From: thierry.reding@gmail•com (Thierry Reding)
To: linux-arm-kernel@lists•infradead.org
Subject: [RFC PATCH 04/11] PCI: tegra: limit to MMU build only
Date: Tue, 22 Nov 2016 12:26:19 +0100 [thread overview]
Message-ID: <20161122112619.GA22862@ulmo.ba.sec> (raw)
In-Reply-To: <28079479.jInxCWkYlm@wuerfel>
On Tue, Nov 22, 2016 at 10:54:01AM +0100, Arnd Bergmann wrote:
> On Tuesday, November 22, 2016 9:40:39 AM CET Vladimir Murzin wrote:
> > On 22/11/16 09:31, Arnd Bergmann wrote:
> > > On Tuesday, November 22, 2016 9:26:01 AM CET Vladimir Murzin wrote:
> > >> This driver uses functionality which available for MMU build only,
> > >> thus add dependency on MMU.
> > >>
> > >> Cc: Thierry Reding <thierry.reding@gmail•com>
> > >> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm•com>
> > >>
> > >
> > > Can you be more specific about what requires the MMU here?
> > >
> > > Is it the I/O space remapping or something else?
> >
> > Yes it comes from I/O space remapping.
> >
> > The fill error log:
> >
> > CC drivers/pci/host/pci-tegra.o
> > In file included from ./arch/arm/include/asm/page.h:22:0,
> > from ./arch/arm/include/asm/thread_info.h:17,
> > from ./include/linux/thread_info.h:58,
> > from ./include/asm-generic/current.h:4,
> > from ./arch/arm/include/generated/asm/current.h:1,
> > from ./include/linux/mutex.h:13,
> > from ./include/linux/notifier.h:13,
> > from ./include/linux/clk.h:17,
> > from drivers/pci/host/pci-tegra.c:29:
> > drivers/pci/host/pci-tegra.c: In function 'tegra_pcie_bus_alloc':
> > drivers/pci/host/pci-tegra.c:388:27: error: 'L_PTE_PRESENT' undeclared (first use in this function)
> > pgprot_t prot = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
>
>
> That is not the I/O space, that is the config space.
>
> Not sure what a better alternative would be, but the manual selection
> of page flags makes the driver non-portable and dependent on architecture
> specifics that it really shouldn't have to worry about.
>
> In common PCI code, we use pgprot_device(PAGE_KERNEL)) at some point,
> and that sounds like the right thing to do, but ARM doesn't provide
> an override for it and the fallback is pgprot_noncached(), which is
> probably wrong here.
Actually I think pgprot_noncached() is correct. Very early on we used to
map this using ioremap() and I remember that working. I also just tested
the pci-tegra driver with pgprot_device(PAGE_KERNEL) instead of the ARM-
specific flags and it seems to work well.
Thierry
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next prev parent reply other threads:[~2016-11-22 11:26 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-22 9:25 [RFC PATCH 00/11] Allow NOMMU for MULTIPLATFORM Vladimir Murzin
2016-11-22 9:25 ` [RFC PATCH 01/11] ARM: NOMMU: define stubs for fixup Vladimir Murzin
2016-11-22 9:48 ` Russell King - ARM Linux
2016-11-22 9:54 ` Vladimir Murzin
2016-11-22 9:25 ` [RFC PATCH 02/11] ARM: ep93xx: select ARM_PATCH_PHYS_VIRT for MMU builds only Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 03/11] ARM: omap: do not select HIGHMEM explicitly Vladimir Murzin
2016-11-22 9:51 ` Russell King - ARM Linux
2016-11-23 15:49 ` Tony Lindgren
2016-11-23 16:08 ` Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 04/11] PCI: tegra: limit to MMU build only Vladimir Murzin
2016-11-22 9:31 ` Arnd Bergmann
2016-11-22 9:40 ` Vladimir Murzin
2016-11-22 9:54 ` Arnd Bergmann
2016-11-22 9:58 ` Vladimir Murzin
2016-11-22 11:26 ` Thierry Reding [this message]
2016-11-25 10:49 ` Vladimir Murzin
2016-11-22 16:15 ` Stephen Warren
2016-11-22 21:16 ` Arnd Bergmann
2016-11-22 22:27 ` Stephen Warren
2016-11-22 22:52 ` Arnd Bergmann
2016-11-22 9:26 ` [RFC PATCH 05/11] ARM: move arm_heavy_mb to MMU/noMMU neutral place Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 06/11] ARM: tlbflush: drop dependency on CONFIG_SMP Vladimir Murzin
2016-11-22 10:03 ` Russell King - ARM Linux
2016-11-22 13:36 ` Vladimir Murzin
2016-11-24 17:41 ` Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 07/11] ARM: sleep: allow it to be build for R-class Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 08/11] ARM: NOMMU: define debug_ll_io_ini Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 09/11] ARM: NOMMU: define SECTION_xxx macros Vladimir Murzin
2016-11-22 10:07 ` Russell King - ARM Linux
2016-11-22 11:50 ` Vladimir Murzin
2016-11-22 11:54 ` Russell King - ARM Linux
2016-11-22 17:03 ` Vladimir Murzin
2016-11-24 17:38 ` Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 10/11] ARM: NOMMU: define __arm_ioremap_exec and pci_ioremap functions Vladimir Murzin
2016-11-22 9:26 ` [RFC PATCH 11/11] ARM: Allow ARCH_MULTIPLATFORM to be selected for NOMMU Vladimir Murzin
2016-11-22 10:17 ` Arnd Bergmann
2016-11-22 16:57 ` Vladimir Murzin
2016-11-23 15:48 ` Afzal Mohammed
2016-11-23 16:07 ` Vladimir Murzin
2016-11-24 17:28 ` Afzal Mohammed
2016-11-24 17:33 ` Vladimir Murzin
2016-11-24 18:09 ` Afzal Mohammed
2016-11-23 19:16 ` Russell King - ARM Linux
2016-11-24 17:25 ` Afzal Mohammed
2016-11-24 17:35 ` Russell King - ARM Linux
2016-11-24 18:07 ` Afzal Mohammed
2016-11-24 18:45 ` Russell King - ARM Linux
2016-11-25 11:20 ` Vladimir Murzin
2016-11-23 15:55 ` Tony Lindgren
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