| Message ID | 20230111134513.2495510-8-conor.dooley@microchip.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Conor Dooley |
| Headers | show |
| Series | MPFS system controller/mailbox fixes | expand |
| Context | Check | Description |
|---|---|---|
| conchuod/patch_count | success | Link |
| conchuod/cover_letter | success | Series has a cover letter |
| conchuod/tree_selection | success | Guessed tree name to be fixes |
| conchuod/fixes_present | success | Fixes tag present in non-next series |
| conchuod/maintainers_pattern | success | MAINTAINERS pattern errors before the patch: 13 and now 13 |
| conchuod/verify_signedoff | success | Signed-off-by tag matches author and committer |
| conchuod/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| conchuod/module_param | success | Was 0 now: 0 |
| conchuod/alphanumeric_selects | success | Out of order selects before the patch: 57 and now 57 |
| conchuod/build_rv32_defconfig | success | Build OK |
| conchuod/build_warn_rv64 | success | Errors and warnings before: 2054 this patch: 2054 |
| conchuod/dtb_warn_rv64 | success | Errors and warnings before: 4 this patch: 4 |
| conchuod/header_inline | success | No static functions without inline keyword in header files |
| conchuod/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 35 lines checked |
| conchuod/source_inline | success | Was 0 now: 0 |
| conchuod/build_rv64_nommu_k210_defconfig | success | Build OK |
| conchuod/verify_fixes | success | No Fixes tag |
| conchuod/build_rv64_nommu_virt_defconfig | success | Build OK |
diff --git a/drivers/soc/microchip/mpfs-sys-controller.c b/drivers/soc/microchip/mpfs-sys-controller.c index 4aadd05769d2..75422db75fe5 100644 --- a/drivers/soc/microchip/mpfs-sys-controller.c +++ b/drivers/soc/microchip/mpfs-sys-controller.c @@ -41,14 +41,25 @@ int mpfs_blocking_transaction(struct mpfs_sys_controller *sys_controller, struct reinit_completion(&sys_controller->c); ret = mbox_send_message(sys_controller->chan, msg); - if (ret < 0) + if (ret < 0) { + dev_warn(sys_controller->client.dev, + "MPFS sys controller service timeout\n"); goto out; + } ret = 0; /* mbox_send_message returns postitive integers on success */ + + /* + * Unfortunately, the system controller will only deliver an interrupt + * if a service succeeds. mbox_send_message() will block until the busy + * flag is gone. If the busy flag is gone but no interrupt has arrived + * to trigger the rx callback then the service can be deemed to have + * failed. + */ if (!wait_for_completion_timeout(&sys_controller->c, timeout)) { - ret = -ETIMEDOUT; + ret = -EBADMSG; dev_warn(sys_controller->client.dev, - "MPFS sys controller transaction timeout\n"); + "MPFS sys controller service failed\n"); } out: @@ -106,6 +117,7 @@ static int mpfs_sys_controller_probe(struct platform_device *pdev) sys_controller->client.dev = dev; sys_controller->client.rx_callback = rx_callback; sys_controller->client.tx_block = 1U; + sys_controller->client.tx_tout = msecs_to_jiffies(MPFS_SYS_CTRL_TIMEOUT_MS); sys_controller->chan = mbox_request_channel(&sys_controller->client, 0); if (IS_ERR(sys_controller->chan)) {
The system controller will only deliver an interrupt if a service succeeds. This leaves us in the unfortunate position with current code where there is no way to differentiate between a legitimate timeout where the service has not completed & where it has completed, but failed. mbox_send_message() has its own completion, and it will time out of the system controller does not lower the busy flag. In this case, a timeout has occurred and the error can be propagated back to the caller. If the busy flag is lowered, but no interrupt has arrived to trigger the rx callback, the service can be deemed to have failed. Report EBADMSG in this case so that callers can differentiate. Signed-off-by: Conor Dooley <conor.dooley@microchip.com> --- drivers/soc/microchip/mpfs-sys-controller.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)