* Re: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
2019-09-30 12:14 ` [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks Arnd Bergmann
@ 2019-09-30 13:04 ` Bjorn Helgaas
2019-10-10 12:55 ` Herbert Xu
2019-10-17 13:26 ` Pascal Van Leeuwen
2 siblings, 0 replies; 6+ messages in thread
From: Bjorn Helgaas @ 2019-09-30 13:04 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Antoine Tenart, Herbert Xu, David S. Miller, Pascal van Leeuwen,
Pascal van Leeuwen, Kelsey Skunberg, linux-crypto, linux-kernel,
linux-pci
On Mon, Sep 30, 2019 at 02:14:35PM +0200, Arnd Bergmann wrote:
> When both PCI and OF are disabled, no drivers are registered, and
> we get some unused-function warnings:
>
> drivers/crypto/inside-secure/safexcel.c:1221:13: error: unused function 'safexcel_unregister_algorithms' [-Werror,-Wunused-function]
> static void safexcel_unregister_algorithms(struct safexcel_crypto_priv *priv)
> drivers/crypto/inside-secure/safexcel.c:1307:12: error: unused function 'safexcel_probe_generic' [-Werror,-Wunused-function]
> static int safexcel_probe_generic(void *pdev,
> drivers/crypto/inside-secure/safexcel.c:1531:13: error: unused function 'safexcel_hw_reset_rings' [-Werror,-Wunused-function]
> static void safexcel_hw_reset_rings(struct safexcel_crypto_priv *priv)
>
> It's better to make the compiler see what is going on and remove
> such ifdef checks completely. In case of PCI, this is trivial since
> pci_register_driver() is defined to an empty function that makes the
> compiler subsequently drop all unused code silently.
>
> The global pcireg_rc/ofreg_rc variables are not actually needed here
> since the driver registration does not fail in ways that would make
> it helpful.
>
> For CONFIG_OF, an IS_ENABLED() check is still required, since platform
> drivers can exist both with and without it.
>
> A little change to linux/pci.h is needed to ensure that
> pcim_enable_device() is visible to the driver. Moving the declaration
> outside of ifdef would be sufficient here, but for consistency with the
> rest of the file, adding an inline helper is probably best.
>
> Fixes: 212ef6f29e5b ("crypto: inside-secure - Fix unused variable warning when CONFIG_PCI=n")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/crypto/inside-secure/safexcel.c | 49 ++++++-------------------
> include/linux/pci.h | 1 +
> 2 files changed, 13 insertions(+), 37 deletions(-)
> ...
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index f9088c89a534..1a6cf19eac2d 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1686,6 +1686,7 @@ static inline struct pci_dev *pci_get_class(unsigned int class,
> static inline void pci_set_master(struct pci_dev *dev) { }
> static inline int pci_enable_device(struct pci_dev *dev) { return -EIO; }
> static inline void pci_disable_device(struct pci_dev *dev) { }
> +static inline int pcim_enable_device(struct pci_dev *pdev) { return -EIO; }
I would have used "dev" here to match surrounding stubs, but either
way:
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci.h
> static inline int pci_assign_resource(struct pci_dev *dev, int i)
> { return -EBUSY; }
> static inline int __pci_register_driver(struct pci_driver *drv,
> --
> 2.20.0
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
2019-09-30 12:14 ` [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks Arnd Bergmann
2019-09-30 13:04 ` Bjorn Helgaas
@ 2019-10-10 12:55 ` Herbert Xu
2019-10-17 13:26 ` Pascal Van Leeuwen
2 siblings, 0 replies; 6+ messages in thread
From: Herbert Xu @ 2019-10-10 12:55 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Antoine Tenart, David S. Miller, Bjorn Helgaas,
Pascal van Leeuwen, Pascal van Leeuwen, Kelsey Skunberg,
linux-crypto, linux-kernel, linux-pci
On Mon, Sep 30, 2019 at 02:14:35PM +0200, Arnd Bergmann wrote:
> When both PCI and OF are disabled, no drivers are registered, and
> we get some unused-function warnings:
>
> drivers/crypto/inside-secure/safexcel.c:1221:13: error: unused function 'safexcel_unregister_algorithms' [-Werror,-Wunused-function]
> static void safexcel_unregister_algorithms(struct safexcel_crypto_priv *priv)
> drivers/crypto/inside-secure/safexcel.c:1307:12: error: unused function 'safexcel_probe_generic' [-Werror,-Wunused-function]
> static int safexcel_probe_generic(void *pdev,
> drivers/crypto/inside-secure/safexcel.c:1531:13: error: unused function 'safexcel_hw_reset_rings' [-Werror,-Wunused-function]
> static void safexcel_hw_reset_rings(struct safexcel_crypto_priv *priv)
>
> It's better to make the compiler see what is going on and remove
> such ifdef checks completely. In case of PCI, this is trivial since
> pci_register_driver() is defined to an empty function that makes the
> compiler subsequently drop all unused code silently.
>
> The global pcireg_rc/ofreg_rc variables are not actually needed here
> since the driver registration does not fail in ways that would make
> it helpful.
>
> For CONFIG_OF, an IS_ENABLED() check is still required, since platform
> drivers can exist both with and without it.
>
> A little change to linux/pci.h is needed to ensure that
> pcim_enable_device() is visible to the driver. Moving the declaration
> outside of ifdef would be sufficient here, but for consistency with the
> rest of the file, adding an inline helper is probably best.
>
> Fixes: 212ef6f29e5b ("crypto: inside-secure - Fix unused variable warning when CONFIG_PCI=n")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/crypto/inside-secure/safexcel.c | 49 ++++++-------------------
> include/linux/pci.h | 1 +
> 2 files changed, 13 insertions(+), 37 deletions(-)
Patch applied. Thanks.
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
^ permalink raw reply [flat|nested] 6+ messages in thread* RE: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
2019-09-30 12:14 ` [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks Arnd Bergmann
2019-09-30 13:04 ` Bjorn Helgaas
2019-10-10 12:55 ` Herbert Xu
@ 2019-10-17 13:26 ` Pascal Van Leeuwen
2019-10-17 13:47 ` Arnd Bergmann
2 siblings, 1 reply; 6+ messages in thread
From: Pascal Van Leeuwen @ 2019-10-17 13:26 UTC (permalink / raw)
To: Arnd Bergmann, Antoine Tenart, Herbert Xu, David S. Miller,
Bjorn Helgaas
Cc: Pascal van Leeuwen, Kelsey Skunberg, linux-crypto, linux-kernel,
linux-pci
Hi Arnd,
Sorry for not responding earlier, but I've been very busy lately.
So I'm looking at this now for the first time.
> -----Original Message-----
> From: Arnd Bergmann <arnd@arndb.de>
> Sent: Monday, September 30, 2019 2:15 PM
> To: Antoine Tenart <antoine.tenart@bootlin.com>; Herbert Xu <herbert@gondor.apana.org.au>;
> David S. Miller <davem@davemloft.net>; Bjorn Helgaas <bhelgaas@google.com>
> Cc: Arnd Bergmann <arnd@arndb.de>; Pascal Van Leeuwen <pvanleeuwen@verimatrix.com>; Pascal van
> Leeuwen <pascalvanl@gmail.com>; Kelsey Skunberg <skunberg.kelsey@gmail.com>; linux-
> crypto@vger.kernel.org; linux-kernel@vger.kernel.org; linux-pci@vger.kernel.org
> Subject: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
>
> When both PCI and OF are disabled, no drivers are registered, and
> we get some unused-function warnings:
>
> drivers/crypto/inside-secure/safexcel.c:1221:13: error: unused function
> 'safexcel_unregister_algorithms' [-Werror,-Wunused-function]
> static void safexcel_unregister_algorithms(struct safexcel_crypto_priv *priv)
> drivers/crypto/inside-secure/safexcel.c:1307:12: error: unused function
> 'safexcel_probe_generic' [-Werror,-Wunused-function]
> static int safexcel_probe_generic(void *pdev,
> drivers/crypto/inside-secure/safexcel.c:1531:13: error: unused function
> 'safexcel_hw_reset_rings' [-Werror,-Wunused-function]
> static void safexcel_hw_reset_rings(struct safexcel_crypto_priv *priv)
>
> It's better to make the compiler see what is going on and remove
> such ifdef checks completely. In case of PCI, this is trivial since
> pci_register_driver() is defined to an empty function that makes the
> compiler subsequently drop all unused code silently.
>
> The global pcireg_rc/ofreg_rc variables are not actually needed here
> since the driver registration does not fail in ways that would make
> it helpful.
>
> For CONFIG_OF, an IS_ENABLED() check is still required, since platform
> drivers can exist both with and without it.
>
> A little change to linux/pci.h is needed to ensure that
> pcim_enable_device() is visible to the driver. Moving the declaration
> outside of ifdef would be sufficient here, but for consistency with the
> rest of the file, adding an inline helper is probably best.
>
> Fixes: 212ef6f29e5b ("crypto: inside-secure - Fix unused variable warning when CONFIG_PCI=n")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/crypto/inside-secure/safexcel.c | 49 ++++++-------------------
> include/linux/pci.h | 1 +
> 2 files changed, 13 insertions(+), 37 deletions(-)
>
> diff --git a/drivers/crypto/inside-secure/safexcel.c b/drivers/crypto/inside-secure/safexcel.c
> index 311bf60df39f..c4e8fd27314c 100644
> --- a/drivers/crypto/inside-secure/safexcel.c
> +++ b/drivers/crypto/inside-secure/safexcel.c
> @@ -1547,7 +1547,6 @@ static void safexcel_hw_reset_rings(struct safexcel_crypto_priv *priv)
> }
> }
>
> -#if IS_ENABLED(CONFIG_OF)
> /* for Device Tree platform driver */
>
> static int safexcel_probe(struct platform_device *pdev)
> @@ -1666,9 +1665,7 @@ static struct platform_driver crypto_safexcel = {
> .of_match_table = safexcel_of_match_table,
> },
> };
> -#endif
>
> -#if IS_ENABLED(CONFIG_PCI)
> /* PCIE devices - i.e. Inside Secure development boards */
>
> static int safexcel_pci_probe(struct pci_dev *pdev,
> @@ -1789,54 +1786,32 @@ static struct pci_driver safexcel_pci_driver = {
> .probe = safexcel_pci_probe,
> .remove = safexcel_pci_remove,
> };
> -#endif
> -
> -/* Unfortunately, we have to resort to global variables here */
> -#if IS_ENABLED(CONFIG_PCI)
> -int pcireg_rc = -EINVAL; /* Default safe value */
> -#endif
> -#if IS_ENABLED(CONFIG_OF)
> -int ofreg_rc = -EINVAL; /* Default safe value */
> -#endif
>
> static int __init safexcel_init(void)
> {
> -#if IS_ENABLED(CONFIG_PCI)
> + int ret;
> +
> /* Register PCI driver */
> - pcireg_rc = pci_register_driver(&safexcel_pci_driver);
> -#endif
> + ret = pci_register_driver(&safexcel_pci_driver);
>
> -#if IS_ENABLED(CONFIG_OF)
> /* Register platform driver */
> - ofreg_rc = platform_driver_register(&crypto_safexcel);
> - #if IS_ENABLED(CONFIG_PCI)
> - /* Return success if either PCI or OF registered OK */
> - return pcireg_rc ? ofreg_rc : 0;
> - #else
> - return ofreg_rc;
> - #endif
> -#else
> - #if IS_ENABLED(CONFIG_PCI)
> - return pcireg_rc;
> - #else
> - return -EINVAL;
> - #endif
> -#endif
> + if (IS_ENABLED(CONFIG_OF) && !ret) {
>
Hmm ... this would make it skip the OF registration if the PCIE
registration failed. Note that the typical embedded system will
have a PCIE subsystem (e.g. Marvell A7K/A8K does) but will have
the EIP embedded on the SoC as an OF device.
So the question is: is it possible somehow that PCIE registration
fails while OF registration does pass? Because in that case, this
code would be wrong ...
Other than that, I don't care much how this code is implemented
as long as it works for both my use cases, being an OF embedded
device (on a SoC _with_ or _without_ PCIE support) and a device
on a PCIE board in a PCI (which has both PCIE and OF support).
> + ret = platform_driver_register(&crypto_safexcel);
> + if (ret)
> + pci_unregister_driver(&safexcel_pci_driver);
> + }
> +
> + return ret;
> }
>
> static void __exit safexcel_exit(void)
> {
> -#if IS_ENABLED(CONFIG_OF)
> /* Unregister platform driver */
> - if (!ofreg_rc)
> + if (IS_ENABLED(CONFIG_OF))
> platform_driver_unregister(&crypto_safexcel);
> -#endif
>
> -#if IS_ENABLED(CONFIG_PCI)
> /* Unregister PCI driver if successfully registered before */
> - if (!pcireg_rc)
> - pci_unregister_driver(&safexcel_pci_driver);
> -#endif
> + pci_unregister_driver(&safexcel_pci_driver);
> }
>
> module_init(safexcel_init);
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index f9088c89a534..1a6cf19eac2d 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1686,6 +1686,7 @@ static inline struct pci_dev *pci_get_class(unsigned int class,
> static inline void pci_set_master(struct pci_dev *dev) { }
> static inline int pci_enable_device(struct pci_dev *dev) { return -EIO; }
> static inline void pci_disable_device(struct pci_dev *dev) { }
> +static inline int pcim_enable_device(struct pci_dev *pdev) { return -EIO; }
> static inline int pci_assign_resource(struct pci_dev *dev, int i)
> { return -EBUSY; }
> static inline int __pci_register_driver(struct pci_driver *drv,
> --
> 2.20.0
Regards,
Pascal van Leeuwen
Silicon IP Architect, Multi-Protocol Engines @ Verimatrix
www.insidesecure.com
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
2019-10-17 13:26 ` Pascal Van Leeuwen
@ 2019-10-17 13:47 ` Arnd Bergmann
2019-10-17 14:14 ` Pascal Van Leeuwen
0 siblings, 1 reply; 6+ messages in thread
From: Arnd Bergmann @ 2019-10-17 13:47 UTC (permalink / raw)
To: Pascal Van Leeuwen
Cc: Antoine Tenart, Herbert Xu, David S. Miller, Bjorn Helgaas,
Pascal van Leeuwen, Kelsey Skunberg, linux-crypto, linux-kernel,
linux-pci
On Thu, Oct 17, 2019 at 3:26 PM Pascal Van Leeuwen
<pvanleeuwen@verimatrix.com> wrote:
> > /* Register PCI driver */
> > - pcireg_rc = pci_register_driver(&safexcel_pci_driver);
> > -#endif
> > + ret = pci_register_driver(&safexcel_pci_driver);
> >
> > -#if IS_ENABLED(CONFIG_OF)
> > /* Register platform driver */
> > - ofreg_rc = platform_driver_register(&crypto_safexcel);
> > - #if IS_ENABLED(CONFIG_PCI)
> > - /* Return success if either PCI or OF registered OK */
> > - return pcireg_rc ? ofreg_rc : 0;
> > - #else
> > - return ofreg_rc;
> > - #endif
> > -#else
> > - #if IS_ENABLED(CONFIG_PCI)
> > - return pcireg_rc;
> > - #else
> > - return -EINVAL;
> > - #endif
> > -#endif
> > + if (IS_ENABLED(CONFIG_OF) && !ret) {
> >
> Hmm ... this would make it skip the OF registration if the PCIE
> registration failed. Note that the typical embedded system will
> have a PCIE subsystem (e.g. Marvell A7K/A8K does) but will have
> the EIP embedded on the SoC as an OF device.
>
> So the question is: is it possible somehow that PCIE registration
> fails while OF registration does pass? Because in that case, this
> code would be wrong ...
I don't see how it would fail. When CONFIG_PCI is disabled,
pci_register_driver() does nothing, and the pci_driver as well
as everything referenced from it will be silently dropped from
the object file.
If CONFIG_PCI is enabled, then the driver will be registered
to the PCI subsystem, waiting for a device to show up, but
the driver registration does not care about whether there is
such a device.
> Other than that, I don't care much how this code is implemented
> as long as it works for both my use cases, being an OF embedded
> device (on a SoC _with_ or _without_ PCIE support) and a device
> on a PCIE board in a PCI (which has both PCIE and OF support).
Yes, that should be fine. There are a lot of drivers that support
multiple bus interfaces, and this is the normal way to handle them.
Arnd
^ permalink raw reply [flat|nested] 6+ messages in thread* RE: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
2019-10-17 13:47 ` Arnd Bergmann
@ 2019-10-17 14:14 ` Pascal Van Leeuwen
0 siblings, 0 replies; 6+ messages in thread
From: Pascal Van Leeuwen @ 2019-10-17 14:14 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Antoine Tenart, Herbert Xu, David S. Miller, Bjorn Helgaas,
Pascal van Leeuwen, Kelsey Skunberg, linux-crypto, linux-kernel,
linux-pci
> -----Original Message-----
> From: Arnd Bergmann <arnd@arndb.de>
> Sent: Thursday, October 17, 2019 3:48 PM
> To: Pascal Van Leeuwen <pvanleeuwen@verimatrix.com>
> Cc: Antoine Tenart <antoine.tenart@bootlin.com>; Herbert Xu <herbert@gondor.apana.org.au>;
> David S. Miller <davem@davemloft.net>; Bjorn Helgaas <bhelgaas@google.com>; Pascal van Leeuwen
> <pascalvanl@gmail.com>; Kelsey Skunberg <skunberg.kelsey@gmail.com>; linux-
> crypto@vger.kernel.org; linux-kernel@vger.kernel.org; linux-pci@vger.kernel.org
> Subject: Re: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks
>
> On Thu, Oct 17, 2019 at 3:26 PM Pascal Van Leeuwen
> <pvanleeuwen@verimatrix.com> wrote:
>
> > > /* Register PCI driver */
> > > - pcireg_rc = pci_register_driver(&safexcel_pci_driver);
> > > -#endif
> > > + ret = pci_register_driver(&safexcel_pci_driver);
> > >
> > > -#if IS_ENABLED(CONFIG_OF)
> > > /* Register platform driver */
> > > - ofreg_rc = platform_driver_register(&crypto_safexcel);
> > > - #if IS_ENABLED(CONFIG_PCI)
> > > - /* Return success if either PCI or OF registered OK */
> > > - return pcireg_rc ? ofreg_rc : 0;
> > > - #else
> > > - return ofreg_rc;
> > > - #endif
> > > -#else
> > > - #if IS_ENABLED(CONFIG_PCI)
> > > - return pcireg_rc;
> > > - #else
> > > - return -EINVAL;
> > > - #endif
> > > -#endif
> > > + if (IS_ENABLED(CONFIG_OF) && !ret) {
> > >
> > Hmm ... this would make it skip the OF registration if the PCIE
> > registration failed. Note that the typical embedded system will
> > have a PCIE subsystem (e.g. Marvell A7K/A8K does) but will have
> > the EIP embedded on the SoC as an OF device.
> >
> > So the question is: is it possible somehow that PCIE registration
> > fails while OF registration does pass? Because in that case, this
> > code would be wrong ...
>
> I don't see how it would fail. When CONFIG_PCI is disabled,
> pci_register_driver() does nothing, and the pci_driver as well
> as everything referenced from it will be silently dropped from
> the object file.
> If CONFIG_PCI is enabled, then the driver will be registered
> to the PCI subsystem, waiting for a device to show up, but
> the driver registration does not care about whether there is
> such a device.
>
I know it does not care about the device being present or not.
I was just worried some issue with the PCIE subsystem would propagate
to (unrelated) OF device use this way. But I have no idea on the exact
ways PCIE registration may fail. If it is because of lack of memory,
I assume that subsequent OF device registration would fail as well.
So maybe I'm worried about an issue that doesn't really exist.
> > Other than that, I don't care much how this code is implemented
> > as long as it works for both my use cases, being an OF embedded
> > device (on a SoC _with_ or _without_ PCIE support) and a device
> > on a PCIE board in a PCI (which has both PCIE and OF support).
>
> Yes, that should be fine. There are a lot of drivers that support
> multiple bus interfaces, and this is the normal way to handle them.
>
Ok, if this is the "normal way to handle this" and a lot of other
drivers do it the same way, then I'm OK with that ...
I already verified it works correctly for my specific use cases.
Thanks.
> Arnd
Regards,
Pascal van Leeuwen
Silicon IP Architect, Multi-Protocol Engines @ Verimatrix
www.insidesecure.com
^ permalink raw reply [flat|nested] 6+ messages in thread