Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c
index 6d240df..3cd2489 100644
--- a/drivers/hwtracing/intel_th/msu.c
+++ b/drivers/hwtracing/intel_th/msu.c
@@ -157,7 +157,8 @@
 	/* config */
 	unsigned int		enabled : 1,
 				wrap	: 1,
-				do_irq	: 1;
+				do_irq	: 1,
+				multi_is_broken : 1;
 	unsigned int		mode;
 	unsigned int		burst_len;
 	unsigned int		index;
@@ -718,9 +719,6 @@
 
 	if (old != expect) {
 		ret = -EINVAL;
-		dev_warn_ratelimited(msc_dev(win->msc),
-				     "expected lockout state %d, got %d\n",
-				     expect, old);
 		goto unlock;
 	}
 
@@ -741,6 +739,10 @@
 		/* from intel_th_msc_window_unlock(), don't warn if not locked */
 		if (expect == WIN_LOCKED && old == new)
 			return 0;
+
+		dev_warn_ratelimited(msc_dev(win->msc),
+				     "expected lockout state %d, got %d\n",
+				     expect, old);
 	}
 
 	return ret;
@@ -760,7 +762,7 @@
 	lockdep_assert_held(&msc->buf_mutex);
 
 	if (msc->mode > MSC_MODE_MULTI)
-		return -ENOTSUPP;
+		return -EINVAL;
 
 	if (msc->mode == MSC_MODE_MULTI) {
 		if (msc_win_set_lockout(msc->cur_win, WIN_READY, WIN_INUSE))
@@ -1294,7 +1296,7 @@
 	} else if (msc->mode == MSC_MODE_MULTI) {
 		ret = msc_buffer_multi_alloc(msc, nr_pages, nr_wins);
 	} else {
-		ret = -ENOTSUPP;
+		ret = -EINVAL;
 	}
 
 	if (!ret) {
@@ -1530,7 +1532,7 @@
 		if (ret >= 0)
 			*ppos = iter->offset;
 	} else {
-		ret = -ENOTSUPP;
+		ret = -EINVAL;
 	}
 
 put_count:
@@ -1664,7 +1666,7 @@
 {
 	atomic_set(&msc->user_count, -1);
 
-	msc->mode = MSC_MODE_MULTI;
+	msc->mode = msc->multi_is_broken ? MSC_MODE_SINGLE : MSC_MODE_MULTI;
 	mutex_init(&msc->buf_mutex);
 	INIT_LIST_HEAD(&msc->win_list);
 	INIT_LIST_HEAD(&msc->iter_list);
@@ -1676,10 +1678,13 @@
 	return 0;
 }
 
-static void msc_win_switch(struct msc *msc)
+static int msc_win_switch(struct msc *msc)
 {
 	struct msc_window *first;
 
+	if (list_empty(&msc->win_list))
+		return -EINVAL;
+
 	first = list_first_entry(&msc->win_list, struct msc_window, entry);
 
 	if (msc_is_last_win(msc->cur_win))
@@ -1691,6 +1696,8 @@
 	msc->base_addr = msc_win_base_dma(msc->cur_win);
 
 	intel_th_trace_switch(msc->thdev);
+
+	return 0;
 }
 
 /**
@@ -1871,6 +1878,9 @@
 	return -EINVAL;
 
 found:
+	if (i == MSC_MODE_MULTI && msc->multi_is_broken)
+		return -EOPNOTSUPP;
+
 	mutex_lock(&msc->buf_mutex);
 	ret = 0;
 
@@ -2025,16 +2035,15 @@
 	if (val != 1)
 		return -EINVAL;
 
+	ret = -EINVAL;
 	mutex_lock(&msc->buf_mutex);
 	/*
 	 * Window switch can only happen in the "multi" mode.
 	 * If a external buffer is engaged, they have the full
 	 * control over window switching.
 	 */
-	if (msc->mode != MSC_MODE_MULTI || msc->mbuf)
-		ret = -ENOTSUPP;
-	else
-		msc_win_switch(msc);
+	if (msc->mode == MSC_MODE_MULTI && !msc->mbuf)
+		ret = msc_win_switch(msc);
 	mutex_unlock(&msc->buf_mutex);
 
 	return ret ? ret : size;
@@ -2078,6 +2087,9 @@
 	if (!res)
 		msc->do_irq = 1;
 
+	if (INTEL_TH_CAP(to_intel_th(thdev), multi_is_broken))
+		msc->multi_is_broken = 1;
+
 	msc->index = thdev->id;
 
 	msc->thdev = thdev;