[PATCH 2/2] firmware: arm_scmi: Support 'reg-io-width' property for shared memory
Peng Fan
peng.fan at nxp.com
Sun Aug 11 05:42:05 PDT 2024
> Subject: [PATCH 2/2] firmware: arm_scmi: Support 'reg-io-width'
> property for shared memory
>
> Some shared memory areas might only support a certain access width,
> (e.g.: 32 bits accesses only). Update the shmem layer to support
> reading from and writing to such shared memory area using the
> specified I/O width in the Device Tree. The various transport layers
> making use of the shmem.c code are updated accordingly to pass the
> I/O width to the routines that need it.
>
> Signed-off-by: Florian Fainelli <florian.fainelli at broadcom.com>
> ---
[...]
> }
>
> static void smc_mark_txdone(struct scmi_chan_info *cinfo, int ret, diff
> --git a/drivers/firmware/arm_scmi/shmem.c
> b/drivers/firmware/arm_scmi/shmem.c
> index 01d8a9398fe8..192262d63baa 100644
> --- a/drivers/firmware/arm_scmi/shmem.c
> +++ b/drivers/firmware/arm_scmi/shmem.c
> @@ -34,9 +34,20 @@ struct scmi_shared_mem {
> u8 msg_payload[];
> };
>
> +#define __shmem_copy_toio_tpl(s) \
> + for (unsigned int i = 0; i < xfer->tx.len; i += shmem_io_width)
> \
> + iowrite##s(((u##s *)(xfer->tx.buf))[i / shmem_io_width],
> \
> + shmem->msg_payload + i);
there will be a barrier with iowrite, use raw_write##s?
> +
> +#define __shmem_copy_fromio_tpl(s) \
> + for (unsigned int i = 0; i < xfer->rx.len; i += shmem_io_width)
> \
> + ((u##s *)(xfer->rx.buf))[i / shmem_io_width] =
> \
> + ioread##s(shmem->msg_payload +
> shmem_io_width + i);
Use raw_ioread##s?
Regards,
Peng.
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