On Mon, 02 May 2022 10:38:31 +0100, Hector Martin marcan@marcan.st wrote:
If we're probing the PCI controller and some GPIOs are not available and cause a probe defer, we can end up leaving some ports initialized and not others and making a mess.
Check for PERST# GPIOs for all ports first, and just return -EPROBE_DEFER if any are not ready yet, without bringing anything up.
Fixes: 1e33888fbe44 ("PCI: apple: Add initial hardware bring-up") Cc: stable@vger.kernel.org Signed-off-by: Hector Martin marcan@marcan.st
drivers/pci/controller/pcie-apple.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)
diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c index e0c06c0ee731..e3aa2d461739 100644 --- a/drivers/pci/controller/pcie-apple.c +++ b/drivers/pci/controller/pcie-apple.c @@ -507,6 +507,20 @@ static u32 apple_pcie_rid2sid_write(struct apple_pcie_port *port, return readl_relaxed(port->base + PORT_RID2SID(idx)); } +static int apple_pcie_probe_port(struct device_node *np) +{
- struct gpio_desc *gd;
- gd = gpiod_get_from_of_node(np, "reset-gpios", 0,
GPIOD_OUT_LOW, "PERST#");- if (IS_ERR(gd)) {
return PTR_ERR(gd);- }
- gpiod_put(gd);
- return 0;
+}
static int apple_pcie_setup_port(struct apple_pcie *pcie, struct device_node *np) { @@ -797,8 +811,18 @@ static int apple_pcie_init(struct pci_config_window *cfg) static int apple_pcie_probe(struct platform_device *pdev) {
- struct device *dev = &pdev->dev;
- struct device_node *of_port; int ret;
- /* Check for probe dependencies for all ports first */
- for_each_child_of_node(dev->of_node, of_port) {
ret = apple_pcie_probe_port(of_port);of_node_put(of_port);if (ret)return dev_err_probe(dev, ret, "Port %pOF probe fail\n", of_port);- }
- ret = bus_register_notifier(&pci_bus_type, &apple_pcie_nb); if (ret) return ret;
Acked-by: Marc Zyngier maz@kernel.org
M.