[PATCH] arm: socfpga: Ensure FPGA in user mode before enabling the bridges

[Chee, Tien Fong]

Hi Dinesh,

On 4/3/2026 11:43 am, dinesh.maniyam at altera.com wrote:
> From: Dinesh Maniyam <dinesh.maniyam at altera.com>
>
> Unexpected behavior and error can occur if FPGA is accessed in unknown
> state.Always checking with FPGA in user mode is required to ensure
> system stability.
>
> Signed-off-by: Tien Fong Chee <tien.fong.chee at intel.com>
> Signed-off-by: Dinesh Maniyam <dinesh.maniyam at altera.com>
> ---
>   arch/arm/mach-socfpga/misc_arria10.c | 13 ++++++++++---
>   1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-socfpga/misc_arria10.c b/arch/arm/mach-socfpga/misc_arria10.c
> index 7e0f3875b7c..6b25ab917ca 100644
> --- a/arch/arm/mach-socfpga/misc_arria10.c
> +++ b/arch/arm/mach-socfpga/misc_arria10.c
> @@ -13,6 +13,7 @@
>   #include <ns16550.h>
>   #include <spi_flash.h>
>   #include <watchdog.h>
> +#include <asm/arch/fpga_manager.h>
>   #include <asm/arch/misc.h>
>   #include <asm/arch/pinmux.h>
>   #include <asm/arch/reset_manager.h>
> @@ -126,10 +127,16 @@ int print_cpuinfo(void)
>   
>   void do_bridge_reset(int enable, unsigned int mask)


mask is unused on Arria 10—please mark it __maybe_unused so we do not 
trip -Wunused-parameter while keeping the shared API.

Example: unsigned int mask __maybe_unused


>   {
> -	if (enable)
> -		socfpga_reset_deassert_bridges_handoff();
> -	else
> +	if (enable) {
> +		if (is_fpgamgr_user_mode()) {
> +			socfpga_reset_deassert_bridges_handoff();
> +		} else {
> +			puts("Bridges: Failed to enable because FPGA is not ");
> +			puts("in user mode\n");


Single line puts is preferred

Example:
         puts("Bridges: failed to enable because FPGA is not "
                 "in user mode\n");

Best regards,

Tien Fong