| Message ID | 20220224180552.26901-9-sughosh.ganu@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tpm: rng: Move TPM RNG functionality to driver model | expand |
On 2/24/22 19:05, Sughosh Ganu wrote: > The TPM device comes with the random number generator(RNG) > functionality which is built into the TPM device. Add logic to add the > RNG child device in the TPM uclass post probe callback. > > The RNG device can then be used to pass a set of random bytes to the > linux kernel, need for address space randomisation through the > EFI_RNG_PROTOCOL interface. > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > --- > drivers/tpm/tpm-uclass.c | 58 +++++++++++++++++++++++++++++++++++++--- > 1 file changed, 54 insertions(+), 4 deletions(-) > > diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c > index 8619da89d8..383cc7bc48 100644 > --- a/drivers/tpm/tpm-uclass.c > +++ b/drivers/tpm/tpm-uclass.c > @@ -16,6 +16,11 @@ > #include <tpm-v2.h> > #include "tpm_internal.h" > > +#include <dm/lists.h> > + > +#define TPM_RNG1_DRV_NAME "tpm1-rng" > +#define TPM_RNG2_DRV_NAME "tpm2-rng" > + > bool is_tpm1(struct udevice *dev) > { > return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1; > @@ -147,12 +152,57 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, > return 0; > } > > +#if IS_ENABLED(CONFIG_TPM) This is is superfluous. This file is only compiled if CONFIG_$(SPL_TPL_)TPM = y. Best regards Heinrich > +static int tpm_uclass_post_probe(struct udevice *dev) > +{ > + int ret; > + const char *drv = is_tpm1(dev) ? TPM_RNG1_DRV_NAME : TPM_RNG2_DRV_NAME; > + struct udevice *child; > + > + ret = device_bind_driver(dev, drv, "tpm-rng0", &child); > + if (ret == -ENOENT) { > + log_err("No driver configured for tpm-rng device\n"); > + return 0; > + } > + > + if (ret) { > + log_err("Unable to bind rng driver with the tpm-rng device\n"); > + return ret; > + } > + > + return 0; > +} > + > +static int tpm_uclass_child_pre_probe(struct udevice *dev) > +{ > + int ret; > + > + ret = tpm_open(dev->parent); > + if (ret == -EBUSY) { > + log_info("TPM device already opened\n"); > + } else if (ret) { > + log_err("Unable to open TPM device\n"); > + return ret; > + } > + > + ret = tpm_startup(dev->parent, TPM_ST_CLEAR); > + if (ret) > + log_err("Unable to start TPM device\n"); > + > + return ret; > +} > +#endif /* CONFIG_TPM */ > + > UCLASS_DRIVER(tpm) = { > - .id = UCLASS_TPM, > - .name = "tpm", > - .flags = DM_UC_FLAG_SEQ_ALIAS, > + .id = UCLASS_TPM, > + .name = "tpm", > + .flags = DM_UC_FLAG_SEQ_ALIAS, > #if CONFIG_IS_ENABLED(OF_REAL) > - .post_bind = dm_scan_fdt_dev, > + .post_bind = dm_scan_fdt_dev, > +#endif > +#if IS_ENABLED(CONFIG_TPM) > + .post_probe = tpm_uclass_post_probe, > + .child_pre_probe = tpm_uclass_child_pre_probe, > #endif > .per_device_auto = sizeof(struct tpm_chip_priv), > };
On Fri, 25 Feb 2022 at 00:21, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: > > On 2/24/22 19:05, Sughosh Ganu wrote: > > The TPM device comes with the random number generator(RNG) > > functionality which is built into the TPM device. Add logic to add the > > RNG child device in the TPM uclass post probe callback. > > > > The RNG device can then be used to pass a set of random bytes to the > > linux kernel, need for address space randomisation through the > > EFI_RNG_PROTOCOL interface. > > > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > > --- > > drivers/tpm/tpm-uclass.c | 58 +++++++++++++++++++++++++++++++++++++--- > > 1 file changed, 54 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c > > index 8619da89d8..383cc7bc48 100644 > > --- a/drivers/tpm/tpm-uclass.c > > +++ b/drivers/tpm/tpm-uclass.c > > @@ -16,6 +16,11 @@ > > #include <tpm-v2.h> > > #include "tpm_internal.h" > > > > +#include <dm/lists.h> > > + > > +#define TPM_RNG1_DRV_NAME "tpm1-rng" > > +#define TPM_RNG2_DRV_NAME "tpm2-rng" > > + > > bool is_tpm1(struct udevice *dev) > > { > > return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1; > > @@ -147,12 +152,57 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, > > return 0; > > } > > > > +#if IS_ENABLED(CONFIG_TPM) > > This is is superfluous. > This file is only compiled if CONFIG_$(SPL_TPL_)TPM = y. Yes, but I want the RNG child device addition to be done only in case of u-boot proper, not for SPL and TPM. We do not have RNG support for the SPL/TPM boot stages. So unless someone needs to enable RNG support for SPL/TPL stages, which I doubt, this code should run only in u-boot proper. Thanks. -sughosh > > Best regards > > Heinrich > > > +static int tpm_uclass_post_probe(struct udevice *dev) > > +{ > > + int ret; > > + const char *drv = is_tpm1(dev) ? TPM_RNG1_DRV_NAME : TPM_RNG2_DRV_NAME; > > + struct udevice *child; > > + > > + ret = device_bind_driver(dev, drv, "tpm-rng0", &child); > > + if (ret == -ENOENT) { > > + log_err("No driver configured for tpm-rng device\n"); > > + return 0; > > + } > > + > > + if (ret) { > > + log_err("Unable to bind rng driver with the tpm-rng device\n"); > > + return ret; > > + } > > + > > + return 0; > > +} > > + > > +static int tpm_uclass_child_pre_probe(struct udevice *dev) > > +{ > > + int ret; > > + > > + ret = tpm_open(dev->parent); > > + if (ret == -EBUSY) { > > + log_info("TPM device already opened\n"); > > + } else if (ret) { > > + log_err("Unable to open TPM device\n"); > > + return ret; > > + } > > + > > + ret = tpm_startup(dev->parent, TPM_ST_CLEAR); > > + if (ret) > > + log_err("Unable to start TPM device\n"); > > + > > + return ret; > > +} > > +#endif /* CONFIG_TPM */ > > + > > UCLASS_DRIVER(tpm) = { > > - .id = UCLASS_TPM, > > - .name = "tpm", > > - .flags = DM_UC_FLAG_SEQ_ALIAS, > > + .id = UCLASS_TPM, > > + .name = "tpm", > > + .flags = DM_UC_FLAG_SEQ_ALIAS, > > #if CONFIG_IS_ENABLED(OF_REAL) > > - .post_bind = dm_scan_fdt_dev, > > + .post_bind = dm_scan_fdt_dev, > > +#endif > > +#if IS_ENABLED(CONFIG_TPM) > > + .post_probe = tpm_uclass_post_probe, > > + .child_pre_probe = tpm_uclass_child_pre_probe, > > #endif > > .per_device_auto = sizeof(struct tpm_chip_priv), > > }; >
On 2/25/22 06:45, Sughosh Ganu wrote: > On Fri, 25 Feb 2022 at 00:21, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: >> >> On 2/24/22 19:05, Sughosh Ganu wrote: >>> The TPM device comes with the random number generator(RNG) >>> functionality which is built into the TPM device. Add logic to add the >>> RNG child device in the TPM uclass post probe callback. >>> >>> The RNG device can then be used to pass a set of random bytes to the >>> linux kernel, need for address space randomisation through the >>> EFI_RNG_PROTOCOL interface. >>> >>> Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> >>> --- >>> drivers/tpm/tpm-uclass.c | 58 +++++++++++++++++++++++++++++++++++++--- >>> 1 file changed, 54 insertions(+), 4 deletions(-) >>> >>> diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c >>> index 8619da89d8..383cc7bc48 100644 >>> --- a/drivers/tpm/tpm-uclass.c >>> +++ b/drivers/tpm/tpm-uclass.c >>> @@ -16,6 +16,11 @@ >>> #include <tpm-v2.h> >>> #include "tpm_internal.h" >>> >>> +#include <dm/lists.h> >>> + >>> +#define TPM_RNG1_DRV_NAME "tpm1-rng" >>> +#define TPM_RNG2_DRV_NAME "tpm2-rng" >>> + >>> bool is_tpm1(struct udevice *dev) >>> { >>> return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1; >>> @@ -147,12 +152,57 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, >>> return 0; >>> } >>> >>> +#if IS_ENABLED(CONFIG_TPM) >> >> This is is superfluous. >> This file is only compiled if CONFIG_$(SPL_TPL_)TPM = y. > > Yes, but I want the RNG child device addition to be done only in case > of u-boot proper, not for SPL and TPM. We do not have RNG support for > the SPL/TPM boot stages. So unless someone needs to enable RNG support > for SPL/TPL stages, which I doubt, this code should run only in u-boot > proper. Thanks. The tpm-uclass.c is never compiled in SPL or TPL. Have a look at drivers/tpm/Kconfig. There is no CONFIG_SPL_TPM or CONFIG_TPL_TPM symbol. Best regards Heinrich > > -sughosh > >> >> Best regards >> >> Heinrich >> >>> +static int tpm_uclass_post_probe(struct udevice *dev) >>> +{ >>> + int ret; >>> + const char *drv = is_tpm1(dev) ? TPM_RNG1_DRV_NAME : TPM_RNG2_DRV_NAME; >>> + struct udevice *child; >>> + >>> + ret = device_bind_driver(dev, drv, "tpm-rng0", &child); >>> + if (ret == -ENOENT) { >>> + log_err("No driver configured for tpm-rng device\n"); >>> + return 0; >>> + } >>> + >>> + if (ret) { >>> + log_err("Unable to bind rng driver with the tpm-rng device\n"); >>> + return ret; >>> + } >>> + >>> + return 0; >>> +} >>> + >>> +static int tpm_uclass_child_pre_probe(struct udevice *dev) >>> +{ >>> + int ret; >>> + >>> + ret = tpm_open(dev->parent); >>> + if (ret == -EBUSY) { >>> + log_info("TPM device already opened\n"); >>> + } else if (ret) { >>> + log_err("Unable to open TPM device\n"); >>> + return ret; >>> + } >>> + >>> + ret = tpm_startup(dev->parent, TPM_ST_CLEAR); >>> + if (ret) >>> + log_err("Unable to start TPM device\n"); >>> + >>> + return ret; >>> +} >>> +#endif /* CONFIG_TPM */ >>> + >>> UCLASS_DRIVER(tpm) = { >>> - .id = UCLASS_TPM, >>> - .name = "tpm", >>> - .flags = DM_UC_FLAG_SEQ_ALIAS, >>> + .id = UCLASS_TPM, >>> + .name = "tpm", >>> + .flags = DM_UC_FLAG_SEQ_ALIAS, >>> #if CONFIG_IS_ENABLED(OF_REAL) >>> - .post_bind = dm_scan_fdt_dev, >>> + .post_bind = dm_scan_fdt_dev, >>> +#endif >>> +#if IS_ENABLED(CONFIG_TPM) >>> + .post_probe = tpm_uclass_post_probe, >>> + .child_pre_probe = tpm_uclass_child_pre_probe, >>> #endif >>> .per_device_auto = sizeof(struct tpm_chip_priv), >>> }; >>
hello Heinrich, On Fri, 25 Feb 2022 at 12:00, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: > > On 2/25/22 06:45, Sughosh Ganu wrote: > > On Fri, 25 Feb 2022 at 00:21, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: > >> > >> On 2/24/22 19:05, Sughosh Ganu wrote: > >>> The TPM device comes with the random number generator(RNG) > >>> functionality which is built into the TPM device. Add logic to add the > >>> RNG child device in the TPM uclass post probe callback. > >>> > >>> The RNG device can then be used to pass a set of random bytes to the > >>> linux kernel, need for address space randomisation through the > >>> EFI_RNG_PROTOCOL interface. > >>> > >>> Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > >>> --- > >>> drivers/tpm/tpm-uclass.c | 58 +++++++++++++++++++++++++++++++++++++--- > >>> 1 file changed, 54 insertions(+), 4 deletions(-) > >>> > >>> diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c > >>> index 8619da89d8..383cc7bc48 100644 > >>> --- a/drivers/tpm/tpm-uclass.c > >>> +++ b/drivers/tpm/tpm-uclass.c > >>> @@ -16,6 +16,11 @@ > >>> #include <tpm-v2.h> > >>> #include "tpm_internal.h" > >>> > >>> +#include <dm/lists.h> > >>> + > >>> +#define TPM_RNG1_DRV_NAME "tpm1-rng" > >>> +#define TPM_RNG2_DRV_NAME "tpm2-rng" > >>> + > >>> bool is_tpm1(struct udevice *dev) > >>> { > >>> return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1; > >>> @@ -147,12 +152,57 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, > >>> return 0; > >>> } > >>> > >>> +#if IS_ENABLED(CONFIG_TPM) > >> > >> This is is superfluous. > >> This file is only compiled if CONFIG_$(SPL_TPL_)TPM = y. > > > > Yes, but I want the RNG child device addition to be done only in case > > of u-boot proper, not for SPL and TPM. We do not have RNG support for > > the SPL/TPM boot stages. So unless someone needs to enable RNG support > > for SPL/TPL stages, which I doubt, this code should run only in u-boot > > proper. Thanks. > > The tpm-uclass.c is never compiled in SPL or TPL. Have a look at > drivers/tpm/Kconfig. There is no CONFIG_SPL_TPM or CONFIG_TPL_TPM symbol. The {S,T}PL_TPM symbol is actually defined under lib/Kconfig. Currently it is not getting defined in any platform's defconfig, but one can add it and build the tpm-uclass driver for the SPL/TPL stage as well. I added the SPL_TPM config to the chromebook_coral and it indeed builds the tpm-uclass driver. Thanks. -sughosh > > Best regards > > Heinrich > > > > > -sughosh > > > >> > >> Best regards > >> > >> Heinrich > >> > >>> +static int tpm_uclass_post_probe(struct udevice *dev) > >>> +{ > >>> + int ret; > >>> + const char *drv = is_tpm1(dev) ? TPM_RNG1_DRV_NAME : TPM_RNG2_DRV_NAME; > >>> + struct udevice *child; > >>> + > >>> + ret = device_bind_driver(dev, drv, "tpm-rng0", &child); > >>> + if (ret == -ENOENT) { > >>> + log_err("No driver configured for tpm-rng device\n"); > >>> + return 0; > >>> + } > >>> + > >>> + if (ret) { > >>> + log_err("Unable to bind rng driver with the tpm-rng device\n"); > >>> + return ret; > >>> + } > >>> + > >>> + return 0; > >>> +} > >>> + > >>> +static int tpm_uclass_child_pre_probe(struct udevice *dev) > >>> +{ > >>> + int ret; > >>> + > >>> + ret = tpm_open(dev->parent); > >>> + if (ret == -EBUSY) { > >>> + log_info("TPM device already opened\n"); > >>> + } else if (ret) { > >>> + log_err("Unable to open TPM device\n"); > >>> + return ret; > >>> + } > >>> + > >>> + ret = tpm_startup(dev->parent, TPM_ST_CLEAR); > >>> + if (ret) > >>> + log_err("Unable to start TPM device\n"); > >>> + > >>> + return ret; > >>> +} > >>> +#endif /* CONFIG_TPM */ > >>> + > >>> UCLASS_DRIVER(tpm) = { > >>> - .id = UCLASS_TPM, > >>> - .name = "tpm", > >>> - .flags = DM_UC_FLAG_SEQ_ALIAS, > >>> + .id = UCLASS_TPM, > >>> + .name = "tpm", > >>> + .flags = DM_UC_FLAG_SEQ_ALIAS, > >>> #if CONFIG_IS_ENABLED(OF_REAL) > >>> - .post_bind = dm_scan_fdt_dev, > >>> + .post_bind = dm_scan_fdt_dev, > >>> +#endif > >>> +#if IS_ENABLED(CONFIG_TPM) > >>> + .post_probe = tpm_uclass_post_probe, > >>> + .child_pre_probe = tpm_uclass_child_pre_probe, > >>> #endif > >>> .per_device_auto = sizeof(struct tpm_chip_priv), > >>> }; > >> >
diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c index 8619da89d8..383cc7bc48 100644 --- a/drivers/tpm/tpm-uclass.c +++ b/drivers/tpm/tpm-uclass.c @@ -16,6 +16,11 @@ #include <tpm-v2.h> #include "tpm_internal.h" +#include <dm/lists.h> + +#define TPM_RNG1_DRV_NAME "tpm1-rng" +#define TPM_RNG2_DRV_NAME "tpm2-rng" + bool is_tpm1(struct udevice *dev) { return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1; @@ -147,12 +152,57 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, return 0; } +#if IS_ENABLED(CONFIG_TPM) +static int tpm_uclass_post_probe(struct udevice *dev) +{ + int ret; + const char *drv = is_tpm1(dev) ? TPM_RNG1_DRV_NAME : TPM_RNG2_DRV_NAME; + struct udevice *child; + + ret = device_bind_driver(dev, drv, "tpm-rng0", &child); + if (ret == -ENOENT) { + log_err("No driver configured for tpm-rng device\n"); + return 0; + } + + if (ret) { + log_err("Unable to bind rng driver with the tpm-rng device\n"); + return ret; + } + + return 0; +} + +static int tpm_uclass_child_pre_probe(struct udevice *dev) +{ + int ret; + + ret = tpm_open(dev->parent); + if (ret == -EBUSY) { + log_info("TPM device already opened\n"); + } else if (ret) { + log_err("Unable to open TPM device\n"); + return ret; + } + + ret = tpm_startup(dev->parent, TPM_ST_CLEAR); + if (ret) + log_err("Unable to start TPM device\n"); + + return ret; +} +#endif /* CONFIG_TPM */ + UCLASS_DRIVER(tpm) = { - .id = UCLASS_TPM, - .name = "tpm", - .flags = DM_UC_FLAG_SEQ_ALIAS, + .id = UCLASS_TPM, + .name = "tpm", + .flags = DM_UC_FLAG_SEQ_ALIAS, #if CONFIG_IS_ENABLED(OF_REAL) - .post_bind = dm_scan_fdt_dev, + .post_bind = dm_scan_fdt_dev, +#endif +#if IS_ENABLED(CONFIG_TPM) + .post_probe = tpm_uclass_post_probe, + .child_pre_probe = tpm_uclass_child_pre_probe, #endif .per_device_auto = sizeof(struct tpm_chip_priv), };
The TPM device comes with the random number generator(RNG) functionality which is built into the TPM device. Add logic to add the RNG child device in the TPM uclass post probe callback. The RNG device can then be used to pass a set of random bytes to the linux kernel, need for address space randomisation through the EFI_RNG_PROTOCOL interface. Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> --- drivers/tpm/tpm-uclass.c | 58 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 54 insertions(+), 4 deletions(-)