Re: [U-Boot] [PATCH 4/4] pinctrl: stm32: make pinctrl use hwspinlock

Hi Benjamin,

On 13 November 2018 at 01:51, Benjamin Gaignard benjamin.gaignard@linaro.org wrote:

From: Benjamin Gaignard benjamin.gaignard@linaro.org

Protect configuration registers with a hardware spinlock

Can you please add a bit more detail about what problem this fixes?

Signed-off-by: Benjamin Gaignard benjamin.gaignard@linaro.org

arch/arm/dts/stm32mp157c-ed1.dts | 4 ++++ drivers/pinctrl/pinctrl_stm32.c | 22 ++++++++++++++++++++++ 2 files changed, 26 insertions(+)

diff --git a/arch/arm/dts/stm32mp157c-ed1.dts b/arch/arm/dts/stm32mp157c-ed1.dts index fc277dd7d2..7a9b742d36 100644 --- a/arch/arm/dts/stm32mp157c-ed1.dts +++ b/arch/arm/dts/stm32mp157c-ed1.dts @@ -369,6 +369,10 @@ status = "okay"; };

+&pinctrl {

•   hwlocks = <&hwspinlock 0>;
  

+};

&usbphyc_port0 { phy-supply = <&vdd_usb>; vdda1v1-supply = <&reg11>; diff --git a/drivers/pinctrl/pinctrl_stm32.c b/drivers/pinctrl/pinctrl_stm32.c index 31285cdd57..469cc0c543 100644 --- a/drivers/pinctrl/pinctrl_stm32.c +++ b/drivers/pinctrl/pinctrl_stm32.c @@ -1,6 +1,7 @@ #include <common.h> #include <dm.h> #include <dm/pinctrl.h> +#include <hwspinlock.h> #include <asm/arch/gpio.h> #include <asm/gpio.h> #include <asm/io.h> @@ -19,12 +20,20 @@ static int stm32_gpio_config(struct gpio_desc *desc, { struct stm32_gpio_priv *priv = dev_get_priv(desc->dev); struct stm32_gpio_regs *regs = priv->regs;

•   struct hwspinlock *hws = dev_get_priv(desc->dev->parent);
    u32 index;
  

•   int ret;
  
    if (!ctl || ctl->af > 15 || ctl->mode > 3 || ctl->otype > 1 ||
        ctl->pupd > 2 || ctl->speed > 3)
            return -EINVAL;
  
  

•   ret = hwspinlock_lock_timeout(hws, 1);
  

•   if (ret == -ETIME) {
  

•           dev_err(desc->dev, "HWSpinlock timeout\n");
  

•           return ret;
  

•   }
  

•   index = (desc->offset & 0x07) * 4;
    clrsetbits_le32(&regs->afr[desc->offset >> 3], AFR_MASK << index,
                    ctl->af << index);
  

@@ -39,6 +48,8 @@ static int stm32_gpio_config(struct gpio_desc *desc, index = desc->offset; clrsetbits_le32(&regs->otyper, OTYPE_MSK << index, ctl->otype << index);

•   hwspinlock_unlock(hws);
  

•   return 0;
  

}

@@ -176,6 +187,15 @@ static int stm32_pinctrl_set_state_simple(struct udevice *dev, } #endif /* PINCTRL_FULL */

+static int stm32_pinctrl_probe(struct udevice *dev) +{

•   struct hwspinlock *hws = dev_get_priv(dev);
  

•   hwspinlock_get_by_index(dev, 0, hws);
  

Need to check return value

•   return 0;
  

+}

static struct pinctrl_ops stm32_pinctrl_ops = { #if CONFIG_IS_ENABLED(PINCTRL_FULL) .set_state = stm32_pinctrl_set_state, @@ -200,4 +220,6 @@ U_BOOT_DRIVER(pinctrl_stm32) = { .of_match = stm32_pinctrl_ids, .ops = &stm32_pinctrl_ops, .bind = dm_scan_fdt_dev,

•   .probe          = stm32_pinctrl_probe,
  

•   .priv_auto_alloc_size = sizeof(struct hwspinlock),
  

};

2.15.0

Regards, SImon