| Message ID | 1407860725-25202-4-git-send-email-Liviu.Dudau@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Aug 12, 2014 at 05:25:16PM +0100, Liviu Dudau wrote: > Some architectures do not have a simple view of the PCI I/O space > and instead use a range of CPU addresses that map to bus addresses. > For some architectures these ranges will be expressed by OF bindings > in a device tree file. > > This patch introduces a pci_register_io_range() helper function with > a generic implementation that can be used by such architectures to > keep track of the I/O ranges described by the PCI bindings. If the > PCI_IOBASE macro is not defined that signals lack of support for PCI > and we return an error. > > In order to retrieve the CPU address associated with an I/O port, a > new helper function pci_pio_to_address() is introduced. This will > search in the list of ranges registered with pci_register_io_range() > and return the CPU address that corresponds to the given port. > > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > --- > drivers/of/address.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/of_address.h | 2 + > 2 files changed, 97 insertions(+) Actually, I think we moved too much code into drivers/of/. Is there anything OF specific about this code to live here (apart from OF_BAD_ADDR)? I think driver/pci/ more appropriate? Otherwise it looks fine to me.
On Mon, Aug 18, 2014 at 03:26:04PM +0100, Catalin Marinas wrote: > On Tue, Aug 12, 2014 at 05:25:16PM +0100, Liviu Dudau wrote: > > Some architectures do not have a simple view of the PCI I/O space > > and instead use a range of CPU addresses that map to bus addresses. > > For some architectures these ranges will be expressed by OF bindings > > in a device tree file. > > > > This patch introduces a pci_register_io_range() helper function with > > a generic implementation that can be used by such architectures to > > keep track of the I/O ranges described by the PCI bindings. If the > > PCI_IOBASE macro is not defined that signals lack of support for PCI > > and we return an error. > > > > In order to retrieve the CPU address associated with an I/O port, a > > new helper function pci_pio_to_address() is introduced. This will > > search in the list of ranges registered with pci_register_io_range() > > and return the CPU address that corresponds to the given port. > > > > Cc: Grant Likely <grant.likely@linaro.org> > > Cc: Rob Herring <robh+dt@kernel.org> > > Cc: Arnd Bergmann <arnd@arndb.de> > > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > > --- > > drivers/of/address.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++ > > include/linux/of_address.h | 2 + > > 2 files changed, 97 insertions(+) > > Actually, I think we moved too much code into drivers/of/. Is there > anything OF specific about this code to live here (apart from > OF_BAD_ADDR)? I think driver/pci/ more appropriate? I have no strong preference for one place vs the other. While this does not use any OF specific code, it should be called only from OF enabled code. So the relationship is not one of depending on of_* but on being dependent on. > > Otherwise it looks fine to me. Thanks! Would be nice if you can prod at the kernel summit other maintainers for ACKs. Best regards, Liviu > > -- > Catalin > -- > 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, Aug 18, 2014 at 10:34:46PM +0100, Liviu Dudau wrote: > On Mon, Aug 18, 2014 at 03:26:04PM +0100, Catalin Marinas wrote: > > On Tue, Aug 12, 2014 at 05:25:16PM +0100, Liviu Dudau wrote: > > > Some architectures do not have a simple view of the PCI I/O space > > > and instead use a range of CPU addresses that map to bus addresses. > > > For some architectures these ranges will be expressed by OF bindings > > > in a device tree file. > > > > > > This patch introduces a pci_register_io_range() helper function with > > > a generic implementation that can be used by such architectures to > > > keep track of the I/O ranges described by the PCI bindings. If the > > > PCI_IOBASE macro is not defined that signals lack of support for PCI > > > and we return an error. > > > > > > In order to retrieve the CPU address associated with an I/O port, a > > > new helper function pci_pio_to_address() is introduced. This will > > > search in the list of ranges registered with pci_register_io_range() > > > and return the CPU address that corresponds to the given port. > > > > > > Cc: Grant Likely <grant.likely@linaro.org> > > > Cc: Rob Herring <robh+dt@kernel.org> > > > Cc: Arnd Bergmann <arnd@arndb.de> > > > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > > > --- > > > drivers/of/address.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++ > > > include/linux/of_address.h | 2 + > > > 2 files changed, 97 insertions(+) > > > > Actually, I think we moved too much code into drivers/of/. Is there > > anything OF specific about this code to live here (apart from > > OF_BAD_ADDR)? I think driver/pci/ more appropriate? > > I have no strong preference for one place vs the other. While this does > not use any OF specific code, it should be called only from OF enabled > code. So the relationship is not one of depending on of_* but on being > dependent on. In this case it's probably ok to keep them here for the time being. I wonder whether it would also be useful for ACPI. But I have no idea how ACPI would fit with the ACPI patches.
On Tue, Aug 12, 2014 at 11:25 AM, Liviu Dudau <Liviu.Dudau@arm.com> wrote: > Some architectures do not have a simple view of the PCI I/O space > and instead use a range of CPU addresses that map to bus addresses. > For some architectures these ranges will be expressed by OF bindings > in a device tree file. > > This patch introduces a pci_register_io_range() helper function with > a generic implementation that can be used by such architectures to > keep track of the I/O ranges described by the PCI bindings. If the > PCI_IOBASE macro is not defined that signals lack of support for PCI > and we return an error. > > In order to retrieve the CPU address associated with an I/O port, a > new helper function pci_pio_to_address() is introduced. This will > search in the list of ranges registered with pci_register_io_range() > and return the CPU address that corresponds to the given port. > > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> Acked-by: Rob Herring <robh@kernel.org> > --- > drivers/of/address.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/of_address.h | 2 + > 2 files changed, 97 insertions(+) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 5edfcb0..4dab700 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -5,6 +5,7 @@ > #include <linux/module.h> > #include <linux/of_address.h> > #include <linux/pci_regs.h> > +#include <linux/slab.h> > #include <linux/string.h> > > /* Max address size we deal with */ > @@ -601,12 +602,106 @@ const __be32 *of_get_address(struct device_node *dev, int index, u64 *size, > } > EXPORT_SYMBOL(of_get_address); > > +#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) > +{ > +#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) > + return 0; > + allocated_size += range->size; > + } > + spin_unlock(&io_range_lock); > + > + /* 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) > + return -E2BIG; > + > + size = SZ_64K; > + pr_warn("Requested IO range too big, new size set to 64K\n"); > + } > + > + /* add the range to the list */ > + range = kzalloc(sizeof(*range), GFP_KERNEL); > + if (!range) > + return -ENOMEM; > + > + range->start = addr; > + range->size = size; > + > + list_add_tail(&range->list, &io_range_list); > +#endif > + > + return 0; > +} > + > +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); > +#endif > + > + return address; > +} > + > unsigned long __weak pci_address_to_pio(phys_addr_t address) > { > +#ifdef PCI_IOBASE > + struct io_range *res; > + resource_size_t offset = 0; > + > + list_for_each_entry(res, &io_range_list, list) { > + if (address >= res->start && > + address < res->start + res->size) { > + return res->start - address + offset; > + } > + offset += res->size; > + } > + > + return (unsigned long)-1; > +#else > if (address > IO_SPACE_LIMIT) > return (unsigned long)-1; > > return (unsigned long) address; > +#endif > } > > static int __of_address_to_resource(struct device_node *dev, > diff --git a/include/linux/of_address.h b/include/linux/of_address.h > index c13b878..28e6836 100644 > --- a/include/linux/of_address.h > +++ b/include/linux/of_address.h > @@ -55,7 +55,9 @@ extern void __iomem *of_iomap(struct device_node *device, int index); > extern const __be32 *of_get_address(struct device_node *dev, int index, > u64 *size, unsigned int *flags); > > +extern int pci_register_io_range(phys_addr_t addr, resource_size_t size); > extern unsigned long pci_address_to_pio(phys_addr_t addr); > +extern phys_addr_t pci_pio_to_address(unsigned long pio); > > extern int of_pci_range_parser_init(struct of_pci_range_parser *parser, > struct device_node *node); > -- > 2.0.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On 2014/8/13 0:25, Liviu Dudau wrote: > Some architectures do not have a simple view of the PCI I/O space > and instead use a range of CPU addresses that map to bus addresses. > For some architectures these ranges will be expressed by OF bindings > in a device tree file. > > This patch introduces a pci_register_io_range() helper function with > a generic implementation that can be used by such architectures to > keep track of the I/O ranges described by the PCI bindings. If the > PCI_IOBASE macro is not defined that signals lack of support for PCI > and we return an error. > > In order to retrieve the CPU address associated with an I/O port, a > new helper function pci_pio_to_address() is introduced. This will > search in the list of ranges registered with pci_register_io_range() > and return the CPU address that corresponds to the given port. > > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > --- > drivers/of/address.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/of_address.h | 2 + > 2 files changed, 97 insertions(+) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 5edfcb0..4dab700 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -5,6 +5,7 @@ > #include <linux/module.h> > #include <linux/of_address.h> > #include <linux/pci_regs.h> > +#include <linux/slab.h> > #include <linux/string.h> > > /* Max address size we deal with */ > @@ -601,12 +602,106 @@ const __be32 *of_get_address(struct device_node *dev, int index, u64 *size, > } > EXPORT_SYMBOL(of_get_address); > > +#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) > +{ > +#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) > + return 0; > + allocated_size += range->size; > + } > + spin_unlock(&io_range_lock); > + > + /* 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) > + return -E2BIG; > + > + size = SZ_64K; > + pr_warn("Requested IO range too big, new size set to 64K\n"); > + } > + > + /* add the range to the list */ > + range = kzalloc(sizeof(*range), GFP_KERNEL); > + if (!range) > + return -ENOMEM; > + > + range->start = addr; > + range->size = size; > + > + list_add_tail(&range->list, &io_range_list); Need spin_lock() here ? > +#endif > + > + return 0; > +} > + > +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); > +#endif > + > + return address; > +} > + > unsigned long __weak pci_address_to_pio(phys_addr_t address) > { > +#ifdef PCI_IOBASE > + struct io_range *res; > + resource_size_t offset = 0; > + > + list_for_each_entry(res, &io_range_list, list) { And here. > + if (address >= res->start && > + address < res->start + res->size) { > + return res->start - address + offset; > + } > + offset += res->size; > + } > + > + return (unsigned long)-1; > +#else > if (address > IO_SPACE_LIMIT) > return (unsigned long)-1; > > return (unsigned long) address; > +#endif > } > > static int __of_address_to_resource(struct device_node *dev, > diff --git a/include/linux/of_address.h b/include/linux/of_address.h > index c13b878..28e6836 100644 > --- a/include/linux/of_address.h > +++ b/include/linux/of_address.h > @@ -55,7 +55,9 @@ extern void __iomem *of_iomap(struct device_node *device, int index); > extern const __be32 *of_get_address(struct device_node *dev, int index, > u64 *size, unsigned int *flags); > > +extern int pci_register_io_range(phys_addr_t addr, resource_size_t size); > extern unsigned long pci_address_to_pio(phys_addr_t addr); > +extern phys_addr_t pci_pio_to_address(unsigned long pio); > > extern int of_pci_range_parser_init(struct of_pci_range_parser *parser, > struct device_node *node); >
diff --git a/drivers/of/address.c b/drivers/of/address.c index 5edfcb0..4dab700 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -5,6 +5,7 @@ #include <linux/module.h> #include <linux/of_address.h> #include <linux/pci_regs.h> +#include <linux/slab.h> #include <linux/string.h> /* Max address size we deal with */ @@ -601,12 +602,106 @@ const __be32 *of_get_address(struct device_node *dev, int index, u64 *size, } EXPORT_SYMBOL(of_get_address); +#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) +{ +#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) + return 0; + allocated_size += range->size; + } + spin_unlock(&io_range_lock); + + /* 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) + return -E2BIG; + + size = SZ_64K; + pr_warn("Requested IO range too big, new size set to 64K\n"); + } + + /* add the range to the list */ + range = kzalloc(sizeof(*range), GFP_KERNEL); + if (!range) + return -ENOMEM; + + range->start = addr; + range->size = size; + + list_add_tail(&range->list, &io_range_list); +#endif + + return 0; +} + +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); +#endif + + return address; +} + unsigned long __weak pci_address_to_pio(phys_addr_t address) { +#ifdef PCI_IOBASE + struct io_range *res; + resource_size_t offset = 0; + + list_for_each_entry(res, &io_range_list, list) { + if (address >= res->start && + address < res->start + res->size) { + return res->start - address + offset; + } + offset += res->size; + } + + return (unsigned long)-1; +#else if (address > IO_SPACE_LIMIT) return (unsigned long)-1; return (unsigned long) address; +#endif } static int __of_address_to_resource(struct device_node *dev, diff --git a/include/linux/of_address.h b/include/linux/of_address.h index c13b878..28e6836 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -55,7 +55,9 @@ extern void __iomem *of_iomap(struct device_node *device, int index); extern const __be32 *of_get_address(struct device_node *dev, int index, u64 *size, unsigned int *flags); +extern int pci_register_io_range(phys_addr_t addr, resource_size_t size); extern unsigned long pci_address_to_pio(phys_addr_t addr); +extern phys_addr_t pci_pio_to_address(unsigned long pio); extern int of_pci_range_parser_init(struct of_pci_range_parser *parser, struct device_node *node);
Some architectures do not have a simple view of the PCI I/O space and instead use a range of CPU addresses that map to bus addresses. For some architectures these ranges will be expressed by OF bindings in a device tree file. This patch introduces a pci_register_io_range() helper function with a generic implementation that can be used by such architectures to keep track of the I/O ranges described by the PCI bindings. If the PCI_IOBASE macro is not defined that signals lack of support for PCI and we return an error. In order to retrieve the CPU address associated with an I/O port, a new helper function pci_pio_to_address() is introduced. This will search in the list of ranges registered with pci_register_io_range() and return the CPU address that corresponds to the given port. Cc: Grant Likely <grant.likely@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> --- drivers/of/address.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_address.h | 2 + 2 files changed, 97 insertions(+)