disp: msm: sde: save register write logs in dump

Changes are made to add register write logs to memory dump.
This can be extracted from crash dumps and used for analysis.

Change-Id: If46aaa4ae68f83c79d4b51cbe5dfd22340aa991d
Signed-off-by: Yashwanth <yvulapu@codeaurora.org>

msm/sde_dbg_evtlog.c

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2016-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2016-2021, The Linux Foundation. All rights reserved.
  */
 
 #define pr_fmt(fmt)	"sde_dbg:[%s] " fmt, __func__
@@ -101,6 +101,31 @@ exit:
 	spin_unlock_irqrestore(&evtlog->spin_lock, flags);
 }
 
+void sde_reglog_log(u8 blk_id, u32 val, u32 addr)
+{
+	unsigned long flags;
+	struct sde_dbg_reglog_log *log;
+	struct sde_dbg_reglog *reglog = sde_dbg_base_reglog;
+
+	if (!reglog)
+		return;
+
+	spin_lock_irqsave(&reglog->spin_lock, flags);
+
+	log = &reglog->logs[reglog->curr];
+
+	log->blk_id = blk_id;
+	log->val = val;
+	log->addr = addr;
+	log->time = local_clock();
+	log->pid = current->pid;
+
+	reglog->curr = (reglog->curr + 1) % SDE_REGLOG_ENTRY;
+	reglog->last++;
+
+	spin_unlock_irqrestore(&reglog->spin_lock, flags);
+}
+
 /* always dump the last entries which are not dumped yet */
 static bool _sde_evtlog_dump_calc_range(struct sde_dbg_evtlog *evtlog,
 		bool update_last_entry, bool full_dump)
@@ -211,6 +236,19 @@ struct sde_dbg_evtlog *sde_evtlog_init(void)
 	return evtlog;
 }
 
+struct sde_dbg_reglog *sde_reglog_init(void)
+{
+	struct sde_dbg_reglog *reglog;
+
+	reglog = kzalloc(sizeof(*reglog), GFP_KERNEL);
+	if (!reglog)
+		return ERR_PTR(-ENOMEM);
+
+	spin_lock_init(&reglog->spin_lock);
+
+	return reglog;
+}
+
 int sde_evtlog_get_filter(struct sde_dbg_evtlog *evtlog, int index,
 		char *buf, size_t bufsz)
 {
@@ -312,3 +350,11 @@ void sde_evtlog_destroy(struct sde_dbg_evtlog *evtlog)
 	}
 	kfree(evtlog);
 }
+
+void sde_reglog_destroy(struct sde_dbg_reglog *reglog)
+{
+	if (!reglog)
+		return;
+
+	kfree(reglog);
+}