PCI: brcmstb: Wait for Raspberry Pi's firmware when present

xHCI's PCI fixup, run at the end of pcie-brcmstb's probe, depends on
RPi4's VideoCore firmware interface to be up and running. It's possible
for both initializations to race, so make sure it's available prior to
starting.

Link: https://lore.kernel.org/r/20200505161318.26200-4-nsaenzjulienne@suse.de
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
This commit is contained in:
Nicolas Saenz Julienne 2020-05-05 18:13:16 +02:00 committed by Lorenzo Pieralisi
parent fbbc5ff3f7
commit 44331189f9

View File

@ -28,6 +28,8 @@
#include <linux/string.h>
#include <linux/types.h>
#include <soc/bcm2835/raspberrypi-firmware.h>
#include "../pci.h"
/* BRCM_PCIE_CAP_REGS - Offset for the mandatory capability config regs */
@ -929,11 +931,26 @@ static int brcm_pcie_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node, *msi_np;
struct pci_host_bridge *bridge;
struct device_node *fw_np;
struct brcm_pcie *pcie;
struct pci_bus *child;
struct resource *res;
int ret;
/*
* We have to wait for Raspberry Pi's firmware interface to be up as a
* PCI fixup, rpi_firmware_init_vl805(), depends on it. This driver's
* probe can race with the firmware interface's (see
* drivers/firmware/raspberrypi.c) and potentially break the PCI fixup.
*/
fw_np = of_find_compatible_node(NULL, NULL,
"raspberrypi,bcm2835-firmware");
if (fw_np && !rpi_firmware_get(fw_np)) {
of_node_put(fw_np);
return -EPROBE_DEFER;
}
of_node_put(fw_np);
bridge = devm_pci_alloc_host_bridge(&pdev->dev, sizeof(*pcie));
if (!bridge)
return -ENOMEM;