[PATCH 2/4] fpga mgr: Expose FPGA capabilities to userland via sysfs

atull
2016-11-14T14:33:31Z

On Mon, 7 Nov 2016, Moritz Fischer wrote:

Hi Moritz,

One nit below. Otherwise,

Acked-by: Alan Tull <atull@opensource.altera.com>

Alan

> Expose FPGA capabilities to userland via sysfs.
>
> Add Documentation for currently supported capabilities
> that get exported via sysfs.
>
> Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
> Cc: Alan Tull <atull@opensource.altera.com>
> Cc: Michal Simek <michal.simek@xilinx.com>
> Cc: S?ren Brinkmann <soren.brinkmann@xilinx.com>
> Cc: linux-kernel at vger.kernel.org
> Cc: linux-arm-kernel at lists.infradead.org
> ---
> Documentation/ABI/testing/sysfs-class-fpga-manager | 16 ++++++++++++++++
> drivers/fpga/fpga-mgr.c | 20 ++++++++++++++++++++
> include/linux/fpga/fpga-mgr.h | 2 ++
> 3 files changed, 38 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-class-fpga-manager b/Documentation/ABI/testing/sysfs-class-fpga-manager
> index 23056c5..d9aee21 100644
> --- a/Documentation/ABI/testing/sysfs-class-fpga-manager
> +++ b/Documentation/ABI/testing/sysfs-class-fpga-manager
> @@ -35,3 +35,19 @@ Description: Read fpga manager state as a string.
> * write complete = Doing post programming steps
> * write complete error = Error while doing post programming
> * operating = FPGA is programmed and operating
> +
> +What: /sys/class/fpga_manager/fpga/capabilities
> +Date: November 2016
> +KernelVersion: 4.9
> +Contact: Moritz Fischer <moritz.fischer@ettus.com>
> +Description: Read fpga manager capabilities as a string.
> + The intent is to provide userspace with information on what
> + operations the particular instance can execute.
> +
> + Each line expresses a capability that is available on the
> + particular instance of an fpga manager.
> + Supported so far:
> +
> + * Full reconfiguration
> + * Partial reconfiguration
> + * Decrypt bitstream on the fly

Decrypt gets added in a later patch.

> diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
> index ed57c17..98230b7 100644
> --- a/drivers/fpga/fpga-mgr.c
> +++ b/drivers/fpga/fpga-mgr.c
> @@ -167,6 +167,11 @@ static const char * const state_str[] = {
> [FPGA_MGR_STATE_OPERATING] = "operating",
> };
>
> +static const char * const cap_str[] = {
> + [FPGA_MGR_CAP_FULL_RECONF] = "Full reconfiguration",
> + [FPGA_MGR_CAP_PARTIAL_RECONF] = "Partial reconfiguration",
> +};
> +
> static ssize_t name_show(struct device *dev,
> struct device_attribute *attr, char *buf)
> {
> @@ -183,10 +188,25 @@ static ssize_t state_show(struct device *dev,
> return sprintf(buf, "%s\n", state_str[mgr->state]);
> }
>
> +static ssize_t capabilities_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct fpga_manager *mgr = to_fpga_manager(dev);
> + char *start = buf;
> + enum fpga_mgr_capability cap;
> +
> + for_each_fpga_mgr_cap_mask(cap, mgr->caps)
> + buf += sprintf(buf, "%s\n", cap_str[cap]);
> +
> + return buf - start;
> +}
> +
> +static DEVICE_ATTR_RO(capabilities);
> static DEVICE_ATTR_RO(name);
> static DEVICE_ATTR_RO(state);
>
> static struct attribute *fpga_mgr_attrs[] = {
> + &dev_attr_capabilities.attr,
> &dev_attr_name.attr,
> &dev_attr_state.attr,
> NULL,
> diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
> index e73429c..9bb96a5 100644
> --- a/include/linux/fpga/fpga-mgr.h
> +++ b/include/linux/fpga/fpga-mgr.h
> @@ -108,6 +108,8 @@ static inline void __fpga_mgr_cap_set(enum fpga_mgr_capability cap,
> set_bit(cap, mask->bits);
> }
>
> +#define for_each_fpga_mgr_cap_mask(cap, mask) \
> + for_each_set_bit(cap, mask.bits, FPGA_MGR_CAP_END)
>
> /**
> * struct fpga_manager_ops - ops for low level fpga manager drivers
> --
> 2.10.0
>
>