[PATCH] PCI: brcmstb: Restore initial fundamental reset

Phil Elwell phil at raspberrypi.com
Thu Nov 12 08:14:01 EST 2020

Commit 04356ac30771 ("PCI: brcmstb: Add bcm7278 PERST# support")
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.

Fixes: commit 04356ac30771 ("PCI: brcmstb: Add bcm7278 PERST# support")

Signed-off-by: Phil Elwell <phil at raspberrypi.com>
 drivers/pci/controller/pcie-brcmstb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index bea86899bd5d..a90d6f69c5a1 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -869,6 +869,8 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
 	/* 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 */

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