From: arnd@arndb•de (Arnd Bergmann)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v7 2/6] pci: OF: Fix the conversion of IO ranges into IO resources.
Date: Fri, 14 Mar 2014 19:46:23 +0100 [thread overview]
Message-ID: <201403141946.23921.arnd@arndb.de> (raw)
In-Reply-To: <20140314171921.GY6457@e106497-lin.cambridge.arm.com>
On Friday 14 March 2014, Liviu Dudau wrote:
> You are right, that was lazy of me. What about this version?
Yes, that seems better. Thanks for fixing it up.
But back to the more important question that I realized we have
not resolved yet:
You now have two completely independent allocation functions for
logical I/O space numbers, and they will return different numbers
for any nontrivial scenario.
> +int of_pci_range_to_resource(struct of_pci_range *range,
> + struct device_node *np, struct resource *res)
> +{
> + res->flags = range->flags;
> + res->parent = res->child = res->sibling = NULL;
> + res->name = np->full_name;
> +
> + if (res->flags & IORESOURCE_IO) {
> + unsigned long port = -1;
> + int err = pci_register_io_range(range->cpu_addr, range->size);
> + if (err)
> + goto invalid_range;
> + port = pci_address_to_pio(range->cpu_addr);
> + if (port == (unsigned long)-1) {
> + err = -EINVAL;
> + goto invalid_range;
> + }
> + res->start = port;
> + } else {
This one concatenates the I/O spaces and assumes that each space starts
at bus address zero, and takes little precaution to avoid filling up IO_SPACE_LIMIT
if the sizes are too big.
>+unsigned long pci_ioremap_io(const struct resource *res, phys_addr_t phys_addr)
>+{
>+ unsigned long start, len, virt_start;
>+ int err;
>+
>+ if (res->end > IO_SPACE_LIMIT)
>+ return -EINVAL;
>+
>+ /*
>+ * try finding free space for the whole size first,
>+ * fall back to 64K if not available
>+ */
>+ len = resource_size(res);
>+ start = bitmap_find_next_zero_area(pci_iospace, IO_SPACE_PAGES,
>+ res->start / PAGE_SIZE, len / PAGE_SIZE, 0);
>+ if (start == IO_SPACE_PAGES && len > SZ_64K) {
>+ len = SZ_64K;
>+ start = 0;
>+ start = bitmap_find_next_zero_area(pci_iospace, IO_SPACE_PAGES,
>+ start, len / PAGE_SIZE, 0);
>+ }
>+
>+ /* no 64K area found */
>+ if (start == IO_SPACE_PAGES)
>+ return -ENOMEM;
>+
>+ /* ioremap physical aperture to virtual aperture */
>+ virt_start = start * PAGE_SIZE + (unsigned long)PCI_IOBASE;
>+ err = ioremap_page_range(virt_start, virt_start + len,
>+ phys_addr, __pgprot(PROT_DEVICE_nGnRE));
>+ if (err)
>+ return err;
>+
>+ bitmap_set(pci_iospace, start, len / PAGE_SIZE);
>+
>+ /* return io_offset */
>+ return start * PAGE_SIZE - res->start;
>+}
While this one will try to fall back to smaller sizes, and will honor nonzero
bus addresses.
I think we shouldn't even try to do the same thing twice, but instead just
use a single allocator. I'd prefer the one I came up with, but I realize
that I am biased here ;-)
Arnd
next prev parent reply other threads:[~2014-03-14 18:46 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
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 [this message]
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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