| Message ID | 1455630825-27253-5-git-send-email-tn@semihalf.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Feb 16, 2016 at 02:53:34PM +0100, Tomasz Nowicki wrote: > There are two ways we can get ECAM (aka MCFG) regions using ACPI, > first from MCFG static table and second from _CBA method. We cannot remove > static regions, however regions coming from _CBA should be removed while > removing bridge device. > > In the light of above we need flag to mark hot added ECAM entries > and user to call pci_mmconfig_insert while adding regions from _CBA method. > Similarly pci_mmconfig_delete while removing hot added regions. "According to the PCI firmware specification, ACPI provides two standard mechanisms to retrieve ECAM memory mapped configuration regions (aka MCFG). For non-hot-removable bridges, ECAM bridge configurations are retrieved from the static MCFG table and have to be considered non-hot-removable for the current boot; hot-removable PCI host bridges configurations are retrieved through bridges _CBA methods. When ECAM regions are added through _CBA methods, they can be marked as hot-added so that, upon respective PCI host bridge hot-removal, they can be unmapped and deleted in that no longer needed. This patch adds a flag to MCFG regions allowing to mark them as hot-added, so that upon corresponding PCI bridge hot-removal they can be deleted since no longer needed." > Signed-off-by: Tomasz Nowicki <tn@semihalf.com> > Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> > Tested-by: Jeremy Linton <jeremy.linton@arm.com> > Tested-by: Duc Dang <dhdang@apm.com> > Tested-by: Dongdong Liu <liudongdong3@huawei.com> > Tested-by: Hanjun Guo <hanjun.guo@linaro.org> > Tested-by: Graeme Gregory <graeme.gregory@linaro.org> > Tested-by: Sinan Kaya <okaya@codeaurora.org> > --- > drivers/acpi/pci_mcfg.c | 4 +++- > include/linux/pci-acpi.h | 1 + > 2 files changed, 4 insertions(+), 1 deletion(-) It would be great if x86 people can have a look, we no longer associate a MCFG region to a bridge structure, the end result should be equivalent though, so: Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > > diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c > index 0467b00..3282f2a 100644 > --- a/drivers/acpi/pci_mcfg.c > +++ b/drivers/acpi/pci_mcfg.c > @@ -74,6 +74,7 @@ static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start, > new->segment = segment; > new->start_bus = start; > new->end_bus = end; > + new->hot_added = false; > > res = &new->res; > res->start = addr + PCI_MMCFG_BUS_OFFSET(start); > @@ -205,6 +206,7 @@ int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end, > } > rc = pci_mmconfig_map_resource(dev, cfg); > if (!rc) { > + cfg->hot_added = true; > list_add_sorted(cfg); > dev_info(dev, "MMCONFIG at %pR (base %#lx)\n", > &cfg->res, (unsigned long)addr); > @@ -228,7 +230,7 @@ int pci_mmconfig_delete(u16 seg, u8 start, u8 end) > mutex_lock(&pci_mmcfg_lock); > list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) > if (cfg->segment == seg && cfg->start_bus == start && > - cfg->end_bus == end) { > + cfg->end_bus == end && cfg->hot_added) { > list_del_rcu(&cfg->list); > synchronize_rcu(); > pci_mmconfig_unmap_resource(cfg); > diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h > index e9450ef..94d8f38 100644 > --- a/include/linux/pci-acpi.h > +++ b/include/linux/pci-acpi.h > @@ -119,6 +119,7 @@ struct pci_mmcfg_region { > u8 start_bus; > u8 end_bus; > char name[PCI_MMCFG_RESOURCE_NAME_LEN]; > + bool hot_added; > }; > > extern int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end, > -- > 1.9.1 >
diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c index 0467b00..3282f2a 100644 --- a/drivers/acpi/pci_mcfg.c +++ b/drivers/acpi/pci_mcfg.c @@ -74,6 +74,7 @@ static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start, new->segment = segment; new->start_bus = start; new->end_bus = end; + new->hot_added = false; res = &new->res; res->start = addr + PCI_MMCFG_BUS_OFFSET(start); @@ -205,6 +206,7 @@ int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end, } rc = pci_mmconfig_map_resource(dev, cfg); if (!rc) { + cfg->hot_added = true; list_add_sorted(cfg); dev_info(dev, "MMCONFIG at %pR (base %#lx)\n", &cfg->res, (unsigned long)addr); @@ -228,7 +230,7 @@ int pci_mmconfig_delete(u16 seg, u8 start, u8 end) mutex_lock(&pci_mmcfg_lock); list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) if (cfg->segment == seg && cfg->start_bus == start && - cfg->end_bus == end) { + cfg->end_bus == end && cfg->hot_added) { list_del_rcu(&cfg->list); synchronize_rcu(); pci_mmconfig_unmap_resource(cfg); diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h index e9450ef..94d8f38 100644 --- a/include/linux/pci-acpi.h +++ b/include/linux/pci-acpi.h @@ -119,6 +119,7 @@ struct pci_mmcfg_region { u8 start_bus; u8 end_bus; char name[PCI_MMCFG_RESOURCE_NAME_LEN]; + bool hot_added; }; extern int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,