/*
* Microchip PolarFire SoC (MPFS) system controller/mailbox controller driver
*
- * Copyright (c) 2020 Microchip Corporation. All rights reserved.
+ * Copyright (c) 2020-2022 Microchip Corporation. All rights reserved.
*
* Author: Conor Dooley <conor.dooley@microchip.com>
*
#define SCB_STATUS_NOTIFY_MASK BIT(SCB_STATUS_NOTIFY)
#define SCB_STATUS_POS (16)
-#define SCB_STATUS_MASK GENMASK_ULL(SCB_STATUS_POS + SCB_MASK_WIDTH, SCB_STATUS_POS)
+#define SCB_STATUS_MASK GENMASK(SCB_STATUS_POS + SCB_MASK_WIDTH - 1, SCB_STATUS_POS)
struct mpfs_mbox {
struct mbox_controller controller;
struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv;
struct mpfs_mss_response *response = mbox->response;
u16 num_words = ALIGN((response->resp_size), (4)) / 4U;
- u32 i;
+ u32 i, status;
if (!response->resp_msg) {
dev_err(mbox->dev, "failed to assign memory for response %d\n", -ENOMEM);
return;
}
+ /*
+ * The status is stored in bits 31:16 of the SERVICES_SR register.
+ * It is only valid when BUSY == 0.
+ * We should *never* get an interrupt while the controller is
+ * still in the busy state. If we do, something has gone badly
+ * wrong & the content of the mailbox would not be valid.
+ */
+ if (mpfs_mbox_busy(mbox)) {
+ dev_err(mbox->dev, "got an interrupt but system controller is busy\n");
+ response->resp_status = 0xDEAD;
+ return;
+ }
+
+ status = readl_relaxed(mbox->ctrl_base + SERVICES_SR_OFFSET);
+
+ /*
+ * If the status of the individual servers is non-zero, the service has
+ * failed. The contents of the mailbox at this point are not be valid,
+ * so don't bother reading them. Set the status so that the driver
+ * implementing the service can handle the result.
+ */
+ response->resp_status = (status & SCB_STATUS_MASK) >> SCB_STATUS_POS;
+ if (response->resp_status)
+ return;
+
if (!mpfs_mbox_busy(mbox)) {
for (i = 0; i < num_words; i++) {
response->resp_msg[i] =