Re: [PATCH] drivers: firmware: xilinx: Add support for feature check

[Michal Simek]

On 12. 11. 19 9:35, Rajan Vaja wrote:
> From: Ravi Patel <ravi.patel@xxxxxxxxxx>
> 
> Query for corresponding feature before calling EEMI API
> from the driver.
> 
> Signed-off-by: Ravi Patel <ravi.patel@xxxxxxxxxx>
> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
> Signed-off-by: Rajan Vaja <rajan.vaja@xxxxxxxxxx>
> ---
>  drivers/firmware/xilinx/zynqmp.c     | 43 ++++++++++++++++++++++++++++++++++++
>  include/linux/firmware/xlnx-zynqmp.h |  7 ++++++
>  2 files changed, 50 insertions(+)
> 
> diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
> index 74d9f13..ecc339d 100644
> --- a/drivers/firmware/xilinx/zynqmp.c
> +++ b/drivers/firmware/xilinx/zynqmp.c
> @@ -26,6 +26,9 @@
>  
>  static const struct zynqmp_eemi_ops *eemi_ops_tbl;
>  
> +static bool feature_check_enabled;
> +static u32 zynqmp_pm_features[PM_API_MAX];
> +
>  static const struct mfd_cell firmware_devs[] = {
>  	{
>  		.name = "zynqmp_power_controller",
> @@ -44,6 +47,8 @@ static int zynqmp_pm_ret_code(u32 ret_status)
>  	case XST_PM_SUCCESS:
>  	case XST_PM_DOUBLE_REQ:
>  		return 0;
> +	case XST_PM_NO_FEATURE:
> +		return -ENOTSUPP;
>  	case XST_PM_NO_ACCESS:
>  		return -EACCES;
>  	case XST_PM_ABORT_SUSPEND:
> @@ -129,6 +134,39 @@ static noinline int do_fw_call_hvc(u64 arg0, u64 arg1, u64 arg2,
>  }
>  
>  /**
> + * zynqmp_pm_feature() - Check weather given feature is supported or not
> + * @api_id:		API ID to check
> + *
> + * Return: Returns status, either success or error+reason
> + */
> +static int zynqmp_pm_feature(u32 api_id)
> +{
> +	int ret;
> +	u32 ret_payload[PAYLOAD_ARG_CNT];
> +	u64 smc_arg[2];
> +
> +	if (!feature_check_enabled)
> +		return 0;
> +
> +	/* Return value if feature is already checked */
> +	if (zynqmp_pm_features[api_id] != PM_FEATURE_UNCHECKED)
> +		return zynqmp_pm_features[api_id];
> +
> +	smc_arg[0] = PM_SIP_SVC | PM_FEATURE_CHECK;
> +	smc_arg[1] = api_id;
> +
> +	ret = do_fw_call(smc_arg[0], smc_arg[1], 0, ret_payload);
> +	if (ret) {
> +		zynqmp_pm_features[api_id] = PM_FEATURE_INVALID;
> +		return PM_FEATURE_INVALID;
> +	}
> +
> +	zynqmp_pm_features[api_id] = ret_payload[1];
> +
> +	return zynqmp_pm_features[api_id];
> +}
> +
> +/**
>   * zynqmp_pm_invoke_fn() - Invoke the system-level platform management layer
>   *			   caller function depending on the configuration
>   * @pm_api_id:		Requested PM-API call
> @@ -162,6 +200,9 @@ int zynqmp_pm_invoke_fn(u32 pm_api_id, u32 arg0, u32 arg1,
>  	 */
>  	u64 smc_arg[4];
>  
> +	if (zynqmp_pm_feature(pm_api_id) == PM_FEATURE_INVALID)
> +		return -ENOTSUPP;
> +
>  	smc_arg[0] = PM_SIP_SVC | pm_api_id;
>  	smc_arg[1] = ((u64)arg1 << 32) | arg0;
>  	smc_arg[2] = ((u64)arg3 << 32) | arg2;
> @@ -717,6 +758,8 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
>  		np = of_find_compatible_node(NULL, NULL, "xlnx,versal");
>  		if (!np)
>  			return 0;
> +
> +		feature_check_enabled = true;
>  	}
>  	of_node_put(np);
>  
> diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h
> index 74d710d..f0d4558 100644
> --- a/include/linux/firmware/xlnx-zynqmp.h
> +++ b/include/linux/firmware/xlnx-zynqmp.h
> @@ -48,6 +48,10 @@
>  #define	ZYNQMP_PM_CAPABILITY_WAKEUP	0x4U
>  #define	ZYNQMP_PM_CAPABILITY_UNUSABLE	0x8U
>  
> +/* Feature check status */
> +#define PM_FEATURE_INVALID		-1
> +#define PM_FEATURE_UNCHECKED		0
> +
>  /*
>   * Firmware FPGA Manager flags
>   * XILINX_ZYNQMP_PM_FPGA_FULL:	FPGA full reconfiguration
> @@ -78,11 +82,14 @@ enum pm_api_id {
>  	PM_CLOCK_GETRATE,
>  	PM_CLOCK_SETPARENT,
>  	PM_CLOCK_GETPARENT,
> +	PM_FEATURE_CHECK = 63,
> +	PM_API_MAX,
>  };
>  
>  /* PMU-FW return status codes */
>  enum pm_ret_status {
>  	XST_PM_SUCCESS = 0,
> +	XST_PM_NO_FEATURE = 19,
>  	XST_PM_INTERNAL = 2000,
>  	XST_PM_CONFLICT,
>  	XST_PM_NO_ACCESS,
> 

Applied to zynqmp/soc branch and queue to v5.6.

Thanks,
Michal