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/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 9a5464c..ec6f28e 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -69,7 +69,7 @@
 static bool arch_timer_c3stop;
 static bool arch_timer_mem_use_virtual;
 static bool arch_counter_suspend_stop;
-static bool vdso_default = true;
+static enum vdso_arch_clockmode vdso_default = VDSO_CLOCKMODE_ARCHTIMER;
 
 static cpumask_t evtstrm_available = CPU_MASK_NONE;
 static bool evtstrm_enable = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM);
@@ -348,7 +348,7 @@
 	do {								\
 		_val = read_sysreg(reg);				\
 		_retries--;						\
-	} while (((_val + 1) & GENMASK(9, 0)) <= 1 && _retries);	\
+	} while (((_val + 1) & GENMASK(8, 0)) <= 1 && _retries);	\
 									\
 	WARN_ON_ONCE(!_retries);					\
 	_val;								\
@@ -392,10 +392,10 @@
 	ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
 
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
-		cval = evt + arch_counter_get_cntpct();
+		cval = evt + arch_counter_get_cntpct_stable();
 		write_sysreg(cval, cntp_cval_el0);
 	} else {
-		cval = evt + arch_counter_get_cntvct();
+		cval = evt + arch_counter_get_cntvct_stable();
 		write_sysreg(cval, cntv_cval_el0);
 	}
 
@@ -476,6 +476,14 @@
 		.set_next_event_virt = erratum_set_next_event_tval_virt,
 	},
 #endif
+#ifdef CONFIG_ARM64_ERRATUM_1418040
+	{
+		.match_type = ate_match_local_cap_id,
+		.id = (void *)ARM64_WORKAROUND_1418040,
+		.desc = "ARM erratum 1418040",
+		.disable_compat_vdso = true,
+	},
+#endif
 };
 
 typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *,
@@ -560,8 +568,11 @@
 	 * change both the default value and the vdso itself.
 	 */
 	if (wa->read_cntvct_el0) {
-		clocksource_counter.archdata.vdso_direct = false;
-		vdso_default = false;
+		clocksource_counter.archdata.clock_mode = VDSO_CLOCKMODE_NONE;
+		vdso_default = VDSO_CLOCKMODE_NONE;
+	} else if (wa->disable_compat_vdso && vdso_default != VDSO_CLOCKMODE_NONE) {
+		vdso_default = VDSO_CLOCKMODE_ARCHTIMER_NOCOMPAT;
+		clocksource_counter.archdata.clock_mode = vdso_default;
 	}
 }
 
@@ -807,15 +818,24 @@
 
 static void arch_timer_configure_evtstream(void)
 {
-	int evt_stream_div, pos;
+	int evt_stream_div, lsb;
 
-	/* Find the closest power of two to the divisor */
-	evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ;
-	pos = fls(evt_stream_div);
-	if (pos > 1 && !(evt_stream_div & (1 << (pos - 2))))
-		pos--;
+	/*
+	 * As the event stream can at most be generated at half the frequency
+	 * of the counter, use half the frequency when computing the divider.
+	 */
+	evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ / 2;
+
+	/*
+	 * Find the closest power of two to the divisor. If the adjacent bit
+	 * of lsb (last set bit, starts from 0) is set, then we use (lsb + 1).
+	 */
+	lsb = fls(evt_stream_div) - 1;
+	if (lsb > 0 && (evt_stream_div & BIT(lsb - 1)))
+		lsb++;
+
 	/* enable event stream */
-	arch_timer_evtstrm_enable(min(pos, 15));
+	arch_timer_evtstrm_enable(max(0, min(lsb, 15)));
 }
 
 static void arch_counter_set_user_access(void)
@@ -979,7 +999,7 @@
 		}
 
 		arch_timer_read_counter = rd;
-		clocksource_counter.archdata.vdso_direct = vdso_default;
+		clocksource_counter.archdata.clock_mode = vdso_default;
 	} else {
 		arch_timer_read_counter = arch_counter_get_cntvct_mem;
 	}