From a11d752b04ba4fa8aa47d3de40ba46904698dcbc Mon Sep 17 00:00:00 2001
From: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Date: Wed, 11 Aug 2021 20:37:11 -0700
Subject: [PATCH] drivers: Intel: IDC: make core power down IDC blocking

make the core power down IDC blocking to ensure the core is
actually idle before notifying the host.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
---
 src/arch/xtensa/lib/cpu.c     |  2 +-
 src/drivers/intel/cavs/idc.c  | 18 ++++++++++++++++++
 src/include/sof/drivers/idc.h |  3 +++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/arch/xtensa/lib/cpu.c b/src/arch/xtensa/lib/cpu.c
index 8e90b085822c..dcbe811f2476 100644
--- a/src/arch/xtensa/lib/cpu.c
+++ b/src/arch/xtensa/lib/cpu.c
@@ -113,7 +113,7 @@ void arch_cpu_disable_core(int id)
 		IDC_MSG_POWER_DOWN, IDC_MSG_POWER_DOWN_EXT, id };
 
 	if (arch_cpu_is_core_enabled(id)) {
-		idc_send_msg(&power_down, IDC_NON_BLOCKING);
+		idc_send_msg(&power_down, IDC_POWER_DOWN);
 
 		active_cores_mask ^= (1 << id);
 #if CONFIG_NO_SECONDARY_CORE_ROM
diff --git a/src/drivers/intel/cavs/idc.c b/src/drivers/intel/cavs/idc.c
index 2eb4d682aa49..e34535d7b776 100644
--- a/src/drivers/intel/cavs/idc.c
+++ b/src/drivers/intel/cavs/idc.c
@@ -95,6 +95,16 @@ static bool idc_is_powered_up(int target_core)
 		TRACE_BOOT_PLATFORM;
 }
 
+/**
+ * \brief Checks core status register.
+ * \param[in] target_core Id of the core powering up.
+ * \return True if core powered up, false otherwise.
+ */
+static bool idc_is_powered_down(int target_core)
+{
+	return mailbox_sw_reg_read(PLATFORM_TRACEP_SECONDARY_CORE(target_core)) == 0;
+}
+
 /**
  * \brief Sends IDC message.
  * \param[in,out] msg Pointer to IDC message.
@@ -150,6 +160,14 @@ int idc_send_msg(struct idc_msg *msg, uint32_t mode)
 			       mailbox_sw_reg_read(PLATFORM_TRACEP_SECONDARY_CORE(msg->core)));
 		}
 		break;
+	case IDC_POWER_DOWN:
+		ret = idc_wait_in_blocking_mode(msg->core, idc_is_powered_down);
+		if (ret < 0) {
+			tr_err(&idc_tr, "idc_send_msg(), power down core %d failed, reason 0x%x",
+			       msg->core,
+			       mailbox_sw_reg_read(PLATFORM_TRACEP_SECONDARY_CORE(msg->core)));
+		}
+		break;
 	}
 
 	return ret;
diff --git a/src/include/sof/drivers/idc.h b/src/include/sof/drivers/idc.h
index a433cd39461b..2074a7049808 100644
--- a/src/include/sof/drivers/idc.h
+++ b/src/include/sof/drivers/idc.h
@@ -30,6 +30,9 @@
 /** \brief IDC send core power up flag. */
 #define IDC_POWER_UP		2
 
+/** \brief IDC send core power down flag. */
+#define IDC_POWER_DOWN		3
+
 /** \brief IDC send timeout in microseconds. */
 #define IDC_TIMEOUT	10000