Mailing List Archive

[PATCH v2 02/17] xen/pci: solve compilation error on ARM with HAS_PCI enabled
Compilation error is observed when HAS_PCI is enabled for ARM
architecture.

Add definition for arch_iommu_use_permitted() and
arch_pci_clean_pirqs().

pci.c: In function ‘deassign_device’:
pci.c:849:49: error: implicit declaration of function ‘pci_to_dev’;
did you mean ‘dt_to_dev’? [-Werror=implicit-function-declaration]
pci_to_dev(pdev));
pci.c:880: undefined reference to `arch_pci_clean_pirqs’
pci.c:1392: undefined reference to `arch_iommu_use_permitted'

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
---
Change in v2:
- Remove pci_conf_read*(..) dummy implementation
- Add in code comment for arch_pci_clean_pirqs() and arch_iommu_use_permitted()
- Fixed minor comments
---
xen/arch/arm/Makefile | 1 +
xen/arch/arm/pci/Makefile | 1 +
xen/arch/arm/pci/pci.c | 33 +++++++++++++++++++++++++++++
xen/drivers/passthrough/arm/iommu.c | 9 ++++++++
xen/include/asm-arm/pci.h | 31 ++++++++++++++++++++++++---
5 files changed, 72 insertions(+), 3 deletions(-)
create mode 100644 xen/arch/arm/pci/Makefile
create mode 100644 xen/arch/arm/pci/pci.c

diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index 3d3b97b5b4..44d7cc81fa 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_ARM_32) += arm32/
obj-$(CONFIG_ARM_64) += arm64/
obj-$(CONFIG_ARM_64) += efi/
obj-$(CONFIG_ACPI) += acpi/
+obj-$(CONFIG_HAS_PCI) += pci/
ifneq ($(CONFIG_NO_PLAT),y)
obj-y += platforms/
endif
diff --git a/xen/arch/arm/pci/Makefile b/xen/arch/arm/pci/Makefile
new file mode 100644
index 0000000000..a98035df4c
--- /dev/null
+++ b/xen/arch/arm/pci/Makefile
@@ -0,0 +1 @@
+obj-y += pci.o
diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
new file mode 100644
index 0000000000..a7a7bc3213
--- /dev/null
+++ b/xen/arch/arm/pci/pci.c
@@ -0,0 +1,33 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <xen/pci.h>
+
+/*
+ * PIRQ event channels are not supported on Arm, so nothing to do.
+ */
+int arch_pci_clean_pirqs(struct domain *d)
+{
+ return 0;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/drivers/passthrough/arm/iommu.c b/xen/drivers/passthrough/arm/iommu.c
index db3b07a571..ee653a9c48 100644
--- a/xen/drivers/passthrough/arm/iommu.c
+++ b/xen/drivers/passthrough/arm/iommu.c
@@ -135,3 +135,12 @@ void arch_iommu_domain_destroy(struct domain *d)
void __hwdom_init arch_iommu_hwdom_init(struct domain *d)
{
}
+
+/*
+ * Unlike x86, Arm doesn't support mem-sharing, mem-paging and log-dirty (yet).
+ * So there is no restriction to use the IOMMU.
+ */
+bool arch_iommu_use_permitted(const struct domain *d)
+{
+ return true;
+}
diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
index de13359f65..7dd9eb3dba 100644
--- a/xen/include/asm-arm/pci.h
+++ b/xen/include/asm-arm/pci.h
@@ -1,7 +1,32 @@
-#ifndef __X86_PCI_H__
-#define __X86_PCI_H__
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */

+#ifndef __ARM_PCI_H__
+#define __ARM_PCI_H__
+
+#ifdef CONFIG_HAS_PCI
+
+#define pci_to_dev(pcidev) (&(pcidev)->arch.dev)
+
+/* Arch pci dev struct */
struct arch_pci_dev {
+ struct device dev;
};

-#endif /* __X86_PCI_H__ */
+#else /*!CONFIG_HAS_PCI*/
+
+struct arch_pci_dev { };
+
+#endif /*!CONFIG_HAS_PCI*/
+#endif /* __ARM_PCI_H__ */
--
2.17.1
Re: [PATCH v2 02/17] xen/pci: solve compilation error on ARM with HAS_PCI enabled [ In reply to ]
On Wed, 22 Sep 2021, Rahul Singh wrote:
> Compilation error is observed when HAS_PCI is enabled for ARM
> architecture.
>
> Add definition for arch_iommu_use_permitted() and
> arch_pci_clean_pirqs().
>
> pci.c: In function ‘deassign_device’:
> pci.c:849:49: error: implicit declaration of function ‘pci_to_dev’;
> did you mean ‘dt_to_dev’? [-Werror=implicit-function-declaration]
> pci_to_dev(pdev));
> pci.c:880: undefined reference to `arch_pci_clean_pirqs’
> pci.c:1392: undefined reference to `arch_iommu_use_permitted'
>
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
> Change in v2:
> - Remove pci_conf_read*(..) dummy implementation
> - Add in code comment for arch_pci_clean_pirqs() and arch_iommu_use_permitted()
> - Fixed minor comments
> ---
> xen/arch/arm/Makefile | 1 +
> xen/arch/arm/pci/Makefile | 1 +
> xen/arch/arm/pci/pci.c | 33 +++++++++++++++++++++++++++++
> xen/drivers/passthrough/arm/iommu.c | 9 ++++++++
> xen/include/asm-arm/pci.h | 31 ++++++++++++++++++++++++---
> 5 files changed, 72 insertions(+), 3 deletions(-)
> create mode 100644 xen/arch/arm/pci/Makefile
> create mode 100644 xen/arch/arm/pci/pci.c
>
> diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
> index 3d3b97b5b4..44d7cc81fa 100644
> --- a/xen/arch/arm/Makefile
> +++ b/xen/arch/arm/Makefile
> @@ -2,6 +2,7 @@ obj-$(CONFIG_ARM_32) += arm32/
> obj-$(CONFIG_ARM_64) += arm64/
> obj-$(CONFIG_ARM_64) += efi/
> obj-$(CONFIG_ACPI) += acpi/
> +obj-$(CONFIG_HAS_PCI) += pci/
> ifneq ($(CONFIG_NO_PLAT),y)
> obj-y += platforms/
> endif
> diff --git a/xen/arch/arm/pci/Makefile b/xen/arch/arm/pci/Makefile
> new file mode 100644
> index 0000000000..a98035df4c
> --- /dev/null
> +++ b/xen/arch/arm/pci/Makefile
> @@ -0,0 +1 @@
> +obj-y += pci.o
> diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
> new file mode 100644
> index 0000000000..a7a7bc3213
> --- /dev/null
> +++ b/xen/arch/arm/pci/pci.c
> @@ -0,0 +1,33 @@
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <xen/pci.h>
> +
> +/*
> + * PIRQ event channels are not supported on Arm, so nothing to do.
> + */
> +int arch_pci_clean_pirqs(struct domain *d)
> +{
> + return 0;
> +}
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * tab-width: 4
> + * indent-tabs-mode: nil
> + * End:
> + */
> diff --git a/xen/drivers/passthrough/arm/iommu.c b/xen/drivers/passthrough/arm/iommu.c
> index db3b07a571..ee653a9c48 100644
> --- a/xen/drivers/passthrough/arm/iommu.c
> +++ b/xen/drivers/passthrough/arm/iommu.c
> @@ -135,3 +135,12 @@ void arch_iommu_domain_destroy(struct domain *d)
> void __hwdom_init arch_iommu_hwdom_init(struct domain *d)
> {
> }
> +
> +/*
> + * Unlike x86, Arm doesn't support mem-sharing, mem-paging and log-dirty (yet).
> + * So there is no restriction to use the IOMMU.
> + */
> +bool arch_iommu_use_permitted(const struct domain *d)
> +{
> + return true;
> +}
> diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
> index de13359f65..7dd9eb3dba 100644
> --- a/xen/include/asm-arm/pci.h
> +++ b/xen/include/asm-arm/pci.h
> @@ -1,7 +1,32 @@
> -#ifndef __X86_PCI_H__
> -#define __X86_PCI_H__
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
>
> +#ifndef __ARM_PCI_H__
> +#define __ARM_PCI_H__
> +
> +#ifdef CONFIG_HAS_PCI
> +
> +#define pci_to_dev(pcidev) (&(pcidev)->arch.dev)
> +
> +/* Arch pci dev struct */
> struct arch_pci_dev {
> + struct device dev;
> };
>
> -#endif /* __X86_PCI_H__ */
> +#else /*!CONFIG_HAS_PCI*/
> +
> +struct arch_pci_dev { };
> +
> +#endif /*!CONFIG_HAS_PCI*/
> +#endif /* __ARM_PCI_H__ */
> --
> 2.17.1
>
Re: [PATCH v2 02/17] xen/pci: solve compilation error on ARM with HAS_PCI enabled [ In reply to ]
Hi,

On Wed, 22 Sep 2021, 16:36 Rahul Singh, <rahul.singh@arm.com> wrote:

> Compilation error is observed when HAS_PCI is enabled for ARM
> architecture.


In general, when I read "compilation error" I interpret as a user can
trigger it in the current staging.

However, without the full series applied, HAS_PCI cannot be selected on Arm.

So I think the message is a bit misleading because this is more
implementing stubs to enable a feature rather than fixing compilation
errors (AFAICT all of them are not fixed here).

How about the following commit message:

xen/arm: pci: Add stubs to allow selecting HAS_PCI

In a follow-up we will enable PCI support in Xen on Arm (i.e select
HAS_PCI).

The generic code expects the arch to implement a few functions:

<List the functions>

Note that this is not yet sufficient to enable HAS_PCI and will be
addressed in follow-ups.


> Add definition for arch_iommu_use_permitted() and
> arch_pci_clean_pirqs().
>
> pci.c: In function ‘deassign_device’:
> pci.c:849:49: error: implicit declaration of function ‘pci_to_dev’;
> did you mean ‘dt_to_dev’? [-Werror=implicit-function-declaration]
> pci_to_dev(pdev));
> pci.c:880: undefined reference to `arch_pci_clean_pirqs’
> pci.c:1392: undefined reference to `arch_iommu_use_permitted'
>
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
> ---
> Change in v2:
> - Remove pci_conf_read*(..) dummy implementation
> - Add in code comment for arch_pci_clean_pirqs() and
> arch_iommu_use_permitted()
> - Fixed minor comments
> ---
> xen/arch/arm/Makefile | 1 +
> xen/arch/arm/pci/Makefile | 1 +
> xen/arch/arm/pci/pci.c | 33 +++++++++++++++++++++++++++++
> xen/drivers/passthrough/arm/iommu.c | 9 ++++++++
> xen/include/asm-arm/pci.h | 31 ++++++++++++++++++++++++---
> 5 files changed, 72 insertions(+), 3 deletions(-)
> create mode 100644 xen/arch/arm/pci/Makefile
> create mode 100644 xen/arch/arm/pci/pci.c
>
> diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
> index 3d3b97b5b4..44d7cc81fa 100644
> --- a/xen/arch/arm/Makefile
> +++ b/xen/arch/arm/Makefile
> @@ -2,6 +2,7 @@ obj-$(CONFIG_ARM_32) += arm32/
> obj-$(CONFIG_ARM_64) += arm64/
> obj-$(CONFIG_ARM_64) += efi/
> obj-$(CONFIG_ACPI) += acpi/
> +obj-$(CONFIG_HAS_PCI) += pci/
> ifneq ($(CONFIG_NO_PLAT),y)
> obj-y += platforms/
> endif
> diff --git a/xen/arch/arm/pci/Makefile b/xen/arch/arm/pci/Makefile
> new file mode 100644
> index 0000000000..a98035df4c
> --- /dev/null
> +++ b/xen/arch/arm/pci/Makefile
> @@ -0,0 +1 @@
> +obj-y += pci.o
> diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
> new file mode 100644
> index 0000000000..a7a7bc3213
> --- /dev/null
> +++ b/xen/arch/arm/pci/pci.c
> @@ -0,0 +1,33 @@
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <xen/pci.h>
> +
> +/*
> + * PIRQ event channels are not supported on Arm, so nothing to do.
> + */
> +int arch_pci_clean_pirqs(struct domain *d)
> +{
> + return 0;
> +}
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * tab-width: 4
> + * indent-tabs-mode: nil
> + * End:
> + */
> diff --git a/xen/drivers/passthrough/arm/iommu.c
> b/xen/drivers/passthrough/arm/iommu.c
> index db3b07a571..ee653a9c48 100644
> --- a/xen/drivers/passthrough/arm/iommu.c
> +++ b/xen/drivers/passthrough/arm/iommu.c
> @@ -135,3 +135,12 @@ void arch_iommu_domain_destroy(struct domain *d)
> void __hwdom_init arch_iommu_hwdom_init(struct domain *d)
> {
> }
> +
> +/*
> + * Unlike x86, Arm doesn't support mem-sharing, mem-paging and log-dirty
> (yet).
> + * So there is no restriction to use the IOMMU.
> + */
> +bool arch_iommu_use_permitted(const struct domain *d)
> +{
> + return true;
> +}
> diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
> index de13359f65..7dd9eb3dba 100644
> --- a/xen/include/asm-arm/pci.h
> +++ b/xen/include/asm-arm/pci.h
> @@ -1,7 +1,32 @@
> -#ifndef __X86_PCI_H__
> -#define __X86_PCI_H__
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
>
> +#ifndef __ARM_PCI_H__
> +#define __ARM_PCI_H__
> +
> +#ifdef CONFIG_HAS_PCI
> +
> +#define pci_to_dev(pcidev) (&(pcidev)->arch.dev)
> +
> +/* Arch pci dev struct */
> struct arch_pci_dev {
> + struct device dev;
> };
>
> -#endif /* __X86_PCI_H__ */
> +#else /*!CONFIG_HAS_PCI*/
> +
> +struct arch_pci_dev { };
> +
> +#endif /*!CONFIG_HAS_PCI*/
> +#endif /* __ARM_PCI_H__ */
> --
> 2.17.1
>
>
Re: [PATCH v2 02/17] xen/pci: solve compilation error on ARM with HAS_PCI enabled [ In reply to ]
Hi Julien

> On 23 Sep 2021, at 3:07 am, Julien Grall <julien.grall.oss@gmail.com> wrote:
>
> Hi,
>
> On Wed, 22 Sep 2021, 16:36 Rahul Singh, <rahul.singh@arm.com> wrote:
> Compilation error is observed when HAS_PCI is enabled for ARM
> architecture.
>
> In general, when I read "compilation error" I interpret as a user can trigger it in the current staging.
>
> However, without the full series applied, HAS_PCI cannot be selected on Arm.
>
> So I think the message is a bit misleading because this is more implementing stubs to enable a feature rather than fixing compilation errors (AFAICT all of them are not fixed here).
>
> How about the following commit message:
>
> xen/arm: pci: Add stubs to allow selecting HAS_PCI
>
> In a follow-up we will enable PCI support in Xen on Arm (i.e select HAS_PCI).
>
> The generic code expects the arch to implement a few functions:
>
> <List the functions>
>
> Note that this is not yet sufficient to enable HAS_PCI and will be addressed in follow-ups.
>

Ok. I will modify the commit message in next version.

Regards,
Rahul