From a424d39cf5cce6122940842d2e6ff45b08e74ac7 Mon Sep 17 00:00:00 2001
From: Shuai Li <shuai.li@amlogic.com>
Date: Wed, 12 Jun 2019 16:13:45 +0800
Subject: [PATCH] audio: Fix audio stuck [1/1]

PD#SWPL-9142

Problem:
Audio stuck in stress test.

Solution:
Work around:
Wait until the fifo stops and then stop toddr.

Verify:
Tl1.

Change-Id: I8ce50732a7e23124b4b37374aa4505d79cd68cfe
Signed-off-by: Shuai Li <shuai.li@amlogic.com>
---
 sound/soc/amlogic/auge/ddr_mngr.c | 39 ++++++++++++++++++++++++++++---
 sound/soc/amlogic/auge/ddr_mngr.h |  4 ++++
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/sound/soc/amlogic/auge/ddr_mngr.c b/sound/soc/amlogic/auge/ddr_mngr.c
index 67c6cec21b0b..71480b0e3d55 100644
--- a/sound/soc/amlogic/auge/ddr_mngr.c
+++ b/sound/soc/amlogic/auge/ddr_mngr.c
@@ -446,6 +446,11 @@ unsigned int aml_toddr_get_status(struct toddr *to)
 	return aml_audiobus_read(actrl, reg);
 }
 
+unsigned int aml_toddr_get_fifo_cnt(struct toddr *to)
+{
+	return (aml_toddr_get_status(to) & TODDR_FIFO_CNT) >> 8;
+}
+
 void aml_toddr_ack_irq(struct toddr *to, int status)
 {
 	struct aml_audio_controller *actrl = to->actrl;
@@ -529,6 +534,31 @@ bool aml_toddr_burst_finished(struct toddr *to)
 	struct aml_audio_controller *actrl = to->actrl;
 	unsigned int reg_base = to->reg_base;
 	unsigned int reg;
+	bool fifo_stop = false;
+
+	/* This is a SW workaround.
+	 * If not wait until the fifo stops,
+	 * DDR will stuck and could not recover unless reboot.
+	 */
+	for (i = 0; i < 10; i++) {
+		unsigned int cnt0, cnt1, cnt2;
+
+		cnt0 = aml_toddr_get_fifo_cnt(to);
+		udelay(10);
+		cnt1 = aml_toddr_get_fifo_cnt(to);
+		udelay(10);
+		cnt2 = aml_toddr_get_fifo_cnt(to);
+		pr_debug("i: %d, fifo cnt:[%d] cnt1:[%d] cnt2:[%d]\n",
+			i, cnt0, cnt1, cnt2);
+
+		/* fifo stopped */
+		if ((cnt0 == cnt1) && (cnt0 == cnt2) && (cnt0 < (0x40 - 2))) {
+			pr_info("%s(), i (%d) cnt(%d) break out\n",
+				__func__, i, cnt2);
+			fifo_stop = true;
+			break;
+		}
+	}
 
 	/* max 200us delay */
 	for (i = 0; i < 200; i++) {
@@ -540,12 +570,15 @@ bool aml_toddr_burst_finished(struct toddr *to)
 		aml_audiobus_update_bits(actrl,	reg, 0xf << 8, 0x2 << 8);
 		addr_reply = aml_toddr_get_position(to);
 
-		if (addr_request == addr_reply)
+		if (addr_request == addr_reply) {
+			pr_info("%s(), fifo_stop %d\n", __func__, fifo_stop);
 			return true;
+		}
 
 		udelay(1);
-		pr_debug("delay:[%dus]; FRDDR_STATUS2: [0x%x] [0x%x]\n",
-			i, addr_request, addr_reply);
+		if ((i % 20) == 0)
+			pr_info("delay:[%dus]; FRDDR_STATUS2: [0x%x] [0x%x]\n",
+				i, addr_request, addr_reply);
 	}
 	pr_err("Error: 200us time out, TODDR_STATUS2: [0x%x] [0x%x]\n",
 				addr_request, addr_reply);
diff --git a/sound/soc/amlogic/auge/ddr_mngr.h b/sound/soc/amlogic/auge/ddr_mngr.h
index c3e9c7b263e1..5e0ddf5b3583 100644
--- a/sound/soc/amlogic/auge/ddr_mngr.h
+++ b/sound/soc/amlogic/auge/ddr_mngr.h
@@ -31,6 +31,9 @@
 #define MEMIF_INT_FIFO_DEPTH        BIT(5)
 #define MEMIF_INT_MASK              GENMASK(7, 0)
 
+#define TODDR_FIFO_CNT                    GENMASK(19, 8)
+#define FRDDR_FIFO_CNT                    GENMASK(17, 8)
+
 enum ddr_num {
 	DDR_A,
 	DDR_B,
@@ -252,6 +255,7 @@ void aml_toddr_force_finish(struct toddr *to);
 void aml_toddr_set_format(struct toddr *to, struct toddr_fmt *fmt);
 
 unsigned int aml_toddr_get_status(struct toddr *to);
+unsigned int aml_toddr_get_fifo_cnt(struct toddr *to);
 void aml_toddr_ack_irq(struct toddr *to, int status);
 
 void aml_toddr_insert_chanum(struct toddr *to);