On Tue, Feb 16, 2016 at 02:53:31PM +0100, Tomasz Nowicki wrote: > From: Jayachandran C <[email protected]> > > Move pci_mmcfg_list handling to a drivers/acpi/pci_mcfg.c. This is > to share the API and code with ARM64 later. The corresponding > declarations are moved from asm/pci_x86.h to linux/pci-acpi.h > > As a part of this we introduce three functions that can be > implemented by the arch code: pci_mmconfig_map_resource() to map a > mcfg entry, pci_mmconfig_unmap_resource to do the corresponding > unmap and pci_mmconfig_enabled to see if the arch setup of > mcfg entries was successful. We also provide weak implementations > of these, which will be used from ARM64. On x86, we retain the > old logic by providing platform specific implementation. > > This patch is purely rearranging code, it should not have any > impact on the logic of MCFG parsing or list handling. > > Signed-off-by: Jayachandran C <[email protected]> > [Xen parts:] > Acked-by: David Vrabel <[email protected]> > --- > arch/x86/include/asm/pci_x86.h | 24 +--- > arch/x86/pci/mmconfig-shared.c | 269 +++++------------------------------ > arch/x86/pci/mmconfig_32.c | 1 + > arch/x86/pci/mmconfig_64.c | 1 + > arch/x86/pci/numachip.c | 1 + > drivers/acpi/Makefile | 1 + > drivers/acpi/pci_mcfg.c | 312 > +++++++++++++++++++++++++++++++++++++++++ > drivers/xen/pci.c | 5 +- > include/linux/pci-acpi.h | 33 +++++ > 9 files changed, 386 insertions(+), 261 deletions(-) > create mode 100644 drivers/acpi/pci_mcfg.c
This patch makes perfect sense to me and manages to move MCFG handling to common code in a seamless manner, it is basically a code move with weak functions to cater for X86 specific legacy bits which are otherwise pretty complex to untangle, so (apart from a few nits below): Reviewed-by: Lorenzo Pieralisi <[email protected]> [...] > diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c > new file mode 100644 > index 0000000..ea84365 > --- /dev/null > +++ b/drivers/acpi/pci_mcfg.c > @@ -0,0 +1,312 @@ > +/* > + * pci_mcfg.c > + * > + * Common code to maintain the MCFG areas and mappings > + * > + * This has been extracted from arch/x86/pci/mmconfig-shared.c > + * and moved here so that other architectures can use this code. > + */ > + > +#include <linux/pci.h> > +#include <linux/init.h> > +#include <linux/dmi.h> > +#include <linux/pci-acpi.h> > +#include <linux/sfi_acpi.h> > +#include <linux/slab.h> > +#include <linux/mutex.h> > +#include <linux/rculist.h> Nit: while at it order them alphabetically. > + > +#define PREFIX "ACPI: " > + > +static DEFINE_MUTEX(pci_mmcfg_lock); > +LIST_HEAD(pci_mmcfg_list); > + > +static void list_add_sorted(struct pci_mmcfg_region *new) > +{ > + struct pci_mmcfg_region *cfg; > + > + /* keep list sorted by segment and starting bus number */ > + list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) { > + if (cfg->segment > new->segment || > + (cfg->segment == new->segment && > + cfg->start_bus >= new->start_bus)) { > + list_add_tail_rcu(&new->list, &cfg->list); > + return; > + } > + } > + list_add_tail_rcu(&new->list, &pci_mmcfg_list); > +} > + > +static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start, > + int end, u64 addr) > +{ > + struct pci_mmcfg_region *new; > + struct resource *res; > + > + if (addr == 0) > + return NULL; > + > + new = kzalloc(sizeof(*new), GFP_KERNEL); > + if (!new) > + return NULL; > + > + new->address = addr; > + new->segment = segment; > + new->start_bus = start; > + new->end_bus = end; > + > + res = &new->res; > + res->start = addr + PCI_MMCFG_BUS_OFFSET(start); > + res->end = addr + PCI_MMCFG_BUS_OFFSET(end + 1) - 1; > + res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; > + snprintf(new->name, PCI_MMCFG_RESOURCE_NAME_LEN, > + "PCI MMCONFIG %04x [bus %02x-%02x]", segment, start, end); > + res->name = new->name; > + > + return new; > +} > + > +struct pci_mmcfg_region *pci_mmconfig_add(int segment, int start, > + int end, u64 addr) > +{ > + struct pci_mmcfg_region *new; > + > + new = pci_mmconfig_alloc(segment, start, end, addr); > + if (new) { > + mutex_lock(&pci_mmcfg_lock); > + list_add_sorted(new); > + mutex_unlock(&pci_mmcfg_lock); > + > + pr_info(PREFIX > + "MMCONFIG for domain %04x [bus %02x-%02x] at %pR " > + "(base %#lx)\n", > + segment, start, end, &new->res, (unsigned long)addr); > + } > + > + return new; > +} > + > +struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus) > +{ > + struct pci_mmcfg_region *cfg; > + > + list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) > + if (cfg->segment == segment && > + cfg->start_bus <= bus && bus <= cfg->end_bus) > + return cfg; > + > + return NULL; > +} > + > +/* > + * Map a pci_mmcfg_region, can be overrriden by arch s/overrriden/overridden/ [...] > +static int __init acpi_mcfg_check_entry(struct acpi_table_mcfg *mcfg, > + struct acpi_mcfg_allocation *cfg) > +{ > + int year; > + > + if (!config_enabled(CONFIG_X86)) > + return 0; This check in generic code may ruffle someone's feathers, I even think we can run this function safely on ARM64 but to prevent surprises we'd better keep the X86 check, alternatives like adding a weak function just for a quirk do not make much sense to me. Lorenzo > + > + if (cfg->address < 0xFFFFFFFF) > + return 0; > + > + if (!strncmp(mcfg->header.oem_id, "SGI", 3)) > + return 0; > + > + if (mcfg->header.revision >= 1) { > + if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && > + year >= 2010) > + return 0; > + } > + > + pr_err(PREFIX "MCFG region for %04x [bus %02x-%02x] at %#llx " > + "is above 4GB, ignored\n", cfg->pci_segment, > + cfg->start_bus_number, cfg->end_bus_number, cfg->address); > + return -EINVAL; > +} > + > +static int __init pci_parse_mcfg(struct acpi_table_header *header) > +{ > + struct acpi_table_mcfg *mcfg; > + struct acpi_mcfg_allocation *cfg_table, *cfg; > + unsigned long i; > + int entries; > + > + if (!header) > + return -EINVAL; > + > + mcfg = (struct acpi_table_mcfg *)header; > + > + /* how many config structures do we have */ > + entries = 0; > + i = header->length - sizeof(struct acpi_table_mcfg); > + while (i >= sizeof(struct acpi_mcfg_allocation)) { > + entries++; > + i -= sizeof(struct acpi_mcfg_allocation); > + } > + if (entries == 0) { > + pr_err(PREFIX "MMCONFIG has no entries\n"); > + return -ENODEV; > + } > + > + cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1]; > + for (i = 0; i < entries; i++) { > + cfg = &cfg_table[i]; > + if (acpi_mcfg_check_entry(mcfg, cfg)) > + return -ENODEV; > + > + if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number, > + cfg->end_bus_number, cfg->address) == NULL) { > + pr_warn(PREFIX "no memory for MCFG entries\n"); > + return -ENOMEM; > + } > + } > + > + return 0; > +} > + > +int __init pci_mmconfig_parse_table(void) > +{ > + return acpi_sfi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg); > +} > + > +void __weak __init pci_mmcfg_late_init(void) > +{ > + int err, n = 0; > + struct pci_mmcfg_region *cfg; > + > + err = pci_mmconfig_parse_table(); > + if (err) { > + pr_err(PREFIX " Failed to parse MCFG (%d)\n", err); > + return; > + } > + > + list_for_each_entry(cfg, &pci_mmcfg_list, list) { > + pci_mmconfig_map_resource(NULL, cfg); > + n++; > + } > + > + pr_info(PREFIX " MCFG table loaded %d entries\n", n); > +} > diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c > index 7494dbe..97aa9d3 100644 > --- a/drivers/xen/pci.c > +++ b/drivers/xen/pci.c > @@ -27,9 +27,6 @@ > #include <asm/xen/hypervisor.h> > #include <asm/xen/hypercall.h> > #include "../pci/pci.h" > -#ifdef CONFIG_PCI_MMCONFIG > -#include <asm/pci_x86.h> > -#endif > > static bool __read_mostly pci_seg_supported = true; > > @@ -221,7 +218,7 @@ static int __init xen_mcfg_late(void) > if (!xen_initial_domain()) > return 0; > > - if ((pci_probe & PCI_PROBE_MMCONF) == 0) > + if (!pci_mmconfig_enabled()) > return 0; > > if (list_empty(&pci_mmcfg_list)) > diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h > index 89ab057..e9450ef 100644 > --- a/include/linux/pci-acpi.h > +++ b/include/linux/pci-acpi.h > @@ -106,6 +106,39 @@ extern const u8 pci_acpi_dsm_uuid[]; > #define RESET_DELAY_DSM 0x08 > #define FUNCTION_DELAY_DSM 0x09 > > +/* common API to maintain list of MCFG regions */ > +/* "PCI MMCONFIG %04x [bus %02x-%02x]" */ > +#define PCI_MMCFG_RESOURCE_NAME_LEN (22 + 4 + 2 + 2) > + > +struct pci_mmcfg_region { > + struct list_head list; > + struct resource res; > + u64 address; > + char __iomem *virt; > + u16 segment; > + u8 start_bus; > + u8 end_bus; > + char name[PCI_MMCFG_RESOURCE_NAME_LEN]; > +}; > + > +extern int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end, > + phys_addr_t addr); > +extern int pci_mmconfig_delete(u16 seg, u8 start, u8 end); > + > +extern struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus); > +extern struct pci_mmcfg_region *pci_mmconfig_add(int segment, int start, > + int end, u64 addr); > +extern int pci_mmconfig_map_resource(struct device *dev, > + struct pci_mmcfg_region *mcfg); > +extern void pci_mmconfig_unmap_resource(struct pci_mmcfg_region *mcfg); > +extern int pci_mmconfig_enabled(void); > +extern int __init pci_mmconfig_parse_table(void); > + > +extern struct list_head pci_mmcfg_list; > + > +#define PCI_MMCFG_BUS_OFFSET(bus) ((bus) << 20) > +#define PCI_MMCFG_OFFSET(bus, devfn) ((bus) << 20 | (devfn) << 12) > + > #else /* CONFIG_ACPI */ > static inline void acpi_pci_add_bus(struct pci_bus *bus) { } > static inline void acpi_pci_remove_bus(struct pci_bus *bus) { } > -- > 1.9.1 >
