From: bhelgaas@google•com (Bjorn Helgaas)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v7 1/6] pci: Introduce pci_register_io_range() helper function.
Date: Fri, 4 Apr 2014 18:19:53 -0600 [thread overview]
Message-ID: <20140405001953.GE15806@google.com> (raw)
In-Reply-To: <1394811272-1547-2-git-send-email-Liviu.Dudau@arm.com>
On Fri, Mar 14, 2014 at 03:34:27PM +0000, Liviu Dudau wrote:
> Some architectures do not share x86 simple view of the PCI I/O space
> and instead use a range of addresses that map to bus addresses. For
> some architectures these ranges will be expressed by OF bindings
> in a device tree file.
It's true that the current Linux "x86 view of PCI I/O space" is pretty
simple and limited. But I don't think that's a fundamental x86 limitation
(other than the fact that the actual INB/OUTB/etc. CPU instructions
themselves are limited to a single 64K I/O port space).
Host bridges on x86 could have MMIO apertures that turn CPU memory accesses
into PCI port accesses. We could implement any number of I/O port spaces
this way, by making the kernel inb()/outb()/etc. interfaces smart enough to
use the memory-mapped space instead of (or in addition to) the
INB/OUTB/etc. instructions.
ia64 does this (see arch/ia64/include/asm/io.h for a little description)
and I think maybe one or two other arches have something similar.
> Introduce a pci_register_io_range() helper function that can be used
> by the architecture code 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.
I don't quite see how you intend to use this, because this series doesn't
include any non-stub implementation of pci_register_io_range().
Is this anything like the ia64 strategy I mentioned above? If so, it would
be really nice to unify some of this stuff.
> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm•com>
> Acked-by: Grant Likely <grant.likely@linaro•org>
> Tested-by: Tanmay Inamdar <tinamdar@apm•com>
> ---
> drivers/of/address.c | 9 +++++++++
> include/linux/of_address.h | 1 +
> 2 files changed, 10 insertions(+)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 1a54f1f..be958ed 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -619,6 +619,15 @@ const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
> }
> EXPORT_SYMBOL(of_get_address);
>
> +int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
> +{
> +#ifndef PCI_IOBASE
> + return -EINVAL;
> +#else
> + return 0;
> +#endif
> +}
> +
> unsigned long __weak pci_address_to_pio(phys_addr_t address)
> {
> if (address > IO_SPACE_LIMIT)
> diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> index 5f6ed6b..40c418d 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -56,6 +56,7 @@ 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 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
> --
> 1.9.0
>
next prev parent reply other threads:[~2014-04-05 0:19 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-14 15:34 [PATCH v7 0/6] Support for creating generic host_bridge from device tree Liviu Dudau
2014-03-14 15:34 ` [PATCH v7 1/6] pci: Introduce pci_register_io_range() helper function Liviu Dudau
2014-04-05 0:19 ` Bjorn Helgaas [this message]
2014-04-06 9:49 ` Benjamin Herrenschmidt
2014-04-07 8:35 ` Liviu Dudau
2014-04-07 9:13 ` Benjamin Herrenschmidt
2014-04-07 11:16 ` Arnd Bergmann
2014-04-07 8:31 ` Liviu Dudau
2014-04-07 11:36 ` Arnd Bergmann
2014-04-07 13:42 ` Liviu Dudau
2014-04-07 17:58 ` Bjorn Helgaas
2014-04-08 9:50 ` Liviu Dudau
2014-04-08 10:22 ` Arnd Bergmann
2014-04-08 16:54 ` Bjorn Helgaas
2014-06-26 8:59 ` Catalin Marinas
2014-06-26 9:30 ` Liviu Dudau
2014-06-26 14:11 ` Catalin Marinas
2014-06-26 14:14 ` Will Deacon
2014-06-27 0:44 ` Rob Herring
2014-06-27 11:03 ` Arnd Bergmann
2014-06-27 12:49 ` Will Deacon
2014-06-27 13:16 ` Arnd Bergmann
2014-06-27 13:38 ` Catalin Marinas
2014-06-27 16:15 ` Rob Herring
2014-06-30 10:17 ` Will Deacon
2014-06-27 14:14 ` Catalin Marinas
2014-06-27 14:55 ` Bjorn Helgaas
2014-06-27 15:18 ` Liviu Dudau
2014-04-07 23:21 ` Bjorn Helgaas
2014-04-08 7:12 ` Arnd Bergmann
2014-04-08 9:49 ` Liviu Dudau
2014-04-08 10:11 ` Arnd Bergmann
2014-04-08 16:48 ` Bjorn Helgaas
2014-03-14 15:34 ` [PATCH v7 2/6] pci: OF: Fix the conversion of IO ranges into IO resources Liviu Dudau
2014-03-14 17:05 ` Arnd Bergmann
2014-03-14 17:19 ` Liviu Dudau
2014-03-14 18:46 ` Arnd Bergmann
2014-03-14 19:00 ` Liviu Dudau
2014-03-14 19:16 ` Arnd Bergmann
2014-03-17 13:41 ` Liviu Dudau
2014-03-14 15:34 ` [PATCH v7 3/6] pci: Create pci_host_bridge before its associated bus in pci_create_root_bus Liviu Dudau
2014-03-14 15:34 ` [PATCH v7 4/6] pci: Introduce a domain number for pci_host_bridge Liviu Dudau
2014-04-05 0:00 ` Bjorn Helgaas
2014-04-07 8:46 ` Liviu Dudau
2014-04-07 9:14 ` Benjamin Herrenschmidt
2014-04-07 10:07 ` Liviu Dudau
2014-04-07 22:44 ` Bjorn Helgaas
2014-04-08 10:20 ` Liviu Dudau
2014-04-08 16:28 ` Bjorn Helgaas
2014-04-09 12:07 ` Liviu Dudau
2014-04-09 14:02 ` Bjorn Helgaas
2014-04-09 14:08 ` Arnd Bergmann
2014-04-09 23:49 ` Benjamin Herrenschmidt
2014-04-10 1:27 ` Liviu Dudau
2014-04-10 3:48 ` Bjorn Helgaas
2014-04-10 8:00 ` Arnd Bergmann
2014-04-10 13:50 ` Bjorn Helgaas
2014-04-10 14:07 ` Arnd Bergmann
2014-04-10 14:53 ` Liviu Dudau
2014-04-10 20:46 ` Arnd Bergmann
2014-04-11 5:01 ` Benjamin Herrenschmidt
2014-04-11 8:36 ` Arnd Bergmann
2014-04-11 9:16 ` Benjamin Herrenschmidt
2014-04-11 9:22 ` Liviu Dudau
2014-04-11 13:51 ` Arnd Bergmann
2014-07-01 16:37 ` Liviu Dudau
2014-07-04 14:57 ` Liviu Dudau
2014-07-08 1:11 ` Bjorn Helgaas
2014-07-08 10:21 ` Liviu Dudau
2014-03-14 15:34 ` [PATCH v7 5/6] pci: Export find_pci_host_bridge() function Liviu Dudau
2014-04-04 23:39 ` Bjorn Helgaas
2014-04-07 14:20 ` Liviu Dudau
2014-04-07 14:38 ` One Thousand Gnomes
2014-03-14 15:34 ` [PATCH v7 6/6] pci: Add support for creating a generic host_bridge from device tree Liviu Dudau
2014-04-08 12:57 ` Hanjun Guo
2014-04-08 13:09 ` Liviu Dudau
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