[PATCH V7 2/7] PCI: Apply the new generic I/O management on PCI IO hosts

[zhichang.yuan]

After introducing the new generic I/O space management(LIBIO), the original PCI
MMIO relevant helpers need to be updated based on the new interfaces defined in
LIBIO.
This patch adapts the corresponding code to match the changes introduced by
LIBIO.

Signed-off-by: zhichang.yuan <yuanzhichang@xxxxxxxxxxxxx>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@xxxxxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>        #earlier draft
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>       #drivers/pci parts
---
 drivers/acpi/pci_root.c |  8 +++--
 drivers/of/address.c    |  4 ++-
 drivers/pci/pci.c       | 96 +++++++++++--------------------------------------
 include/linux/pci.h     |  3 +-
 4 files changed, 30 insertions(+), 81 deletions(-)

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 919be0a..4d8cc24 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -730,7 +730,8 @@ static void acpi_pci_root_validate_resources(struct device *dev,
 	}
 }
 
-static void acpi_pci_root_remap_iospace(struct resource_entry *entry)
+static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
+			struct resource_entry *entry)
 {
 #ifdef PCI_IOBASE
 	struct resource *res = entry->res;
@@ -739,7 +740,7 @@ static void acpi_pci_root_remap_iospace(struct resource_entry *entry)
 	resource_size_t length = resource_size(res);
 	unsigned long port;
 
-	if (pci_register_io_range(cpu_addr, length))
+	if (pci_register_io_range(fwnode, cpu_addr, length))
 		goto err;
 
 	port = pci_address_to_pio(cpu_addr);
@@ -781,7 +782,8 @@ int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 	else {
 		resource_list_for_each_entry_safe(entry, tmp, list) {
 			if (entry->res->flags & IORESOURCE_IO)
-				acpi_pci_root_remap_iospace(entry);
+				acpi_pci_root_remap_iospace(&device->fwnode,
+						entry);
 
 			if (entry->res->flags & IORESOURCE_DISABLED)
 				resource_list_destroy_entry(entry);
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 02b2903..fb5d16a 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -2,6 +2,7 @@
 #define pr_fmt(fmt)	"OF: " fmt
 
 #include <linux/device.h>
+#include <linux/fwnode.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
@@ -323,7 +324,8 @@ int of_pci_range_to_resource(struct of_pci_range *range,
 
 	if (res->flags & IORESOURCE_IO) {
 		unsigned long port;
-		err = pci_register_io_range(range->cpu_addr, range->size);
+		err = pci_register_io_range(&np->fwnode, range->cpu_addr,
+				range->size);
 		if (err)
 			goto invalid_range;
 		port = pci_address_to_pio(range->cpu_addr);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7904d02..079319f 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3238,65 +3238,37 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
 }
 EXPORT_SYMBOL(pci_request_regions_exclusive);
 
-#ifdef PCI_IOBASE
-struct io_range {
-	struct list_head list;
-	phys_addr_t start;
-	resource_size_t size;
-};
-
-static LIST_HEAD(io_range_list);
-static DEFINE_SPINLOCK(io_range_lock);
-#endif
-
 /*
  * Record the PCI IO range (expressed as CPU physical address + size).
  * Return a negative value if an error has occured, zero otherwise
  */
-int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
+int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr,
+			resource_size_t	size)
 {
 	int err = 0;
 
 #ifdef PCI_IOBASE
-	struct io_range *range;
-	resource_size_t allocated_size = 0;
-
-	/* check if the range hasn't been previously recorded */
-	spin_lock(&io_range_lock);
-	list_for_each_entry(range, &io_range_list, list) {
-		if (addr >= range->start && addr + size <= range->start + size) {
-			/* range already registered, bail out */
-			goto end_register;
-		}
-		allocated_size += range->size;
-	}
-
-	/* range not registed yet, check for available space */
-	if (allocated_size + size - 1 > IO_SPACE_LIMIT) {
-		/* if it's too big check if 64K space can be reserved */
-		if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) {
-			err = -E2BIG;
-			goto end_register;
-		}
+	struct libio_range *range, *tmprange;
 
-		size = SZ_64K;
-		pr_warn("Requested IO range too big, new size set to 64K\n");
-	}
+	if (!size || addr + size < addr)
+		return -EINVAL;
 
-	/* add the range to the list */
-	range = kzalloc(sizeof(*range), GFP_ATOMIC);
-	if (!range) {
-		err = -ENOMEM;
-		goto end_register;
-	}
+	WARN_ON(!PAGE_ALIGNED(addr) || !PAGE_ALIGNED(size));
 
-	range->start = addr;
+	range = kzalloc(sizeof(*range), GFP_KERNEL);
+	if (!range)
+		return -ENOMEM;
+	range->node = fwnode;
+	range->flags = IO_CPU_MMIO;
 	range->size = size;
+	range->hw_start = addr;
 
-	list_add_tail(&range->list, &io_range_list);
-
-end_register:
-	spin_unlock(&io_range_lock);
+	tmprange = register_libio_range(range);
+	if (tmprange != range) {
+		kfree(range);
+		if (!IS_ERR(tmprange))
+			err = 0;
+	}
 #endif
 
 	return err;
@@ -3307,21 +3279,10 @@ phys_addr_t pci_pio_to_address(unsigned long pio)
 	phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
 
 #ifdef PCI_IOBASE
-	struct io_range *range;
-	resource_size_t allocated_size = 0;
-
 	if (pio > IO_SPACE_LIMIT)
 		return address;
 
-	spin_lock(&io_range_lock);
-	list_for_each_entry(range, &io_range_list, list) {
-		if (pio >= allocated_size && pio < allocated_size + range->size) {
-			address = range->start + pio - allocated_size;
-			break;
-		}
-		allocated_size += range->size;
-	}
-	spin_unlock(&io_range_lock);
+	address = libio_to_hwaddr(pio);
 #endif
 
 	return address;
@@ -3330,25 +3291,8 @@ phys_addr_t pci_pio_to_address(unsigned long pio)
 unsigned long __weak pci_address_to_pio(phys_addr_t address)
 {
 #ifdef PCI_IOBASE
-	struct io_range *res;
-	resource_size_t offset = 0;
-	unsigned long addr = -1;
-
-	spin_lock(&io_range_lock);
-	list_for_each_entry(res, &io_range_list, list) {
-		if (address >= res->start && address < res->start + res->size) {
-			addr = address - res->start + offset;
-			break;
-		}
-		offset += res->size;
-	}
-	spin_unlock(&io_range_lock);
-
-	return addr;
+	return libio_translate_cpuaddr(address);
 #else
-	if (address > IO_SPACE_LIMIT)
-		return (unsigned long)-1;
-
 	return (unsigned long) address;
 #endif
 }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index eb3da1a..6401327 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1194,7 +1194,8 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
 			void *alignf_data);
 
 
-int pci_register_io_range(phys_addr_t addr, resource_size_t size);
+int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr,
+			resource_size_t size);
 unsigned long pci_address_to_pio(phys_addr_t addr);
 phys_addr_t pci_pio_to_address(unsigned long pio);
 int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
-- 
1.9.1