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author | Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au> | 2019-05-07 14:51:24 -0500 |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2019-05-07 15:53:08 -0500 |
commit | 0d6076184aecb97cc583bc7f9e125518d6c24404 (patch) | |
tree | bf8862b9b703c75613a5554c90a39eab15ae00ba | |
parent | 113fb03ed1d4c1877cc8817e500867616b222380 (diff) | |
download | linux-0d6076184aecb97cc583bc7f9e125518d6c24404.tar.gz linux-0d6076184aecb97cc583bc7f9e125518d6c24404.tar.bz2 linux-0d6076184aecb97cc583bc7f9e125518d6c24404.zip |
PCI: Cleanup setup-bus.c comments and whitespace
Cleanup comments, kernel-doc, coding style. No functional changes
intended; comment and whitespace changes only.
Link: https://lore.kernel.org/lkml/PS2P216MB06427E290A68CDB921FB4B2980250@PS2P216MB0642.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
[bhelgaas: tidy related things throughout the file]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
-rw-r--r-- | drivers/pci/setup-bus.c | 496 |
1 files changed, 249 insertions, 247 deletions
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index ec44a0f3a7ac..6728144308c0 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -49,17 +49,15 @@ static void free_list(struct list_head *head) } /** - * add_to_list() - add a new resource tracker to the list + * add_to_list() - Add a new resource tracker to the list * @head: Head of the list - * @dev: device corresponding to which the resource - * belongs - * @res: The resource to be tracked - * @add_size: additional size to be optionally added - * to the resource + * @dev: Device to which the resource belongs + * @res: Resource to be tracked + * @add_size: Additional size to be optionally added to the resource */ -static int add_to_list(struct list_head *head, - struct pci_dev *dev, struct resource *res, - resource_size_t add_size, resource_size_t min_align) +static int add_to_list(struct list_head *head, struct pci_dev *dev, + struct resource *res, resource_size_t add_size, + resource_size_t min_align) { struct pci_dev_resource *tmp; @@ -80,8 +78,7 @@ static int add_to_list(struct list_head *head, return 0; } -static void remove_from_list(struct list_head *head, - struct resource *res) +static void remove_from_list(struct list_head *head, struct resource *res) { struct pci_dev_resource *dev_res, *tmp; @@ -158,7 +155,7 @@ static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head) tmp->res = r; tmp->dev = dev; - /* fallback is smallest one or list is empty*/ + /* Fallback is smallest one or list is empty */ n = head; list_for_each_entry(dev_res, head, list) { resource_size_t align; @@ -171,21 +168,20 @@ static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head) break; } } - /* Insert it just before n*/ + /* Insert it just before n */ list_add_tail(&tmp->list, n); } } -static void __dev_sort_resources(struct pci_dev *dev, - struct list_head *head) +static void __dev_sort_resources(struct pci_dev *dev, struct list_head *head) { u16 class = dev->class >> 8; - /* Don't touch classless devices or host bridges or ioapics. */ + /* Don't touch classless devices or host bridges or IOAPICs */ if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST) return; - /* Don't touch ioapic devices already enabled by firmware */ + /* Don't touch IOAPIC devices already enabled by firmware */ if (class == PCI_CLASS_SYSTEM_PIC) { u16 command; pci_read_config_word(dev, PCI_COMMAND, &command); @@ -204,19 +200,18 @@ static inline void reset_resource(struct resource *res) } /** - * reassign_resources_sorted() - satisfy any additional resource requests + * reassign_resources_sorted() - Satisfy any additional resource requests * - * @realloc_head : head of the list tracking requests requiring additional - * resources - * @head : head of the list tracking requests with allocated - * resources + * @realloc_head: Head of the list tracking requests requiring + * additional resources + * @head: Head of the list tracking requests with allocated + * resources * - * Walk through each element of the realloc_head and try to procure - * additional resources for the element, provided the element - * is in the head list. + * Walk through each element of the realloc_head and try to procure additional + * resources for the element, provided the element is in the head list. */ static void reassign_resources_sorted(struct list_head *realloc_head, - struct list_head *head) + struct list_head *head) { struct resource *res; struct pci_dev_resource *add_res, *tmp; @@ -228,18 +223,18 @@ static void reassign_resources_sorted(struct list_head *realloc_head, bool found_match = false; res = add_res->res; - /* skip resource that has been reset */ + /* Skip resource that has been reset */ if (!res->flags) goto out; - /* skip this resource if not found in head list */ + /* Skip this resource if not found in head list */ list_for_each_entry(dev_res, head, list) { if (dev_res->res == res) { found_match = true; break; } } - if (!found_match)/* just skip */ + if (!found_match) /* Just skip */ continue; idx = res - &add_res->dev->resource[0]; @@ -267,14 +262,14 @@ out: } /** - * assign_requested_resources_sorted() - satisfy resource requests + * assign_requested_resources_sorted() - Satisfy resource requests * - * @head : head of the list tracking requests for resources - * @fail_head : head of the list tracking requests that could - * not be allocated + * @head: Head of the list tracking requests for resources + * @fail_head: Head of the list tracking requests that could not be + * allocated * - * Satisfy resource requests of each element in the list. Add - * requests that could not satisfied to the failed_list. + * Satisfy resource requests of each element in the list. Add requests that + * could not be satisfied to the failed_list. */ static void assign_requested_resources_sorted(struct list_head *head, struct list_head *fail_head) @@ -290,8 +285,9 @@ static void assign_requested_resources_sorted(struct list_head *head, pci_assign_resource(dev_res->dev, idx)) { if (fail_head) { /* - * if the failed res is for ROM BAR, and it will - * be enabled later, don't add it to the list + * If the failed resource is a ROM BAR and + * it will be enabled later, don't add it + * to the list. */ if (!((idx == PCI_ROM_RESOURCE) && (!(res->flags & IORESOURCE_ROM_ENABLE)))) @@ -310,15 +306,14 @@ static unsigned long pci_fail_res_type_mask(struct list_head *fail_head) struct pci_dev_resource *fail_res; unsigned long mask = 0; - /* check failed type */ + /* Check failed type */ list_for_each_entry(fail_res, fail_head, list) mask |= fail_res->flags; /* - * one pref failed resource will set IORESOURCE_MEM, - * as we can allocate pref in non-pref range. - * Will release all assigned non-pref sibling resources - * according to that bit. + * One pref failed resource will set IORESOURCE_MEM, as we can + * allocate pref in non-pref range. Will release all assigned + * non-pref sibling resources according to that bit. */ return mask & (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH); } @@ -328,11 +323,11 @@ static bool pci_need_to_release(unsigned long mask, struct resource *res) if (res->flags & IORESOURCE_IO) return !!(mask & IORESOURCE_IO); - /* check pref at first */ + /* Check pref at first */ if (res->flags & IORESOURCE_PREFETCH) { if (mask & IORESOURCE_PREFETCH) return true; - /* count pref if its parent is non-pref */ + /* Count pref if its parent is non-pref */ else if ((mask & IORESOURCE_MEM) && !(res->parent->flags & IORESOURCE_PREFETCH)) return true; @@ -343,33 +338,33 @@ static bool pci_need_to_release(unsigned long mask, struct resource *res) if (res->flags & IORESOURCE_MEM) return !!(mask & IORESOURCE_MEM); - return false; /* should not get here */ + return false; /* Should not get here */ } static void __assign_resources_sorted(struct list_head *head, - struct list_head *realloc_head, - struct list_head *fail_head) + struct list_head *realloc_head, + struct list_head *fail_head) { /* - * Should not assign requested resources at first. - * they could be adjacent, so later reassign can not reallocate - * them one by one in parent resource window. - * Try to assign requested + add_size at beginning - * if could do that, could get out early. - * if could not do that, we still try to assign requested at first, - * then try to reassign add_size for some resources. + * Should not assign requested resources at first. They could be + * adjacent, so later reassign can not reallocate them one by one in + * parent resource window. + * + * Try to assign requested + add_size at beginning. If could do that, + * could get out early. If could not do that, we still try to assign + * requested at first, then try to reassign add_size for some resources. * * Separate three resource type checking if we need to release * assigned resource after requested + add_size try. - * 1. if there is io port assign fail, will release assigned - * io port. - * 2. if there is pref mmio assign fail, release assigned - * pref mmio. - * if assigned pref mmio's parent is non-pref mmio and there - * is non-pref mmio assign fail, will release that assigned - * pref mmio. - * 3. if there is non-pref mmio assign fail or pref mmio - * assigned fail, will release assigned non-pref mmio. + * + * 1. If IO port assignment fails, will release assigned IO + * port. + * 2. If pref MMIO assignment fails, release assigned pref + * MMIO. If assigned pref MMIO's parent is non-pref MMIO + * and non-pref MMIO assignment fails, will release that + * assigned pref MMIO. + * 3. If non-pref MMIO assignment fails or pref MMIO + * assignment fails, will release assigned non-pref MMIO. */ LIST_HEAD(save_head); LIST_HEAD(local_fail_head); @@ -398,7 +393,7 @@ static void __assign_resources_sorted(struct list_head *head, /* * There are two kinds of additional resources in the list: * 1. bridge resource -- IORESOURCE_STARTALIGN - * 2. SR-IOV resource -- IORESOURCE_SIZEALIGN + * 2. SR-IOV resource -- IORESOURCE_SIZEALIGN * Here just fix the additional alignment for bridge */ if (!(dev_res->res->flags & IORESOURCE_STARTALIGN)) @@ -407,10 +402,10 @@ static void __assign_resources_sorted(struct list_head *head, add_align = get_res_add_align(realloc_head, dev_res->res); /* - * The "head" list is sorted by the alignment to make sure - * resources with bigger alignment will be assigned first. - * After we change the alignment of a dev_res in "head" list, - * we need to reorder the list by alignment to make it + * The "head" list is sorted by alignment so resources with + * bigger alignment will be assigned first. After we + * change the alignment of a dev_res in "head" list, we + * need to reorder the list by alignment to make it * consistent. */ if (add_align > dev_res->res->start) { @@ -435,7 +430,7 @@ static void __assign_resources_sorted(struct list_head *head, /* Try updated head list with add_size added */ assign_requested_resources_sorted(head, &local_fail_head); - /* all assigned with add_size ? */ + /* All assigned with add_size? */ if (list_empty(&local_fail_head)) { /* Remove head list from realloc_head list */ list_for_each_entry(dev_res, head, list) @@ -445,13 +440,13 @@ static void __assign_resources_sorted(struct list_head *head, return; } - /* check failed type */ + /* Check failed type */ fail_type = pci_fail_res_type_mask(&local_fail_head); - /* remove not need to be released assigned res from head list etc */ + /* Remove not need to be released assigned res from head list etc */ list_for_each_entry_safe(dev_res, tmp_res, head, list) if (dev_res->res->parent && !pci_need_to_release(fail_type, dev_res->res)) { - /* remove it from realloc_head list */ + /* Remove it from realloc_head list */ remove_from_list(realloc_head, dev_res->res); remove_from_list(&save_head, dev_res->res); list_del(&dev_res->list); @@ -477,16 +472,15 @@ requested_and_reassign: /* Satisfy the must-have resource requests */ assign_requested_resources_sorted(head, fail_head); - /* Try to satisfy any additional optional resource - requests */ + /* Try to satisfy any additional optional resource requests */ if (realloc_head) reassign_resources_sorted(realloc_head, head); free_list(head); } static void pdev_assign_resources_sorted(struct pci_dev *dev, - struct list_head *add_head, - struct list_head *fail_head) + struct list_head *add_head, + struct list_head *fail_head) { LIST_HEAD(head); @@ -563,17 +557,19 @@ void pci_setup_cardbus(struct pci_bus *bus) } EXPORT_SYMBOL(pci_setup_cardbus); -/* Initialize bridges with base/limit values we have collected. - PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998) - requires that if there is no I/O ports or memory behind the - bridge, corresponding range must be turned off by writing base - value greater than limit to the bridge's base/limit registers. - - Note: care must be taken when updating I/O base/limit registers - of bridges which support 32-bit I/O. This update requires two - config space writes, so it's quite possible that an I/O window of - the bridge will have some undesirable address (e.g. 0) after the - first write. Ditto 64-bit prefetchable MMIO. */ +/* + * Initialize bridges with base/limit values we have collected. PCI-to-PCI + * Bridge Architecture Specification rev. 1.1 (1998) requires that if there + * are no I/O ports or memory behind the bridge, the corresponding range + * must be turned off by writing base value greater than limit to the + * bridge's base/limit registers. + * + * Note: care must be taken when updating I/O base/limit registers of + * bridges which support 32-bit I/O. This update requires two config space + * writes, so it's quite possible that an I/O window of the bridge will + * have some undesirable address (e.g. 0) after the first write. Ditto + * 64-bit prefetchable MMIO. + */ static void pci_setup_bridge_io(struct pci_dev *bridge) { struct resource *res; @@ -587,7 +583,7 @@ static void pci_setup_bridge_io(struct pci_dev *bridge) if (bridge->io_window_1k) io_mask = PCI_IO_1K_RANGE_MASK; - /* Set up the top and bottom of the PCI I/O segment for this bus. */ + /* Set up the top and bottom of the PCI I/O segment for this bus */ res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_IO) { @@ -595,19 +591,19 @@ static void pci_setup_bridge_io(struct pci_dev *bridge) io_base_lo = (region.start >> 8) & io_mask; io_limit_lo = (region.end >> 8) & io_mask; l = ((u16) io_limit_lo << 8) | io_base_lo; - /* Set up upper 16 bits of I/O base/limit. */ + /* Set up upper 16 bits of I/O base/limit */ io_upper16 = (region.end & 0xffff0000) | (region.start >> 16); pci_info(bridge, " bridge window %pR\n", res); } else { - /* Clear upper 16 bits of I/O base/limit. */ + /* Clear upper 16 bits of I/O base/limit */ io_upper16 = 0; l = 0x00f0; } - /* Temporarily disable the I/O range before updating PCI_IO_BASE. */ + /* Temporarily disable the I/O range before updating PCI_IO_BASE */ pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff); - /* Update lower 16 bits of I/O base/limit. */ + /* Update lower 16 bits of I/O base/limit */ pci_write_config_word(bridge, PCI_IO_BASE, l); - /* Update upper 16 bits of I/O base/limit. */ + /* Update upper 16 bits of I/O base/limit */ pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16); } @@ -617,7 +613,7 @@ static void pci_setup_bridge_mmio(struct pci_dev *bridge) struct pci_bus_region region; u32 l; - /* Set up the top and bottom of the PCI Memory segment for this bus. */ + /* Set up the top and bottom of the PCI Memory segment for this bus */ res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_MEM) { @@ -636,12 +632,14 @@ static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge) struct pci_bus_region region; u32 l, bu, lu; - /* Clear out the upper 32 bits of PREF limit. - If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily - disables PREF range, which is ok. */ + /* + * Clear out the upper 32 bits of PREF limit. If + * PCI_PREF_BASE_UPPER32 was non-zero, this temporarily disables + * PREF range, which is ok. + */ pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0); - /* Set up PREF base/limit. */ + /* Set up PREF base/limit */ bu = lu = 0; res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2]; pcibios_resource_to_bus(bridge->bus, ®ion, res); @@ -658,7 +656,7 @@ static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge) } pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l); - /* Set the upper 32 bits of PREF base & limit. */ + /* Set the upper 32 bits of PREF base & limit */ pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu); pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu); } @@ -702,13 +700,13 @@ int pci_claim_bridge_resource(struct pci_dev *bridge, int i) return 0; if (pci_claim_resource(bridge, i) == 0) - return 0; /* claimed the window */ + return 0; /* Claimed the window */ if ((bridge->class >> 8) != PCI_CLASS_BRIDGE_PCI) return 0; if (!pci_bus_clip_resource(bridge, i)) - return -EINVAL; /* clipping didn't change anything */ + return -EINVAL; /* Clipping didn't change anything */ switch (i - PCI_BRIDGE_RESOURCES) { case 0: @@ -725,14 +723,16 @@ int pci_claim_bridge_resource(struct pci_dev *bridge, int i) } if (pci_claim_resource(bridge, i) == 0) - return 0; /* claimed a smaller window */ + return 0; /* Claimed a smaller window */ return -EINVAL; } -/* Check whether the bridge supports optional I/O and - prefetchable memory ranges. If not, the respective - base/limit registers must be read-only and read as 0. */ +/* + * Check whether the bridge supports optional I/O and prefetchable memory + * ranges. If not, the respective base/limit registers must be read-only + * and read as 0. + */ static void pci_bridge_check_ranges(struct pci_bus *bus) { struct pci_dev *bridge = bus->self; @@ -752,12 +752,14 @@ static void pci_bridge_check_ranges(struct pci_bus *bus) } } -/* Helper function for sizing routines: find first available - bus resource of a given type. Note: we intentionally skip - the bus resources which have already been assigned (that is, - have non-NULL parent resource). */ +/* + * Helper function for sizing routines: find first available bus resource + * of a given type. Note: we intentionally skip the bus resources which + * have already been assigned (that is, have non-NULL parent resource). + */ static struct resource *find_free_bus_resource(struct pci_bus *bus, - unsigned long type_mask, unsigned long type) + unsigned long type_mask, + unsigned long type) { int i; struct resource *r; @@ -772,19 +774,21 @@ static struct resource *find_free_bus_resource(struct pci_bus *bus, } static resource_size_t calculate_iosize(resource_size_t size, - resource_size_t min_size, - resource_size_t size1, - resource_size_t add_size, - resource_size_t children_add_size, - resource_size_t old_size, - resource_size_t align) + resource_size_t min_size, + resource_size_t size1, + resource_size_t add_size, + resource_size_t children_add_size, + resource_size_t old_size, + resource_size_t align) { if (size < min_size) size = min_size; if (old_size == 1) old_size = 0; - /* To be fixed in 2.5: we should have sort of HAVE_ISA - flag in the struct pci_bus. */ + /* + * To be fixed in 2.5: we should have sort of HAVE_ISA flag in the + * struct pci_bus. + */ #if defined(CONFIG_ISA) || defined(CONFIG_EISA) size = (size & 0xff) + ((size & ~0xffUL) << 2); #endif @@ -797,11 +801,11 @@ static resource_size_t calculate_iosize(resource_size_t size, } static resource_size_t calculate_memsize(resource_size_t size, - resource_size_t min_size, - resource_size_t add_size, - resource_size_t children_add_size, - resource_size_t old_size, - resource_size_t align) + resource_size_t min_size, + resource_size_t add_size, + resource_size_t children_add_size, + resource_size_t old_size, + resource_size_t align) { if (size < min_size) size = min_size; @@ -824,8 +828,7 @@ resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, #define PCI_P2P_DEFAULT_IO_ALIGN 0x1000 /* 4KiB */ #define PCI_P2P_DEFAULT_IO_ALIGN_1K 0x400 /* 1KiB */ -static resource_size_t window_alignment(struct pci_bus *bus, - unsigned long type) +static resource_size_t window_alignment(struct pci_bus *bus, unsigned long type) { resource_size_t align = 1, arch_align; @@ -833,8 +836,8 @@ static resource_size_t window_alignment(struct pci_bus *bus, align = PCI_P2P_DEFAULT_MEM_ALIGN; else if (type & IORESOURCE_IO) { /* - * Per spec, I/O windows are 4K-aligned, but some - * bridges have an extension to support 1K alignment. + * Per spec, I/O windows are 4K-aligned, but some bridges have + * an extension to support 1K alignment. */ if (bus->self->io_window_1k) align = PCI_P2P_DEFAULT_IO_ALIGN_1K; @@ -847,20 +850,21 @@ static resource_size_t window_alignment(struct pci_bus *bus, } /** - * pbus_size_io() - size the io window of a given bus + * pbus_size_io() - Size the I/O window of a given bus * - * @bus : the bus - * @min_size : the minimum io window that must to be allocated - * @add_size : additional optional io window - * @realloc_head : track the additional io window on this list + * @bus: The bus + * @min_size: The minimum I/O window that must be allocated + * @add_size: Additional optional I/O window + * @realloc_head: Track the additional I/O window on this list * - * Sizing the IO windows of the PCI-PCI bridge is trivial, - * since these windows have 1K or 4K granularity and the IO ranges - * of non-bridge PCI devices are limited to 256 bytes. - * We must be careful with the ISA aliasing though. + * Sizing the I/O windows of the PCI-PCI bridge is trivial, since these + * windows have 1K or 4K granularity and the I/O ranges of non-bridge PCI + * devices are limited to 256 bytes. We must be careful with the ISA + * aliasing though. */ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, - resource_size_t add_size, struct list_head *realloc_head) + resource_size_t add_size, + struct list_head *realloc_head) { struct pci_dev *dev; struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO, @@ -947,33 +951,33 @@ static inline resource_size_t calculate_mem_align(resource_size_t *aligns, } /** - * pbus_size_mem() - size the memory window of a given bus + * pbus_size_mem() - Size the memory window of a given bus * - * @bus : the bus - * @mask: mask the resource flag, then compare it with type - * @type: the type of free resource from bridge - * @type2: second match type - * @type3: third match type - * @min_size : the minimum memory window that must to be allocated - * @add_size : additional optional memory window - * @realloc_head : track the additional memory window on this list + * @bus: The bus + * @mask: Mask the resource flag, then compare it with type + * @type: The type of free resource from bridge + * @type2: Second match type + * @type3: Third match type + * @min_size: The minimum memory window that must be allocated + * @add_size: Additional optional memory window + * @realloc_head: Track the additional memory window on this list * - * Calculate the size of the bus and minimal alignment which - * guarantees that all child resources fit in this size. + * Calculate the size of the bus and minimal alignment which guarantees + * that all child resources fit in this size. * - * Returns -ENOSPC if there's no available bus resource of the desired type. - * Otherwise, sets the bus resource start/end to indicate the required - * size, adds things to realloc_head (if supplied), and returns 0. + * Return -ENOSPC if there's no available bus resource of the desired + * type. Otherwise, set the bus resource start/end to indicate the + * required size, add things to realloc_head (if supplied), and return 0. */ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type, unsigned long type2, - unsigned long type3, - resource_size_t min_size, resource_size_t add_size, + unsigned long type3, resource_size_t min_size, + resource_size_t add_size, struct list_head *realloc_head) { struct pci_dev *dev; resource_size_t min_align, align, size, size0, size1; - resource_size_t aligns[18]; /* Alignments from 1Mb to 128Gb */ + resource_size_t aligns[18]; /* Alignments from 1MB to 128GB */ int order, max_order; struct resource *b_res = find_free_bus_resource(bus, mask | IORESOURCE_PREFETCH, type); @@ -1002,12 +1006,12 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, continue; r_size = resource_size(r); #ifdef CONFIG_PCI_IOV - /* put SRIOV requested res to the optional list */ + /* Put SRIOV requested res to the optional list */ if (realloc_head && i >= PCI_IOV_RESOURCES && i <= PCI_IOV_RESOURCE_END) { add_align = max(pci_resource_alignment(dev, r), add_align); r->end = r->start - 1; - add_to_list(realloc_head, dev, r, r_size, 0/* don't care */); + add_to_list(realloc_head, dev, r, r_size, 0 /* Don't care */); children_add_size += r_size; continue; } @@ -1029,8 +1033,10 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, continue; } size += max(r_size, align); - /* Exclude ranges with size > align from - calculation of the alignment. */ + /* + * Exclude ranges with size > align from calculation of + * the alignment. + */ if (r_size <= align) aligns[order] += align; if (order > max_order) @@ -1081,7 +1087,7 @@ unsigned long pci_cardbus_resource_alignment(struct resource *res) } static void pci_bus_size_cardbus(struct pci_bus *bus, - struct list_head *realloc_head) + struct list_head *realloc_head) { struct pci_dev *bridge = bus->self; struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; @@ -1091,8 +1097,8 @@ static void pci_bus_size_cardbus(struct pci_bus *bus, if (b_res[0].parent) goto handle_b_res_1; /* - * Reserve some resources for CardBus. We reserve - * a fixed amount of bus space for CardBus bridges. + * Reserve some resources for CardBus. We reserve a fixed amount + * of bus space for CardBus bridges. */ b_res[0].start = pci_cardbus_io_size; b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1; @@ -1116,7 +1122,7 @@ handle_b_res_1: } handle_b_res_2: - /* MEM1 must not be pref mmio */ + /* MEM1 must not be pref MMIO */ pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) { ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1; @@ -1124,10 +1130,7 @@ handle_b_res_2: pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); } - /* - * Check whether prefetchable memory is supported - * by this bridge. - */ + /* Check whether prefetchable memory is supported by this bridge. */ pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) { ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0; @@ -1138,9 +1141,8 @@ handle_b_res_2: if (b_res[2].parent) goto handle_b_res_3; /* - * If we have prefetchable memory support, allocate - * two regions. Otherwise, allocate one region of - * twice the size. + * If we have prefetchable memory support, allocate two regions. + * Otherwise, allocate one region of twice the size. */ if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) { b_res[2].start = pci_cardbus_mem_size; @@ -1153,7 +1155,7 @@ handle_b_res_2: pci_cardbus_mem_size, pci_cardbus_mem_size); } - /* reduce that to half */ + /* Reduce that to half */ b_res_3_size = pci_cardbus_mem_size; } @@ -1204,7 +1206,7 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head) switch (bus->self->hdr_type) { case PCI_HEADER_TYPE_CARDBUS: - /* don't size cardbuses yet. */ + /* Don't size CardBuses yet */ break; case PCI_HEADER_TYPE_BRIDGE: @@ -1271,18 +1273,17 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head) /* * Compute the size required to put everything else in the - * non-prefetchable window. This includes: + * non-prefetchable window. This includes: * * - all non-prefetchable resources * - 32-bit prefetchable resources if there's a 64-bit * prefetchable window or no prefetchable window at all - * - 64-bit prefetchable resources if there's no - * prefetchable window at all + * - 64-bit prefetchable resources if there's no prefetchable + * window at all * - * Note that the strategy in __pci_assign_resource() must - * match that used here. Specifically, we cannot put a - * 32-bit prefetchable resource in a 64-bit prefetchable - * window. + * Note that the strategy in __pci_assign_resource() must match + * that used here. Specifically, we cannot put a 32-bit + * prefetchable resource in a 64-bit prefetchable window. */ pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3, realloc_head ? 0 : additional_mem_size, @@ -1315,8 +1316,8 @@ static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r) } /* - * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they - * are skipped by pbus_assign_resources_sorted(). + * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they are + * skipped by pbus_assign_resources_sorted(). */ static void pdev_assign_fixed_resources(struct pci_dev *dev) { @@ -1427,10 +1428,9 @@ static void pci_bus_allocate_resources(struct pci_bus *b) struct pci_bus *child; /* - * Carry out a depth-first search on the PCI bus - * tree to allocate bridge apertures. Read the - * programmed bridge bases and recursively claim - * the respective bridge resources. + * Carry out a depth-first search on the PCI bus tree to allocate + * bridge apertures. Read the programmed bridge bases and + * recursively claim the respective bridge resources. */ if (b->self) { pci_read_bridge_bases(b); @@ -1484,7 +1484,7 @@ static void __pci_bridge_assign_resources(const struct pci_dev *bridge, IORESOURCE_MEM_64) static void pci_bridge_release_resources(struct pci_bus *bus, - unsigned long type) + unsigned long type) { struct pci_dev *dev = bus->self; struct resource *r; @@ -1495,16 +1495,14 @@ static void pci_bridge_release_resources(struct pci_bus *bus, b_res = &dev->resource[PCI_BRIDGE_RESOURCES]; /* - * 1. if there is io port assign fail, will release bridge - * io port. - * 2. if there is non pref mmio assign fail, release bridge - * nonpref mmio. - * 3. if there is 64bit pref mmio assign fail, and bridge pref - * is 64bit, release bridge pref mmio. - * 4. if there is pref mmio assign fail, and bridge pref is - * 32bit mmio, release bridge pref mmio - * 5. if there is pref mmio assign fail, and bridge pref is not - * assigned, release bridge nonpref mmio. + * 1. If IO port assignment fails, release bridge IO port. + * 2. If non pref MMIO assignment fails, release bridge nonpref MMIO. + * 3. If 64bit pref MMIO assignment fails, and bridge pref is 64bit, + * release bridge pref MMIO. + * 4. If pref MMIO assignment fails, and bridge pref is 32bit, + * release bridge pref MMIO. + * 5. If pref MMIO assignment fails, and bridge pref is not + * assigned, release bridge nonpref MMIO. */ if (type & IORESOURCE_IO) idx = 0; @@ -1524,25 +1522,22 @@ static void pci_bridge_release_resources(struct pci_bus *bus, if (!r->parent) return; - /* - * if there are children under that, we should release them - * all - */ + /* If there are children, release them all */ release_child_resources(r); if (!release_resource(r)) { type = old_flags = r->flags & PCI_RES_TYPE_MASK; pci_printk(KERN_DEBUG, dev, "resource %d %pR released\n", PCI_BRIDGE_RESOURCES + idx, r); - /* keep the old size */ + /* Keep the old size */ r->end = resource_size(r) - 1; r->start = 0; r->flags = 0; - /* avoiding touch the one without PREF */ + /* Avoiding touch the one without PREF */ if (type & IORESOURCE_PREFETCH) type = IORESOURCE_PREFETCH; __pci_setup_bridge(bus, type); - /* for next child res under same bridge */ + /* For next child res under same bridge */ r->flags = old_flags; } } @@ -1551,9 +1546,10 @@ enum release_type { leaf_only, whole_subtree, }; + /* - * try to release pci bridge resources that is from leaf bridge, - * so we can allocate big new one later + * Try to release PCI bridge resources from leaf bridge, so we can allocate + * a larger window later. */ static void pci_bus_release_bridge_resources(struct pci_bus *bus, unsigned long type, @@ -1678,7 +1674,7 @@ static int iov_resources_unassigned(struct pci_dev *dev, void *data) pcibios_resource_to_bus(dev->bus, ®ion, r); if (!region.start) { *unassigned = true; - return 1; /* return early from pci_walk_bus() */ + return 1; /* Return early from pci_walk_bus() */ } } @@ -1686,7 +1682,7 @@ static int iov_resources_unassigned(struct pci_dev *dev, void *data) } static enum enable_type pci_realloc_detect(struct pci_bus *bus, - enum enable_type enable_local) + enum enable_type enable_local) { bool unassigned = false; @@ -1701,21 +1697,21 @@ static enum enable_type pci_realloc_detect(struct pci_bus *bus, } #else static enum enable_type pci_realloc_detect(struct pci_bus *bus, - enum enable_type enable_local) + enum enable_type enable_local) { return enable_local; } #endif /* - * first try will not touch pci bridge res - * second and later try will clear small leaf bridge res - * will stop till to the max depth if can not find good one + * First try will not touch PCI bridge res. + * Second and later try will clear small leaf bridge res. + * Will stop till to the max depth if can not find good one. */ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus) { - LIST_HEAD(realloc_head); /* list of resources that - want additional resources */ + LIST_HEAD(realloc_head); + /* List of resources that want additional resources */ struct list_head *add_list = NULL; int tried_times = 0; enum release_type rel_type = leaf_only; @@ -1724,7 +1720,7 @@ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus) int pci_try_num = 1; enum enable_type enable_local; - /* don't realloc if asked to do so */ + /* Don't realloc if asked to do so */ enable_local = pci_realloc_detect(bus, pci_realloc_enable); if (pci_realloc_enabled(enable_local)) { int max_depth = pci_bus_get_depth(bus); @@ -1737,13 +1733,14 @@ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus) again: /* - * last try will use add_list, otherwise will try good to have as - * must have, so can realloc parent bridge resource + * Last try will use add_list, otherwise will try good to have as must + * have, so can realloc parent bridge resource */ if (tried_times + 1 == pci_try_num) add_list = &realloc_head; - /* Depth first, calculate sizes and alignments of all - subordinate buses. */ + /* + * Depth first, calculate sizes and alignments of all subordinate buses. + */ __pci_bus_size_bridges(bus, add_list); /* Depth last, allocate resources and update the hardware. */ @@ -1752,7 +1749,7 @@ again: BUG_ON(!list_empty(add_list)); tried_times++; - /* any device complain? */ + /* Any device complain? */ if (list_empty(&fail_head)) goto dump; @@ -1769,20 +1766,20 @@ again: dev_printk(KERN_DEBUG, &bus->dev, "No. %d try to assign unassigned res\n", tried_times + 1); - /* third times and later will not check if it is leaf */ + /* Third times and later will not check if it is leaf */ if ((tried_times + 1) > 2) rel_type = whole_subtree; /* * Try to release leaf bridge's resources that doesn't fit resource of - * child device under that bridge + * child device under that bridge. */ list_for_each_entry(fail_res, &fail_head, list) pci_bus_release_bridge_resources(fail_res->dev->bus, fail_res->flags & PCI_RES_TYPE_MASK, rel_type); - /* restore size and flags */ + /* Restore size and flags */ list_for_each_entry(fail_res, &fail_head, list) { struct resource *res = fail_res->res; @@ -1797,7 +1794,7 @@ again: goto again; dump: - /* dump the resource on buses */ + /* Dump the resource on buses */ pci_bus_dump_resources(bus); } @@ -1808,14 +1805,15 @@ void __init pci_assign_unassigned_resources(void) list_for_each_entry(root_bus, &pci_root_buses, node) { pci_assign_unassigned_root_bus_resources(root_bus); - /* Make sure the root bridge has a companion ACPI device: */ + /* Make sure the root bridge has a companion ACPI device */ if (ACPI_HANDLE(root_bus->bridge)) acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge)); } } static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, - struct list_head *add_list, resource_size_t available) + struct list_head *add_list, + resource_size_t available) { struct pci_dev_resource *dev_res; @@ -1839,8 +1837,10 @@ static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, } static void pci_bus_distribute_available_resources(struct pci_bus *bus, - struct list_head *add_list, resource_size_t available_io, - resource_size_t available_mmio, resource_size_t available_mmio_pref) + struct list_head *add_list, + resource_size_t available_io, + resource_size_t available_mmio, + resource_size_t available_mmio_pref) { resource_size_t remaining_io, remaining_mmio, remaining_mmio_pref; unsigned int normal_bridges = 0, hotplug_bridges = 0; @@ -1864,7 +1864,7 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, /* * Calculate the total amount of extra resource space we can - * pass to bridges below this one. This is basically the + * pass to bridges below this one. This is basically the * extra space reduced by the minimal required space for the * non-hotplug bridges. */ @@ -1874,7 +1874,7 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, /* * Calculate how many hotplug bridges and normal bridges there - * are on this bus. We will distribute the additional available + * are on this bus. We will distribute the additional available * resources between hotplug bridges. */ for_each_pci_bridge(dev, bus) { @@ -1909,8 +1909,8 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, /* * There is only one bridge on the bus so it gets all available - * resources which it can then distribute to the possible - * hotplug bridges below. + * resources which it can then distribute to the possible hotplug + * bridges below. */ if (hotplug_bridges + normal_bridges == 1) { dev = list_first_entry(&bus->devices, struct pci_dev, bus_list); @@ -1961,9 +1961,8 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, } } -static void -pci_bridge_distribute_available_resources(struct pci_dev *bridge, - struct list_head *add_list) +static void pci_bridge_distribute_available_resources(struct pci_dev *bridge, + struct list_head *add_list) { resource_size_t available_io, available_mmio, available_mmio_pref; const struct resource *res; @@ -1980,14 +1979,17 @@ pci_bridge_distribute_available_resources(struct pci_dev *bridge, available_mmio_pref = resource_size(res); pci_bus_distribute_available_resources(bridge->subordinate, - add_list, available_io, available_mmio, available_mmio_pref); + add_list, available_io, + available_mmio, + available_mmio_pref); } void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge) { struct pci_bus *parent = bridge->subordinate; - LIST_HEAD(add_list); /* list of resources that - want additional resources */ + /* List of resources that want additional resources */ + LIST_HEAD(add_list); + int tried_times = 0; LIST_HEAD(fail_head); struct pci_dev_resource *fail_res; @@ -1997,9 +1999,9 @@ again: __pci_bus_size_bridges(parent, &add_list); /* - * Distribute remaining resources (if any) equally between - * hotplug bridges below. This makes it possible to extend the - * hierarchy later without running out of resources. + * Distribute remaining resources (if any) equally between hotplug + * bridges below. This makes it possible to extend the hierarchy + * later without running out of resources. */ pci_bridge_distribute_available_resources(bridge, &add_list); @@ -2011,7 +2013,7 @@ again: goto enable_all; if (tried_times >= 2) { - /* still fail, don't need to try more */ + /* Still fail, don't need to try more */ free_list(&fail_head); goto enable_all; } @@ -2020,15 +2022,15 @@ again: tried_times + 1); /* - * Try to release leaf bridge's resources that doesn't fit resource of - * child device under that bridge + * Try to release leaf bridge's resources that aren't big enough + * to contain child device resources. */ list_for_each_entry(fail_res, &fail_head, list) pci_bus_release_bridge_resources(fail_res->dev->bus, fail_res->flags & PCI_RES_TYPE_MASK, whole_subtree); - /* restore size and flags */ + /* Restore size and flags */ list_for_each_entry(fail_res, &fail_head, list) { struct resource *res = fail_res->res; @@ -2107,7 +2109,7 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type) } list_for_each_entry(dev_res, &saved, list) { - /* Skip the bridge we just assigned resources for. */ + /* Skip the bridge we just assigned resources for */ if (bridge == dev_res->dev) continue; @@ -2119,7 +2121,7 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type) return 0; cleanup: - /* restore size and flags */ + /* Restore size and flags */ list_for_each_entry(dev_res, &failed, list) { struct resource *res = dev_res->res; @@ -2151,8 +2153,8 @@ cleanup: void pci_assign_unassigned_bus_resources(struct pci_bus *bus) { struct pci_dev *dev; - LIST_HEAD(add_list); /* list of resources that - want additional resources */ + /* List of resources that want additional resources */ + LIST_HEAD(add_list); down_read(&pci_bus_sem); for_each_pci_bridge(dev, bus) |