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linux-next/drivers/of/of_pci_irq.c

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pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
#include <linux/kernel.h>
#include <linux/of_pci.h>
#include <linux/of_irq.h>
drivers/of: include export.h for EXPORT_SYMBOL_GPL/THIS_MODULE as required For files that were getting these macros via the implicit presence of module.h being everywhere. With contributions from Stephen Rothwell <sfr@canb.auug.org.au>. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-07-29 14:05:38 +08:00
#include <linux/export.h>
pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
/**
of/irq: Rename of_irq_map_* functions to of_irq_parse_* The OF irq handling code has been overloading the term 'map' to refer to both parsing the data in the device tree and mapping it to the internal linux irq system. This is probably because the device tree does have the concept of an 'interrupt-map' function for translating interrupt references from one node to another, but 'map' is still confusing when the primary purpose of some of the functions are to parse the DT data. This patch renames all the of_irq_map_* functions to of_irq_parse_* which makes it clear that there is a difference between the parsing phase and the mapping phase. Kernel code can make use of just the parsing or just the mapping support as needed by the subsystem. The patch was generated mechanically with a handful of sed commands. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Tony Lindgren <tony@atomide.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-20 00:22:36 +08:00
* of_irq_parse_pci - Resolve the interrupt for a PCI device
pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
* @pdev: the device whose interrupt is to be resolved
* @out_irq: structure of_irq filled by this function
*
* This function resolves the PCI interrupt for a given PCI device. If a
* device-node exists for a given pci_dev, it will use normal OF tree
* walking. If not, it will implement standard swizzling and walk up the
* PCI tree until an device-node is found, at which point it will finish
* resolving using the OF tree walking.
*/
of/irq: Replace of_irq with of_phandle_args struct of_irq and struct of_phandle_args are exactly the same structure. This patch makes the kernel use of_phandle_args everywhere. This in itself isn't a big deal, but it makes some follow-on patches simpler. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Tony Lindgren <tony@atomide.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-15 23:39:11 +08:00
int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
{
struct device_node *dn, *ppnode;
struct pci_dev *ppdev;
u32 lspec;
__be32 lspec_be;
__be32 laddr[3];
u8 pin;
int rc;
/* Check if we have a device node, if yes, fallback to standard
* device tree parsing
*/
dn = pci_device_to_OF_node(pdev);
if (dn) {
of/irq: Rename of_irq_map_* functions to of_irq_parse_* The OF irq handling code has been overloading the term 'map' to refer to both parsing the data in the device tree and mapping it to the internal linux irq system. This is probably because the device tree does have the concept of an 'interrupt-map' function for translating interrupt references from one node to another, but 'map' is still confusing when the primary purpose of some of the functions are to parse the DT data. This patch renames all the of_irq_map_* functions to of_irq_parse_* which makes it clear that there is a difference between the parsing phase and the mapping phase. Kernel code can make use of just the parsing or just the mapping support as needed by the subsystem. The patch was generated mechanically with a handful of sed commands. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Tony Lindgren <tony@atomide.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-20 00:22:36 +08:00
rc = of_irq_parse_one(dn, 0, out_irq);
pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
if (!rc)
return rc;
}
/* Ok, we don't, time to have fun. Let's start by building up an
* interrupt spec. we assume #interrupt-cells is 1, which is standard
* for PCI. If you do different, then don't use that routine.
*/
rc = pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin);
if (rc != 0)
return rc;
/* No pin, exit */
if (pin == 0)
return -ENODEV;
/* Now we walk up the PCI tree */
lspec = pin;
for (;;) {
/* Get the pci_dev of our parent */
ppdev = pdev->bus->self;
/* Ouch, it's a host bridge... */
if (ppdev == NULL) {
ppnode = pci_bus_to_OF_node(pdev->bus);
/* No node for host bridge ? give up */
if (ppnode == NULL)
return -EINVAL;
} else {
/* We found a P2P bridge, check if it has a node */
ppnode = pci_device_to_OF_node(ppdev);
}
/* Ok, we have found a parent with a device-node, hand over to
* the OF parsing code.
* We build a unit address from the linux device to be used for
* resolution. Note that we use the linux bus number which may
* not match your firmware bus numbering.
* Fortunately, in most cases, interrupt-map-mask doesn't
* include the bus number as part of the matching.
* You should still be careful about that though if you intend
* to rely on this function (you ship a firmware that doesn't
* create device nodes for all PCI devices).
*/
if (ppnode)
break;
/* We can only get here if we hit a P2P bridge with no node,
* let's do standard swizzling and try again
*/
lspec = pci_swizzle_interrupt_pin(pdev, lspec);
pdev = ppdev;
}
of/irq: Refactor interrupt-map parsing All the users of of_irq_parse_raw pass in a raw interrupt specifier from the device tree and expect it to be returned (possibly modified) in an of_phandle_args structure. However, the primary function of of_irq_parse_raw() is to check for translations due to the presence of one or more interrupt-map properties. The actual placing of the data into an of_phandle_args structure is trivial. If it is refactored to accept an of_phandle_args structure directly, then it becomes possible to consume of_phandle_args from other sources. This is important for an upcoming patch that allows a device to be connected to more than one interrupt parent. It also simplifies the code a bit. The biggest complication with this patch is that the old version works on the interrupt specifiers in __be32 form, but the of_phandle_args structure is intended to carry it in the cpu-native version. A bit of churn was required to make this work. In the end it results in tighter code, so the churn is worth it. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Tony Lindgren <tony@atomide.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-16 05:32:39 +08:00
out_irq->np = ppnode;
out_irq->args_count = 1;
out_irq->args[0] = lspec;
pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
lspec_be = cpu_to_be32(lspec);
laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
of/irq: Refactor interrupt-map parsing All the users of of_irq_parse_raw pass in a raw interrupt specifier from the device tree and expect it to be returned (possibly modified) in an of_phandle_args structure. However, the primary function of of_irq_parse_raw() is to check for translations due to the presence of one or more interrupt-map properties. The actual placing of the data into an of_phandle_args structure is trivial. If it is refactored to accept an of_phandle_args structure directly, then it becomes possible to consume of_phandle_args from other sources. This is important for an upcoming patch that allows a device to be connected to more than one interrupt parent. It also simplifies the code a bit. The biggest complication with this patch is that the old version works on the interrupt specifiers in __be32 form, but the of_phandle_args structure is intended to carry it in the cpu-native version. A bit of churn was required to make this work. In the end it results in tighter code, so the churn is worth it. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Tony Lindgren <tony@atomide.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-16 05:32:39 +08:00
laddr[1] = laddr[2] = cpu_to_be32(0);
return of_irq_parse_raw(laddr, out_irq);
pci/of: Match PCI devices to OF nodes dynamically powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:37:07 +08:00
}
of/irq: Rename of_irq_map_* functions to of_irq_parse_* The OF irq handling code has been overloading the term 'map' to refer to both parsing the data in the device tree and mapping it to the internal linux irq system. This is probably because the device tree does have the concept of an 'interrupt-map' function for translating interrupt references from one node to another, but 'map' is still confusing when the primary purpose of some of the functions are to parse the DT data. This patch renames all the of_irq_map_* functions to of_irq_parse_* which makes it clear that there is a difference between the parsing phase and the mapping phase. Kernel code can make use of just the parsing or just the mapping support as needed by the subsystem. The patch was generated mechanically with a handful of sed commands. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Tony Lindgren <tony@atomide.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-20 00:22:36 +08:00
EXPORT_SYMBOL_GPL(of_irq_parse_pci);
of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code. Several architectures open code effectively the same code block for finding and mapping PCI irqs. This patch consolidates it down to a single function. Signed-off-by: Grant Likely <grant.likely@linaro.org> Acked-by: Michal Simek <monstr@monstr.eu> Cc: Russell King <linux@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-20 05:44:55 +08:00
/**
* of_irq_parse_and_map_pci() - Decode a PCI irq from the device tree and map to a virq
* @dev: The pci device needing an irq
* @slot: PCI slot number; passed when used as map_irq callback. Unused
* @pin: PCI irq pin number; passed when used as map_irq callback. Unused
*
* @slot and @pin are unused, but included in the function so that this
* function can be used directly as the map_irq callback to pci_fixup_irqs().
*/
int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin)
{
struct of_phandle_args oirq;
int ret;
ret = of_irq_parse_pci(dev, &oirq);
if (ret) {
dev_err(&dev->dev, "of_irq_parse_pci() failed with rc=%d\n", ret);
return 0; /* Proper return code 0 == NO_IRQ */
}
return irq_create_of_mapping(&oirq);
}
EXPORT_SYMBOL_GPL(of_irq_parse_and_map_pci);
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