2015-04-03 19:32:41

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

On Tue, Mar 31, 2015 at 07:57:47PM -0700, Yinghai Lu wrote:
> David Ahern found commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows
> to fit in upstream windows") broke booting on sparc/T5-8.
>
> In the boot log, there is
> pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address
> 0x110204000)
> but that only could happen when dma_addr_t is 32-bit.
>
> According to David Miller, all DMA occurs behind an IOMMU and these
> IOMMUs only support 32-bit addressing, therefore dma_addr_t is
> 32-bit on sparc64.
>
> Let's introduce pci_bus_addr_t instead of using dma_addr_t,
> and pci_bus_addr_t will be 64-bit on 64-bit platform or X86_PAE.
>
> Fixes: commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows")
> Fixes: commit 23b13bc76f35 ("PCI: Fail safely if we can't handle BARs larger than 4GB")
> Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
> Reported-by: David Ahern <[email protected]>
> Tested-by: David Ahern <[email protected]>
> Signed-off-by: Yinghai Lu <[email protected]>
> Cc: <[email protected]> #3.19
> ---
> drivers/pci/Kconfig | 4 ++++
> drivers/pci/bus.c | 10 +++++-----
> drivers/pci/probe.c | 12 ++++++------
> include/linux/pci.h | 12 +++++++++---
> 4 files changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> index 7a8f1c5..6a5a269 100644
> --- a/drivers/pci/Kconfig
> +++ b/drivers/pci/Kconfig
> @@ -1,6 +1,10 @@
> #
> # PCI configuration
> #
> +config PCI_BUS_ADDR_T_64BIT
> + def_bool y if (64BIT || X86_PAE)
> + depends on PCI

We're going to use pci_bus_addr_t in some places where we previously used
dma_addr_t, which means pci_bus_addr_t should be at least as large as
dma_addr_t. Can you enforce that directly, e.g., with something like this?

def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT || X86_PAE)

Unless we do something like that, I think this may break these arches by
changing the addresses in struct pci_bus_region from 64 bits to 32:

arch/arm/Kconfig:
XEN selects ARCH_DMA_ADDR_T_64BIT but not 64BIT, so it would not
set PCI_BUS_ADDR_T_64BIT

arch/arm/mach-axxia/Kconfig:
ARCH_AXXIA selects ARCH_DMA_ADDR_T_64BIT but not 64BIT, so it
would not set PCI_BUS_ADDR_T_64BIT

arch/arm/mach-exynos/Kconfig:
SOC_EXYNOS5440 selects ARCH_DMA_ADDR_T_64BIT if ARM_LPAE, but not
64BIT, so it would not set PCI_BUS_ADDR_T_64BIT

arch/arm/mach-highbank/Kconfig:
ARCH_HIGHBANK selects ARCH_DMA_ADDR_T_64BIT if ARM_LPAE, but not
64BIT, so it would not set PCI_BUS_ADDR_T_64BIT

arch/arm/mach-shmobile/Kconfig:
ARCH_SHMOBILE_MULTI selects ARCH_DMA_ADDR_T_64BIT if ARM_LPAE, but
not 64BIT, so it would not set PCI_BUS_ADDR_T_64BIT

arch/mips/Kconfig:
sets ARCH_DMA_ADDR_T_64BIT if (HIGHMEM && ARCH_PHYS_ADDR_T_64BIT)
|| 64BIT, so if we have (HIGHMEM && ARCH_PHYS_ADDR_T_64BIT) but not
64BIT, it would not set PCI_BUS_ADDR_T_64BIT

arch/powerpc/Kconfig:
sets ARCH_DMA_ADDR_T_64BIT if ARCH_PHYS_ADDR_T_64BIT, which isn't
trivially identical to (64BIT || X86_PAE), so we may not set
PCI_BUS_ADDR_T_64BIT in all cases where we set
ARCH_DMA_ADDR_T_64BIT

arch/x86/Kconfig:
sets ARCH_DMA_ADDR_T_64BIT if X86_64 || HIGHMEM64G, which isn't
trivially identical to (64BIT || X86_PAE), so we may not set
PCI_BUS_ADDR_T_64BIT in all cases where we set
ARCH_DMA_ADDR_T_64BIT

> config PCI_MSI
> bool "Message Signaled Interrupts (MSI and MSI-X)"
> depends on PCI
> diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
> index 90fa3a7..6fbd3f2 100644
> --- a/drivers/pci/bus.c
> +++ b/drivers/pci/bus.c
> @@ -92,11 +92,11 @@ void pci_bus_remove_resources(struct pci_bus *bus)
> }
>
> static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
> -#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
> +#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
> static struct pci_bus_region pci_64_bit = {0,
> - (dma_addr_t) 0xffffffffffffffffULL};
> -static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,
> - (dma_addr_t) 0xffffffffffffffffULL};
> + (pci_bus_addr_t) 0xffffffffffffffffULL};
> +static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
> + (pci_bus_addr_t) 0xffffffffffffffffULL};
> #endif
>
> /*
> @@ -200,7 +200,7 @@ int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
> resource_size_t),
> void *alignf_data)
> {
> -#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
> +#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
> int rc;
>
> if (res->flags & IORESOURCE_MEM_64) {
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 8d2f400..f71cb7c 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -253,8 +253,8 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
> }
>
> if (res->flags & IORESOURCE_MEM_64) {
> - if ((sizeof(dma_addr_t) < 8 || sizeof(resource_size_t) < 8) &&
> - sz64 > 0x100000000ULL) {
> + if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
> + && sz64 > 0x100000000ULL) {
> res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
> res->start = 0;
> res->end = 0;
> @@ -263,7 +263,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
> goto out;
> }
>
> - if ((sizeof(dma_addr_t) < 8) && l) {
> + if ((sizeof(pci_bus_addr_t) < 8) && l) {
> /* Above 32-bit boundary; try to reallocate */
> res->flags |= IORESOURCE_UNSET;
> res->start = 0;
> @@ -398,7 +398,7 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
> struct pci_dev *dev = child->self;
> u16 mem_base_lo, mem_limit_lo;
> u64 base64, limit64;
> - dma_addr_t base, limit;
> + pci_bus_addr_t base, limit;
> struct pci_bus_region region;
> struct resource *res;
>
> @@ -425,8 +425,8 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
> }
> }
>
> - base = (dma_addr_t) base64;
> - limit = (dma_addr_t) limit64;
> + base = (pci_bus_addr_t) base64;
> + limit = (pci_bus_addr_t) limit64;
>
> if (base != base64) {
> dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 211e9da..6021bbe 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -573,9 +573,15 @@ int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
> int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
> int reg, int len, u32 val);
>
> +#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
> +typedef u64 pci_bus_addr_t;
> +#else
> +typedef u32 pci_bus_addr_t;
> +#endif
> +
> struct pci_bus_region {
> - dma_addr_t start;
> - dma_addr_t end;
> + pci_bus_addr_t start;
> + pci_bus_addr_t end;
> };
>
> struct pci_dynids {
> @@ -1124,7 +1130,7 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
>
> int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
>
> -static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
> +static inline pci_bus_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
> {
> struct pci_bus_region region;
>
> --
> 1.8.4.5
>


2015-04-03 20:52:11

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

[+cc Sam (commented on previous versions), Russell, linux-arm-kernel, Ralf,
linux-mips, Ben, linuxppc-dev, x86]

On Fri, Apr 03, 2015 at 02:32:34PM -0500, Bjorn Helgaas wrote:
> On Tue, Mar 31, 2015 at 07:57:47PM -0700, Yinghai Lu wrote:
> > David Ahern found commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows
> > to fit in upstream windows") broke booting on sparc/T5-8.
> >
> > In the boot log, there is
> > pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address
> > 0x110204000)
> > but that only could happen when dma_addr_t is 32-bit.
> >
> > According to David Miller, all DMA occurs behind an IOMMU and these
> > IOMMUs only support 32-bit addressing, therefore dma_addr_t is
> > 32-bit on sparc64.
> >
> > Let's introduce pci_bus_addr_t instead of using dma_addr_t,
> > and pci_bus_addr_t will be 64-bit on 64-bit platform or X86_PAE.
> >
> > Fixes: commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows")
> > Fixes: commit 23b13bc76f35 ("PCI: Fail safely if we can't handle BARs larger than 4GB")
> > Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
> > Reported-by: David Ahern <[email protected]>
> > Tested-by: David Ahern <[email protected]>
> > Signed-off-by: Yinghai Lu <[email protected]>
> > Cc: <[email protected]> #3.19
> > ---
> > drivers/pci/Kconfig | 4 ++++
> > drivers/pci/bus.c | 10 +++++-----
> > drivers/pci/probe.c | 12 ++++++------
> > include/linux/pci.h | 12 +++++++++---
> > 4 files changed, 24 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> > index 7a8f1c5..6a5a269 100644
> > --- a/drivers/pci/Kconfig
> > +++ b/drivers/pci/Kconfig
> > @@ -1,6 +1,10 @@
> > #
> > # PCI configuration
> > #
> > +config PCI_BUS_ADDR_T_64BIT
> > + def_bool y if (64BIT || X86_PAE)
> > + depends on PCI
>
> We're going to use pci_bus_addr_t in some places where we previously used
> dma_addr_t, which means pci_bus_addr_t should be at least as large as
> dma_addr_t. Can you enforce that directly, e.g., with something like this?
>
> def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT || X86_PAE)
>
> Unless we do something like that, I think this may break these arches by
> changing the addresses in struct pci_bus_region from 64 bits to 32:
>
> arch/arm/Kconfig:
> XEN selects ARCH_DMA_ADDR_T_64BIT but not 64BIT, so it would not
> set PCI_BUS_ADDR_T_64BIT
>
> arch/arm/mach-axxia/Kconfig:
> ARCH_AXXIA selects ARCH_DMA_ADDR_T_64BIT but not 64BIT, so it
> would not set PCI_BUS_ADDR_T_64BIT
>
> arch/arm/mach-exynos/Kconfig:
> SOC_EXYNOS5440 selects ARCH_DMA_ADDR_T_64BIT if ARM_LPAE, but not
> 64BIT, so it would not set PCI_BUS_ADDR_T_64BIT
>
> arch/arm/mach-highbank/Kconfig:
> ARCH_HIGHBANK selects ARCH_DMA_ADDR_T_64BIT if ARM_LPAE, but not
> 64BIT, so it would not set PCI_BUS_ADDR_T_64BIT
>
> arch/arm/mach-shmobile/Kconfig:
> ARCH_SHMOBILE_MULTI selects ARCH_DMA_ADDR_T_64BIT if ARM_LPAE, but
> not 64BIT, so it would not set PCI_BUS_ADDR_T_64BIT
>
> arch/mips/Kconfig:
> sets ARCH_DMA_ADDR_T_64BIT if (HIGHMEM && ARCH_PHYS_ADDR_T_64BIT)
> || 64BIT, so if we have (HIGHMEM && ARCH_PHYS_ADDR_T_64BIT) but not
> 64BIT, it would not set PCI_BUS_ADDR_T_64BIT
>
> arch/powerpc/Kconfig:
> sets ARCH_DMA_ADDR_T_64BIT if ARCH_PHYS_ADDR_T_64BIT, which isn't
> trivially identical to (64BIT || X86_PAE), so we may not set
> PCI_BUS_ADDR_T_64BIT in all cases where we set
> ARCH_DMA_ADDR_T_64BIT
>
> arch/x86/Kconfig:
> sets ARCH_DMA_ADDR_T_64BIT if X86_64 || HIGHMEM64G, which isn't
> trivially identical to (64BIT || X86_PAE), so we may not set
> PCI_BUS_ADDR_T_64BIT in all cases where we set
> ARCH_DMA_ADDR_T_64BIT
>
> > config PCI_MSI
> > bool "Message Signaled Interrupts (MSI and MSI-X)"
> > depends on PCI
> > diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
> > index 90fa3a7..6fbd3f2 100644
> > --- a/drivers/pci/bus.c
> > +++ b/drivers/pci/bus.c
> > @@ -92,11 +92,11 @@ void pci_bus_remove_resources(struct pci_bus *bus)
> > }
> >
> > static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
> > -#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
> > +#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
> > static struct pci_bus_region pci_64_bit = {0,
> > - (dma_addr_t) 0xffffffffffffffffULL};
> > -static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,
> > - (dma_addr_t) 0xffffffffffffffffULL};
> > + (pci_bus_addr_t) 0xffffffffffffffffULL};
> > +static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
> > + (pci_bus_addr_t) 0xffffffffffffffffULL};
> > #endif
> >
> > /*
> > @@ -200,7 +200,7 @@ int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
> > resource_size_t),
> > void *alignf_data)
> > {
> > -#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
> > +#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
> > int rc;
> >
> > if (res->flags & IORESOURCE_MEM_64) {
> > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> > index 8d2f400..f71cb7c 100644
> > --- a/drivers/pci/probe.c
> > +++ b/drivers/pci/probe.c
> > @@ -253,8 +253,8 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
> > }
> >
> > if (res->flags & IORESOURCE_MEM_64) {
> > - if ((sizeof(dma_addr_t) < 8 || sizeof(resource_size_t) < 8) &&
> > - sz64 > 0x100000000ULL) {
> > + if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
> > + && sz64 > 0x100000000ULL) {
> > res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
> > res->start = 0;
> > res->end = 0;
> > @@ -263,7 +263,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
> > goto out;
> > }
> >
> > - if ((sizeof(dma_addr_t) < 8) && l) {
> > + if ((sizeof(pci_bus_addr_t) < 8) && l) {
> > /* Above 32-bit boundary; try to reallocate */
> > res->flags |= IORESOURCE_UNSET;
> > res->start = 0;
> > @@ -398,7 +398,7 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
> > struct pci_dev *dev = child->self;
> > u16 mem_base_lo, mem_limit_lo;
> > u64 base64, limit64;
> > - dma_addr_t base, limit;
> > + pci_bus_addr_t base, limit;
> > struct pci_bus_region region;
> > struct resource *res;
> >
> > @@ -425,8 +425,8 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
> > }
> > }
> >
> > - base = (dma_addr_t) base64;
> > - limit = (dma_addr_t) limit64;
> > + base = (pci_bus_addr_t) base64;
> > + limit = (pci_bus_addr_t) limit64;
> >
> > if (base != base64) {
> > dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
> > diff --git a/include/linux/pci.h b/include/linux/pci.h
> > index 211e9da..6021bbe 100644
> > --- a/include/linux/pci.h
> > +++ b/include/linux/pci.h
> > @@ -573,9 +573,15 @@ int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
> > int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
> > int reg, int len, u32 val);
> >
> > +#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
> > +typedef u64 pci_bus_addr_t;
> > +#else
> > +typedef u32 pci_bus_addr_t;
> > +#endif
> > +
> > struct pci_bus_region {
> > - dma_addr_t start;
> > - dma_addr_t end;
> > + pci_bus_addr_t start;
> > + pci_bus_addr_t end;
> > };
> >
> > struct pci_dynids {
> > @@ -1124,7 +1130,7 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
> >
> > int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
> >
> > -static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
> > +static inline pci_bus_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
> > {
> > struct pci_bus_region region;
> >
> > --
> > 1.8.4.5
> >

2015-04-04 03:34:56

by Yinghai Lu

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

On Fri, Apr 3, 2015 at 1:52 PM, Bjorn Helgaas <[email protected]> wrote:
> [+cc Sam (commented on previous versions), Russell, linux-arm-kernel, Ralf,
> linux-mips, Ben, linuxppc-dev, x86]
>
> On Fri, Apr 03, 2015 at 02:32:34PM -0500, Bjorn Helgaas wrote:
>> On Tue, Mar 31, 2015 at 07:57:47PM -0700, Yinghai Lu wrote:
>> > David Ahern found commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows
>> > to fit in upstream windows") broke booting on sparc/T5-8.
>> >
>> > In the boot log, there is
>> > pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address
>> > 0x110204000)
>> > but that only could happen when dma_addr_t is 32-bit.
>> >
>> > According to David Miller, all DMA occurs behind an IOMMU and these
>> > IOMMUs only support 32-bit addressing, therefore dma_addr_t is
>> > 32-bit on sparc64.
>> >
>> > Let's introduce pci_bus_addr_t instead of using dma_addr_t,
>> > and pci_bus_addr_t will be 64-bit on 64-bit platform or X86_PAE.
>> >
>> > Fixes: commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows")
>> > Fixes: commit 23b13bc76f35 ("PCI: Fail safely if we can't handle BARs larger than 4GB")
>> > Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
>> > Reported-by: David Ahern <[email protected]>
>> > Tested-by: David Ahern <[email protected]>
>> > Signed-off-by: Yinghai Lu <[email protected]>
>> > Cc: <[email protected]> #3.19
>> > ---
>> > drivers/pci/Kconfig | 4 ++++
>> > drivers/pci/bus.c | 10 +++++-----
>> > drivers/pci/probe.c | 12 ++++++------
>> > include/linux/pci.h | 12 +++++++++---
>> > 4 files changed, 24 insertions(+), 14 deletions(-)
>> >
>> > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
>> > index 7a8f1c5..6a5a269 100644
>> > --- a/drivers/pci/Kconfig
>> > +++ b/drivers/pci/Kconfig
>> > @@ -1,6 +1,10 @@
>> > #
>> > # PCI configuration
>> > #
>> > +config PCI_BUS_ADDR_T_64BIT
>> > + def_bool y if (64BIT || X86_PAE)
>> > + depends on PCI
>>
>> We're going to use pci_bus_addr_t in some places where we previously used
>> dma_addr_t, which means pci_bus_addr_t should be at least as large as
>> dma_addr_t. Can you enforce that directly, e.g., with something like this?
>>
>> def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT || X86_PAE)

then should use

def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT)

Thanks

Yinghai

2015-04-04 12:47:15

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

On Fri, Apr 3, 2015 at 10:34 PM, Yinghai Lu <[email protected]> wrote:
> On Fri, Apr 3, 2015 at 1:52 PM, Bjorn Helgaas <[email protected]> wrote:
>> [+cc Sam (commented on previous versions), Russell, linux-arm-kernel, Ralf,
>> linux-mips, Ben, linuxppc-dev, x86]
>>
>> On Fri, Apr 03, 2015 at 02:32:34PM -0500, Bjorn Helgaas wrote:
>>> On Tue, Mar 31, 2015 at 07:57:47PM -0700, Yinghai Lu wrote:
>>> > David Ahern found commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows
>>> > to fit in upstream windows") broke booting on sparc/T5-8.
>>> >
>>> > In the boot log, there is
>>> > pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address
>>> > 0x110204000)
>>> > but that only could happen when dma_addr_t is 32-bit.
>>> >
>>> > According to David Miller, all DMA occurs behind an IOMMU and these
>>> > IOMMUs only support 32-bit addressing, therefore dma_addr_t is
>>> > 32-bit on sparc64.
>>> >
>>> > Let's introduce pci_bus_addr_t instead of using dma_addr_t,
>>> > and pci_bus_addr_t will be 64-bit on 64-bit platform or X86_PAE.
>>> >
>>> > Fixes: commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows")
>>> > Fixes: commit 23b13bc76f35 ("PCI: Fail safely if we can't handle BARs larger than 4GB")
>>> > Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
>>> > Reported-by: David Ahern <[email protected]>
>>> > Tested-by: David Ahern <[email protected]>
>>> > Signed-off-by: Yinghai Lu <[email protected]>
>>> > Cc: <[email protected]> #3.19
>>> > ---
>>> > drivers/pci/Kconfig | 4 ++++
>>> > drivers/pci/bus.c | 10 +++++-----
>>> > drivers/pci/probe.c | 12 ++++++------
>>> > include/linux/pci.h | 12 +++++++++---
>>> > 4 files changed, 24 insertions(+), 14 deletions(-)
>>> >
>>> > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
>>> > index 7a8f1c5..6a5a269 100644
>>> > --- a/drivers/pci/Kconfig
>>> > +++ b/drivers/pci/Kconfig
>>> > @@ -1,6 +1,10 @@
>>> > #
>>> > # PCI configuration
>>> > #
>>> > +config PCI_BUS_ADDR_T_64BIT
>>> > + def_bool y if (64BIT || X86_PAE)
>>> > + depends on PCI
>>>
>>> We're going to use pci_bus_addr_t in some places where we previously used
>>> dma_addr_t, which means pci_bus_addr_t should be at least as large as
>>> dma_addr_t. Can you enforce that directly, e.g., with something like this?
>>>
>>> def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT || X86_PAE)
>
> then should use
>
> def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT)

OK, would you mind updating this series, incorporating the doc
updates, and reposting it?

I think there's still an unresolved question about the OF parsing code.

Bjorn

2015-04-04 19:49:24

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

On Sat, Apr 4, 2015 at 7:46 AM, Bjorn Helgaas <[email protected]> wrote:
> On Fri, Apr 3, 2015 at 10:34 PM, Yinghai Lu <[email protected]> wrote:
>> On Fri, Apr 3, 2015 at 1:52 PM, Bjorn Helgaas <[email protected]> wrote:
>>> [+cc Sam (commented on previous versions), Russell, linux-arm-kernel, Ralf,
>>> linux-mips, Ben, linuxppc-dev, x86]
>>>
>>> On Fri, Apr 03, 2015 at 02:32:34PM -0500, Bjorn Helgaas wrote:
>>>> On Tue, Mar 31, 2015 at 07:57:47PM -0700, Yinghai Lu wrote:
>>>> > David Ahern found commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows
>>>> > to fit in upstream windows") broke booting on sparc/T5-8.
>>>> >
>>>> > In the boot log, there is
>>>> > pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address
>>>> > 0x110204000)
>>>> > but that only could happen when dma_addr_t is 32-bit.
>>>> >
>>>> > According to David Miller, all DMA occurs behind an IOMMU and these
>>>> > IOMMUs only support 32-bit addressing, therefore dma_addr_t is
>>>> > 32-bit on sparc64.
>>>> >
>>>> > Let's introduce pci_bus_addr_t instead of using dma_addr_t,
>>>> > and pci_bus_addr_t will be 64-bit on 64-bit platform or X86_PAE.
>>>> >
>>>> > Fixes: commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows")
>>>> > Fixes: commit 23b13bc76f35 ("PCI: Fail safely if we can't handle BARs larger than 4GB")
>>>> > Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
>>>> > Reported-by: David Ahern <[email protected]>
>>>> > Tested-by: David Ahern <[email protected]>
>>>> > Signed-off-by: Yinghai Lu <[email protected]>
>>>> > Cc: <[email protected]> #3.19
>>>> > ---
>>>> > drivers/pci/Kconfig | 4 ++++
>>>> > drivers/pci/bus.c | 10 +++++-----
>>>> > drivers/pci/probe.c | 12 ++++++------
>>>> > include/linux/pci.h | 12 +++++++++---
>>>> > 4 files changed, 24 insertions(+), 14 deletions(-)
>>>> >
>>>> > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
>>>> > index 7a8f1c5..6a5a269 100644
>>>> > --- a/drivers/pci/Kconfig
>>>> > +++ b/drivers/pci/Kconfig
>>>> > @@ -1,6 +1,10 @@
>>>> > #
>>>> > # PCI configuration
>>>> > #
>>>> > +config PCI_BUS_ADDR_T_64BIT
>>>> > + def_bool y if (64BIT || X86_PAE)
>>>> > + depends on PCI
>>>>
>>>> We're going to use pci_bus_addr_t in some places where we previously used
>>>> dma_addr_t, which means pci_bus_addr_t should be at least as large as
>>>> dma_addr_t. Can you enforce that directly, e.g., with something like this?
>>>>
>>>> def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT || X86_PAE)
>>
>> then should use
>>
>> def_bool y if (ARCH_DMA_ADDR_T_64BIT || 64BIT)
>
> OK, would you mind updating this series, incorporating the doc
> updates, and reposting it?
>
> I think there's still an unresolved question about the OF parsing code.

Got a pointer to what that is? I'll take a guess. Generally, we make
the parsing code independent of the kernel addr sizes and use u64
types. The DT sizes and kernel sizes are not always aligned. For
example, an LPAE capable platform running a non-LPAE kernel build.

Rob

>
> Bjorn
>
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

2015-04-05 03:25:28

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

On Sat, Apr 4, 2015 at 2:48 PM, Rob Herring <[email protected]> wrote:
> On Sat, Apr 4, 2015 at 7:46 AM, Bjorn Helgaas <[email protected]> wrote:

>> I think there's still an unresolved question about the OF parsing code.
>
> Got a pointer to what that is? I'll take a guess. Generally, we make
> the parsing code independent of the kernel addr sizes and use u64
> types. The DT sizes and kernel sizes are not always aligned. For
> example, an LPAE capable platform running a non-LPAE kernel build.

Yep: http://lkml.kernel.org/r/[email protected]

Yinghai made a change to the sparc OF parsing code. The question is
whether a similar change should be made to clones of that code (two
others in arch/sparc, one in arch/powerpc, and one in drivers/of).

Bjorn

2015-04-06 13:05:58

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH 1/3] PCI: Introduce pci_bus_addr_t

On Sat, Apr 4, 2015 at 10:25 PM, Bjorn Helgaas <[email protected]> wrote:
> On Sat, Apr 4, 2015 at 2:48 PM, Rob Herring <[email protected]> wrote:
>> On Sat, Apr 4, 2015 at 7:46 AM, Bjorn Helgaas <[email protected]> wrote:
>
>>> I think there's still an unresolved question about the OF parsing code.
>>
>> Got a pointer to what that is? I'll take a guess. Generally, we make
>> the parsing code independent of the kernel addr sizes and use u64
>> types. The DT sizes and kernel sizes are not always aligned. For
>> example, an LPAE capable platform running a non-LPAE kernel build.
>
> Yep: http://lkml.kernel.org/r/[email protected]
>
> Yinghai made a change to the sparc OF parsing code. The question is
> whether a similar change should be made to clones of that code (two
> others in arch/sparc, one in arch/powerpc, and one in drivers/of).

Yes, it appears to me that is needed. At least the drivers/of/ code
does not distinguish 32 and 64 bit ATM.

Rob