From e819152f96f67e20f1d7a00446cd9c0035850825 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Wed, 11 Nov 2020 17:08:33 +0000 Subject: [PATCH] PCI: brcmstb: Restore initial fundamental reset [1] replaced a single reset function with a pointer to one of two implementations, but also removed the call asserting the reset at the start of brcm_pcie_setup. Doing so breaks Raspberry Pis with VL805 XHCI controllers lacking dedicated SPI EEPROMs, which have been used for USB booting but then need to be reset so that the kernel can reconfigure them. The lack of a reset causes the firmware's loading of the EEPROM image to RAM to fail, breaking USB for the kernel. See: https://www.raspberrypi.org/forums/viewtopic.php?p=1758157#p1758157 Fixes: 04356ac30771 ("PCI: brcmstb: Add bcm7278 PERST# support") [1] 04356ac30771 ("PCI: brcmstb: Add bcm7278 PERST# support") Signed-off-by: Phil Elwell --- drivers/pci/controller/pcie-brcmstb.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -879,6 +879,8 @@ static int brcm_pcie_setup(struct brcm_p /* Reset the bridge */ pcie->bridge_sw_init_set(pcie, 1); + pcie->perst_set(pcie, 1); + usleep_range(100, 200); /* Take the bridge out of reset */