[PATCH] arm: rpi: perform XHCI firmware upload only once

[Marek Szyprowski]

XHCI firmware upload must be performed only once after initializing the
PCI bridge. This fixes USB stack initialization after calling "usb stop;
usb start" on Raspberry Pi 4B.

Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
 arch/arm/mach-bcm283x/msg.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/mach-bcm283x/msg.c b/arch/arm/mach-bcm283x/msg.c
index 347aece3cd..345f7fe2b7 100644
--- a/arch/arm/mach-bcm283x/msg.c
+++ b/arch/arm/mach-bcm283x/msg.c
@@ -170,6 +170,12 @@ int bcm2711_notify_vl805_reset(void)
 	ALLOC_CACHE_ALIGN_BUFFER(struct msg_notify_vl805_reset,
 				 msg_notify_vl805_reset, 1);
 	int ret;
+	static int done = false;
+
+	if (done)
+		return 0;
+
+	done = true;
 
 	BCM2835_MBOX_INIT_HDR(msg_notify_vl805_reset);
 	BCM2835_MBOX_INIT_TAG(&msg_notify_vl805_reset->dev_addr,
-- 
2.17.1