On 8/10/2024 2:46 PM, Florian Fainelli wrote:
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>
Doing a self review, though I will only resend after collecting
additional feedback.
---
drivers/firmware/arm_scmi/common.h | 14 +++-
.../arm_scmi/scmi_transport_mailbox.c | 12 ++-
.../firmware/arm_scmi/scmi_transport_optee.c | 7 +-
.../firmware/arm_scmi/scmi_transport_smc.c | 10 ++-
drivers/firmware/arm_scmi/shmem.c | 77 ++++++++++++++++---
5 files changed, 96 insertions(+), 24 deletions(-)
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 69928bbd01c2..97dae844a190 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -170,6 +170,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id);
* This can be dynamically set by transports at run-time
* inside their provided .chan_setup().
* @transport_info: Transport layer related information
+ * @shmem_io_width: I/O width in bytes of the shared memory area
*/
struct scmi_chan_info {
int id;
@@ -178,6 +179,7 @@ struct scmi_chan_info {
struct scmi_handle *handle;
bool no_completion_irq;
void *transport_info;
+ u32 shmem_io_width;
This is not used because the individual transports store the
shmem_io_width in their own transport_info structure.
[snip]
+#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);
+
+#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);
This needs to be shmem->msg_payload + 4 + i. This worked in my testing
because I was precisely tseting with 'reg-io-width = <4>'.
[snip]
static u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem)
@@ -81,8 +109,34 @@ static u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem)
return ioread32(&shmem->msg_header);
}
+static void __shmem_fetch_resp_notif_data(struct scmi_xfer *xfer,
+ struct scmi_shared_mem __iomem *shmem,
+ u32 shmem_io_width)
+{
+ /* Take a copy to the rx buffer.. */
+ switch (shmem_io_width) {
+ case 1:
+ __shmem_copy_fromio_tpl(8);
+ break;
+ case 2:
+ __shmem_copy_fromio_tpl(16);
+ break;
+ case 4:
+ __shmem_copy_fromio_tpl(32);
+ break;
+ case 8:
+ __shmem_copy_fromio_tpl(32);
This should be 64 and it looks like ioread64/iowrite64 is not
necessarily defined for 32-bit configurations, so this needs to be gated
with a CONFIG_64BIT define here since ioread64/iowrite64 in
include/asm-generic/io.h is defined that way.
--
Florian
