usb: host: xhci-rcar: Don't reload firmware after the completion

stable inclusion
from stable-5.10.64
commit d544c9a2190a4beff995be6a74a750dd5a8d7676
bugzilla: 182256 https://gitee.com/openeuler/kernel/issues/I4EG0U

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d544c9a2190a4beff995be6a74a750dd5a8d7676

--------------------------------

commit 57f3ffdc upstream.

According to the datasheet, "Upon the completion of FW Download,
there is no need to write or reload FW.". Otherwise, it's possible
to cause unexpected behaviors. So, adds such a condition.

Fixes: 4ac8918f ("usb: host: xhci-plat: add support for the R-Car H2 and M2 xHCI controllers")
Cc: stable@vger.kernel.org # v3.17+
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210827063227.81990-1-yoshihiro.shimoda.uh@renesas.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/usb/host/xhci-rcar.c

@@ -134,6 +134,13 @@ static int xhci_rcar_download_firmware(struct usb_hcd *hcd)
 	const struct soc_device_attribute *attr;
 	const char *firmware_name;
 
+	/*
+	 * According to the datasheet, "Upon the completion of FW Download,
+	 * there is no need to write or reload FW".
+	 */
+	if (readl(regs + RCAR_USB3_DL_CTRL) & RCAR_USB3_DL_CTRL_FW_SUCCESS)
+		return 0;
+
 	attr = soc_device_match(rcar_quirks_match);
 	if (attr)
 		quirks = (uintptr_t)attr->data;