[U-Boot] [PATCH v2 u-boot 1/2] reset: Add get/assert/deassert/release for bulk of reset signals

Jean-Jacques Hiblot
2018-04-11T15:49:14Z

Hi Neil,

while trying to test your patches on dwc3, I ran into a compilation issue.

On 03/04/2018 11:40, Neil Armstrong wrote:
> This patch adds a "bulk" API to the reset API in order to get/deassert/
> assert/release a group of reset signals associated with a device.
>
> This bulk API will avoid adding a copy of the same code to manage
> a group of reset signals in drivers.
>
> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
> ---
> drivers/reset/reset-uclass.c | 60 +++++++++++++++++++++++++++
> include/reset.h | 99 ++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 159 insertions(+)
>
> diff --git a/drivers/reset/reset-uclass.c b/drivers/reset/reset-uclass.c
> index 307a297..9a5c9c9 100644
> --- a/drivers/reset/reset-uclass.c
> +++ b/drivers/reset/reset-uclass.c
> @@ -81,6 +81,40 @@ int reset_get_by_index(struct udevice *dev, int index,
> return 0;
> }
>
> +int reset_get_bulk(struct udevice *dev, struct reset_ctl_bulk *bulk)
> +{
> + int i, ret, err, count;
> +
> + bulk->count = 0;
> +
> + count = dev_count_phandle_with_args(dev, "resets", "#reset-cells");
> + if (!count)
> + return 0;
> +
> + bulk->resets = devm_kcalloc(dev, count, sizeof(struct reset_ctl),
> + GFP_KERNEL);
> + if (!bulk->resets)
> + return -ENOMEM;
> +
> + for (i = 0; i < count; i++) {
> + ret = reset_get_by_index(dev, i, &bulk->resets[i]);
> + if (ret < 0)
> + goto bulk_get_err;
> +
> + ++bulk->count;
> + }
> +
> + return 0;
> +
> +bulk_get_err:
> + err = reset_release_all(bulk->resets, bulk->count);
> + if (err)
> + debug("%s: could release all resets for %p\n",
> + __func__, dev);
> +
> + return ret;
> +}
> +
> int reset_get_by_name(struct udevice *dev, const char *name,
> struct reset_ctl *reset_ctl)
> {
> @@ -126,6 +160,19 @@ int reset_assert(struct reset_ctl *reset_ctl)
> return ops->rst_assert(reset_ctl);
> }
>
> +int reset_assert_bulk(struct reset_ctl_bulk *bulk)
> +{
> + int i, ret;
> +
> + for (i = 0; i < bulk->count; i++) {
> + ret = reset_assert(&bulk->resets[i]);
> + if (ret < 0)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> int reset_deassert(struct reset_ctl *reset_ctl)
> {
> struct reset_ops *ops = reset_dev_ops(reset_ctl->dev);
> @@ -135,6 +182,19 @@ int reset_deassert(struct reset_ctl *reset_ctl)
> return ops->rst_deassert(reset_ctl);
> }
>
> +int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
> +{
> + int i, ret;
> +
> + for (i = 0; i < bulk->count; i++) {
> + ret = reset_deassert(&bulk->resets[i]);
> + if (ret < 0)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> int reset_release_all(struct reset_ctl *reset_ctl, int count)
> {
> int i, ret;
> diff --git a/include/reset.h b/include/reset.h
> index 7185ade..d38f176 100644
> --- a/include/reset.h
> +++ b/include/reset.h
> @@ -60,6 +60,24 @@ struct reset_ctl {
> unsigned long id;
> };
>
> +/**
> + * struct reset_ctl_bulk - A handle to (allowing control of) a bulk of reset
> + * signals.
> + *
> + * Clients provide storage for the reset control bulk. The content of the
> + * structure is managed solely by the reset API. A reset control bulk struct is
> + * initialized by "get"ing the reset control bulk struct.
> + * The reset control bulk struct is passed to all other bulk reset APIs to apply
> + * the API to all the reset signals in the bulk struct.
> + *
> + * @resets: An array of reset signal handles handles.
> + * @count: The number of reset signal handles in the reset array.
> + */
> +struct reset_ctl_bulk {
> + struct reset_ctl *resets;
> + unsigned int count;
> +};
> +
> #ifdef CONFIG_DM_RESET
> /**
> * reset_get_by_index - Get/request a reset signal by integer index.
> @@ -81,6 +99,22 @@ int reset_get_by_index(struct udevice *dev, int index,
> struct reset_ctl *reset_ctl);
>
> /**
> + * reset_get_bulk - Get/request all reset signals of a device.
> + *
> + * This looks up and requests all reset signals of the client device; each
> + * device is assumed to have n reset signals associated with it somehow,
> + * and this function finds and requests all of them in a separate structure.
> + * The mapping of client device reset signals indices to provider reset signals
> + * may be via device-tree properties, board-provided mapping tables, or some
> + * other mechanism.
> + *
> + * @dev: The client device.
> + * @bulk A pointer to a reset control bulk struct to initialize.
> + * @return 0 if OK, or a negative error code.
> + */
> +int reset_get_bulk(struct udevice *dev, struct reset_ctl_bulk *bulk);
> +
> +/**
> * reset_get_by_name - Get/request a reset signal by name.
> *
> * This looks up and requests a reset signal. The name is relative to the
> @@ -132,6 +166,21 @@ int reset_free(struct reset_ctl *reset_ctl);
> int reset_assert(struct reset_ctl *reset_ctl);
>
> /**
> + * reset_assert_bulk - Assert all reset signals in a reset control bulk struct.
> + *
> + * This function will assert the specified reset signals in a reset control
> + * bulk struct, thus resetting the affected HW module(s). Depending on the
> + * reset controller hardware, the reset signals will either stay asserted
> + * until reset_deassert_bulk() is called, or the hardware may autonomously
> + * clear the reset signals itself.
> + *
> + * @bulk: A reset control bulk struct that was previously successfully
> + * requested by reset_get_bulk().
> + * @return 0 if OK, or a negative error code.
> + */
> +int reset_assert_bulk(struct reset_ctl_bulk *bulk);
> +
> +/**
> * reset_deassert - Deassert a reset signal.
> *
> * This function will deassert the specified reset signal, thus releasing the
> @@ -145,6 +194,20 @@ int reset_assert(struct reset_ctl *reset_ctl);
> int reset_deassert(struct reset_ctl *reset_ctl);
>
> /**
> + * reset_deassert_bulk - Deassert all reset signals in a reset control bulk
> + * struct.
> + *
> + * This function will deassert the specified reset signals in a reset control
> + * bulk struct, thus releasing the affected HW modules() from reset, and
> + * allowing them to continue normal operation.
> + *
> + * @bulk: A reset control bulk struct that was previously successfully
> + * requested by reset_get_bulk().
> + * @return 0 if OK, or a negative error code.
> + */
> +int reset_deassert_bulk(struct reset_ctl_bulk *bulk);
> +
> +/**
> * reset_release_all - Assert/Free an array of previously requested resets.
> *
> * For each reset contained in the reset array, this function will check if
> @@ -156,6 +219,23 @@ int reset_deassert(struct reset_ctl *reset_ctl);
> * @return 0 if OK, or a negative error code.
> */
> int reset_release_all(struct reset_ctl *reset_ctl, int count);
> +
> +/**
> + * reset_release_bulk - Assert/Free an array of previously requested reset
> + * signals in a reset control bulk struct.
> + *
> + * For each reset contained in the reset control bulk struct, this function
> + * will check if reset has been previously requested and then will assert
> + * and free it.
> + *
> + * @bulk: A reset control bulk struct that was previously successfully
> + * requested by reset_get_bulk().
> + * @return 0 if OK, or a negative error code.
> + */
> +static inline int reset_release_bulk(struct reset_ctl_bulk *bulk)
> +{
> + return reset_release_all(bulk->resets, bulk->count);
> +}
> #else
> static inline int reset_get_by_index(struct udevice *dev, int index,
> struct reset_ctl *reset_ctl)
> @@ -163,6 +243,11 @@ static inline int reset_get_by_index(struct udevice *dev, int index,
> return -ENOTSUPP;
> }
>
> +static inline int reset_get_bulk(struct udevice *dev, struct clk_bulk *bulk)
Should be struct reset_ctl_bulk instead of struct clk_bulk
> +{
> + return -ENOTSUPP;
> +}
> +
> static inline int reset_get_by_name(struct udevice *dev, const char *name,
> struct reset_ctl *reset_ctl)
> {
> @@ -179,16 +264,30 @@ static inline int reset_assert(struct reset_ctl *reset_ctl)
> return 0;
> }
>
> +static inline int reset_assert_bulk(struct reset_ctl_bulk *bulk)
> +{
> + return 0;
> +}
> +
> static inline int reset_deassert(struct reset_ctl *reset_ctl)
> {
> return 0;
> }
>
> +static inline int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
> +{
> + return 0;
> +}
> +
> static inline int reset_release_all(struct reset_ctl *reset_ctl, int count)
> {
> return 0;
> }
>
> +static inline int reset_release_bulk(struct clk_bulk *bulk)
ditto.

Jean-Jacques
> +{
> + return 0;
> +}
> #endif
>
> #endif