Tegra186: mce: max retries for ARI requests
This patch adds max retries for all ARI requests and asserts
if the ARI request is still busy.
Change-Id: I454ad9b557bb59e513e4c0c6f071275c87d0e07a
Signed-off-by: Steven Kao <skao@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/soc/t186/drivers/mce/ari.c b/plat/nvidia/tegra/soc/t186/drivers/mce/ari.c
index 7f711a7..87fadbe 100644
--- a/plat/nvidia/tegra/soc/t186/drivers/mce/ari.c
+++ b/plat/nvidia/tegra/soc/t186/drivers/mce/ari.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -30,10 +30,13 @@
#include <arch.h>
#include <arch_helpers.h>
+#include <assert.h>
#include <debug.h>
+#include <delay_timer.h>
#include <denver.h>
#include <mmio.h>
#include <mce_private.h>
+#include <platform.h>
#include <sys/errno.h>
#include <t18x_ari.h>
@@ -49,10 +52,13 @@
#define ARI_RESPONSE_DATA_HI 0x18
/* Status values for the current request */
-#define ARI_REQ_PENDING 1
-#define ARI_REQ_ONGOING 3
-#define ARI_REQUEST_VALID_BIT (1 << 8)
-#define ARI_EVT_MASK_STANDBYWFI_BIT (1 << 7)
+#define ARI_REQ_PENDING 1U
+#define ARI_REQ_ONGOING 3U
+#define ARI_REQUEST_VALID_BIT (1U << 8)
+#define ARI_EVT_MASK_STANDBYWFI_BIT (1U << 7)
+
+/* default timeout (ms) to wait for ARI completion */
+#define ARI_MAX_RETRY_COUNT 2000
/*******************************************************************************
* ARI helper functions
@@ -96,7 +102,8 @@
static int ari_request_wait(uint32_t ari_base, uint32_t evt_mask, uint32_t req,
uint32_t lo, uint32_t hi)
{
- int status;
+ uint32_t retries = ARI_MAX_RETRY_COUNT;
+ uint32_t status;
/* program the request, event_mask, hi and lo registers */
ari_write_32(ari_base, lo, ARI_REQUEST_DATA_LO);
@@ -112,10 +119,36 @@
if (evt_mask)
return 0;
- /* NOTE: add timeout check if needed */
- status = ari_read_32(ari_base, ARI_STATUS);
- while (status & (ARI_REQ_ONGOING | ARI_REQ_PENDING))
+ /* For shutdown/reboot commands, we dont have to check for timeouts */
+ if ((req == (uint32_t)TEGRA_ARI_MISC_CCPLEX) &&
+ ((lo == (uint32_t)TEGRA_ARI_MISC_CCPLEX_SHUTDOWN_POWER_OFF) ||
+ (lo == (uint32_t)TEGRA_ARI_MISC_CCPLEX_SHUTDOWN_REBOOT))) {
+ return 0;
+ }
+
+ /*
+ * Wait for the command response for not more than the timeout
+ */
+ while (retries != 0U) {
+
+ /* read the command status */
status = ari_read_32(ari_base, ARI_STATUS);
+ if ((status & (ARI_REQ_ONGOING | ARI_REQ_PENDING)) == 0U)
+ break;
+
+ /* delay 1 ms */
+ mdelay(1);
+
+ /* decrement the retry count */
+ retries--;
+ }
+
+ /* assert if the command timed out */
+ if (retries == 0U) {
+ ERROR("ARI request timed out: req %d on CPU %d\n",
+ req, plat_my_core_pos());
+ assert(retries != 0U);
+ }
return 0;
}
