[RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space accessors against platfrom specific ECAM quirks
From: Christopher Covington <hidden>
Date: 2016-06-13 15:47:24
Also in:
linux-acpi, linux-pci, lkml
Hi Dongdong, On 06/13/2016 09:02 AM, Dongdong Liu wrote:
quoted hunk ↗ jump to hunk
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)))
This would just be a small convenience, but if the character count used here were min(strlen(f->oem_id), ACPI_OEM_ID_SIZE) then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings and wouldn't need to be padded out to the full length.
+ return f->ops; + } + /* No quirks, use ECAM */ + return &pci_generic_ecam_ops; +}
quoted hunk ↗ jump to hunk
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 \
I'm not entirely sure that this is the right fix--I'm pretty blindly
following a GCC documentation suggestion [1]--but removing the first two
preprocessor concatenation operators "##" solved the following build error
for me.
include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and ""QCOM"" does not give a valid preprocessing token
__mcfg_fixup_##oem_id##oem_table_id##dom##bus \
^
arch/arm64/kernel/pci.c:225:1: note: in expansion of macro ?DECLARE_ACPI_MCFG_FIXUP?
DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
^
arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432"" does not give a valid preprocessing token
DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
^
include/linux/pci-acpi.h:90:17: note: in definition of macro ?DECLARE_ACPI_MCFG_FIXUP?
__mcfg_fixup_##oem_id##oem_table_id##dom##bus \
^
arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi
ng token
DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
^
include/linux/pci-acpi.h:90:25: note: in definition of macro ?DECLARE_ACPI_MCFG_FIXUP?
__mcfg_fixup_##oem_id##oem_table_id##dom##bus \
^
arch/arm64/kernel/pci.c:225:44: error: expected ?=?, ?,?, ?;?, ?asm? or ?__attribute__? before string constant
DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
^
include/linux/pci-acpi.h:90:17: note: in definition of macro ?DECLARE_ACPI_MCFG_FIXUP?
__mcfg_fixup_##oem_id##oem_table_id##dom##bus \
^
make[1]: *** [arch/arm64/kernel/pci.o] Error 1
make: *** [arch/arm64/kernel] Error 2
1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation
+ __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,Thanks, Cov -- Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project