On Wed, 4 Dec 2019 at 04:54, Sughosh Ganu sughosh.ganu@linaro.org wrote:

Add a uclass for reading a random number seed from a random number generator device.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

drivers/Kconfig | 2 ++ drivers/Makefile | 1 + drivers/rng/Kconfig | 7 +++++++ drivers/rng/Makefile | 6 ++++++ drivers/rng/rng-uclass.c | 23 +++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/rng.h | 25 +++++++++++++++++++++++++ 7 files changed, 65 insertions(+) create mode 100644 drivers/rng/Kconfig create mode 100644 drivers/rng/Makefile create mode 100644 drivers/rng/rng-uclass.c create mode 100644 include/rng.h

Reviewed-by: Simon Glass sjg@chromium.org

nits below

diff --git a/drivers/Kconfig b/drivers/Kconfig index 9d99ce0..e34a227 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -90,6 +90,8 @@ source "drivers/remoteproc/Kconfig"

source "drivers/reset/Kconfig"

+source "drivers/rng/Kconfig"

source "drivers/rtc/Kconfig"

source "drivers/scsi/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index 0befedd..0fa4413 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -117,4 +117,5 @@ obj-$(CONFIG_W1_EEPROM) += w1-eeprom/

obj-$(CONFIG_MACH_PIC32) += ddr/microchip/ obj-$(CONFIG_DM_HWSPINLOCK) += hwspinlock/ +obj-$(CONFIG_DM_RNG) += rng/ endif diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig new file mode 100644 index 0000000..dd44cc0 --- /dev/null +++ b/drivers/rng/Kconfig @@ -0,0 +1,7 @@ +config DM_RNG

•   bool "Driver support for Random Number Generator devices"
  

•   depends on DM
  

•   help
  

•     Enable driver model for random number generator(rng) devices.
  

•     This interface is used to initialise the rng device and to
  

•     read the random seed from the device.
  

diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile new file mode 100644 index 0000000..311705b --- /dev/null +++ b/drivers/rng/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (c) 2019, Linaro Limited +#

+obj-$(CONFIG_DM_RNG) += rng-uclass.o diff --git a/drivers/rng/rng-uclass.c b/drivers/rng/rng-uclass.c new file mode 100644 index 0000000..de745d3 --- /dev/null +++ b/drivers/rng/rng-uclass.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • Copyright (c) 2019, Linaro Limited
• */

+#include <common.h> +#include <dm.h> +#include <rng.h>

+int dm_rng_read(struct udevice *dev, void *buffer, size_t size) +{

•   const struct dm_rng_ops *ops = device_get_ops(dev);
  

•   if (!ops->read)
  

•           return -ENOSYS;
  

•   return ops->read(dev, buffer, size);
  

+}

+UCLASS_DRIVER(hwrng) = {

•   .name = "rng",
  

•   .id = UCLASS_RNG,
  

+}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index 0c563d8..192202d 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -86,6 +86,7 @@ enum uclass_id { UCLASS_REGULATOR, /* Regulator device */ UCLASS_REMOTEPROC, /* Remote Processor device */ UCLASS_RESET, /* Reset controller device */

•   UCLASS_RNG,             /* Random Number Generator */
    UCLASS_RTC,             /* Real time clock device */
    UCLASS_SCSI,            /* SCSI device */
    UCLASS_SERIAL,          /* Serial UART */
  

diff --git a/include/rng.h b/include/rng.h new file mode 100644 index 0000000..b5fd950 --- /dev/null +++ b/include/rng.h @@ -0,0 +1,25 @@ +#if !defined _RNG_H_ +#define _RNG_H_

+#include <dm.h>

Please don't include this in the header...just

struct udevice;

should do it.

+/**

• • dm_rng_read() - read a random number seed from the rng device

@dev

• • @buffer: input buffer to put the read random seed into
• • @size: number of bytes of random seed read

@return

• */

+int dm_rng_read(struct udevice *dev, void *buffer, size_t size);

+/* struct dm_rng_ops - Operations for the hwrng uclass */ +struct dm_rng_ops {

•   /**
  

•    * @read() - read a random number seed
  

•    *
  

@dev

•    * @data:       input buffer to read the random seed
  

•    * @max:        total number of bytes to read
  

@return

•    */
  

•   int (*read)(struct udevice *dev, void *data, size_t max);
  

+};

+#endif /* _RNG_H_ */

2.7.4

Regards, Simon

Hi Sughosh

On 12/4/19 12:53 PM, Sughosh Ganu wrote:

Add an entry for allowing clock enablement for the random number generator peripheral, RNG1.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

drivers/clk/clk_stm32mp1.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/clk/clk_stm32mp1.c b/drivers/clk/clk_stm32mp1.c index 3718970..da66bde 100644 --- a/drivers/clk/clk_stm32mp1.c +++ b/drivers/clk/clk_stm32mp1.c @@ -563,6 +563,7 @@ static const struct stm32mp1_clk_gate stm32mp1_clk_gate[] = { STM32MP1_CLK_SET_CLR(RCC_MP_AHB4ENSETR, 10, GPIOK, _UNKNOWN_SEL),

STM32MP1_CLK_SET_CLR(RCC_MP_AHB5ENSETR, 0, GPIOZ, _UNKNOWN_SEL),

• STM32MP1_CLK_SET_CLR(RCC_MP_AHB5ENSETR, 6, RNG1_K, _UNKNOWN_SEL),

  STM32MP1_CLK_SET_CLR(RCC_MP_AHB6ENSETR, 7, ETHCK_K, _ETH_SEL), STM32MP1_CLK_SET_CLR(RCC_MP_AHB6ENSETR, 8, ETHTX, _UNKNOWN_SEL),

Reviewed-by: Patrice Chotard patrice.chotard@st.com

Thanks

Hi Sughosh

On 12/4/19 12:53 PM, Sughosh Ganu wrote:

Add a driver for the rng device found on stm32mp1 platforms. The driver provides a routine for reading the random number seed from the hardware device.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

drivers/rng/Kconfig | 7 ++ drivers/rng/Makefile | 1 + drivers/rng/stm32mp1_rng.c | 164 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 172 insertions(+) create mode 100644 drivers/rng/stm32mp1_rng.c

diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig index dd44cc0..5fc11db 100644 --- a/drivers/rng/Kconfig +++ b/drivers/rng/Kconfig @@ -5,3 +5,10 @@ config DM_RNG Enable driver model for random number generator(rng) devices. This interface is used to initialise the rng device and to read the random seed from the device.

+config RNG_STM32MP1

•   bool "Enable random number generator for STM32MP1"
  

•   depends on ARCH_STM32MP && DM_RNG
  

•   default n
  

•   help
  

•     Enable STM32MP1 rng driver.
  

diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile index 311705b..699beb3 100644 --- a/drivers/rng/Makefile +++ b/drivers/rng/Makefile @@ -4,3 +4,4 @@ #

obj-$(CONFIG_DM_RNG) += rng-uclass.o +obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o diff --git a/drivers/rng/stm32mp1_rng.c b/drivers/rng/stm32mp1_rng.c new file mode 100644 index 0000000..f5ee084 --- /dev/null +++ b/drivers/rng/stm32mp1_rng.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/*

• • Copyright (c) 2019, Linaro Limited
• */

+#include <common.h> +#include <clk.h> +#include <dm.h> +#include <reset.h> +#include <rng.h>

+#include <asm/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h>

+#define RNG_CR 0x00 +#define RNG_CR_RNGEN BIT(2) +#define RNG_CR_CED BIT(5)

+#define RNG_SR 0x04 +#define RNG_SR_SEIS BIT(6) +#define RNG_SR_CEIS BIT(5) +#define RNG_SR_SECS BIT(2) +#define RNG_SR_DRDY BIT(0)

+#define RNG_DR 0x08

+struct stm32_rng_platdata {

• fdt_addr_t base;
• struct clk clk;
• struct reset_ctl rst;
• bool inited;

+};

+static int stm32_rng_read(struct udevice *dev, void *data, size_t len) +{

• int retval = 0, i;
• u32 sr, count, reg;
• size_t increment;
• struct stm32_rng_platdata *pdata = dev_get_platdata(dev);
• while (len > 0) {

• retval = readl_poll_timeout(pdata->base + RNG_SR, sr,
  

• 			    sr & RNG_SR_DRDY, 10000);
  

• if (retval)
  

• 	return retval;
  

• if (sr & (RNG_SR_SEIS | RNG_SR_SECS)) {
  

• 	/* As per SoC TRM */
  

• 	clrbits_le32(pdata->base + RNG_SR, RNG_SR_SEIS);
  

• 	for (i = 0; i < 12; i++)
  

• 		readl(pdata->base + RNG_DR);
  

• 	if (readl(pdata->base + RNG_SR) & RNG_SR_SEIS) {
  

• 		printf("RNG Noise");
  

• 		return -EIO;
  

• 	}
  

• 	/* start again */
  

• 	continue;
  

• }
  

• count = 4;
  

• while (len && count) {
  

• 	reg = readl(pdata->base + RNG_DR);
  

• 	memcpy(data, &reg, min(len, sizeof(u32)));
  

• 	increment = min(len, sizeof(u32));
  

• 	data += increment;
  

• 	retval += increment;
  

• 	len -= increment;
  

• 	count--;
  

• }
  

• }
• return retval;

+}

+static int stm32_rng_init(struct stm32_rng_platdata *pdata) +{

• int err;
• err = clk_enable(&pdata->clk);
• if (err)

• return err;
  

• /* Disable CED */
• writel(RNG_CR_RNGEN | RNG_CR_CED, pdata->base + RNG_CR);
• /* clear error indicators */
• writel(0, pdata->base + RNG_SR);
• pdata->inited = 1;
• return 0;

+}

+static int stm32_rng_cleanup(struct stm32_rng_platdata *pdata) +{

• writel(0, pdata->base + RNG_CR);
• return clk_disable(&pdata->clk);

+}

+static int stm32_rng_probe(struct udevice *dev) +{

• struct stm32_rng_platdata *pdata = dev_get_platdata(dev);
• if (pdata->inited)

• return 0;
  

No need to protect stm32_rng_probe() for re-entrance, DM is taking care of that, so pdata->inited field can be removed.

Thanks

• reset_assert(&pdata->rst);
• udelay(20);
• reset_deassert(&pdata->rst);
• return stm32_rng_init(pdata);

+}

+static int stm32_rng_remove(struct udevice *dev) +{

• struct stm32_rng_platdata *pdata = dev_get_platdata(dev);
• return stm32_rng_cleanup(pdata);

+}

+static int stm32_rng_ofdata_to_platdata(struct udevice *dev) +{

• struct stm32_rng_platdata *pdata = dev_get_platdata(dev);
• int err;
• pdata->base = dev_read_addr(dev);
• if (!pdata->base)

• return -ENOMEM;
  

• err = clk_get_by_index(dev, 0, &pdata->clk);
• if (err)

• return err;
  

• err = reset_get_by_index(dev, 0, &pdata->rst);
• if (err)

• return err;
  

• return 0;

+}

+static const struct dm_rng_ops stm32_rng_ops = {

• .read = stm32_rng_read,

+};

+static const struct udevice_id stm32_rng_match[] = {

• {

• .compatible = "st,stm32-rng",
  

• },
• {},

+};

+U_BOOT_DRIVER(stm32_rng) = {

• .name = "stm32-rng",
• .id = UCLASS_RNG,
• .of_match = stm32_rng_match,
• .ops = &stm32_rng_ops,
• .probe = stm32_rng_probe,
• .remove = stm32_rng_remove,
• .platdata_auto_alloc_size = sizeof(struct stm32_rng_platdata),
• .ofdata_to_platdata = stm32_rng_ofdata_to_platdata,

+};

On 12/4/19 12:53 PM, Sughosh Ganu wrote:

Enable support for random number generator on sandbox configs. This is aimed primarily at adding unit test support for rng uclass.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

configs/sandbox64_defconfig | 2 ++ configs/sandbox_defconfig | 2 ++ 2 files changed, 4 insertions(+)

diff --git a/configs/sandbox64_defconfig b/configs/sandbox64_defconfig index be1e103..b6596c4 100644 --- a/configs/sandbox64_defconfig +++ b/configs/sandbox64_defconfig @@ -157,6 +157,8 @@ CONFIG_REGULATOR_RK8XX=y CONFIG_REGULATOR_S5M8767=y CONFIG_DM_REGULATOR_SANDBOX=y CONFIG_REGULATOR_TPS65090=y +CONFIG_DM_RNG=y +CONFIG_RNG_SANDBOX=y CONFIG_DM_PWM=y CONFIG_PWM_SANDBOX=y CONFIG_RAM=y diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index eda595f..6fb3f00 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -178,6 +178,8 @@ CONFIG_REGULATOR_RK8XX=y CONFIG_REGULATOR_S5M8767=y CONFIG_DM_REGULATOR_SANDBOX=y CONFIG_REGULATOR_TPS65090=y +CONFIG_DM_RNG=y +CONFIG_RNG_SANDBOX=y CONFIG_DM_PWM=y CONFIG_PWM_SANDBOX=y CONFIG_RAM=y

Reviewed-by: Patrice Chotard patrice.chotard@st.com

Thanks