[PATCH] Added Getentropy() support to beagle BSP
Sebastian Huber
sebastian.huber at embedded-brains.de
Tue Mar 13 06:31:28 UTC 2018
On 12/03/18 20:02, Udit agarwal wrote:
> So, It looks like here's the final patch, do let me know if its ready
> to be pushed. Also, it would be really helpful if someone else also
> tests this patch before pushing(Although i have done that once).
>
> Thanks,
> Udit agarwal
>
>
> From 454a8ff3e0ea3393818859874705a54b098c6081 Mon Sep 17 00:00:00 2001
> From: Udit agarwal <dev.madaari at gmail.com <mailto:dev.madaari at gmail.com>>
> Date: Tue, 13 Mar 2018 00:20:28 +0530
> Subject: [PATCH] Added Getentropy() support to beagle BSP
>
> ---
> bsps/arm/include/libcpu/am335x.h | 37 ++++++-
> c/src/lib/libbsp/arm/beagle/Makefile.am | 4 +-
> .../libbsp/arm/beagle/getentropy/bbb_getentropy.c | 116
> +++++++++++++++++++++
> 3 files changed, 155 insertions(+), 2 deletions(-)
> create mode 100644
> c/src/lib/libbsp/arm/beagle/getentropy/bbb_getentropy.c
>
> diff --git a/bsps/arm/include/libcpu/am335x.h
> b/bsps/arm/include/libcpu/am335x.h
> index 367e97c..cedd637 100644
> --- a/bsps/arm/include/libcpu/am335x.h
> +++ b/bsps/arm/include/libcpu/am335x.h
> @@ -14,11 +14,17 @@
> * Modified by Ben Gras <beng at shrike-systems.com
> <mailto:beng at shrike-systems.com>> to add lots
> * of beagleboard/beaglebone definitions, delete lpc32xx specific
> * ones, and merge with some other header files.
> + *
> + * Modified by Udit agarwal <dev.madaari at gmail.com
> <mailto:dev.madaari at gmail.com>> to add random
> + * number generating module definitions and TRNG register structure.
> */
>
> #if !defined(_AM335X_H_)
> #define _AM335X_H_
>
> +/* For TRNG register definition */
> +#include <stdint.h>
> +
> /* Interrupt controller memory map */
> #define OMAP3_DM37XX_INTR_BASE 0x48200000 /* INTCPS physical address */
>
> @@ -701,4 +707,33 @@
> #define AM335X_CM_PER_OCPWP_L3_CLKSTCTRL_CLKACTIVITY_OCPWP_L4_GCLK
> (0x00000020u)
> #define AM335X_I2C_INT_STOP_CONDITION AM335X_I2C_IRQSTATUS_BF
>
> -#endif
> +/* TRNG Register */
> +
> +/* RNG base address */
> +#define RNG_BASE 0x48310000
> +/* RNG clock control */
> +#define CM_PER_RNG_CLKCTRL (AM335X_CM_PER_ADDR | (9 << 4))
> +/* rng module clock status bits */
> +#define AM335X_CLK_RNG_BIT_MASK (0x30000)
> +/* Offset from RNG base for output ready flag */
> +#define RNG_STATUS_RDY (1u << 0)
> +/* Offset from RNG base for FRO related error */
> +#define RNG_STATUS_ERR (1u << 1)
> +/* Offset from RNG base for clock status */
> +#define RNG_STATUS_CLK (1u << 31)
> +/* enable module */
> +#define AM335X_RNG_ENABLE (1 << 10)
> +
> +/* TRNG register structure */
> +struct bbb_trng_register
> +{
> + uint64_t output; /* 00 */
> + uint32_t status; /* 08 */
> + uint32_t irq_en; /* 0c */
> + uint32_t status_clr; /* 10 */
> + uint32_t control; /* 14 */
> + uint32_t config; /* 18 */
> +};
> +typedef struct bbb_trng_register bbb_trng_register;
The bbb (Beagle Bone Black) is a particular board and the AM335X is a
SoC family. This should be something like this
typedef struct {
...
} am335x_trng;
> +
> +#endif
> \ No newline at end of file
Git thinks that files should have a newline at the end of the file.
> diff --git a/c/src/lib/libbsp/arm/beagle/Makefile.am
> b/c/src/lib/libbsp/arm/beagle/Makefile.am
> index 8251660..5d5ade3 100644
> --- a/c/src/lib/libbsp/arm/beagle/Makefile.am
> +++ b/c/src/lib/libbsp/arm/beagle/Makefile.am
> @@ -40,7 +40,6 @@ libbsp_a_LIBADD =
>
> # Shared
> libbsp_a_SOURCES += ../../shared/bootcard.c
> -libbsp_a_SOURCES += ../../shared/getentropy-cpucounter.c
> libbsp_a_SOURCES += ../../shared/src/bsp-fdt.c
> libbsp_a_SOURCES += ../../shared/bspclean.c
> libbsp_a_SOURCES += ../../shared/bspgetworkarea.c
> @@ -88,6 +87,9 @@ libbsp_a_SOURCES += gpio/bbb-gpio.c
> #pwm
> libbsp_a_SOURCES += pwm/pwm.c
>
> +#getentropy
> +libbsp_a_SOURCES += getentropy/bbb_getentropy.c
> +
With the new BSP source structure
https://devel.rtems.org/ticket/3285
this new file could be also placed at
bsps/arm/beagle/dev/getentropy.c
> [...]
> +int getentropy(void *ptr, size_t n)
> +{
> + volatile bbb_trng_register *rng = (bbb_trng_register*) RNG_BASE;
> + am335x_rng_enable(rng);
> + while (n > 0)
> + {
> + uint64_t random;
> + size_t copy;
> +
> + /* wait untill RNG becomes ready with next set of random data */
> + while( ( rng->status & RNG_STATUS_RDY ) == 0 )
> + {
> + /* wait */
> + }
What happens if you call this function in parallel on different processors?
> +
> + random = trng_getranddata(rng);
> +
> + /* Checking for error by masking all bits other then error bit in
> + status register */
> + if( ((rng->status & RNG_STATUS_ERR)>>1) == 1)
> + {
> + /* clear the status flag after reading to generate new
> random
> + value */
> + rng->status_clr = RNG_STATUS_RDY;
> + copy = sizeof(random);
> + if ( n < copy )
> + {
> + copy = n;
> + }
> + memcpy(ptr, &random, copy);
> + n -= copy;
> + ptr = (char*)ptr + copy;
> + }
> + }
> +
> + return 0;
> +}
> +
> +RTEMS_SYSINIT_ITEM(
> + am335x_rng_clock_enable,
> + RTEMS_SYSINIT_DEVICE_DRIVERS,
> + RTEMS_SYSINIT_ORDER_LAST
> +);
> \ No newline at end of file
> --
> 1.9.1
>
>
>
>
> _______________________________________________
> devel mailing list
> devel at rtems.org
> http://lists.rtems.org/mailman/listinfo/devel
--
Sebastian Huber, embedded brains GmbH
Address : Dornierstr. 4, D-82178 Puchheim, Germany
Phone : +49 89 189 47 41-16
Fax : +49 89 189 47 41-09
E-Mail : sebastian.huber at embedded-brains.de
PGP : Public key available on request.
Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
More information about the devel
mailing list