On 8/11/2024 5:42 AM, Peng Fan wrote:
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@xxxxxxxxxxxx>
---
[...]
}
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?
Makes sense, and that matches what memcpy_{from,to}_io() does, too.
+
+#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?
Agreed.
--
Florian
