kernel parameter sets the size of all > hotplug bridges to be the same, there are problems when nested hotplug > bridges are encountered. Fitting a downstream hotplug bridge with size X > and normal bridges with non-zero size Y into parent hotplug bridge with > size X is impossible, and hence the downstream hotplug bridge needs to > shrink to fit into its parent. > > Add check for if bridge is extended or shrunken and adjust pci_dbg to > reflect this. > > Reset the resource if its new size is zero (if we have run out of a > bridge window resource) to prevent the PCI resource assignment code from > attempting to assign a zero-sized resource. > > Rename extend_bridge_window() to adjust_bridge_window() to reflect the > fact that the window can now shrink. > > Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au> > --- > drivers/pci/setup-bus.c | 23 +++++++++++++++-------- > 1 file changed, 15 insertions(+), 8 deletions(-) > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > index fe8b2c715..f8cd54584 100644 > --- a/drivers/pci/setup-bus.c > +++ b/drivers/pci/setup-bus.c > @@ -1814,7 +1814,7 @@ void __init pci_assign_unassigned_resources(void) > } > } > > -static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, > +static void adjust_bridge_window(struct pci_dev *bridge, struct resource *res, > struct list_head *add_list, > resource_size_t new_size) > { > @@ -1823,13 +1823,20 @@ static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, > if (res->parent) > return; > > - if (resource_size(res) >= new_size) > - return; > + if (new_size > resource_size(res)) { > + add_size = new_size - resource_size(res); > + pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, > + &add_size); > + } else if (new_size < resource_size(res)) { > + add_size = resource_size(res) - new_size; > + pci_dbg(bridge, "bridge window %pR shrunken by %pa\n", res, > + &add_size); > + } Do we need to care about new_size == resource_size(res)? Also there are several calls of resource_size(res) above so probably worth storing it into a helper variable. > - add_size = new_size - resource_size(res); > - pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, &add_size); > res->end = res->start + new_size - 1; > remove_from_list(add_list, res); > + if (!new_size) > + reset_resource(res); > }
On Wed, Oct 30, 2019 at 02:07:05PM +0200, mika.westerberg@linux.intel.com wrote: > On Tue, Oct 29, 2019 at 03:29:21PM +0000, Nicholas Johnson wrote: > > Remove checks for resource size in extend_bridge_window(). This is > > necessary to allow the pci_bus_distribute_available_resources() to > > function when the kernel parameter pci=hpmemsize=nn[KMG] is used to > > allocate resources. Because the kernel parameter sets the size of all > > hotplug bridges to be the same, there are problems when nested hotplug > > bridges are encountered. Fitting a downstream hotplug bridge with size X > > and normal bridges with non-zero size Y into parent hotplug bridge with > > size X is impossible, and hence the downstream hotplug bridge needs to > > shrink to fit into its parent. > > > > Add check for if bridge is extended or shrunken and adjust pci_dbg to > > reflect this. > > > > Reset the resource if its new size is zero (if we have run out of a > > bridge window resource) to prevent the PCI resource assignment code from > > attempting to assign a zero-sized resource. > > > > Rename extend_bridge_window() to adjust_bridge_window() to reflect the > > fact that the window can now shrink. > > > > Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au> > > --- > > drivers/pci/setup-bus.c | 23 +++++++++++++++-------- > > 1 file changed, 15 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > > index fe8b2c715..f8cd54584 100644 > > --- a/drivers/pci/setup-bus.c > > +++ b/drivers/pci/setup-bus.c > > @@ -1814,7 +1814,7 @@ void __init pci_assign_unassigned_resources(void) > > } > > } > > > > -static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, > > +static void adjust_bridge_window(struct pci_dev *bridge, struct resource *res, > > struct list_head *add_list, > > resource_size_t new_size) > > { > > @@ -1823,13 +1823,20 @@ static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, > > if (res->parent) > > return; > > > > - if (resource_size(res) >= new_size) > > - return; > > + if (new_size > resource_size(res)) { > > + add_size = new_size - resource_size(res); > > + pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, > > + &add_size); > > + } else if (new_size < resource_size(res)) { > > + add_size = resource_size(res) - new_size; > > + pci_dbg(bridge, "bridge window %pR shrunken by %pa\n", res, > > + &add_size); > > + } > > Do we need to care about new_size == resource_size(res)? Sorry, I skipped over this before re-posting. If we are not changing the size, does it need to be logged in pci_dbg? I could change it to ">=", meaning if the size does not change then it will be "extended" by 0 in pci_dbg. Let me know if you wish for this to happen. But I am easy either way. If you are fine with how it is, PATCH v10 should have addressed everything so far. > > Also there are several calls of resource_size(res) above so probably > worth storing it into a helper variable. > > > - add_size = new_size - resource_size(res); > > - pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, &add_size); > > res->end = res->start + new_size - 1; > > remove_from_list(add_list, res); > > + if (!new_size) > > + reset_resource(res); > > } Cheers
On Wed, Oct 30, 2019 at 01:22:44PM +0000, Nicholas Johnson wrote: > On Wed, Oct 30, 2019 at 02:07:05PM +0200, mika.westerberg@linux.intel.com wrote: > > On Tue, Oct 29, 2019 at 03:29:21PM +0000, Nicholas Johnson wrote: > > > Remove checks for resource size in extend_bridge_window(). This is > > > necessary to allow the pci_bus_distribute_available_resources() to > > > function when the kernel parameter pci=hpmemsize=nn[KMG] is used to > > > allocate resources. Because the kernel parameter sets the size of all > > > hotplug bridges to be the same, there are problems when nested hotplug > > > bridges are encountered. Fitting a downstream hotplug bridge with size X > > > and normal bridges with non-zero size Y into parent hotplug bridge with > > > size X is impossible, and hence the downstream hotplug bridge needs to > > > shrink to fit into its parent. > > > > > > Add check for if bridge is extended or shrunken and adjust pci_dbg to > > > reflect this. > > > > > > Reset the resource if its new size is zero (if we have run out of a > > > bridge window resource) to prevent the PCI resource assignment code from > > > attempting to assign a zero-sized resource. > > > > > > Rename extend_bridge_window() to adjust_bridge_window() to reflect the > > > fact that the window can now shrink. > > > > > > Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au> > > > --- > > > drivers/pci/setup-bus.c | 23 +++++++++++++++-------- > > > 1 file changed, 15 insertions(+), 8 deletions(-) > > > > > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > > > index fe8b2c715..f8cd54584 100644 > > > --- a/drivers/pci/setup-bus.c > > > +++ b/drivers/pci/setup-bus.c > > > @@ -1814,7 +1814,7 @@ void __init pci_assign_unassigned_resources(void) > > > } > > > } > > > > > > -static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, > > > +static void adjust_bridge_window(struct pci_dev *bridge, struct resource *res, > > > struct list_head *add_list, > > > resource_size_t new_size) > > > { > > > @@ -1823,13 +1823,20 @@ static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, > > > if (res->parent) > > > return; > > > > > > - if (resource_size(res) >= new_size) > > > - return; > > > + if (new_size > resource_size(res)) { > > > + add_size = new_size - resource_size(res); > > > + pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, > > > + &add_size); > > > + } else if (new_size < resource_size(res)) { > > > + add_size = resource_size(res) - new_size; > > > + pci_dbg(bridge, "bridge window %pR shrunken by %pa\n", res, > > > + &add_size); > > > + } > > > > Do we need to care about new_size == resource_size(res)? > Sorry, I skipped over this before re-posting. If we are not changing the > size, does it need to be logged in pci_dbg? I could change it to ">=", > meaning if the size does not change then it will be "extended" by 0 in > pci_dbg. > > Let me know if you wish for this to happen. But I am easy either way. No need. > If you are fine with how it is, PATCH v10 should have addressed > everything so far. Yes, v10 looks fine by me.
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index fe8b2c715..f8cd54584 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1814,7 +1814,7 @@ void __init pci_assign_unassigned_resources(void) } } -static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, +static void adjust_bridge_window(struct pci_dev *bridge, struct resource *res, struct list_head *add_list, resource_size_t new_size) { @@ -1823,13 +1823,20 @@ static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, if (res->parent) return; - if (resource_size(res) >= new_size) - return; + if (new_size > resource_size(res)) { + add_size = new_size - resource_size(res); + pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, + &add_size); + } else if (new_size < resource_size(res)) { + add_size = resource_size(res) - new_size; + pci_dbg(bridge, "bridge window %pR shrunken by %pa\n", res, + &add_size); + } - add_size = new_size - resource_size(res); - pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, &add_size); res->end = res->start + new_size - 1; remove_from_list(add_list, res); + if (!new_size) + reset_resource(res); } static void pci_bus_distribute_available_resources(struct pci_bus *bus, @@ -1865,9 +1872,9 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, * Update the resources to fill as much remaining resource space in the * parent bridge as possible, while considering alignment. */ - extend_bridge_window(bridge, io_res, add_list, resource_size(&io)); - extend_bridge_window(bridge, mmio_res, add_list, resource_size(&mmio)); - extend_bridge_window(bridge, mmio_pref_res, add_list, + adjust_bridge_window(bridge, io_res, add_list, resource_size(&io)); + adjust_bridge_window(bridge, mmio_res, add_list, resource_size(&mmio)); + adjust_bridge_window(bridge, mmio_pref_res, add_list, resource_size(&mmio_pref)); /*
Remove checks for resource size in extend_bridge_window(). This is necessary to allow the pci_bus_distribute_available_resources() to function when the kernel parameter pci=hpmemsize=nn[KMG] is used to allocate resources. Because the kernel parameter sets the size of all hotplug bridges to be the same, there are problems when nested hotplug bridges are encountered. Fitting a downstream hotplug bridge with size X and normal bridges with non-zero size Y into parent hotplug bridge with size X is impossible, and hence the downstream hotplug bridge needs to shrink to fit into its parent. Add check for if bridge is extended or shrunken and adjust pci_dbg to reflect this. Reset the resource if its new size is zero (if we have run out of a bridge window resource) to prevent the PCI resource assignment code from attempting to assign a zero-sized resource. Rename extend_bridge_window() to adjust_bridge_window() to reflect the fact that the window can now shrink. Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au> --- drivers/pci/setup-bus.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-)