Change in coreboot[master]: device: Wait for PCI devices to show up

[Felix Singer (Code Review)]

Hello Nico Huber,

I'd like you to do a code review. Please visit

https://review.coreboot.org/c/coreboot/+/39842

to review the following change.

Change subject: device: Wait for PCI devices to show up
......................................................................

device: Wait for PCI devices to show up

Some PCI devices need too long to show up. If a device is explicitly
mentioned as `on` in the devicetree, give it 1s.

Change-Id: Id8659bc38e0c7e3ec065beb0b1a303fe1e2665d2
Signed-off-by: Nico Huber 
---
M src/device/pci_device.c
1 file changed, 22 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/42/39842/1

diff --git a/src/device/pci_device.c b/src/device/pci_device.c
index b1e88a6..5ee7b39 100644
--- a/src/device/pci_device.c
+++ b/src/device/pci_device.c
@@ -33,10 +33,10 @@
 #include <device/hypertransport.h>
 #include <pc80/i8259.h>
 #include <security/vboot/vbnv.h>
+#include <timer.h>
 #include <timestamp.h>
 #include <types.h>

-
 u8 pci_moving_config8(struct device *dev, unsigned int reg)
 {
    u8 value, ones, zeroes;
@@ -1095,6 +1095,27 @@
    	id = pci_read_config32(dev, PCI_VENDOR_ID);

/*
+		 * If the device is enabled in the devicetree,
+		 * wait a little for it to show up.
+		 */
+		if (dev->enabled && id == 0xffffffff) {
+			static struct stopwatch pci_reset_sw;
+
+			if (pci_reset_sw.start.microseconds ==
+			    pci_reset_sw.expires.microseconds)
+				stopwatch_init_msecs_expire(&pci_reset_sw, 1000);
+
+			while (id == 0xffffffff && !stopwatch_expired(&pci_reset_sw)) {
+				mdelay(10);
+				id = pci_read_config32(dev, PCI_VENDOR_ID);
+			}
+
+			if (id != 0xffffffff)
+				printk(BIOS_ERR, "PCI: Had to wait for device %s.\n",
+						dev_path(dev));
+		}
+
+		/*
    	 * If the device does not have a PCI ID disable it. Possibly
    	 * this is because we have already disabled the device. But
    	 * this also handles optional devices that may not always