| Message ID | 1411003825-21521-8-git-send-email-Liviu.Dudau@arm.com |
|---|---|
| State | Changes Requested |
| Headers | show |
On Thu, Sep 18, 2014 at 02:30:22AM +0100, Liviu Dudau wrote: > Add of_pci_get_domain_nr() to retrieve the PCI domain number > of a given device from DT. If the information is not present, > the function can be requested to allocate a new domain number. Is of_pci_get_domain_nr() used somewhere? If the use is in some future series, please mention it explicitly. I'm just trying to avoid merging unused code. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday 18 September 2014, Liviu Dudau wrote: > > Add of_pci_get_domain_nr() to retrieve the PCI domain number > of a given device from DT. If the information is not present, > the function can be requested to allocate a new domain number. > > Cc: Bjorn Helgaas <bhelgaas@google.com> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> This is more elaborate than I remember it, and while the simpler version (which potentially resulted in a conflict for inconsistent DTs) was fine, this one also seems ok. Acked-by: Arnd Bergmann <arnd@arndb.de> -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/17/2014 08:30 PM, Liviu Dudau wrote: > Add of_pci_get_domain_nr() to retrieve the PCI domain number > of a given device from DT. If the information is not present, > the function can be requested to allocate a new domain number. > > Cc: Bjorn Helgaas <bhelgaas@google.com> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > --- [...] > +/** > + * This function will try to obtain the host bridge domain number by > + * using of_alias_get_id() call with "pci-domain" as a stem. If that > + * fails, a local allocator will be used. The local allocator can > + * be requested to return a new domain_nr if the information is missing > + * from the device tree. > + * > + * @node: device tree node with the domain information > + * @allocate_if_missing: if DT lacks information about the domain nr, > + * allocate a new number. > + * > + * Returns the associated domain number from DT, or a new domain number > + * if DT information is missing and @allocate_if_missing is true. If > + * @allocate_if_missing is false then the last allocated domain number > + * will be returned. > + */ > +int of_pci_get_domain_nr(struct device_node *node, bool allocate_if_missing) > +{ > + int domain; > + > + domain = atomic_read(&of_domain_nr); > + if (domain == -1) { > + /* first run, get max defined domain nr in device tree */ > + domain = of_get_max_pci_domain_nr(); > + /* then set the start value for allocator to be max + 1 */ > + atomic_set(&of_domain_nr, domain + 1); atomic_read followed by atomic_set is not an atomic operation. As I previously said, I don't like how this function is a mixture of data retrieval and domian # allocation. I think we need 2 functions. > + } > + domain = of_alias_get_id(node, "pci-domain"); I still do not like using aliases here. Just put pci-domain or linux,pci-domain into the PCI node. I think we should assume all PCI root buses either have a domain property or they don't and a mixture is an error. I'm not sure if that simplifies the code or not though. In the interest of merging, I think you should just do a simple allocation and add the DT domain handling as a second step. You will also need to document the DT part. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Sep 19, 2014 at 10:03:13PM +0100, Bjorn Helgaas wrote: > On Thu, Sep 18, 2014 at 02:30:22AM +0100, Liviu Dudau wrote: > > Add of_pci_get_domain_nr() to retrieve the PCI domain number > > of a given device from DT. If the information is not present, > > the function can be requested to allocate a new domain number. > > Is of_pci_get_domain_nr() used somewhere? If the use is in some future > series, please mention it explicitly. I'm just trying to avoid merging > unused code. It is used in the arm64 specific patch that I have dropped out of my pull request. After discussions with Catalin I will add the patch back into the tree that you've pulled from as he is OK with your tree carrying the whole package. I need to ask for some guidance here: for addressing some of your comments and Rob's I can add more patches in my v11 branch and you can pull them when you think they are ready. But one of your comments was requesting splitting a patch into two blocks - one that moves of_pci_range_to_resource() into drivers/of/address.c and one that fixes it's behaviour - and I don't know how you would like that handled. Should I revert the original patch and add the new ones, or should I rebase the whole series into a different branch that you can pull from? Best regards, Liviu > > Bjorn >
On Sat, Sep 20, 2014 at 03:24:20AM +0100, Arnd Bergmann wrote: > On Thursday 18 September 2014, Liviu Dudau wrote: > > > > Add of_pci_get_domain_nr() to retrieve the PCI domain number > > of a given device from DT. If the information is not present, > > the function can be requested to allocate a new domain number. > > > > Cc: Bjorn Helgaas <bhelgaas@google.com> > > Cc: Arnd Bergmann <arnd@arndb.de> > > Cc: Grant Likely <grant.likely@linaro.org> > > Cc: Rob Herring <robh+dt@kernel.org> > > Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> > > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > > This is more elaborate than I remember it, and while the simpler > version (which potentially resulted in a conflict for inconsistent > DTs) was fine, this one also seems ok. > > Acked-by: Arnd Bergmann <arnd@arndb.de> Thanks Arnd! Best regards, Liviu > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
On Mon, Sep 22, 2014 at 5:05 AM, Liviu Dudau <Liviu.Dudau@arm.com> wrote: > On Fri, Sep 19, 2014 at 10:03:13PM +0100, Bjorn Helgaas wrote: >> On Thu, Sep 18, 2014 at 02:30:22AM +0100, Liviu Dudau wrote: >> > Add of_pci_get_domain_nr() to retrieve the PCI domain number >> > of a given device from DT. If the information is not present, >> > the function can be requested to allocate a new domain number. >> >> Is of_pci_get_domain_nr() used somewhere? If the use is in some future >> series, please mention it explicitly. I'm just trying to avoid merging >> unused code. > > It is used in the arm64 specific patch that I have dropped out of my > pull request. After discussions with Catalin I will add the patch back > into the tree that you've pulled from as he is OK with your tree carrying > the whole package. > > I need to ask for some guidance here: for addressing some of your comments > and Rob's I can add more patches in my v11 branch and you can pull them > when you think they are ready. But one of your comments was requesting > splitting a patch into two blocks - one that moves of_pci_range_to_resource() > into drivers/of/address.c and one that fixes it's behaviour - and I don't > know how you would like that handled. Should I revert the original patch > and add the new ones, or should I rebase the whole series into a different > branch that you can pull from? I guess the easiest thing is probably just to send a v12 series. I was hoping we were close enough for me to just hand-integrate minor tweaks into my branch, but I think that will just create more confusion. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Sep 22, 2014 at 04:25:13PM +0100, Bjorn Helgaas wrote: > On Mon, Sep 22, 2014 at 5:05 AM, Liviu Dudau <Liviu.Dudau@arm.com> wrote: > > On Fri, Sep 19, 2014 at 10:03:13PM +0100, Bjorn Helgaas wrote: > >> On Thu, Sep 18, 2014 at 02:30:22AM +0100, Liviu Dudau wrote: > >> > Add of_pci_get_domain_nr() to retrieve the PCI domain number > >> > of a given device from DT. If the information is not present, > >> > the function can be requested to allocate a new domain number. > >> > >> Is of_pci_get_domain_nr() used somewhere? If the use is in some future > >> series, please mention it explicitly. I'm just trying to avoid merging > >> unused code. > > > > It is used in the arm64 specific patch that I have dropped out of my > > pull request. After discussions with Catalin I will add the patch back > > into the tree that you've pulled from as he is OK with your tree carrying > > the whole package. > > > > I need to ask for some guidance here: for addressing some of your comments > > and Rob's I can add more patches in my v11 branch and you can pull them > > when you think they are ready. But one of your comments was requesting > > splitting a patch into two blocks - one that moves of_pci_range_to_resource() > > into drivers/of/address.c and one that fixes it's behaviour - and I don't > > know how you would like that handled. Should I revert the original patch > > and add the new ones, or should I rebase the whole series into a different > > branch that you can pull from? > > I guess the easiest thing is probably just to send a v12 series. I > was hoping we were close enough for me to just hand-integrate minor > tweaks into my branch, but I think that will just create more > confusion. OK, I will send v12 then with all the acquired ACKs and fixes. Best regards, Liviu > > Bjorn >
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 8481996..7eaeac2 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -3,6 +3,8 @@ #include <linux/of.h> #include <linux/of_pci.h> +#include "of_private.h" + static inline int __of_pci_pci_compare(struct device_node *node, unsigned int data) { @@ -89,6 +91,66 @@ int of_pci_parse_bus_range(struct device_node *node, struct resource *res) } EXPORT_SYMBOL_GPL(of_pci_parse_bus_range); +static atomic_t of_domain_nr = ATOMIC_INIT(-1); + +/* + * Get the maximum value for a domain number from the device tree + */ +static int of_get_max_pci_domain_nr(void) +{ + struct alias_prop *app; + int max_domain = -1; + + mutex_lock(&of_mutex); + list_for_each_entry(app, &aliases_lookup, link) { + if (strncmp(app->stem, "pci-domain", 10) != 0) + continue; + + max_domain = max(max_domain, app->id); + } + mutex_unlock(&of_mutex); + + return max_domain; +} + +/** + * This function will try to obtain the host bridge domain number by + * using of_alias_get_id() call with "pci-domain" as a stem. If that + * fails, a local allocator will be used. The local allocator can + * be requested to return a new domain_nr if the information is missing + * from the device tree. + * + * @node: device tree node with the domain information + * @allocate_if_missing: if DT lacks information about the domain nr, + * allocate a new number. + * + * Returns the associated domain number from DT, or a new domain number + * if DT information is missing and @allocate_if_missing is true. If + * @allocate_if_missing is false then the last allocated domain number + * will be returned. + */ +int of_pci_get_domain_nr(struct device_node *node, bool allocate_if_missing) +{ + int domain; + + domain = atomic_read(&of_domain_nr); + if (domain == -1) { + /* first run, get max defined domain nr in device tree */ + domain = of_get_max_pci_domain_nr(); + /* then set the start value for allocator to be max + 1 */ + atomic_set(&of_domain_nr, domain + 1); + } + domain = of_alias_get_id(node, "pci-domain"); + if (domain == -ENODEV) { + domain = atomic_read(&of_domain_nr); + if (allocate_if_missing) + atomic_inc(&of_domain_nr); + } + + return domain; +} +EXPORT_SYMBOL_GPL(of_pci_get_domain_nr); + #ifdef CONFIG_PCI_MSI static LIST_HEAD(of_pci_msi_chip_list); diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index dde3a4a..3a3824c 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -15,6 +15,7 @@ struct device_node *of_pci_find_child_device(struct device_node *parent, int of_pci_get_devfn(struct device_node *np); int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); +int of_pci_get_domain_nr(struct device_node *node, bool allocate_if_missing); #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { @@ -43,6 +44,12 @@ of_pci_parse_bus_range(struct device_node *node, struct resource *res) { return -EINVAL; } + +static inline int +of_pci_get_domain_nr(struct device_node *node, bool allocate_if_missing) +{ + return -1; +} #endif #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI)