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@xxxxxxxxxxxxx>
> Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> Cc: Jason Gunthorpe <jgg@xxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: Frank Rowand <frowand.list@xxxxxxxxx>
> ---
> 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
>
>
