disp: msm: add devcoredump support for sde_dbg

Add devcoredump support for sde_dbg. Devcoredump is a mechanism
providing generalized way to get data from kernel modules. This change
integrates devcoredump into sde_dbg to get evtlog, register dump and
dbg_bus when display failure happens.

Change-Id: I4daf25443ccd2646de580314a0bfe08b84dbc282
Signed-off-by: Bruce Hoo <quic_bingchua@quicinc.com>

msm/sde_dbg.h

@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
+ * Copyright (c) 2021 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2016-2021, The Linux Foundation. All rights reserved.
  */
 
@@ -10,6 +11,7 @@
 #include <linux/debugfs.h>
 #include <linux/list.h>
 #include <soc/qcom/minidump.h>
+#include <drm/drm_print.h>
 
 /* select an uncommon hex value for the limiter */
 #define SDE_EVTLOG_DATA_LIMITER	(0xC0DEBEEF)
@@ -65,6 +67,7 @@ enum sde_dbg_dump_flag {
 	SDE_DBG_DUMP_IN_LOG = BIT(0),
 	SDE_DBG_DUMP_IN_MEM = BIT(1),
 	SDE_DBG_DUMP_IN_LOG_LIMITED = BIT(2),
+	SDE_DBG_DUMP_IN_COREDUMP = BIT(3),
 };
 
 enum sde_dbg_dump_context {
@@ -73,8 +76,13 @@ enum sde_dbg_dump_context {
 	SDE_DBG_DUMP_CLK_ENABLED_CTX,
 };
 
-/* default dump mode for eventlogs, reg-dump & debugbus-dump */
-#define SDE_DBG_DEFAULT_DUMP_MODE	SDE_DBG_DUMP_IN_MEM
+/*
+ * Set in_coredump as default mode. Any existing script which rely on
+ * dump_mode to be in_mem should now explicitly run the cmd
+ * "adb shell echo 2 > /sys/kernel/debug/dri/0/debug/reg_dump" before
+ * doing the test cases.
+ */
+#define SDE_DBG_DEFAULT_DUMP_MODE	SDE_DBG_DUMP_IN_COREDUMP
 
 /*
  * Define blocks for register write logging.
@@ -158,6 +166,8 @@ struct sde_dbg_evtlog {
 	u32 next;
 	u32 enable;
 	u32 dump_mode;
+	char *dumped_evtlog;
+	u32 log_size;
 	spinlock_t spin_lock;
 	struct list_head filter_list;
 };
@@ -338,11 +348,24 @@ void sde_evtlog_log(struct sde_dbg_evtlog *evtlog, const char *name, int line,
 void sde_reglog_log(u8 blk_id, u32 val, u32 addr);
 
 /**
- * sde_evtlog_dump_all - print all entries in event log to kernel log
+ * sde_evtlog_dump_to_buffer - parse one line of evtlog to a given buffer
  * @evtlog:	pointer to evtlog
- * Returns:	none
+ * @evtlog_buf: buffer to store evtlog
+ * @evtlog_buf_size: lenght of the buffer
+ * @update_last_entry: whether update last dump marker
+ * @full_dump: 1, print the whole evtlog captured; 0, print last 256 lines of log
+ * Returns:	log size
  */
-void sde_evtlog_dump_all(struct sde_dbg_evtlog *evtlog);
+ssize_t sde_evtlog_dump_to_buffer(struct sde_dbg_evtlog *evtlog,
+		char *evtlog_buf, ssize_t evtlog_buf_size,
+		bool update_last_entry, bool full_dump);
+
+/**
+ * sde_evtlog_count - count the current log size for print
+ * @evtlog:	pointer to evtlog
+ * Returns:	log size
+ */
+u32 sde_evtlog_count(struct sde_dbg_evtlog *evtlog);
 
 /**
  * sde_evtlog_is_enabled - check whether log collection is enabled for given