Subject: [PATCH v6 1/3] of/pci: Unify pci_process_bridge_OF_ranges from Microblaze and PowerPC

From: [email-masked] (Michal Simek)
Date: Mon, 15 Apr 2013 18:50:55 +0200

Hi Thomas and Andrew,

First of all I would recommend you to add your tree to 0-day testing
system where you can easily catch up compilation failures for
microblaze and others.

Getting this compilation failure:
drivers/of/of_pci.c: In function 'pci_process_bridge_OF_ranges':
drivers/of/of_pci.c:88:22: error: storage size of 'range' isn't known
drivers/of/of_pci.c:89:29: error: storage size of 'parser' isn't known
drivers/of/of_pci.c:96:2: error: implicit declaration of function 'of_pci_range_parser' [-Werror=implicit-function-declaration]
drivers/of/of_pci.c:100:2: error: implicit declaration of function 'for_each_of_pci_range' [-Werror=implicit-function-declaration]
drivers/of/of_pci.c:100:41: error: expected ';' before '{' token
drivers/of/of_pci.c:90:6: warning: unused variable 'res_type' [-Wunused-variable]
drivers/of/of_pci.c:89:29: warning: unused variable 'parser' [-Wunused-variable]
drivers/of/of_pci.c:88:22: warning: unused variable 'range' [-Wunused-variable]
drivers/of/of_pci.c:87:19: warning: unused variable 'res' [-Wunused-variable]
drivers/of/of_pci.c:86:21: warning: unused variable 'isa_mb' [-Wunused-variable]
drivers/of/of_pci.c:85:17: warning: unused variable 'isa_hole' [-Wunused-variable]
drivers/of/of_pci.c:85:6: warning: unused variable 'memno' [-Wunused-variable]

which is caused missing linux/of_addresss.h in of_pci.c.
PowerPC probably won't have this problem because you have this header in asm/prom.h
but based on the same comment it is better to add it directly to the files.

That's why please add this header to this patch.

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 3e428a1..f30887e 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -1,6 +1,7 @@
 #include <linux/kernel.h>
 #include <linux/export.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/of_pci.h>
 #include <asm/prom.h>

When you fix it:
Acked-by: Michal Simek <[email-masked]>

Thanks,
Michal

On 04/15/2013 02:57 PM, Thomas Petazzoni wrote:
> Michal, Ben,
> 
> Would you have some time to look at this patch and give your comments
> and/or ACK ? Since it touches the PowerPC and Microblaze core code, we
> need your agreement to merge this code, and quite a bit of code pending
> for 3.10 depends on this patch.
> 
> Rob, alternatively, could we imagine doing a different version of the
> 'of/pci: Provide support for parsing PCI DT ranges property' that
> introduces the new API only, leaving the PowerPC and Microblaze rework
> as follow-up efforts, so that all the PCIe drivers that depend on this
> patch can get in for 3.10 ? I'd find it pretty sad if the Marvell PCIe
> driver that has been worked on since 4+ months does not get into 3.10
> just because this patch cannot be merged.
> 
> Thanks!
> 
> Thomas
> 
> On Thu, 11 Apr 2013 16:26:07 +0100, Andrew Murray wrote:
>> The pci_process_bridge_OF_ranges function, used to parse the "ranges"
>> property of a PCI host device, is found in both Microblaze and PowerPC
>> architectures. These implementations are nearly identical. This patch
>> moves this common code to a common place.
>>
>> Signed-off-by: Andrew Murray <[email-masked]>
>> Signed-off-by: Liviu Dudau <[email-masked]>
>> Reviewed-by: Rob Herring <[email-masked]>
>> Tested-by: Thomas Petazzoni <[email-masked]>
>> ---
>>  arch/microblaze/include/asm/pci-bridge.h |    5 +-
>>  arch/microblaze/pci/pci-common.c         |  192 ----------------------------
>>  arch/powerpc/include/asm/pci-bridge.h    |    5 +-
>>  arch/powerpc/kernel/pci-common.c         |  192 ----------------------------
>>  drivers/of/of_pci.c                      |  200 ++++++++++++++++++++++++++++++
>>  include/linux/of_pci.h                   |    4 +
>>  6 files changed, 206 insertions(+), 392 deletions(-)
>>
>> diff --git a/arch/microblaze/include/asm/pci-bridge.h b/arch/microblaze/include/asm/pci-bridge.h
>> index cb5d397..5783cd6 100644
>> --- a/arch/microblaze/include/asm/pci-bridge.h
>> +++ b/arch/microblaze/include/asm/pci-bridge.h
>> @@ -10,6 +10,7 @@
>>  #include <linux/pci.h>
>>  #include <linux/list.h>
>>  #include <linux/ioport.h>
>> +#include <linux/of_pci.h>
>>  
>>  struct device_node;
>>  
>> @@ -132,10 +133,6 @@ extern void setup_indirect_pci(struct pci_controller *hose,
>>  extern struct pci_controller *pci_find_hose_for_OF_device(
>>  			struct device_node *node);
>>  
>> -/* Fill up host controller resources from the OF node */
>> -extern void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> -			struct device_node *dev, int primary);
>> -
>>  /* Allocate & free a PCI host bridge structure */
>>  extern struct pci_controller *pcibios_alloc_controller(struct device_node *dev);
>>  extern void pcibios_free_controller(struct pci_controller *phb);
>> diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
>> index 9ea521e..2735ad9 100644
>> --- a/arch/microblaze/pci/pci-common.c
>> +++ b/arch/microblaze/pci/pci-common.c
>> @@ -622,198 +622,6 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
>>  	*end = rsrc->end - offset;
>>  }
>>  
>> -/**
>> - * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
>> - * @hose: newly allocated pci_controller to be setup
>> - * @dev: device node of the host bridge
>> - * @primary: set if primary bus (32 bits only, soon to be deprecated)
>> - *
>> - * This function will parse the "ranges" property of a PCI host bridge device
>> - * node and setup the resource mapping of a pci controller based on its
>> - * content.
>> - *
>> - * Life would be boring if it wasn't for a few issues that we have to deal
>> - * with here:
>> - *
>> - *   - We can only cope with one IO space range and up to 3 Memory space
>> - *     ranges. However, some machines (thanks Apple !) tend to split their
>> - *     space into lots of small contiguous ranges. So we have to coalesce.
>> - *
>> - *   - We can only cope with all memory ranges having the same offset
>> - *     between CPU addresses and PCI addresses. Unfortunately, some bridges
>> - *     are setup for a large 1:1 mapping along with a small "window" which
>> - *     maps PCI address 0 to some arbitrary high address of the CPU space in
>> - *     order to give access to the ISA memory hole.
>> - *     The way out of here that I've chosen for now is to always set the
>> - *     offset based on the first resource found, then override it if we
>> - *     have a different offset and the previous was set by an ISA hole.
>> - *
>> - *   - Some busses have IO space not starting at 0, which causes trouble with
>> - *     the way we do our IO resource renumbering. The code somewhat deals with
>> - *     it for 64 bits but I would expect problems on 32 bits.
>> - *
>> - *   - Some 32 bits platforms such as 4xx can have physical space larger than
>> - *     32 bits so we need to use 64 bits values for the parsing
>> - */
>> -void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> -				  struct device_node *dev, int primary)
>> -{
>> -	const u32 *ranges;
>> -	int rlen;
>> -	int pna = of_n_addr_cells(dev);
>> -	int np = pna + 5;
>> -	int memno = 0, isa_hole = -1;
>> -	u32 pci_space;
>> -	unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
>> -	unsigned long long isa_mb = 0;
>> -	struct resource *res;
>> -
>> -	pr_info("PCI host bridge %s %s ranges:\n",
>> -	       dev->full_name, primary ? "(primary)" : "");
>> -
>> -	/* Get ranges property */
>> -	ranges = of_get_property(dev, "ranges", &rlen);
>> -	if (ranges == NULL)
>> -		return;
>> -
>> -	/* Parse it */
>> -	pr_debug("Parsing ranges property...\n");
>> -	while ((rlen -= np * 4) >= 0) {
>> -		/* Read next ranges element */
>> -		pci_space = ranges[0];
>> -		pci_addr = of_read_number(ranges + 1, 2);
>> -		cpu_addr = of_translate_address(dev, ranges + 3);
>> -		size = of_read_number(ranges + pna + 3, 2);
>> -
>> -		pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
>> -				pci_space, pci_addr);
>> -		pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
>> -					cpu_addr, size);
>> -
>> -		ranges += np;
>> -
>> -		/* If we failed translation or got a zero-sized region
>> -		 * (some FW try to feed us with non sensical zero sized regions
>> -		 * such as power3 which look like some kind of attempt
>> -		 * at exposing the VGA memory hole)
>> -		 */
>> -		if (cpu_addr == OF_BAD_ADDR || size == 0)
>> -			continue;
>> -
>> -		/* Now consume following elements while they are contiguous */
>> -		for (; rlen >= np * sizeof(u32);
>> -		     ranges += np, rlen -= np * 4) {
>> -			if (ranges[0] != pci_space)
>> -				break;
>> -			pci_next = of_read_number(ranges + 1, 2);
>> -			cpu_next = of_translate_address(dev, ranges + 3);
>> -			if (pci_next != pci_addr + size ||
>> -			    cpu_next != cpu_addr + size)
>> -				break;
>> -			size += of_read_number(ranges + pna + 3, 2);
>> -		}
>> -
>> -		/* Act based on address space type */
>> -		res = NULL;
>> -		switch ((pci_space >> 24) & 0x3) {
>> -		case 1:		/* PCI IO space */
>> -			pr_info("  IO 0x%016llx..0x%016llx -> 0x%016llx\n",
>> -			       cpu_addr, cpu_addr + size - 1, pci_addr);
>> -
>> -			/* We support only one IO range */
>> -			if (hose->pci_io_size) {
>> -				pr_info(" \\--> Skipped (too many) !\n");
>> -				continue;
>> -			}
>> -			/* On 32 bits, limit I/O space to 16MB */
>> -			if (size > 0x01000000)
>> -				size = 0x01000000;
>> -
>> -			/* 32 bits needs to map IOs here */
>> -			hose->io_base_virt = ioremap(cpu_addr, size);
>> -
>> -			/* Expect trouble if pci_addr is not 0 */
>> -			if (primary)
>> -				isa_io_base =
>> -					(unsigned long)hose->io_base_virt;
>> -			/* pci_io_size and io_base_phys always represent IO
>> -			 * space starting at 0 so we factor in pci_addr
>> -			 */
>> -			hose->pci_io_size = pci_addr + size;
>> -			hose->io_base_phys = cpu_addr - pci_addr;
>> -
>> -			/* Build resource */
>> -			res = &hose->io_resource;
>> -			res->flags = IORESOURCE_IO;
>> -			res->start = pci_addr;
>> -			break;
>> -		case 2:		/* PCI Memory space */
>> -		case 3:		/* PCI 64 bits Memory space */
>> -			pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
>> -			       cpu_addr, cpu_addr + size - 1, pci_addr,
>> -			       (pci_space & 0x40000000) ? "Prefetch" : "");
>> -
>> -			/* We support only 3 memory ranges */
>> -			if (memno >= 3) {
>> -				pr_info(" \\--> Skipped (too many) !\n");
>> -				continue;
>> -			}
>> -			/* Handles ISA memory hole space here */
>> -			if (pci_addr == 0) {
>> -				isa_mb = cpu_addr;
>> -				isa_hole = memno;
>> -				if (primary || isa_mem_base == 0)
>> -					isa_mem_base = cpu_addr;
>> -				hose->isa_mem_phys = cpu_addr;
>> -				hose->isa_mem_size = size;
>> -			}
>> -
>> -			/* We get the PCI/Mem offset from the first range or
>> -			 * the, current one if the offset came from an ISA
>> -			 * hole. If they don't match, bugger.
>> -			 */
>> -			if (memno == 0 ||
>> -			    (isa_hole >= 0 && pci_addr != 0 &&
>> -			     hose->pci_mem_offset == isa_mb))
>> -				hose->pci_mem_offset = cpu_addr - pci_addr;
>> -			else if (pci_addr != 0 &&
>> -				 hose->pci_mem_offset != cpu_addr - pci_addr) {
>> -				pr_info(" \\--> Skipped (offset mismatch) !\n");
>> -				continue;
>> -			}
>> -
>> -			/* Build resource */
>> -			res = &hose->mem_resources[memno++];
>> -			res->flags = IORESOURCE_MEM;
>> -			if (pci_space & 0x40000000)
>> -				res->flags |= IORESOURCE_PREFETCH;
>> -			res->start = cpu_addr;
>> -			break;
>> -		}
>> -		if (res != NULL) {
>> -			res->name = dev->full_name;
>> -			res->end = res->start + size - 1;
>> -			res->parent = NULL;
>> -			res->sibling = NULL;
>> -			res->child = NULL;
>> -		}
>> -	}
>> -
>> -	/* If there's an ISA hole and the pci_mem_offset is -not- matching
>> -	 * the ISA hole offset, then we need to remove the ISA hole from
>> -	 * the resource list for that brige
>> -	 */
>> -	if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
>> -		unsigned int next = isa_hole + 1;
>> -		pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
>> -		if (next < memno)
>> -			memmove(&hose->mem_resources[isa_hole],
>> -				&hose->mem_resources[next],
>> -				sizeof(struct resource) * (memno - next));
>> -		hose->mem_resources[--memno].flags = 0;
>> -	}
>> -}
>> -
>>  /* Decide whether to display the domain number in /proc */
>>  int pci_proc_domain(struct pci_bus *bus)
>>  {
>> diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
>> index 025a130..205bfba 100644
>> --- a/arch/powerpc/include/asm/pci-bridge.h
>> +++ b/arch/powerpc/include/asm/pci-bridge.h
>> @@ -10,6 +10,7 @@
>>  #include <linux/pci.h>
>>  #include <linux/list.h>
>>  #include <linux/ioport.h>
>> +#include <linux/of_pci.h>
>>  #include <asm-generic/pci-bridge.h>
>>  
>>  struct device_node;
>> @@ -231,10 +232,6 @@ extern int pcibios_map_io_space(struct pci_bus *bus);
>>  extern struct pci_controller *pci_find_hose_for_OF_device(
>>  			struct device_node* node);
>>  
>> -/* Fill up host controller resources from the OF node */
>> -extern void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> -			struct device_node *dev, int primary);
>> -
>>  /* Allocate & free a PCI host bridge structure */
>>  extern struct pci_controller *pcibios_alloc_controller(struct device_node *dev);
>>  extern void pcibios_free_controller(struct pci_controller *phb);
>> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
>> index fa12ae4..6edf396 100644
>> --- a/arch/powerpc/kernel/pci-common.c
>> +++ b/arch/powerpc/kernel/pci-common.c
>> @@ -640,198 +640,6 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
>>  	*end = rsrc->end - offset;
>>  }
>>  
>> -/**
>> - * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
>> - * @hose: newly allocated pci_controller to be setup
>> - * @dev: device node of the host bridge
>> - * @primary: set if primary bus (32 bits only, soon to be deprecated)
>> - *
>> - * This function will parse the "ranges" property of a PCI host bridge device
>> - * node and setup the resource mapping of a pci controller based on its
>> - * content.
>> - *
>> - * Life would be boring if it wasn't for a few issues that we have to deal
>> - * with here:
>> - *
>> - *   - We can only cope with one IO space range and up to 3 Memory space
>> - *     ranges. However, some machines (thanks Apple !) tend to split their
>> - *     space into lots of small contiguous ranges. So we have to coalesce.
>> - *
>> - *   - We can only cope with all memory ranges having the same offset
>> - *     between CPU addresses and PCI addresses. Unfortunately, some bridges
>> - *     are setup for a large 1:1 mapping along with a small "window" which
>> - *     maps PCI address 0 to some arbitrary high address of the CPU space in
>> - *     order to give access to the ISA memory hole.
>> - *     The way out of here that I've chosen for now is to always set the
>> - *     offset based on the first resource found, then override it if we
>> - *     have a different offset and the previous was set by an ISA hole.
>> - *
>> - *   - Some busses have IO space not starting at 0, which causes trouble with
>> - *     the way we do our IO resource renumbering. The code somewhat deals with
>> - *     it for 64 bits but I would expect problems on 32 bits.
>> - *
>> - *   - Some 32 bits platforms such as 4xx can have physical space larger than
>> - *     32 bits so we need to use 64 bits values for the parsing
>> - */
>> -void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> -				  struct device_node *dev, int primary)
>> -{
>> -	const u32 *ranges;
>> -	int rlen;
>> -	int pna = of_n_addr_cells(dev);
>> -	int np = pna + 5;
>> -	int memno = 0, isa_hole = -1;
>> -	u32 pci_space;
>> -	unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
>> -	unsigned long long isa_mb = 0;
>> -	struct resource *res;
>> -
>> -	printk(KERN_INFO "PCI host bridge %s %s ranges:\n",
>> -	       dev->full_name, primary ? "(primary)" : "");
>> -
>> -	/* Get ranges property */
>> -	ranges = of_get_property(dev, "ranges", &rlen);
>> -	if (ranges == NULL)
>> -		return;
>> -
>> -	/* Parse it */
>> -	while ((rlen -= np * 4) >= 0) {
>> -		/* Read next ranges element */
>> -		pci_space = ranges[0];
>> -		pci_addr = of_read_number(ranges + 1, 2);
>> -		cpu_addr = of_translate_address(dev, ranges + 3);
>> -		size = of_read_number(ranges + pna + 3, 2);
>> -		ranges += np;
>> -
>> -		/* If we failed translation or got a zero-sized region
>> -		 * (some FW try to feed us with non sensical zero sized regions
>> -		 * such as power3 which look like some kind of attempt at exposing
>> -		 * the VGA memory hole)
>> -		 */
>> -		if (cpu_addr == OF_BAD_ADDR || size == 0)
>> -			continue;
>> -
>> -		/* Now consume following elements while they are contiguous */
>> -		for (; rlen >= np * sizeof(u32);
>> -		     ranges += np, rlen -= np * 4) {
>> -			if (ranges[0] != pci_space)
>> -				break;
>> -			pci_next = of_read_number(ranges + 1, 2);
>> -			cpu_next = of_translate_address(dev, ranges + 3);
>> -			if (pci_next != pci_addr + size ||
>> -			    cpu_next != cpu_addr + size)
>> -				break;
>> -			size += of_read_number(ranges + pna + 3, 2);
>> -		}
>> -
>> -		/* Act based on address space type */
>> -		res = NULL;
>> -		switch ((pci_space >> 24) & 0x3) {
>> -		case 1:		/* PCI IO space */
>> -			printk(KERN_INFO
>> -			       "  IO 0x%016llx..0x%016llx -> 0x%016llx\n",
>> -			       cpu_addr, cpu_addr + size - 1, pci_addr);
>> -
>> -			/* We support only one IO range */
>> -			if (hose->pci_io_size) {
>> -				printk(KERN_INFO
>> -				       " \\--> Skipped (too many) !\n");
>> -				continue;
>> -			}
>> -#ifdef CONFIG_PPC32
>> -			/* On 32 bits, limit I/O space to 16MB */
>> -			if (size > 0x01000000)
>> -				size = 0x01000000;
>> -
>> -			/* 32 bits needs to map IOs here */
>> -			hose->io_base_virt = ioremap(cpu_addr, size);
>> -
>> -			/* Expect trouble if pci_addr is not 0 */
>> -			if (primary)
>> -				isa_io_base =
>> -					(unsigned long)hose->io_base_virt;
>> -#endif /* CONFIG_PPC32 */
>> -			/* pci_io_size and io_base_phys always represent IO
>> -			 * space starting at 0 so we factor in pci_addr
>> -			 */
>> -			hose->pci_io_size = pci_addr + size;
>> -			hose->io_base_phys = cpu_addr - pci_addr;
>> -
>> -			/* Build resource */
>> -			res = &hose->io_resource;
>> -			res->flags = IORESOURCE_IO;
>> -			res->start = pci_addr;
>> -			break;
>> -		case 2:		/* PCI Memory space */
>> -		case 3:		/* PCI 64 bits Memory space */
>> -			printk(KERN_INFO
>> -			       " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
>> -			       cpu_addr, cpu_addr + size - 1, pci_addr,
>> -			       (pci_space & 0x40000000) ? "Prefetch" : "");
>> -
>> -			/* We support only 3 memory ranges */
>> -			if (memno >= 3) {
>> -				printk(KERN_INFO
>> -				       " \\--> Skipped (too many) !\n");
>> -				continue;
>> -			}
>> -			/* Handles ISA memory hole space here */
>> -			if (pci_addr == 0) {
>> -				isa_mb = cpu_addr;
>> -				isa_hole = memno;
>> -				if (primary || isa_mem_base == 0)
>> -					isa_mem_base = cpu_addr;
>> -				hose->isa_mem_phys = cpu_addr;
>> -				hose->isa_mem_size = size;
>> -			}
>> -
>> -			/* We get the PCI/Mem offset from the first range or
>> -			 * the, current one if the offset came from an ISA
>> -			 * hole. If they don't match, bugger.
>> -			 */
>> -			if (memno == 0 ||
>> -			    (isa_hole >= 0 && pci_addr != 0 &&
>> -			     hose->pci_mem_offset == isa_mb))
>> -				hose->pci_mem_offset = cpu_addr - pci_addr;
>> -			else if (pci_addr != 0 &&
>> -				 hose->pci_mem_offset != cpu_addr - pci_addr) {
>> -				printk(KERN_INFO
>> -				       " \\--> Skipped (offset mismatch) !\n");
>> -				continue;
>> -			}
>> -
>> -			/* Build resource */
>> -			res = &hose->mem_resources[memno++];
>> -			res->flags = IORESOURCE_MEM;
>> -			if (pci_space & 0x40000000)
>> -				res->flags |= IORESOURCE_PREFETCH;
>> -			res->start = cpu_addr;
>> -			break;
>> -		}
>> -		if (res != NULL) {
>> -			res->name = dev->full_name;
>> -			res->end = res->start + size - 1;
>> -			res->parent = NULL;
>> -			res->sibling = NULL;
>> -			res->child = NULL;
>> -		}
>> -	}
>> -
>> -	/* If there's an ISA hole and the pci_mem_offset is -not- matching
>> -	 * the ISA hole offset, then we need to remove the ISA hole from
>> -	 * the resource list for that brige
>> -	 */
>> -	if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
>> -		unsigned int next = isa_hole + 1;
>> -		printk(KERN_INFO " Removing ISA hole at 0x%016llx\n", isa_mb);
>> -		if (next < memno)
>> -			memmove(&hose->mem_resources[isa_hole],
>> -				&hose->mem_resources[next],
>> -				sizeof(struct resource) * (memno - next));
>> -		hose->mem_resources[--memno].flags = 0;
>> -	}
>> -}
>> -
>>  /* Decide whether to display the domain number in /proc */
>>  int pci_proc_domain(struct pci_bus *bus)
>>  {
>> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
>> index 13e37e2..1626172 100644
>> --- a/drivers/of/of_pci.c
>> +++ b/drivers/of/of_pci.c
>> @@ -4,6 +4,10 @@
>>  #include <linux/of_pci.h>
>>  #include <asm/prom.h>
>>  
>> +#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
>> +#include <asm/pci-bridge.h>
>> +#endif
>> +
>>  static inline int __of_pci_pci_compare(struct device_node *node,
>>  				       unsigned int devfn)
>>  {
>> @@ -40,3 +44,199 @@ struct device_node *of_pci_find_child_device(struct device_node *parent,
>>  	return NULL;
>>  }
>>  EXPORT_SYMBOL_GPL(of_pci_find_child_device);
>> +
>> +/**
>> + * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
>> + * @hose: newly allocated pci_controller to be setup
>> + * @dev: device node of the host bridge
>> + * @primary: set if primary bus (32 bits only, soon to be deprecated)
>> + *
>> + * This function will parse the "ranges" property of a PCI host bridge device
>> + * node and setup the resource mapping of a pci controller based on its
>> + * content.
>> + *
>> + * Life would be boring if it wasn't for a few issues that we have to deal
>> + * with here:
>> + *
>> + *   - We can only cope with one IO space range and up to 3 Memory space
>> + *     ranges. However, some machines (thanks Apple !) tend to split their
>> + *     space into lots of small contiguous ranges. So we have to coalesce.
>> + *
>> + *   - We can only cope with all memory ranges having the same offset
>> + *     between CPU addresses and PCI addresses. Unfortunately, some bridges
>> + *     are setup for a large 1:1 mapping along with a small "window" which
>> + *     maps PCI address 0 to some arbitrary high address of the CPU space in
>> + *     order to give access to the ISA memory hole.
>> + *     The way out of here that I've chosen for now is to always set the
>> + *     offset based on the first resource found, then override it if we
>> + *     have a different offset and the previous was set by an ISA hole.
>> + *
>> + *   - Some busses have IO space not starting at 0, which causes trouble with
>> + *     the way we do our IO resource renumbering. The code somewhat deals with
>> + *     it for 64 bits but I would expect problems on 32 bits.
>> + *
>> + *   - Some 32 bits platforms such as 4xx can have physical space larger than
>> + *     32 bits so we need to use 64 bits values for the parsing
>> + */
>> +#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
>> +void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> +				  struct device_node *dev, int primary)
>> +{
>> +	const u32 *ranges;
>> +	int rlen;
>> +	int pna = of_n_addr_cells(dev);
>> +	int np = pna + 5;
>> +	int memno = 0, isa_hole = -1;
>> +	u32 pci_space;
>> +	unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
>> +	unsigned long long isa_mb = 0;
>> +	struct resource *res;
>> +
>> +	pr_info("PCI host bridge %s %s ranges:\n",
>> +	       dev->full_name, primary ? "(primary)" : "");
>> +
>> +	/* Get ranges property */
>> +	ranges = of_get_property(dev, "ranges", &rlen);
>> +	if (ranges == NULL)
>> +		return;
>> +
>> +	/* Parse it */
>> +	pr_debug("Parsing ranges property...\n");
>> +	while ((rlen -= np * 4) >= 0) {
>> +		/* Read next ranges element */
>> +		pci_space = ranges[0];
>> +		pci_addr = of_read_number(ranges + 1, 2);
>> +		cpu_addr = of_translate_address(dev, ranges + 3);
>> +		size = of_read_number(ranges + pna + 3, 2);
>> +
>> +		pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
>> +				pci_space, pci_addr);
>> +		pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
>> +					cpu_addr, size);
>> +
>> +		ranges += np;
>> +
>> +		/* If we failed translation or got a zero-sized region
>> +		 * (some FW try to feed us with non sensical zero sized regions
>> +		 * such as power3 which look like some kind of attempt
>> +		 * at exposing the VGA memory hole)
>> +		 */
>> +		if (cpu_addr == OF_BAD_ADDR || size == 0)
>> +			continue;
>> +
>> +		/* Now consume following elements while they are contiguous */
>> +		for (; rlen >= np * sizeof(u32);
>> +		     ranges += np, rlen -= np * 4) {
>> +			if (ranges[0] != pci_space)
>> +				break;
>> +			pci_next = of_read_number(ranges + 1, 2);
>> +			cpu_next = of_translate_address(dev, ranges + 3);
>> +			if (pci_next != pci_addr + size ||
>> +			    cpu_next != cpu_addr + size)
>> +				break;
>> +			size += of_read_number(ranges + pna + 3, 2);
>> +		}
>> +
>> +		/* Act based on address space type */
>> +		res = NULL;
>> +		switch ((pci_space >> 24) & 0x3) {
>> +		case 1:		/* PCI IO space */
>> +			pr_info("  IO 0x%016llx..0x%016llx -> 0x%016llx\n",
>> +			       cpu_addr, cpu_addr + size - 1, pci_addr);
>> +
>> +			/* We support only one IO range */
>> +			if (hose->pci_io_size) {
>> +				pr_info(" \\--> Skipped (too many) !\n");
>> +				continue;
>> +			}
>> +#if (!IS_ENABLED(CONFIG_64BIT))
>> +			/* On 32 bits, limit I/O space to 16MB */
>> +			if (size > 0x01000000)
>> +				size = 0x01000000;
>> +
>> +			/* 32 bits needs to map IOs here */
>> +			hose->io_base_virt = ioremap(cpu_addr, size);
>> +
>> +			/* Expect trouble if pci_addr is not 0 */
>> +			if (primary)
>> +				isa_io_base =
>> +					(unsigned long)hose->io_base_virt;
>> +#endif /* !CONFIG_64BIT */
>> +			/* pci_io_size and io_base_phys always represent IO
>> +			 * space starting at 0 so we factor in pci_addr
>> +			 */
>> +			hose->pci_io_size = pci_addr + size;
>> +			hose->io_base_phys = cpu_addr - pci_addr;
>> +
>> +			/* Build resource */
>> +			res = &hose->io_resource;
>> +			res->flags = IORESOURCE_IO;
>> +			res->start = pci_addr;
>> +			break;
>> +		case 2:		/* PCI Memory space */
>> +		case 3:		/* PCI 64 bits Memory space */
>> +			pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
>> +			       cpu_addr, cpu_addr + size - 1, pci_addr,
>> +			       (pci_space & 0x40000000) ? "Prefetch" : "");
>> +
>> +			/* We support only 3 memory ranges */
>> +			if (memno >= 3) {
>> +				pr_info(" \\--> Skipped (too many) !\n");
>> +				continue;
>> +			}
>> +			/* Handles ISA memory hole space here */
>> +			if (pci_addr == 0) {
>> +				isa_mb = cpu_addr;
>> +				isa_hole = memno;
>> +				if (primary || isa_mem_base == 0)
>> +					isa_mem_base = cpu_addr;
>> +				hose->isa_mem_phys = cpu_addr;
>> +				hose->isa_mem_size = size;
>> +			}
>> +
>> +			/* We get the PCI/Mem offset from the first range or
>> +			 * the, current one if the offset came from an ISA
>> +			 * hole. If they don't match, bugger.
>> +			 */
>> +			if (memno == 0 ||
>> +			    (isa_hole >= 0 && pci_addr != 0 &&
>> +			     hose->pci_mem_offset == isa_mb))
>> +				hose->pci_mem_offset = cpu_addr - pci_addr;
>> +			else if (pci_addr != 0 &&
>> +				 hose->pci_mem_offset != cpu_addr - pci_addr) {
>> +				pr_info(" \\--> Skipped (offset mismatch) !\n");
>> +				continue;
>> +			}
>> +
>> +			/* Build resource */
>> +			res = &hose->mem_resources[memno++];
>> +			res->flags = IORESOURCE_MEM;
>> +			if (pci_space & 0x40000000)
>> +				res->flags |= IORESOURCE_PREFETCH;
>> +			res->start = cpu_addr;
>> +			break;
>> +		}
>> +		if (res != NULL) {
>> +			res->name = dev->full_name;
>> +			res->end = res->start + size - 1;
>> +			res->parent = NULL;
>> +			res->sibling = NULL;
>> +			res->child = NULL;
>> +		}
>> +	}
>> +
>> +	/* If there's an ISA hole and the pci_mem_offset is -not- matching
>> +	 * the ISA hole offset, then we need to remove the ISA hole from
>> +	 * the resource list for that brige
>> +	 */
>> +	if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
>> +		unsigned int next = isa_hole + 1;
>> +		pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
>> +		if (next < memno)
>> +			memmove(&hose->mem_resources[isa_hole],
>> +				&hose->mem_resources[next],
>> +				sizeof(struct resource) * (memno - next));
>> +		hose->mem_resources[--memno].flags = 0;
>> +	}
>> +}
>> +#endif
>> diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
>> index bb115de..33e8ead 100644
>> --- a/include/linux/of_pci.h
>> +++ b/include/linux/of_pci.h
>> @@ -11,4 +11,8 @@ struct device_node;
>>  struct device_node *of_pci_find_child_device(struct device_node *parent,
>>  					     unsigned int devfn);
>>  
>> +struct pci_controller;
>> +void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> +			struct device_node *dev, int primary);
>> +
>>  #endif
> 
> 
> 

-- 
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID:
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/
Maintainer of Linux kernel - Xilinx Zynq ARM architecture
Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform