[PATCH] drivers: fpga: intel_sdm_mb: Flush cache before FPGA configuration

[Michal Simek]

On 5/6/25 03:28, Naresh Kumar Ravulapalli wrote:
> FPGA configuration encounters failure when the cache is not flushed.
> Add cache flushing to the memory region that holds the FPGA
> configuration bitstream.
> 
> Signed-off-by: Naresh Kumar Ravulapalli <nareshkumar.ravulapalli at altera.com>
> ---
>   drivers/fpga/intel_sdm_mb.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/fpga/intel_sdm_mb.c b/drivers/fpga/intel_sdm_mb.c
> index 5fe4dbdfd32..a2f3b160a73 100644
> --- a/drivers/fpga/intel_sdm_mb.c
> +++ b/drivers/fpga/intel_sdm_mb.c
> @@ -1,6 +1,7 @@
>   // SPDX-License-Identifier: GPL-2.0+
>   /*
>    * Copyright (C) 2018 Intel Corporation <www.intel.com>
> + * Copyright (C) 2025 Altera Corporation <www.altera.com>
>    */
>   
>   #include <altera.h>
> @@ -9,6 +10,8 @@
>   #include <watchdog.h>
>   #include <asm/arch/mailbox_s10.h>
>   #include <asm/arch/smc_api.h>
> +#include <asm/cache.h>
> +#include <cpu_func.h>
>   #include <linux/delay.h>
>   #include <linux/errno.h>
>   #include <linux/intel-smc.h>
> @@ -738,6 +741,8 @@ int intel_sdm_mb_load(Altera_desc *desc, const void *rbf_data, size_t rbf_size)
>   
>   	debug("Invoking FPGA_CONFIG_START...\n");
>   
> +	flush_dcache_range((unsigned long)rbf_data, (unsigned long)(rbf_data + rbf_size));
> +
>   	ret = invoke_smc(INTEL_SIP_SMC_FPGA_CONFIG_START, &arg, 1, NULL, 0);
>   
>   	if (ret) {
> @@ -1023,6 +1028,8 @@ int intel_sdm_mb_load(Altera_desc *desc, const void *rbf_data, size_t rbf_size)
>   	u32 resp_len = 2;
>   	u32 resp_buf[2];
>   
> +	flush_dcache_range((unsigned long)rbf_data, (unsigned long)(rbf_data + rbf_size));
> +
>   	debug("Sending MBOX_RECONFIG...\n");
>   	ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_RECONFIG, MBOX_CMD_DIRECT, 0,
>   			    NULL, 0, &resp_len, resp_buf);

Applied.
M