Hi Tomasz, Jon > -----Original Message----- > From: liudongdong (C) > Sent: 13 June 2016 14:02 > To: helgaas@xxxxxxxxxx; arnd@xxxxxxxx; will.deacon@xxxxxxx; > catalin.marinas@xxxxxxx; rafael@xxxxxxxxxx; hanjun.guo@xxxxxxxxxx; > Lorenzo.Pieralisi@xxxxxxx; okaya@xxxxxxxxxxxxxx; jchandra@xxxxxxxxxxxx; > tn@xxxxxxxxxxxx > Cc: robert.richter@xxxxxxxxxxxxxxxxxx; mw@xxxxxxxxxxxx; > Liviu.Dudau@xxxxxxx; ddaney@xxxxxxxxxxxxxxxxxx; Wangyijing; > Suravee.Suthikulpanit@xxxxxxx; msalter@xxxxxxxxxx; linux- > pci@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux- > acpi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linaro- > acpi@xxxxxxxxxxxxxxxx; jcm@xxxxxxxxxx; andrea.gallo@xxxxxxxxxx; > dhdang@xxxxxxx; jeremy.linton@xxxxxxx; liudongdong (C); > cov@xxxxxxxxxxxxxx; Gabriele Paoloni; Chenxin (Charles); Linuxarm > Subject: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space accessors > against platfrom specific ECAM quirks > > From: Tomasz Nowicki <tn@xxxxxxxxxxxx> > > 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. Algorithm traverses available quirk list, matches against > <oem_id, oem_table_id, domain, bus number> tuple and returns > corresponding > PCI config ops. oem_id and oem_table_id come from MCFG table standard > header. > All quirks can be defined using DECLARE_ACPI_MCFG_FIXUP() macro and > kept self contained. Example: > > /* Custom PCI config ops */ > static struct pci_generic_ecam_ops foo_pci_ops = { > .bus_shift = 24, > .pci_ops = { > .map_bus = pci_ecam_map_bus, > .read = foo_ecam_config_read, > .write = foo_ecam_config_write, > } > }; > > DECLARE_ACPI_MCFG_FIXUP(&foo_pci_ops, <oem_id_str>, <oem_table_id>, > <domain_nr>, <bus_nr>); > > Signed-off-by: Tomasz Nowicki <tn@xxxxxxxxxxxx> > Signed-off-by: Dongdong Liu <liudongdong3@xxxxxxxxxx> > --- > drivers/acpi/pci_mcfg.c | 41 > ++++++++++++++++++++++++++++++++++++--- > include/asm-generic/vmlinux.lds.h | 7 +++++++ > include/linux/pci-acpi.h | 20 +++++++++++++++++++ > 3 files changed, 65 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c > index d3c3e85..49612b3 100644 > --- a/drivers/acpi/pci_mcfg.c > +++ b/drivers/acpi/pci_mcfg.c > @@ -22,6 +22,10 @@ > #include <linux/kernel.h> > #include <linux/pci.h> > #include <linux/pci-acpi.h> > +#include <linux/pci-ecam.h> > + > +/* Root pointer to the mapped MCFG table */ > +static struct acpi_table_mcfg *mcfg_table; > > /* Structure to hold entries from the MCFG table */ > struct mcfg_entry { > @@ -35,6 +39,38 @@ struct mcfg_entry { > /* List to save mcfg entries */ > static LIST_HEAD(pci_mcfg_list); > > +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[]; > +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[]; > + > +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root) > +{ > + int bus_num = root->secondary.start; > + int domain = root->segment; > + struct pci_cfg_fixup *f; > + > + if (!mcfg_table) > + return &pci_generic_ecam_ops; > + > + /* > + * Match against platform specific quirks and return > corresponding > + * CAM ops. > + * > + * First match against PCI topology <domain:bus> then use OEM ID > and > + * OEM revision from MCFG table standard header. > + */ > + 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) && > + (!strncmp(f->oem_id, mcfg_table->header.oem_id, > + ACPI_OEM_ID_SIZE)) && > + (!strncmp(f->oem_table_id, mcfg_table- > >header.oem_table_id, > + ACPI_OEM_TABLE_ID_SIZE))) As you can see here Liudongdong has replaced oem_revision with oem_table_id. Now it seems that there are some platforms that have already shipped using a matching based on the oem_revision (right Jon?) However I guess that if in FW they have defined oem_table_id properly they should be able to use this mechanism without needing to a FW update. Can these vendors confirm this? Tomasz do you think this can work for Cavium Thunder? Thanks Gab > + return f->ops; > + } > + /* No quirks, use ECAM */ > + return &pci_generic_ecam_ops; > +} > + > phys_addr_t pci_mcfg_lookup(u16 seg, struct resource *bus_res) > { > struct mcfg_entry *e; > @@ -54,7 +90,6 @@ phys_addr_t pci_mcfg_lookup(u16 seg, struct resource > *bus_res) > > static __init int pci_mcfg_parse(struct acpi_table_header *header) > { > - struct acpi_table_mcfg *mcfg; > struct acpi_mcfg_allocation *mptr; > struct mcfg_entry *e, *arr; > int i, n; > @@ -64,8 +99,8 @@ static __init int pci_mcfg_parse(struct > acpi_table_header *header) > > n = (header->length - sizeof(struct acpi_table_mcfg)) / > sizeof(struct acpi_mcfg_allocation); > - mcfg = (struct acpi_table_mcfg *)header; > - mptr = (struct acpi_mcfg_allocation *) &mcfg[1]; > + mcfg_table = (struct acpi_table_mcfg *)header; > + mptr = (struct acpi_mcfg_allocation *) &mcfg_table[1]; > > arr = kcalloc(n, sizeof(*arr), GFP_KERNEL); > if (!arr) > diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm- > generic/vmlinux.lds.h > index 6a67ab9..43604fc 100644 > --- a/include/asm-generic/vmlinux.lds.h > +++ b/include/asm-generic/vmlinux.lds.h > @@ -300,6 +300,13 @@ > 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/pci-acpi.h b/include/linux/pci-acpi.h > index 7d63a66..088a1da 100644 > --- a/include/linux/pci-acpi.h > +++ b/include/linux/pci-acpi.h > @@ -25,6 +25,7 @@ static inline acpi_status > pci_acpi_remove_pm_notifier(struct acpi_device *dev) > extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle); > > extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource > *bus_res); > +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root > *root); > > static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev > *pdev) > { > @@ -72,6 +73,25 @@ struct acpi_pci_root_ops { > int (*prepare_resources)(struct acpi_pci_root_info *info); > }; > > +struct pci_cfg_fixup { > + struct pci_ecam_ops *ops; > + char *oem_id; > + char *oem_table_id; > + 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(ops, oem_id, oem_table_id, dom, bus) > \ > + static const struct pci_cfg_fixup \ > + __mcfg_fixup_##oem_id##oem_table_id##dom##bus \ > + __used __attribute__((__section__(".acpi_fixup_mcfg"), > \ > + aligned((sizeof(void *))))) = \ > + { ops, oem_id, oem_table_id, dom, bus }; > + > extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info > *info); > extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, > struct acpi_pci_root_ops *ops, > -- > 1.9.1 ?韬{.n?????%??檩??w?{.n???{炳???骅w*jg????????G??⒏⒎?:+v????????????"??????