[U-Boot] [PATCH v2 1/6] dm: SMEM (Shared memory) uclass
Simon Glass
sjg at chromium.org
Tue Jun 26 03:59:05 UTC 2018
Hi Ramon,
On 21 June 2018 at 20:11, Ramon Fried <ramon.fried at gmail.com> wrote:
> This is a uclass for Shared memory manager drivers.
>
> A Shared Memory Manager driver implements an interface for allocating
> and accessing items in the memory area shared among all of the
> processors.
>
> Signed-off-by: Ramon Fried <ramon.fried at gmail.com>
>
> ---
>
> Changes in v2:
> (As suggested by Simon Glass)
> - Introduced a new dm class (CLASS_SMEM) instead of CLASS_SOC.
> - Added sandbox driver
> - Added testing for DM class.
>
> drivers/Makefile | 1 +
> drivers/smem/Kconfig | 2 +
> drivers/smem/Makefile | 5 +++
> drivers/smem/smem-uclass.c | 53 ++++++++++++++++++++++++
> include/dm/uclass-id.h | 1 +
> include/smem.h | 84 ++++++++++++++++++++++++++++++++++++++
> 6 files changed, 146 insertions(+)
> create mode 100644 drivers/smem/Kconfig
> create mode 100644 drivers/smem/Makefile
> create mode 100644 drivers/smem/smem-uclass.c
> create mode 100644 include/smem.h
>
Reviewed-by: Simon Glass <sjg at chromium.org>
A few nits below.
> diff --git a/drivers/Makefile b/drivers/Makefile
> index a213ea9671..ba4a561358 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -98,6 +98,7 @@ obj-y += pwm/
> obj-y += reset/
> obj-y += input/
> # SOC specific infrastructure drivers.
> +obj-y += smem/
> obj-y += soc/
> obj-$(CONFIG_REMOTEPROC) += remoteproc/
> obj-y += thermal/
> diff --git a/drivers/smem/Kconfig b/drivers/smem/Kconfig
> new file mode 100644
> index 0000000000..64337a8b8e
> --- /dev/null
> +++ b/drivers/smem/Kconfig
> @@ -0,0 +1,2 @@
> +menuconfig SMEM
> + bool "SMEM (Shared Memory mamanger) support"
> diff --git a/drivers/smem/Makefile b/drivers/smem/Makefile
> new file mode 100644
> index 0000000000..ca55c4512d
> --- /dev/null
> +++ b/drivers/smem/Makefile
> @@ -0,0 +1,5 @@
> +# SPDX-License-Identifier: GPL-2.0+
> +#
> +# Makefile for the U-Boot SMEM interface drivers
> +
> +obj-$(CONFIG_SMEM) += smem-uclass.o
> diff --git a/drivers/smem/smem-uclass.c b/drivers/smem/smem-uclass.c
> new file mode 100644
> index 0000000000..07ed1a92d8
> --- /dev/null
> +++ b/drivers/smem/smem-uclass.c
> @@ -0,0 +1,53 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) 2018 Ramon Fried <ramon.fried at gmail.com>
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <smem.h>
> +
> +int smem_alloc(struct udevice *dev, unsigned int host,
> + unsigned int item, size_t size)
> +{
> + struct smem_ops *ops = smem_get_ops(dev);
> +
> + if (!ops->alloc)
> + return -ENOSYS;
> +
> + return ops->alloc(host, item, size);
> +}
> +
> +void *smem_get(struct udevice *dev, unsigned int host,
> + unsigned int item, size_t *size)
> +{
> + struct smem_ops *ops = smem_get_ops(dev);
> +
> + if (!ops->get)
> + return NULL;
> +
> + return ops->get(host, item, size);
> +}
> +
> +int smem_get_free_space(struct udevice *dev, unsigned int host, size_t *free)
> +{
> + struct smem_ops *ops = smem_get_ops(dev);
> +
> + int ret;
> +
> + if (!ops->get_free_space)
> + return -ENOSYS;
> +
> + ret = ops->get_free_space(host);
> + if (ret > 0)
> + *free = ret;
> + else
> + return ret;
It seems odd that get_free_space() has a different return value than
smem_get_free_space(). Can you make the latter return the amount of
free space? If not, change the op to return it in a param. You can use
long as the return value if that helps.
> +
> + return 0;
> +}
> +
> +UCLASS_DRIVER(smem) = {
> + .id = UCLASS_SMEM,
> + .name = "smem",
> +};
> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
> index d7f9df3583..a39643ec5e 100644
> --- a/include/dm/uclass-id.h
> +++ b/include/dm/uclass-id.h
> @@ -74,6 +74,7 @@ enum uclass_id {
> UCLASS_RTC, /* Real time clock device */
> UCLASS_SCSI, /* SCSI device */
> UCLASS_SERIAL, /* Serial UART */
> + UCLASS_SMEM, /* Shared memory interface */
> UCLASS_SPI, /* SPI bus */
> UCLASS_SPMI, /* System Power Management Interface bus */
> UCLASS_SPI_FLASH, /* SPI flash */
> diff --git a/include/smem.h b/include/smem.h
> new file mode 100644
> index 0000000000..201960232c
> --- /dev/null
> +++ b/include/smem.h
> @@ -0,0 +1,84 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * header file for smem driver.
If you have a README somewhere please point to it here.
> + *
> + * Copyright (c) 2018 Ramon Fried <ramon.fried at gmail.com>
> + */
> +
> +#ifndef _smemh_
> +#define _smemh_
> +
> +/* struct smem_ops: Operations for the SMEM uclass */
> +struct smem_ops {
> + /**
> + * alloc() - allocate space for a smem item
> + *
> + * @host: remote processor id, or -1
What does -1 mean? Please expand commment
> + * @item: smem item handle
How does one choose this? What does it mean? Can you expand this comment a bit?
> + * @size: number of bytes to be allocated
> + * @return 0 if OK, -ve on error
> + */
> + int (*alloc)(unsigned int host,
> + unsigned int item, size_t size);
Fits on one line?
> +
> + /**
> + * get() - Resolve ptr of size of a smem item
> + *
> + * @host: the remote processor, of -1
> + * @item: smem item handle
> + * @size: pointer to be filled out with the size of the item
> + * @return pointer on success, NULL on error
> + */
> + void *(*get)(unsigned int host,
> + unsigned int item, size_t *size);
Fits on one line?
> +
> + /**
> + * get_free_space() - Set the PWM invert
> + *
> + * @host: the remote processor identifying a partition, or -1
> + * @return free space, -ve on error
free space in bytes ?
> + */
> + int (*get_free_space)(unsigned int host);
> +};
> +
> +#define smem_get_ops(dev) ((struct smem_ops *)(dev)->driver->ops)
> +
> +/**
> + * smem_alloc() - allocate space for a smem item
> + * @host: remote processor id, or -1
> + * @item: smem item handle
> + * @size: number of bytes to be allocated
> + * @return 0 if OK, -ve on error
> + *
> + * Allocate space for a given smem item of size @size, given that the item is
> + * not yet allocated.
> + */
> +int smem_alloc(struct udevice *dev, unsigned int host,
> + unsigned int item, size_t size);
> +
> +/**
> + * smem_get() - resolve ptr of size of a smem item
> + * @host: the remote processor, or -1
> + * @item: smem item handle
> + * @size: pointer to be filled out with size of the item
> + * @return pointer on success, NULL on error
> + *
> + * Looks up smem item and returns pointer to it. Size of smem
> + * item is returned in @size.
> + */
> +void *smem_get(struct udevice *dev, unsigned int host,
> + unsigned int item, size_t *size);
> +
> +/**
> + * smem_get_free_space() - retrieve amount of free space in a partition
> + * @host: the remote processor identifying a partition, or -1
> + * @free_space: pointer to be filled out with free space
> + * @return 0 if OK, -ve on error
> + *
> + * To be used by smem clients as a quick way to determine if any new
> + * allocations has been made.
> + */
> +int smem_get_free_space(struct udevice *dev, unsigned int host, size_t *free_space);
> +
> +#endif /* _smem_h_ */
> +
> --
> 2.17.1
>
Regards,
Simon
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