Re: [PATCH v4 1/2] firmware: xilinx: Add pm api function for PL config reg readback

From: Xu Yilun
Date: Mon Dec 26 2022 - 01:08:32 EST


On 2022-12-23 at 17:28:49 +0530, Nava kishore Manne wrote:
> Adds PM API for performing Programmable Logic(PL) configuration
> register readback. It provides an interface to the firmware(pmufw)
> to readback the FPGA configuration register.
>
> Signed-off-by: Nava kishore Manne <nava.kishore.manne@xxxxxxx>
> ---
> changes for v2:
> - None.
>
> Changes for v3:
> - Updated API and config reg read-back handling logic
> - Updated the commit msg to align with the changes.
>
> Changes for v4:
> - Fix some minor coding issues. No functional changes.
> - Updated Return value comments as suggested by Xu Yilun.
>
> drivers/firmware/xilinx/zynqmp.c | 33 ++++++++++++++++++++++++++++
> include/linux/firmware/xlnx-zynqmp.h | 10 +++++++++
> 2 files changed, 43 insertions(+)
>
> diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
> index ff5cabe70a2b..ca954e1119b5 100644
> --- a/drivers/firmware/xilinx/zynqmp.c
> +++ b/drivers/firmware/xilinx/zynqmp.c
> @@ -941,6 +941,39 @@ int zynqmp_pm_fpga_get_status(u32 *value)
> }
> EXPORT_SYMBOL_GPL(zynqmp_pm_fpga_get_status);
>
> +/**
> + * zynqmp_pm_fpga_get_config_status - Get the FPGA configuration status.
> + * @value: Buffer to store FPGA configuration status.
> + *
> + * This function provides access to the pmufw to get the FPGA configuration
> + * status
> + *
> + * Return: 0 on success, a negative value on error
> + */
> +int zynqmp_pm_fpga_get_config_status(u32 *value)
> +{
> + u32 buf, phys_lower_addr, phys_upper_addr;

Why naming them phys_xxx?

> + u32 ret_payload[PAYLOAD_ARG_CNT];
> + int ret;
> +
> + if (!value)
> + return -EINVAL;
> +
> + phys_lower_addr = lower_32_bits((u64)&buf);
> + phys_upper_addr = upper_32_bits((u64)&buf);
> +
> + ret = zynqmp_pm_invoke_fn(PM_FPGA_READ,
> + XILINX_ZYNQMP_PM_FPGA_CONFIG_STAT_OFFSET,
> + phys_lower_addr, phys_upper_addr,
> + XILINX_ZYNQMP_PM_FPGA_READ_CONFIG_REG,
> + ret_payload);
> +
> + *value = ret_payload[1];
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(zynqmp_pm_fpga_get_config_status);
> +
> /**
> * zynqmp_pm_pinctrl_request - Request Pin from firmware
> * @pin: Pin number to request
> diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h
> index 76d2b3ebad84..29e8964f4297 100644
> --- a/include/linux/firmware/xlnx-zynqmp.h
> +++ b/include/linux/firmware/xlnx-zynqmp.h
> @@ -70,6 +70,10 @@
> #define XILINX_ZYNQMP_PM_FPGA_FULL 0x0U
> #define XILINX_ZYNQMP_PM_FPGA_PARTIAL BIT(0)
>
> +/* FPGA Status Reg */
> +#define XILINX_ZYNQMP_PM_FPGA_CONFIG_STAT_OFFSET 7U
> +#define XILINX_ZYNQMP_PM_FPGA_READ_CONFIG_REG 0U
> +
> /*
> * Node IDs for the Error Events.
> */
> @@ -117,6 +121,7 @@ enum pm_api_id {
> PM_CLOCK_GETRATE = 42,
> PM_CLOCK_SETPARENT = 43,
> PM_CLOCK_GETPARENT = 44,
> + PM_FPGA_READ = 46,
> PM_SECURE_AES = 47,
> PM_FEATURE_CHECK = 63,
> };
> @@ -505,6 +510,7 @@ int zynqmp_pm_register_sgi(u32 sgi_num, u32 reset);
> int zynqmp_pm_set_sd_config(u32 node, enum pm_sd_config_type config, u32 value);
> int zynqmp_pm_set_gem_config(u32 node, enum pm_gem_config_type config,
> u32 value);
> +int zynqmp_pm_fpga_get_config_status(u32 *value);

Is it better put it along with zynqmp_pm_fpga_get_status()?

Thanks,
Yilun

> #else
> static inline int zynqmp_pm_get_api_version(u32 *version)
> {
> @@ -790,6 +796,10 @@ static inline int zynqmp_pm_set_gem_config(u32 node,
> return -ENODEV;
> }
>
> +static inline int zynqmp_pm_fpga_get_config_status(u32 *value)
> +{
> + return -ENODEV;
> +}
> #endif
>
> #endif /* __FIRMWARE_ZYNQMP_H__ */
> --
> 2.25.1
>