| Message ID | 20220616154130.2052541-1-stefanb@linux.ibm.com |
|---|---|
| Headers | show |
| Series | tpm: Preserve TPM measurement log across kexec | expand |
On Thu, Jun 16, 2022 at 11:41:28AM -0400, Stefan Berger wrote: > Simplify tpm_read_log_of() by moving Openfirmware-specific code into > the Openfirmware driver to make the code reusable. Call the new There is no such 'Openfirmware driver'. > of_tpm_get_sml_parameters() function from the TPM Openfirmware driver. > > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> > Cc: Jarkko Sakkinen <jarkko@kernel.org> > Cc: Jason Gunthorpe <jgg@ziepe.ca> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Frank Rowand <frowand.list@gmail.com> > --- > drivers/char/tpm/eventlog/of.c | 31 +++++-------------------------- > drivers/of/Makefile | 2 +- > drivers/of/device_node.c | 27 +++++++++++++++++++++++++++ Humm, definitely the wrong direction. Generally, code for specific bindings does not go in drivers/of/. There used to be some, but we've moved it to the appropriate subsystems. kexec was an exception to not have 2 copies of the same code in arch/. > include/linux/of_device_node.h | 9 +++++++++ of_tpm.h would be the right name assuming we kept this structure which we shouldn't. Probably linux/tpm.h? Just a guess, I'm not familar with the TPM code really. > 4 files changed, 42 insertions(+), 27 deletions(-) > create mode 100644 drivers/of/device_node.c > create mode 100644 include/linux/of_device_node.h > > diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c > index a9ce66d09a75..5b18f4333ad1 100644 > --- a/drivers/char/tpm/eventlog/of.c > +++ b/drivers/char/tpm/eventlog/of.c > @@ -12,6 +12,7 @@ > > #include <linux/slab.h> > #include <linux/of.h> > +#include <linux/of_device_node.h> > #include <linux/tpm_eventlog.h> > > #include "../tpm.h" > @@ -20,11 +21,10 @@ > int tpm_read_log_of(struct tpm_chip *chip) > { > struct device_node *np; > - const u32 *sizep; > - const u64 *basep; > struct tpm_bios_log *log; > u32 size; > u64 base; > + int ret; > > log = &chip->log; > if (chip->dev.parent && chip->dev.parent->of_node) > @@ -35,30 +35,9 @@ int tpm_read_log_of(struct tpm_chip *chip) > if (of_property_read_bool(np, "powered-while-suspended")) > chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; > > - sizep = of_get_property(np, "linux,sml-size", NULL); > - basep = of_get_property(np, "linux,sml-base", NULL); > - if (sizep == NULL && basep == NULL) > - return -ENODEV; > - if (sizep == NULL || basep == NULL) > - return -EIO; > - > - /* > - * For both vtpm/tpm, firmware has log addr and log size in big > - * endian format. But in case of vtpm, there is a method called > - * sml-handover which is run during kernel init even before > - * device tree is setup. This sml-handover function takes care > - * of endianness and writes to sml-base and sml-size in little > - * endian format. For this reason, vtpm doesn't need conversion > - * but physical tpm needs the conversion. > - */ > - if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0 && > - of_property_match_string(np, "compatible", "IBM,vtpm20") < 0) { > - size = be32_to_cpup((__force __be32 *)sizep); > - base = be64_to_cpup((__force __be64 *)basep); > - } else { > - size = *sizep; > - base = *basep; > - } > + ret = of_tpm_get_sml_parameters(np, &base, &size); > + if (ret < 0) > + return ret; > > if (size == 0) { > dev_warn(&chip->dev, "%s: Event log area empty\n", __func__); > diff --git a/drivers/of/Makefile b/drivers/of/Makefile > index e0360a44306e..1c9feac450ad 100644 > --- a/drivers/of/Makefile > +++ b/drivers/of/Makefile > @@ -1,5 +1,5 @@ > # SPDX-License-Identifier: GPL-2.0 > -obj-y = base.o device.o platform.o property.o > +obj-y = base.o device.o platform.o property.o device_node.o > obj-$(CONFIG_OF_KOBJ) += kobj.o > obj-$(CONFIG_OF_DYNAMIC) += dynamic.o > obj-$(CONFIG_OF_FLATTREE) += fdt.o > diff --git a/drivers/of/device_node.c b/drivers/of/device_node.c > new file mode 100644 > index 000000000000..71a19bc1bac2 > --- /dev/null > +++ b/drivers/of/device_node.c > @@ -0,0 +1,27 @@ > +// SPDX-License-Identifier: GPL-2.0 > +#include <linux/export.h> > +#include <linux/of_device_node.h> > + > +int of_tpm_get_sml_parameters(struct device_node *np, u64 *base, u32 *size) > +{ > + const u32 *sizep; > + const u64 *basep; > + > + sizep = of_get_property(np, "linux,sml-size", NULL); > + basep = of_get_property(np, "linux,sml-base", NULL); > + if (sizep == NULL && basep == NULL) > + return -ENODEV; > + if (sizep == NULL || basep == NULL) > + return -EIO; > + > + if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0 && > + of_property_match_string(np, "compatible", "IBM,vtpm20") < 0) { > + *size = be32_to_cpup((__force __be32 *)sizep); > + *base = be64_to_cpup((__force __be64 *)basep); > + } else { > + *size = *sizep; > + *base = *basep; > + } > + return 0; > +} > +EXPORT_SYMBOL_GPL(of_tpm_get_sml_parameters); > diff --git a/include/linux/of_device_node.h b/include/linux/of_device_node.h > new file mode 100644 > index 000000000000..ae3faf023aab > --- /dev/null > +++ b/include/linux/of_device_node.h > @@ -0,0 +1,9 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +#ifndef _LINUX_OF_DEVICE_NODE_H > +#define _LINUX_OF_DEVICE_NODE_H > + > +#include <linux/of.h> > + > +int of_tpm_get_sml_parameters(struct device_node *np, u64 *base, u32 *size); > + > +#endif /* _LINUX_OF_DEVICE_NODE_H */ > -- > 2.35.1 > >
On Wed, Jun 29, 2022 at 10:16:37AM -0400, Stefan Berger wrote: > > > On 6/28/22 22:45, Jarkko Sakkinen wrote: > > On Tue, Jun 28, 2022 at 09:29:48AM -0400, Stefan Berger wrote: > > > > > > > > > On 6/27/22 18:43, Rob Herring wrote: > > > > On Thu, Jun 16, 2022 at 11:41:28AM -0400, Stefan Berger wrote: > > > > > Simplify tpm_read_log_of() by moving Openfirmware-specific code into > > > > > the Openfirmware driver to make the code reusable. Call the new > > > > > > > > There is no such 'Openfirmware driver'. > > > > > > > > > of_tpm_get_sml_parameters() function from the TPM Openfirmware driver. > > > > > > > > > > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> > > > > > Cc: Jarkko Sakkinen <jarkko@kernel.org> > > > > > Cc: Jason Gunthorpe <jgg@ziepe.ca> > > > > > Cc: Rob Herring <robh+dt@kernel.org> > > > > > Cc: Frank Rowand <frowand.list@gmail.com> > > > > > --- > > > > > drivers/char/tpm/eventlog/of.c | 31 +++++-------------------------- > > > > > drivers/of/Makefile | 2 +- > > > > > drivers/of/device_node.c | 27 +++++++++++++++++++++++++++ > > > > > > > > Humm, definitely the wrong direction. Generally, code for specific > > > > bindings does not go in drivers/of/. There used to be some, but we've > > > > moved it to the appropriate subsystems. kexec was an exception to not > > > > have 2 copies of the same code in arch/. > > > > > > The function I am moving here is called by the TPM subsystem and also now by > > > of/kexec.c. The latter is compiled under the following conditions: > > > > > > ifdef CONFIG_KEXEC_FILE > > > ifdef CONFIG_OF_FLATTREE > > > obj-y += kexec.o > > > endif > > > endif > > > > > > The code that current calls it is compiled under the following conditions: > > > > > > tpm-$(CONFIG_OF) += eventlog/of.o > > > > > > To make it available to both I could keep it in the TPM subsystem like this: > > > > > > obj-$(CONFIG_OF) = tpm_of.o > > > > > > > > > Jarrko, if you read this, any comment? > > > > > > > > > Stefan > > > > Why can't you convert of_tpm_get_sml_parameters() to inline function? > > I can do that and put it into include/linux/tpm.h. The only concern would > have been the size of the function. It is somewhat insignificant amount (dozens of bytes at most). BR, Jarkko