| Message ID | 1576221267-5948-6-git-send-email-sughosh.ganu@linaro.org |
|---|---|
| State | Superseded, archived |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | Add a random number generator uclass | expand |
Hi, > From: U-Boot <u-boot-bounces@lists.denx.de> On Behalf Of Sughosh Ganu > Sent: vendredi 13 décembre 2019 08:14 > > Add a sandbox driver for random number generation. Mostly aimed at providing a > unit test for rng uclass. > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > Reviewed-by: Patrice Chotard <patrice.chotard@st.com> > --- > arch/sandbox/dts/test.dts | 4 ++++ > drivers/rng/Kconfig | 7 +++++++ > drivers/rng/Makefile | 1 + > drivers/rng/sandbox_rng.c | 36 ++++++++++++++++++++++++++++++++++++ > 4 files changed, 48 insertions(+) > create mode 100644 drivers/rng/sandbox_rng.c > > diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts index > fdb08f2..2c85540 100644 > --- a/arch/sandbox/dts/test.dts > +++ b/arch/sandbox/dts/test.dts > @@ -599,6 +599,10 @@ > reset-names = "other", "test"; > }; > > + rng@0 { > + compatible = "sandbox,sandbox-rng"; > + }; > + > rproc_1: rproc@1 { > compatible = "sandbox,test-processor"; > remoteproc-name = "remoteproc-test-dev1"; diff --git > a/drivers/rng/Kconfig b/drivers/rng/Kconfig index 5fc11db..3a1d3f0 100644 > --- a/drivers/rng/Kconfig > +++ b/drivers/rng/Kconfig > @@ -6,6 +6,13 @@ config DM_RNG > This interface is used to initialise the rng device and to > read the random seed from the device. > > +config RNG_SANDBOX > + bool "Sandbox random number generator" > + depends on SANDBOX && DM_RNG > + help > + Enable random number generator for sandbox. This is an > + emulation of a rng device. > + > config RNG_STM32MP1 > bool "Enable random number generator for STM32MP1" > depends on ARCH_STM32MP && DM_RNG diff --git a/drivers/rng/Makefile > b/drivers/rng/Makefile index 699beb3..3517005 100644 > --- a/drivers/rng/Makefile > +++ b/drivers/rng/Makefile > @@ -4,4 +4,5 @@ > # > > obj-$(CONFIG_DM_RNG) += rng-uclass.o > +obj-$(CONFIG_RNG_SANDBOX) += sandbox_rng.o > obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o diff --git > a/drivers/rng/sandbox_rng.c b/drivers/rng/sandbox_rng.c new file mode 100644 > index 0000000..c5be552 > --- /dev/null > +++ b/drivers/rng/sandbox_rng.c > @@ -0,0 +1,36 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2019, Linaro Limited > + */ > + > +#include <common.h> > +#include <dm.h> > +#include <rng.h> > + > +static unsigned long random = 0xdeadbeef; > + > +static int sandbox_rng_read(struct udevice *dev, void *data, size_t > +len) { Add protection on length I think: If (len != sizeof(random)) retrun - EINVAL; or treat the case len > 4 with loop ? > + random ^= ~0UL; > + *(unsigned long *)data = random; > + > + return sizeof(random); Read is OK, so I think the correct return value is 0: return 0; NB: result (int) can be not enough to return the value read (size_t) PS: it not really a random generator here but simple sequence 0xdeadbeef -> 0x21524110 -> 0xdeadbeef It is enough for unitary test, but is is enough for sandbox ? we could reused PRNG code from lib/rand.c ? > +} > + > +static const struct dm_rng_ops sandbox_rng_ops = { > + .read = sandbox_rng_read, > +}; > + > +static const struct udevice_id sandbox_rng_match[] = { > + { > + .compatible = "sandbox,sandbox-rng", > + }, > + {}, > +}; > + > +U_BOOT_DRIVER(sandbox_rng) = { > + .name = "sandbox-rng", > + .id = UCLASS_RNG, > + .of_match = sandbox_rng_match, > + .ops = &sandbox_rng_ops, > +}; > -- > 2.7.4
hi Patrick, On Mon, 16 Dec 2019 at 18:00, Patrick DELAUNAY <patrick.delaunay@st.com> wrote: > Hi, > > > From: U-Boot <u-boot-bounces@lists.denx.de> On Behalf Of Sughosh Ganu > > Sent: vendredi 13 décembre 2019 08:14 > > > > Add a sandbox driver for random number generation. Mostly aimed at > providing a > > unit test for rng uclass. > > > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > > Reviewed-by: Patrice Chotard <patrice.chotard@st.com> > > --- > > arch/sandbox/dts/test.dts | 4 ++++ > > drivers/rng/Kconfig | 7 +++++++ > > drivers/rng/Makefile | 1 + > > drivers/rng/sandbox_rng.c | 36 ++++++++++++++++++++++++++++++++++++ > > 4 files changed, 48 insertions(+) > > create mode 100644 drivers/rng/sandbox_rng.c > <snip> > > > a/drivers/rng/sandbox_rng.c b/drivers/rng/sandbox_rng.c new file mode > 100644 > > index 0000000..c5be552 > > --- /dev/null > > +++ b/drivers/rng/sandbox_rng.c > > @@ -0,0 +1,36 @@ > > +// SPDX-License-Identifier: GPL-2.0-or-later > > +/* > > + * Copyright (c) 2019, Linaro Limited > > + */ > > + > > +#include <common.h> > > +#include <dm.h> > > +#include <rng.h> > > + > > +static unsigned long random = 0xdeadbeef; > > + > > +static int sandbox_rng_read(struct udevice *dev, void *data, size_t > > +len) { > > Add protection on length I think: > If (len != sizeof(random)) > retrun - EINVAL; > Ok. Will add this check. > > or treat the case len > 4 with loop ? > > > + random ^= ~0UL; > > + *(unsigned long *)data = random; > > + > > + return sizeof(random); > > Read is OK, so I think the correct return value is 0: > Ok. Will change. > > return 0; > > NB: result (int) can be not enough to return the value read (size_t) > > PS: it not really a random generator here but simple sequence > 0xdeadbeef -> 0x21524110 -> 0xdeadbeef > > It is enough for unitary test, but is is enough for sandbox ? > we could reused PRNG code from lib/rand.c ? > I actually wrote this solely from the point of view of adding a unit test for the rng uclass. For which i think the simple sequence above should suffice. Do you have a strong opinion on this. If so, i can change the logic. -sughosh > >
diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts index fdb08f2..2c85540 100644 --- a/arch/sandbox/dts/test.dts +++ b/arch/sandbox/dts/test.dts @@ -599,6 +599,10 @@ reset-names = "other", "test"; }; + rng@0 { + compatible = "sandbox,sandbox-rng"; + }; + rproc_1: rproc@1 { compatible = "sandbox,test-processor"; remoteproc-name = "remoteproc-test-dev1"; diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig index 5fc11db..3a1d3f0 100644 --- a/drivers/rng/Kconfig +++ b/drivers/rng/Kconfig @@ -6,6 +6,13 @@ config DM_RNG This interface is used to initialise the rng device and to read the random seed from the device. +config RNG_SANDBOX + bool "Sandbox random number generator" + depends on SANDBOX && DM_RNG + help + Enable random number generator for sandbox. This is an + emulation of a rng device. + config RNG_STM32MP1 bool "Enable random number generator for STM32MP1" depends on ARCH_STM32MP && DM_RNG diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile index 699beb3..3517005 100644 --- a/drivers/rng/Makefile +++ b/drivers/rng/Makefile @@ -4,4 +4,5 @@ # obj-$(CONFIG_DM_RNG) += rng-uclass.o +obj-$(CONFIG_RNG_SANDBOX) += sandbox_rng.o obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o diff --git a/drivers/rng/sandbox_rng.c b/drivers/rng/sandbox_rng.c new file mode 100644 index 0000000..c5be552 --- /dev/null +++ b/drivers/rng/sandbox_rng.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2019, Linaro Limited + */ + +#include <common.h> +#include <dm.h> +#include <rng.h> + +static unsigned long random = 0xdeadbeef; + +static int sandbox_rng_read(struct udevice *dev, void *data, size_t len) +{ + random ^= ~0UL; + *(unsigned long *)data = random; + + return sizeof(random); +} + +static const struct dm_rng_ops sandbox_rng_ops = { + .read = sandbox_rng_read, +}; + +static const struct udevice_id sandbox_rng_match[] = { + { + .compatible = "sandbox,sandbox-rng", + }, + {}, +}; + +U_BOOT_DRIVER(sandbox_rng) = { + .name = "sandbox-rng", + .id = UCLASS_RNG, + .of_match = sandbox_rng_match, + .ops = &sandbox_rng_ops, +};