Subject: [RFC v2 2/7] ia64/PCI/ACPI: Use common ACPI resource parsing interface for host bridge

From: [email-masked] (Hanjun Guo)
Date: Mon, 11 May 2015 21:04:42 +0800

On 2015?05?05? 10:46, Jiang Liu wrote:
> Use common ACPI resource parsing interface to parse ACPI resources for
> PCI host bridge, so we could share more code between IA64 and x86.
> Later we will consolidate arch specific implementations into ACPI core.
>
> Tested-by: Tony Luck <[email-masked]>
> Signed-off-by: Jiang Liu <[email-masked]>
> ---
>   arch/ia64/pci/pci.c |  414 ++++++++++++++++++++++++---------------------------
>   1 file changed, 193 insertions(+), 221 deletions(-)

Because the first version of ACPI base host bridge init for ARM64
is copied from  IA64, so I also familiar with this code, and
the changes in this patch is ok to me, so

Reviewed-by: Hanjun Guo <[email-masked]>

Thanks
hanjun

>
> diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
> index d4e162d35b34..23689d4c37ae 100644
> --- a/arch/ia64/pci/pci.c
> +++ b/arch/ia64/pci/pci.c
> @@ -115,29 +115,12 @@ struct pci_ops pci_root_ops = {
>   	.write = pci_write,
>   };
>
> -/* Called by ACPI when it finds a new root bus.  */
> -
> -static struct pci_controller *alloc_pci_controller(int seg)
> -{
> -	struct pci_controller *controller;
> -
> -	controller = kzalloc(sizeof(*controller), GFP_KERNEL);
> -	if (!controller)
> -		return NULL;
> -
> -	controller->segment = seg;
> -	return controller;
> -}
> -
>   struct pci_root_info {
> +	struct pci_controller controller;
>   	struct acpi_device *bridge;
> -	struct pci_controller *controller;
>   	struct list_head resources;
> -	struct resource *res;
> -	resource_size_t *res_offset;
> -	unsigned int res_num;
>   	struct list_head io_resources;
> -	char *name;
> +	char name[16];
>   };
>
>   static unsigned int
> @@ -168,11 +151,11 @@ new_space (u64 phys_base, int sparse)
>   	return i;
>   }
>
> -static u64 add_io_space(struct pci_root_info *info,
> -			struct acpi_resource_address64 *addr)
> +static int add_io_space(struct device *dev, struct pci_root_info *info,
> +			struct resource_entry *entry)
>   {
>   	struct iospace_resource *iospace;
> -	struct resource *resource;
> +	struct resource *resource, *res = entry->res;
>   	char *name;
>   	unsigned long base, min, max, base_port;
>   	unsigned int sparse = 0, space_nr, len;
> @@ -180,27 +163,24 @@ static u64 add_io_space(struct pci_root_info *info,
>   	len = strlen(info->name) + 32;
>   	iospace = kzalloc(sizeof(*iospace) + len, GFP_KERNEL);
>   	if (!iospace) {
> -		dev_err(&info->bridge->dev,
> -				"PCI: No memory for %s I/O port space\n",
> -				info->name);
> -		goto out;
> +		dev_err(dev, "PCI: No memory for %s I/O port space\n",
> +			info->name);
> +		return -ENOMEM;
>   	}
>
> -	name = (char *)(iospace + 1);
> -
> -	min = addr->address.minimum;
> -	max = min + addr->address.address_length - 1;
> -	if (addr->info.io.translation_type == ACPI_SPARSE_TRANSLATION)
> +	if (res->flags & IORESOURCE_IO_SPARSE)
>   		sparse = 1;
> -
> -	space_nr = new_space(addr->address.translation_offset, sparse);
> +	space_nr = new_space(entry->offset, sparse);
>   	if (space_nr == ~0)
>   		goto free_resource;
>
> +	name = (char *)(iospace + 1);
> +	min = res->start - entry->offset;
> +	max = res->end - entry->offset;
>   	base = __pa(io_space[space_nr].mmio_base);
>   	base_port = IO_SPACE_BASE(space_nr);
>   	snprintf(name, len, "%s I/O Ports %08lx-%08lx", info->name,
> -		base_port + min, base_port + max);
> +		 base_port + min, base_port + max);
>
>   	/*
>   	 * The SDM guarantees the legacy 0-64K space is sparse, but if the
> @@ -216,153 +196,195 @@ static u64 add_io_space(struct pci_root_info *info,
>   	resource->start = base + (sparse ? IO_SPACE_SPARSE_ENCODING(min) : min);
>   	resource->end   = base + (sparse ? IO_SPACE_SPARSE_ENCODING(max) : max);
>   	if (insert_resource(&iomem_resource, resource)) {
> -		dev_err(&info->bridge->dev,
> -				"can't allocate host bridge io space resource  %pR\n",
> -				resource);
> +		dev_err(dev,
> +			"can't allocate host bridge io space resource  %pR\n",
> +			resource);
>   		goto free_resource;
>   	}
>
> +	entry->offset = base_port;
> +	res->start = min + base_port;
> +	res->end = max + base_port;
>   	list_add_tail(&iospace->list, &info->io_resources);
> -	return base_port;
> +
> +	return 0;
>
>   free_resource:
>   	kfree(iospace);
> -out:
> -	return ~0;
> +	return -ENOSPC;
> +}
> +
> +/*
> + * An IO port or MMIO resource assigned to a PCI host bridge may be
> + * consumed by the host bridge itself or available to its child
> + * bus/devices. The ACPI specification defines a bit (Producer/Consumer)
> + * to tell whether the resource is consumed by the host bridge itself,
> + * but firmware hasn't used that bit consistently, so we can't rely on it.
> + *
> + * On x86 and IA64 platforms, all IO port and MMIO resources are assumed
> + * to be available to child bus/devices except one special case:
> + *     IO port [0xCF8-0xCFF] is consumed by the host bridge itself
> + *     to access PCI configuration space.
> + *
> + * So explicitly filter out PCI CFG IO ports[0xCF8-0xCFF].
> + */
> +static bool resource_is_pcicfg_ioport(struct resource *res)
> +{
> +	return (res->flags & IORESOURCE_IO) &&
> +		res->start == 0xCF8 && res->end == 0xCFF;
>   }
>
> -static acpi_status resource_to_window(struct acpi_resource *resource,
> -				      struct acpi_resource_address64 *addr)
> +static int
> +probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
> +		    int busnum, int domain)
>   {
> -	acpi_status status;
> +	int ret;
> +	struct list_head *list = &info->resources;
> +	struct resource_entry *entry, *tmp;
>
> -	/*
> -	 * We're only interested in _CRS descriptors that are
> -	 *	- address space descriptors for memory or I/O space
> -	 *	- non-zero size
> -	 */
> -	status = acpi_resource_to_address64(resource, addr);
> -	if (ACPI_SUCCESS(status) &&
> -	    (addr->resource_type == ACPI_MEMORY_RANGE ||
> -	     addr->resource_type == ACPI_IO_RANGE) &&
> -	    addr->address.address_length)
> -		return AE_OK;
> -
> -	return AE_ERROR;
> -}
> -
> -static acpi_status count_window(struct acpi_resource *resource, void *data)
> -{
> -	unsigned int *windows = (unsigned int *) data;
> -	struct acpi_resource_address64 addr;
> -	acpi_status status;
> -
> -	status = resource_to_window(resource, &addr);
> -	if (ACPI_SUCCESS(status))
> -		(*windows)++;
> -
> -	return AE_OK;
> -}
> -
> -static acpi_status add_window(struct acpi_resource *res, void *data)
> -{
> -	struct pci_root_info *info = data;
> -	struct resource *resource;
> -	struct acpi_resource_address64 addr;
> -	acpi_status status;
> -	unsigned long flags, offset = 0;
> -	struct resource *root;
> -
> -	/* Return AE_OK for non-window resources to keep scanning for more */
> -	status = resource_to_window(res, &addr);
> -	if (!ACPI_SUCCESS(status))
> -		return AE_OK;
> -
> -	if (addr.resource_type == ACPI_MEMORY_RANGE) {
> -		flags = IORESOURCE_MEM;
> -		root = &iomem_resource;
> -		offset = addr.address.translation_offset;
> -	} else if (addr.resource_type == ACPI_IO_RANGE) {
> -		flags = IORESOURCE_IO;
> -		root = &ioport_resource;
> -		offset = add_io_space(info, &addr);
> -		if (offset == ~0)
> -			return AE_OK;
> -	} else
> -		return AE_OK;
> -
> -	resource = &info->res[info->res_num];
> -	resource->name = info->name;
> -	resource->flags = flags;
> -	resource->start = addr.address.minimum + offset;
> -	resource->end = resource->start + addr.address.address_length - 1;
> -	info->res_offset[info->res_num] = offset;
> -
> -	if (insert_resource(root, resource)) {
> -		dev_err(&info->bridge->dev,
> -			"can't allocate host bridge window %pR\n",
> -			resource);
> -	} else {
> -		if (offset)
> -			dev_info(&info->bridge->dev, "host bridge window %pR "
> -				 "(PCI address [%#llx-%#llx])\n",
> -				 resource,
> -				 resource->start - offset,
> -				 resource->end - offset);
> -		else
> -			dev_info(&info->bridge->dev,
> -				 "host bridge window %pR\n", resource);
> -	}
> -	/* HP's firmware has a hack to work around a Windows bug.
> -	 * Ignore these tiny memory ranges */
> -	if (!((resource->flags & IORESOURCE_MEM) &&
> -	      (resource->end - resource->start < 16)))
> -		pci_add_resource_offset(&info->resources, resource,
> -					info->res_offset[info->res_num]);
> +	ret = acpi_dev_get_resources(device, list,
> +				     acpi_dev_filter_resource_type_cb,
> +				     (void *)(IORESOURCE_IO | IORESOURCE_MEM));
> +	if (ret < 0)
> +		dev_warn(&device->dev,
> +			 "failed to parse _CRS method, error code %d\n", ret);
> +	else if (ret == 0)
> +		dev_dbg(&device->dev,
> +			"no IO and memory resources present in _CRS\n");
> +	else
> +		resource_list_for_each_entry_safe(entry, tmp, list) {
> +			if ((entry->res->flags & IORESOURCE_DISABLED) ||
> +			    resource_is_pcicfg_ioport(entry->res))
> +				resource_list_destroy_entry(entry);
> +			else
> +				entry->res->name = info->name;
> +		}
>
> -	info->res_num++;
> -	return AE_OK;
> +	return ret;
>   }
>
> -static void free_pci_root_info_res(struct pci_root_info *info)
> -{
> -	struct iospace_resource *iospace, *tmp;
> +static void validate_resources(struct device *dev, struct list_head *resources,
> +			       unsigned long type)
> +{
> +	LIST_HEAD(list);
> +	struct resource *res1, *res2, *root = NULL;
> +	struct resource_entry *tmp, *entry, *entry2;
> +
> +	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
> +	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
> +
> +	list_splice_init(resources, &list);
> +	resource_list_for_each_entry_safe(entry, tmp, &list) {
> +		bool free = false;
> +		resource_size_t end;
> +
> +		res1 = entry->res;
> +		if (!(res1->flags & type))
> +			goto next;
> +
> +		/* Exclude non-addressable range or non-addressable portion */
> +		end = min(res1->end, root->end);
> +		if (end <= res1->start) {
> +			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
> +				 res1);
> +			free = true;
> +			goto next;
> +		} else if (res1->end != end) {
> +			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
> +				 res1, (unsigned long long)end + 1,
> +				 (unsigned long long)res1->end);
> +			res1->end = end;
> +		}
>
> -	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list)
> -		kfree(iospace);
> +		resource_list_for_each_entry(entry2, resources) {
> +			res2 = entry2->res;
> +			if (!(res2->flags & type))
> +				continue;
> +
> +			/*
> +			 * I don't like throwing away windows because then
> +			 * our resources no longer match the ACPI _CRS, but
> +			 * the kernel resource tree doesn't allow overlaps.
> +			 */
> +			if (resource_overlaps(res1, res2)) {
> +				res2->start = min(res1->start, res2->start);
> +				res2->end = max(res1->end, res2->end);
> +				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
> +					 res2, res1);
> +				free = true;
> +				goto next;
> +			}
> +		}
>
> -	kfree(info->name);
> -	kfree(info->res);
> -	info->res = NULL;
> -	kfree(info->res_offset);
> -	info->res_offset = NULL;
> -	info->res_num = 0;
> -	kfree(info->controller);
> -	info->controller = NULL;
> +next:
> +		resource_list_del(entry);
> +		if (free)
> +			resource_list_free_entry(entry);
> +		else
> +			resource_list_add_tail(entry, resources);
> +	}
> +}
> +
> +static void add_resources(struct pci_root_info *info, struct device *dev)
> +{
> +	struct resource_entry *entry, *tmp;
> +	struct resource *res, *conflict, *root = NULL;
> +	struct list_head *list = &info->resources;
> +
> +	validate_resources(dev, list, IORESOURCE_MEM);
> +	validate_resources(dev, list, IORESOURCE_IO);
> +
> +	resource_list_for_each_entry_safe(entry, tmp, list) {
> +		res = entry->res;
> +		if (res->flags & IORESOURCE_MEM) {
> +			root = &iomem_resource;
> +			/*
> +			 * HP's firmware has a hack to work around a Windows
> +			 * bug. Ignore these tiny memory ranges.
> +			 */
> +			if (resource_size(res) <= 16) {
> +				resource_list_destroy_entry(entry);
> +				continue;
> +			}
> +		} else if (res->flags & IORESOURCE_IO) {
> +			root = &ioport_resource;
> +			if (add_io_space(&info->bridge->dev, info, entry)) {
> +				resource_list_destroy_entry(entry);
> +				continue;
> +			}
> +		} else {
> +			BUG_ON(res);
> +		}
> +
> +		conflict = insert_resource_conflict(root, res);
> +		if (conflict) {
> +			dev_info(dev,
> +				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
> +				 res, conflict->name, conflict);
> +			resource_list_destroy_entry(entry);
> +		}
> +	}
>   }
>
>   static void __release_pci_root_info(struct pci_root_info *info)
>   {
> -	int i;
>   	struct resource *res;
> -	struct iospace_resource *iospace;
> +	struct iospace_resource *iospace, *tmp;
> +	struct resource_entry *entry, *tentry;
>
> -	list_for_each_entry(iospace, &info->io_resources, list)
> +	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list) {
>   		release_resource(&iospace->res);
> +		kfree(iospace);
> +	}
>
> -	for (i = 0; i < info->res_num; i++) {
> -		res = &info->res[i];
> -
> -		if (!res->parent)
> -			continue;
> -
> -		if (!(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
> -			continue;
> -
> -		release_resource(res);
> +	resource_list_for_each_entry_safe(entry, tentry, &info->resources) {
> +		res = entry->res;
> +		if (res->parent &&
> +		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
> +			release_resource(res);
> +		resource_list_destroy_entry(entry);
>   	}
>
> -	free_pci_root_info_res(info);
>   	kfree(info);
>   }
>
> @@ -373,99 +395,49 @@ static void release_pci_root_info(struct pci_host_bridge *bridge)
>   	__release_pci_root_info(info);
>   }
>
> -static int
> -probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
> -		int busnum, int domain)
> -{
> -	char *name;
> -
> -	name = kmalloc(16, GFP_KERNEL);
> -	if (!name)
> -		return -ENOMEM;
> -
> -	sprintf(name, "PCI Bus %04x:%02x", domain, busnum);
> -	info->bridge = device;
> -	info->name = name;
> -
> -	acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_window,
> -			&info->res_num);
> -	if (info->res_num) {
> -		info->res =
> -			kzalloc_node(sizeof(*info->res) * info->res_num,
> -				     GFP_KERNEL, info->controller->node);
> -		if (!info->res) {
> -			kfree(name);
> -			return -ENOMEM;
> -		}
> -
> -		info->res_offset =
> -			kzalloc_node(sizeof(*info->res_offset) * info->res_num,
> -					GFP_KERNEL, info->controller->node);
> -		if (!info->res_offset) {
> -			kfree(name);
> -			kfree(info->res);
> -			info->res = NULL;
> -			return -ENOMEM;
> -		}
> -
> -		info->res_num = 0;
> -		acpi_walk_resources(device->handle, METHOD_NAME__CRS,
> -			add_window, info);
> -	} else
> -		kfree(name);
> -
> -	return 0;
> -}
> -
>   struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>   {
>   	struct acpi_device *device = root->device;
>   	int domain = root->segment;
>   	int bus = root->secondary.start;
> -	struct pci_controller *controller;
> -	struct pci_root_info *info = NULL;
> -	int busnum = root->secondary.start;
> +	struct pci_root_info *info;
>   	struct pci_bus *pbus;
>   	int ret;
>
> -	controller = alloc_pci_controller(domain);
> -	if (!controller)
> -		return NULL;
> -
> -	controller->companion = device;
> -	controller->node = acpi_get_node(device->handle);
> -
>   	info = kzalloc(sizeof(*info), GFP_KERNEL);
>   	if (!info) {
>   		dev_err(&device->dev,
> -				"pci_bus %04x:%02x: ignored (out of memory)\n",
> -				domain, busnum);
> -		kfree(controller);
> +			"pci_bus %04x:%02x: ignored (out of memory)\n",
> +			domain, bus);
>   		return NULL;
>   	}
>
> -	info->controller = controller;
> -	INIT_LIST_HEAD(&info->io_resources);
> +	info->controller.segment = domain;
> +	info->controller.companion = device;
> +	info->controller.node = acpi_get_node(device->handle);
> +	info->bridge = device;
>   	INIT_LIST_HEAD(&info->resources);
> +	INIT_LIST_HEAD(&info->io_resources);
> +	snprintf(info->name, sizeof(info->name),
> +		 "PCI Bus %04x:%02x", domain, bus);
>
> -	ret = probe_pci_root_info(info, device, busnum, domain);
> -	if (ret) {
> -		kfree(info->controller);
> +	ret = probe_pci_root_info(info, device, bus, domain);
> +	if (ret <= 0) {
>   		kfree(info);
>   		return NULL;
>   	}
> -	/* insert busn resource at first */
> +	add_resources(info, &info->bridge->dev);
>   	pci_add_resource(&info->resources, &root->secondary);
> +
>   	/*
>   	 * See arch/x86/pci/acpi.c.
>   	 * The desired pci bus might already be scanned in a quirk. We
>   	 * should handle the case here, but it appears that IA64 hasn't
>   	 * such quirk. So we just ignore the case now.
>   	 */
> -	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops, controller,
> -				   &info->resources);
> +	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops,
> +				   &info->controller, &info->resources);
>   	if (!pbus) {
> -		pci_free_resource_list(&info->resources);
>   		__release_pci_root_info(info);
>   		return NULL;
>   	}
>