From mboxrd@z Thu Jan 1 00:00:00 1970 From: msalter@redhat.com (Mark Salter) Date: Thu, 14 Jan 2016 10:36:16 -0500 Subject: [PATCH V3 20/21] pci, acpi: Match PCI config space accessors against platfrom specific quirks. In-Reply-To: <1452691267-32240-21-git-send-email-tn@semihalf.com> References: <1452691267-32240-1-git-send-email-tn@semihalf.com> <1452691267-32240-21-git-send-email-tn@semihalf.com> Message-ID: <1452785776.28109.22.camel@redhat.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, 2016-01-13 at 14:21 +0100, Tomasz Nowicki wrote: > Some platforms may not be fully compliant with generic set of PCI config > accessors. For these cases we implement the way to overwrite accessors > set prior to PCI buses enumeration. Algorithm traverses available quirk > list, matches against tuple and > returns corresponding accessors. All quirks can be defined using: > DECLARE_ACPI_MCFG_FIXUP() and keep self contained. Example, > > static const struct dmi_system_id foo_dmi[] = { > ????????{ > ????????????????.ident = "", > ????????????????.callback = , > ????????????????.matches = { > ????????????????????????DMI_MATCH(DMI_SYS_VENDOR, ""), > ????????????????????????DMI_MATCH(DMI_PRODUCT_NAME, ""), > ????????????????????????DMI_MATCH(DMI_PRODUCT_VERSION, "product version"), > ????????????????}, > ????????}, > ????????{ } > }; > > static struct pci_ops foo_ecam_pci_ops = { > ????????.map_bus = pci_mcfg_dev_base, > ????????.read = foo_ecam_config_read, > ????????.write = foo_ecam_config_write, > }; > DECLARE_ACPI_MCFG_FIXUP(foo_dmi, NULL, &foo_ecam_pci_ops, , ); > > More custom (non-DMI) matching can be done via an alternative call. > Note that there is possibility to assign quirk related private data to > root->sysdata which will be available along read/wriate accessor, example: > > static int boo_match(struct pci_mcfg_fixup *fixup, struct acpi_pci_root *root) > { > ????????return [condition] ? 1 : 0; > } > > int boo_ecam_config_read(struct pci_bus *bus, unsigned int devfn, > ??????????????????????????int where, int size, u32 *val) > { > ????????struct acpi_pci_root *root = bus->sysdata; > ????????struct boo_priv_data *boo_data = root->sysdata; > > ????????[..] > } > > static struct pci_ops boo_ecam_pci_ops = { > .map_bus = pci_mcfg_dev_base, > .read = boo_ecam_config_read, > .write = boo_ecam_config_write, > }; > DECLARE_ACPI_MCFG_FIXUP(NULL, boo_match, &boo_ecam_pci_ops, , ); > > Signed-off-by: Tomasz Nowicki > --- > ?drivers/acpi/mcfg.c???????????????| 33 +++++++++++++++++++++++++++++++-- > ?include/acpi/acpi_bus.h???????????|??1 + > ?include/asm-generic/vmlinux.lds.h |??7 +++++++ > ?include/linux/ecam.h??????????????| 18 ++++++++++++++++++ > ?4 files changed, 57 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/mcfg.c b/drivers/acpi/mcfg.c > index dfc2d14..ec5fe7b 100644 > --- a/drivers/acpi/mcfg.c > +++ b/drivers/acpi/mcfg.c > @@ -8,6 +8,7 @@ > ? */ > ? > ?#include > +#include > ?#include > ?#include > ?#include > @@ -34,6 +35,29 @@ int __weak raw_pci_write(unsigned int domain, unsigned int bus, > ? return PCIBIOS_DEVICE_NOT_FOUND; > ?} > ? > +extern struct pci_mcfg_fixup __start_acpi_mcfg_fixups[]; > +extern struct pci_mcfg_fixup __end_acpi_mcfg_fixups[]; > + > +static struct pci_ops *pci_mcfg_check_quirks(struct acpi_pci_root *root) > +{ > + struct pci_mcfg_fixup *f; > + int bus_num = root->secondary.start; > + int domain = root->segment; > + > + /* > + ?* First match against PCI topology then use DMI or > + ?* custom match handler. > + ?*/ > + for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups; f++) { > + if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) && > + ????(f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) && > + ????(f->system ? dmi_check_system(f->system) : 0 || > + ?????f->match ? f->match(f, root) : 0)) > + return f->ops; I think this would be better as: ????(f->system ? dmi_check_system(f->system) : 1 && ?????f->match ? f->match(f, root) : 1)) return f->ops; Otherwise, one has to call dmi_check_system() from f->match() if access to root is needed. ?? > + } > + return NULL; > +} > + > ?void __iomem * > ?pci_mcfg_dev_base(struct pci_bus *bus, unsigned int devfn, int offset) > ?{ > @@ -56,10 +80,15 @@ static struct pci_ops default_pci_mcfg_ops = { > ? > ?struct pci_ops *pci_mcfg_get_ops(struct acpi_pci_root *root) > ?{ > + struct pci_ops *pci_mcfg_ops_quirk; > + > ? /* > - ?* TODO: Match against platform specific quirks and return > - ?* corresponding PCI config space accessor set. > + ?* Match against platform specific quirks and return corresponding > + ?* PCI config space accessor set. > ? ?*/ > + pci_mcfg_ops_quirk = pci_mcfg_check_quirks(root); > + if (pci_mcfg_ops_quirk) > + return pci_mcfg_ops_quirk; > ? > ? return &default_pci_mcfg_ops; > ?} > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h > index ad0a5ff..ea4d2b5 100644 > --- a/include/acpi/acpi_bus.h > +++ b/include/acpi/acpi_bus.h > @@ -554,6 +554,7 @@ struct acpi_pci_root { > ? struct pci_bus *bus; > ? u16 segment; > ? struct resource secondary; /* downstream bus range */ > + void *sysdata; > ? > ? u32 osc_support_set; /* _OSC state of support bits */ > ? u32 osc_control_set; /* _OSC state of control bits */ > diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h > index c4bd0e2..c93fc97 100644 > --- a/include/asm-generic/vmlinux.lds.h > +++ b/include/asm-generic/vmlinux.lds.h > @@ -298,6 +298,13 @@ > ? VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .; \ > ? } \ > ? \ > + /* ACPI MCFG quirks */ \ > + .acpi_fixup????????: AT(ADDR(.acpi_fixup) - LOAD_OFFSET) { \ > + VMLINUX_SYMBOL(__start_acpi_mcfg_fixups) = .; \ > + *(.acpi_fixup_mcfg) \ > + VMLINUX_SYMBOL(__end_acpi_mcfg_fixups) = .; \ > + } \ > + \ > ? /* Built-in firmware blobs */ \ > ? .builtin_fw????????: AT(ADDR(.builtin_fw) - LOAD_OFFSET) { \ > ? VMLINUX_SYMBOL(__start_builtin_fw) = .; \ > diff --git a/include/linux/ecam.h b/include/linux/ecam.h > index e0f322e..21215be 100644 > --- a/include/linux/ecam.h > +++ b/include/linux/ecam.h > @@ -20,6 +20,24 @@ struct pci_mmcfg_region { > ? bool hot_added; > ?}; > ? > +struct pci_mcfg_fixup { > + const struct dmi_system_id *system; > + int (*match)(struct pci_mcfg_fixup *, struct acpi_pci_root *); > + struct pci_ops *ops; > + int domain; > + int bus_num; > +}; > + > +#define PCI_MCFG_DOMAIN_ANY -1 > +#define PCI_MCFG_BUS_ANY -1 > + > +/* Designate a routine to fix up buggy MCFG */ > +#define DECLARE_ACPI_MCFG_FIXUP(system, match, ops, dom, bus) \ > + static const struct pci_mcfg_fixup __mcfg_fixup_##system##dom##bus\ > + ?__used __attribute__((__section__(".acpi_fixup_mcfg"), \ > + aligned((sizeof(void *))))) = \ > + { system, match, ops, dom, bus }; > + > ?struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus); > ?struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start, > ? ???int end, u64 addr);