[U-Boot] [PATCH v2 3/4] hwspinlock: add stm32 hardware spinlock support

[Patrice CHOTARD]

Hi Benjamin

On 11/14/18 10:01 AM, Benjamin Gaignard wrote:
> Implement hardware spinlock support for STM32MP1.
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard at st.com>
> ---
> version 2:
> - remove useless include
> - add a private structure to store base address
> - be more verbose in configuration flag description
> 
>  arch/arm/dts/stm32mp157c-ed1.dts      |  4 ++
>  arch/arm/dts/stm32mp157c.dtsi         |  9 ++++
>  configs/stm32mp15_basic_defconfig     |  2 +
>  drivers/hwspinlock/Kconfig            |  8 +++
>  drivers/hwspinlock/Makefile           |  1 +
>  drivers/hwspinlock/stm32_hwspinlock.c | 92 +++++++++++++++++++++++++++++++++++
>  6 files changed, 116 insertions(+)
>  create mode 100644 drivers/hwspinlock/stm32_hwspinlock.c
> 
> diff --git a/arch/arm/dts/stm32mp157c-ed1.dts b/arch/arm/dts/stm32mp157c-ed1.dts
> index f8b7701167..fc277dd7d2 100644
> --- a/arch/arm/dts/stm32mp157c-ed1.dts
> +++ b/arch/arm/dts/stm32mp157c-ed1.dts
> @@ -365,6 +365,10 @@
>  	usb33d-supply = <&usb33>;
>  };
>  
> +&hwspinlock {
> +	status = "okay";
> +};
> +
>  &usbphyc_port0 {
>  	phy-supply = <&vdd_usb>;
>  	vdda1v1-supply = <&reg11>;
> diff --git a/arch/arm/dts/stm32mp157c.dtsi b/arch/arm/dts/stm32mp157c.dtsi
> index 33c5981869..37cadfa30c 100644
> --- a/arch/arm/dts/stm32mp157c.dtsi
> +++ b/arch/arm/dts/stm32mp157c.dtsi
> @@ -690,6 +690,15 @@
>  			status = "disabled";
>  		};
>  
> +		hwspinlock: hwspinlock at 4c000000 {
> +			compatible = "st,stm32-hwspinlock";
> +			#hwlock-cells = <1>;
> +			reg = <0x4c000000 0x400>;
> +			clocks = <&rcc HSEM>;
> +			clock-names = "hwspinlock";
> +			status = "disabled";
> +		};
> +
>  		rcc: rcc at 50000000 {
>  			compatible = "st,stm32mp1-rcc", "syscon";
>  			reg = <0x50000000 0x1000>;
> diff --git a/configs/stm32mp15_basic_defconfig b/configs/stm32mp15_basic_defconfig
> index 3bf7538089..c8409fd04e 100644
> --- a/configs/stm32mp15_basic_defconfig
> +++ b/configs/stm32mp15_basic_defconfig
> @@ -32,6 +32,8 @@ CONFIG_CMD_EXT4_WRITE=y
>  # CONFIG_SPL_DOS_PARTITION is not set
>  CONFIG_DEFAULT_DEVICE_TREE="stm32mp157c-ev1"
>  CONFIG_STM32_ADC=y
> +CONFIG_DM_HWSPINLOCK=y
> +CONFIG_HWSPINLOCK_STM32=y
>  CONFIG_DM_I2C=y
>  CONFIG_SYS_I2C_STM32F7=y
>  CONFIG_LED=y
> diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
> index de367fd2a9..96d4f5d6ca 100644
> --- a/drivers/hwspinlock/Kconfig
> +++ b/drivers/hwspinlock/Kconfig
> @@ -13,4 +13,12 @@ config HWSPINLOCK_SANDBOX
>  	  can be probed and support all the methods of HWSPINLOCK, but does not
>  	  really do anything.
>  
> +config HWSPINLOCK_STM32
> +	bool "Enable Hardware Spinlock support for STM32"
> +	depends on ARCH_STM32MP && DM_HWSPINLOCK
> +	help
> +	  Enable hardware spinlock support in STM32MP. Hardware spinlocks are
> +	  hardware mutex which provide a synchronisation mechanism for the
> +	  various processors on the SoC.
> +
>  endmenu
> diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
> index 2704d6814f..289b12a256 100644
> --- a/drivers/hwspinlock/Makefile
> +++ b/drivers/hwspinlock/Makefile
> @@ -4,3 +4,4 @@
>  
>  obj-$(CONFIG_DM_HWSPINLOCK) += hwspinlock-uclass.o
>  obj-$(CONFIG_HWSPINLOCK_SANDBOX) += sandbox_hwspinlock.o
> +obj-$(CONFIG_HWSPINLOCK_STM32) += stm32_hwspinlock.o
> diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c
> new file mode 100644
> index 0000000000..a32bde4906
> --- /dev/null
> +++ b/drivers/hwspinlock/stm32_hwspinlock.c
> @@ -0,0 +1,92 @@
> +// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
> +/*
> + * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
> + */
> +
> +#include <common.h>
> +#include <clk.h>
> +#include <dm.h>
> +#include <hwspinlock.h>
> +#include <asm/io.h>
> +
> +#define STM32_MUTEX_COREID	BIT(8)
> +#define STM32_MUTEX_LOCK_BIT	BIT(31)
> +#define STM32_MUTEX_NUM_LOCKS	32
> +
> +struct stm32mp1_hws_priv {
> +	fdt_addr_t base;
> +};
> +
> +static int stm32mp1_lock(struct udevice *dev, int index)
> +{
> +	struct stm32mp1_hws_priv *priv = dev_get_priv(dev);
> +	u32 status;
> +
> +	if (index >= STM32_MUTEX_NUM_LOCKS)
> +		return -EINVAL;
> +
> +	status = readl(priv->base + index * sizeof(u32));
> +	if (status == (STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID))
> +		return -EBUSY;
> +
> +	writel(STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID,
> +	       priv->base + index * sizeof(u32));
> +
> +	status = readl(priv->base + index * sizeof(u32));
> +	if (status != (STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID))
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static int stm32mp1_unlock(struct udevice *dev, int index)
> +{
> +	struct stm32mp1_hws_priv *priv = dev_get_priv(dev);
> +
> +	if (index >= STM32_MUTEX_NUM_LOCKS)
> +		return -EINVAL;
> +
> +	writel(STM32_MUTEX_COREID, priv->base + index * sizeof(u32));
> +
> +	return 0;
> +}
> +
> +static int stm32mp1_hwspinlock_probe(struct udevice *dev)
> +{
> +	struct stm32mp1_hws_priv *priv = dev_get_priv(dev);
> +	struct clk clk;
> +	int ret;
> +
> +	priv->base = dev_read_addr(dev);
> +	if (priv->base == FDT_ADDR_T_NONE)
> +		return -EINVAL;
> +
> +	ret = clk_get_by_index(dev, 0, &clk);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_enable(&clk);
> +	if (ret)
> +		clk_free(&clk);
> +
> +	return ret;
> +}
> +
> +static const struct hwspinlock_ops stm32mp1_hwspinlock_ops = {
> +	.lock = stm32mp1_lock,
> +	.unlock = stm32mp1_unlock,
> +};
> +
> +static const struct udevice_id stm32mp1_hwspinlock_ids[] = {
> +	{ .compatible = "st,stm32-hwspinlock" },
> +	{}
> +};
> +
> +U_BOOT_DRIVER(hwspinlock_stm32mp1) = {
> +	.name = "hwspinlock_stm32mp1",
> +	.id = UCLASS_HWSPINLOCK,
> +	.of_match = stm32mp1_hwspinlock_ids,
> +	.ops = &stm32mp1_hwspinlock_ops,
> +	.probe = stm32mp1_hwspinlock_probe,
> +	.priv_auto_alloc_size = sizeof(struct stm32mp1_hws_priv),
> +};
> 


Reviewed-by: Patrice Chotard <patrice.chotard at st.com>

Thanks