Some platforms may desire to pass the event log up to Linux in the
form of a reserved memory region. In particular, this is desirable
for embedded systems or baseboard management controllers (BMCs)
booting with U-Boot. IBM OpenBMC BMCs will be the first user.
Add support for the reserved memory in the TPM core to find the
region and map it.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
drivers/char/tpm/eventlog/of.c | 38 +++++++++++++++++++++++++++++++++-
1 file changed, 37 insertions(+), 1 deletion(-)
diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c
index 741ab2204b11..c815cadf00a4 100644
--- a/drivers/char/tpm/eventlog/of.c
+++ b/drivers/char/tpm/eventlog/of.c
@@ -12,12 +12,48 @@
#include <linux/device.h>
#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
#include <linux/tpm_eventlog.h>
#include "../tpm.h"
#include "common.h"
+static int tpm_read_log_memory_region(struct tpm_chip *chip)
+{
+ struct device_node *node;
+ struct resource res;
+ int rc;
+
+ node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0);
+ if (!node) {
+ dev_info(&chip->dev, "no phandle\n");
+ return -ENODEV;
+ }
+
+ rc = of_address_to_resource(node, 0, &res);
+ of_node_put(node);
+ if (rc) {
+ dev_info(&chip->dev, "no mem\n");
+ return rc;
+ }
+
+ chip->log.bios_event_log = devm_memremap(&chip->dev, res.start, resource_size(&res),
+ MEMREMAP_WB);
+ if (!chip->log.bios_event_log) {
+ dev_info(&chip->dev, "err memremap\n");
+ return -ENOMEM;
+ }
+
+ chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res);
+
+ return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 :
+ EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
+}
+
int tpm_read_log_of(struct tpm_chip *chip)
{
struct device_node *np;
@@ -39,7 +75,7 @@ int tpm_read_log_of(struct tpm_chip *chip)
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;
+ return tpm_read_log_memory_region(chip);
if (sizep == NULL || basep == NULL)
return -EIO;
--
2.31.1
On Thu, Jan 26, 2023 at 03:08:10PM -0600, Eddie James wrote:
> Some platforms may desire to pass the event log up to Linux in the
> form of a reserved memory region. In particular, this is desirable
> for embedded systems or baseboard management controllers (BMCs)
> booting with U-Boot. IBM OpenBMC BMCs will be the first user.
> Add support for the reserved memory in the TPM core to find the
> region and map it.
>
> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> ---
> drivers/char/tpm/eventlog/of.c | 38 +++++++++++++++++++++++++++++++++-
> 1 file changed, 37 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c
> index 741ab2204b11..c815cadf00a4 100644
> --- a/drivers/char/tpm/eventlog/of.c
> +++ b/drivers/char/tpm/eventlog/of.c
> @@ -12,12 +12,48 @@
>
> #include <linux/device.h>
> #include <linux/slab.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
> #include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_reserved_mem.h>
> #include <linux/tpm_eventlog.h>
>
> #include "../tpm.h"
> #include "common.h"
>
> +static int tpm_read_log_memory_region(struct tpm_chip *chip)
> +{
> + struct device_node *node;
> + struct resource res;
> + int rc;
> +
> + node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0);
> + if (!node) {
> + dev_info(&chip->dev, "no phandle\n");
> + return -ENODEV;
> + }
> +
> + rc = of_address_to_resource(node, 0, &res);
> + of_node_put(node);
> + if (rc) {
> + dev_info(&chip->dev, "no mem\n");
> + return rc;
> + }
> +
> + chip->log.bios_event_log = devm_memremap(&chip->dev, res.start, resource_size(&res),
> + MEMREMAP_WB);
> + if (!chip->log.bios_event_log) {
> + dev_info(&chip->dev, "err memremap\n");
> + return -ENOMEM;
> + }
> +
> + chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res);
> +
> + return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 :
> + EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
> +}
> +
> int tpm_read_log_of(struct tpm_chip *chip)
> {
> struct device_node *np;
> @@ -39,7 +75,7 @@ int tpm_read_log_of(struct tpm_chip *chip)
> 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;
> + return tpm_read_log_memory_region(chip);
> if (sizep == NULL || basep == NULL)
> return -EIO;
>
> --
> 2.31.1
>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
BR, Jarkko
On Thu, Jan 26, 2023 at 09:42:55PM +0000, Jarkko Sakkinen wrote:
> On Thu, Jan 26, 2023 at 03:08:10PM -0600, Eddie James wrote:
> > Some platforms may desire to pass the event log up to Linux in the
> > form of a reserved memory region. In particular, this is desirable
> > for embedded systems or baseboard management controllers (BMCs)
> > booting with U-Boot. IBM OpenBMC BMCs will be the first user.
> > Add support for the reserved memory in the TPM core to find the
> > region and map it.
> >
> > Signed-off-by: Eddie James <eajames@linux.ibm.com>
> > ---
> > drivers/char/tpm/eventlog/of.c | 38 +++++++++++++++++++++++++++++++++-
> > 1 file changed, 37 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c
> > index 741ab2204b11..c815cadf00a4 100644
> > --- a/drivers/char/tpm/eventlog/of.c
> > +++ b/drivers/char/tpm/eventlog/of.c
> > @@ -12,12 +12,48 @@
> >
> > #include <linux/device.h>
> > #include <linux/slab.h>
> > +#include <linux/io.h>
> > +#include <linux/ioport.h>
> > #include <linux/of.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_reserved_mem.h>
> > #include <linux/tpm_eventlog.h>
> >
> > #include "../tpm.h"
> > #include "common.h"
> >
> > +static int tpm_read_log_memory_region(struct tpm_chip *chip)
> > +{
> > + struct device_node *node;
> > + struct resource res;
> > + int rc;
> > +
> > + node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0);
> > + if (!node) {
> > + dev_info(&chip->dev, "no phandle\n");
> > + return -ENODEV;
> > + }
> > +
> > + rc = of_address_to_resource(node, 0, &res);
> > + of_node_put(node);
> > + if (rc) {
> > + dev_info(&chip->dev, "no mem\n");
> > + return rc;
> > + }
> > +
> > + chip->log.bios_event_log = devm_memremap(&chip->dev, res.start, resource_size(&res),
> > + MEMREMAP_WB);
> > + if (!chip->log.bios_event_log) {
> > + dev_info(&chip->dev, "err memremap\n");
> > + return -ENOMEM;
> > + }
> > +
> > + chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res);
> > +
> > + return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 :
> > + EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
> > +}
> > +
> > int tpm_read_log_of(struct tpm_chip *chip)
> > {
> > struct device_node *np;
> > @@ -39,7 +75,7 @@ int tpm_read_log_of(struct tpm_chip *chip)
> > 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;
> > + return tpm_read_log_memory_region(chip);
> > if (sizep == NULL || basep == NULL)
> > return -EIO;
> >
> > --
> > 2.31.1
> >
>
> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
I applied the patches.
BR, Jarkko
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