soc/intel: Fix regression with hidden PCI devices

Fix regression with commit
  903b40a soc/intel: Replace uses of dev_find_slot()

Platforms where FSP hides PCI devices before enumeration
may halt with error message 'PCI: dev is NULL!'.

The workaround here is to print an error message revealing
the faulty source code function and revert to old behaviour
of dev_find_slot().

Change-Id: I5eab3e7f1993b686103eaa257aacda379dc259fa
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34285
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-by: Maxim Polyakov <max.senia.poliak@gmail.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Christian Walter <christian.walter@9elements.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

8 files changed, 29 insertions, 15 deletions

diff --git a/src/device/device_const.c b/src/device/device_const.c
index c1b0b063ff..f2f0177f57 100644
--- a/src/device/device_const.c
+++ b/src/device/device_const.c
@@ -234,6 +234,18 @@ DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn)
 	return pcidev_path_on_root(PCI_DEVFN(dev, fn));
 }
 
+DEVTREE_CONST struct device *pcidev_path_on_root_debug(pci_devfn_t devfn, const char *func)
+{
+	DEVTREE_CONST struct device *dev = pcidev_path_on_root(devfn);
+	if (dev)
+		return dev;
+
+	printk(BIOS_ERR, "BUG: %s requests hidden 00:%02x.%u\n", func, devfn >> 3, devfn & 7);
+
+	/* FIXME: This can return wrong device. */
+	return dev_find_slot(0, devfn);
+}
+
 /**
  * Given an SMBus bus and a device number, find the device structure.
  *
diff --git a/src/include/device/device.h b/src/include/device/device.h
index 676da65263..d6f80cee0f 100644
--- a/src/include/device/device.h
+++ b/src/include/device/device.h
@@ -275,8 +275,6 @@ void mmconf_resource(struct device *dev, unsigned long index);
 void tolm_test(void *gp, struct device *dev, struct resource *new);
 u32 find_pci_tolm(struct bus *bus);
 
-DEVTREE_CONST struct device *dev_find_slot(unsigned int bus,
-						unsigned int devfn);
 DEVTREE_CONST struct device *dev_find_next_pci_device(
 				DEVTREE_CONST struct device *previous_dev);
 DEVTREE_CONST struct device *dev_find_slot_on_smbus(unsigned int bus,
@@ -292,6 +290,10 @@ DEVTREE_CONST struct device *pcidev_path_on_bus(unsigned int bus, pci_devfn_t de
 DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn);
 DEVTREE_CONST struct bus *pci_root_bus(void);
 
+/* To be deprecated, avoid using. */
+DEVTREE_CONST struct device *dev_find_slot(unsigned int bus, unsigned int devfn);
+DEVTREE_CONST struct device *pcidev_path_on_root_debug(pci_devfn_t devfn, const char *func);
+
 void scan_smbus(struct device *bus);
 void scan_generic_bus(struct device *bus);
 void scan_static_bus(struct device *bus);
diff --git a/src/soc/intel/apollolake/include/soc/pci_devs.h b/src/soc/intel/apollolake/include/soc/pci_devs.h
index a334f63468..c5eaf4c3e8 100644
--- a/src/soc/intel/apollolake/include/soc/pci_devs.h
+++ b/src/soc/intel/apollolake/include/soc/pci_devs.h
@@ -22,8 +22,8 @@
 
 #if !defined(__SIMPLE_DEVICE__)
 #include <device/device.h>
-#define _SA_DEV(slot)		pcidev_path_on_root(_SA_DEVFN(slot))
-#define _PCH_DEV(slot, func)	pcidev_path_on_root(_PCH_DEVFN(slot, func))
+#define _SA_DEV(slot)		pcidev_path_on_root_debug(_SA_DEVFN(slot), __func__)
+#define _PCH_DEV(slot, func)	pcidev_path_on_root_debug(_PCH_DEVFN(slot, func), __func__)
 #else
 #define _SA_DEV(slot)		PCI_DEV(0, SA_DEV_SLOT_ ## slot, 0)
 #define _PCH_DEV(slot, func)	PCI_DEV(0, PCH_DEV_SLOT_ ## slot, func)
diff --git a/src/soc/intel/broadwell/include/soc/pci_devs.h b/src/soc/intel/broadwell/include/soc/pci_devs.h
index 522e3eb166..ae3e08f661 100644
--- a/src/soc/intel/broadwell/include/soc/pci_devs.h
+++ b/src/soc/intel/broadwell/include/soc/pci_devs.h
@@ -25,8 +25,8 @@
 #else
 #include <device/device.h>
 #include <device/pci_def.h>
-#define _SA_DEV(slot)		pcidev_path_on_root(_SA_DEVFN(slot))
-#define _PCH_DEV(slot, func)	pcidev_path_on_root(_PCH_DEVFN(slot, func))
+#define _SA_DEV(slot)		pcidev_path_on_root_debug(_SA_DEVFN(slot), __func__)
+#define _PCH_DEV(slot, func)	pcidev_path_on_root_debug(_PCH_DEVFN(slot, func), __func__)
 #endif
 
 /* System Agent Devices */
diff --git a/src/soc/intel/cannonlake/include/soc/pci_devs.h b/src/soc/intel/cannonlake/include/soc/pci_devs.h
index 1bc028f194..33814b0330 100644
--- a/src/soc/intel/cannonlake/include/soc/pci_devs.h
+++ b/src/soc/intel/cannonlake/include/soc/pci_devs.h
@@ -24,8 +24,8 @@
 
 #if !defined(__SIMPLE_DEVICE__)
 #include <device/device.h>
-#define _SA_DEV(slot)		pcidev_path_on_root(_SA_DEVFN(slot))
-#define _PCH_DEV(slot, func)	pcidev_path_on_root(_PCH_DEVFN(slot, func))
+#define _SA_DEV(slot)		pcidev_path_on_root_debug(_SA_DEVFN(slot), __func__)
+#define _PCH_DEV(slot, func)	pcidev_path_on_root_debug(_PCH_DEVFN(slot, func), __func__)
 #else
 #define _SA_DEV(slot)		PCI_DEV(0, SA_DEV_SLOT_ ## slot, 0)
 #define _PCH_DEV(slot, func)	PCI_DEV(0, PCH_DEV_SLOT_ ## slot, func)
diff --git a/src/soc/intel/denverton_ns/include/soc/pci_devs.h b/src/soc/intel/denverton_ns/include/soc/pci_devs.h
index 303ba67e65..27f9e35326 100644
--- a/src/soc/intel/denverton_ns/include/soc/pci_devs.h
+++ b/src/soc/intel/denverton_ns/include/soc/pci_devs.h
@@ -27,8 +27,8 @@
 #if ENV_RAMSTAGE
 #include <device/device.h>
 #include <device/pci_def.h>
-#define _SA_DEV(slot) pcidev_path_on_root(_SA_DEVFN(slot))
-#define _PCH_DEV(slot, func) pcidev_path_on_root(_PCH_DEVFN(slot, func))
+#define _SA_DEV(slot) pcidev_path_on_root_debug(_SA_DEVFN(slot), __func__)
+#define _PCH_DEV(slot, func) pcidev_path_on_root_debug(_PCH_DEVFN(slot, func), __func__)
 #else
 #define _SA_DEV(slot) PCI_DEV(0, SA_DEV_SLOT_##slot, 0)
 #define _PCH_DEV(slot, func) PCI_DEV(0, PCH_DEV_SLOT_##slot, func)
diff --git a/src/soc/intel/icelake/include/soc/pci_devs.h b/src/soc/intel/icelake/include/soc/pci_devs.h
index 1348f23b78..0eddee2790 100644
--- a/src/soc/intel/icelake/include/soc/pci_devs.h
+++ b/src/soc/intel/icelake/include/soc/pci_devs.h
@@ -23,8 +23,8 @@
 
 #if !defined(__SIMPLE_DEVICE__)
 #include <device/device.h>
-#define _SA_DEV(slot)		pcidev_path_on_root(_SA_DEVFN(slot))
-#define _PCH_DEV(slot, func)	pcidev_path_on_root(_PCH_DEVFN(slot, func))
+#define _SA_DEV(slot)		pcidev_path_on_root_debug(_SA_DEVFN(slot), __func__)
+#define _PCH_DEV(slot, func)	pcidev_path_on_root_debug(_PCH_DEVFN(slot, func), __func__)
 #else
 #define _SA_DEV(slot)		PCI_DEV(0, SA_DEV_SLOT_ ## slot, 0)
 #define _PCH_DEV(slot, func)	PCI_DEV(0, PCH_DEV_SLOT_ ## slot, func)
diff --git a/src/soc/intel/skylake/include/soc/pci_devs.h b/src/soc/intel/skylake/include/soc/pci_devs.h
index 5acaaebc5a..0669ced18c 100644
--- a/src/soc/intel/skylake/include/soc/pci_devs.h
+++ b/src/soc/intel/skylake/include/soc/pci_devs.h
@@ -24,8 +24,8 @@
 
 #if !defined(__SIMPLE_DEVICE__)
 #include <device/device.h>
-#define _SA_DEV(slot)		pcidev_path_on_root(_SA_DEVFN(slot))
-#define _PCH_DEV(slot, func)	pcidev_path_on_root(_PCH_DEVFN(slot, func))
+#define _SA_DEV(slot)		pcidev_path_on_root_debug(_SA_DEVFN(slot), __func__)
+#define _PCH_DEV(slot, func)	pcidev_path_on_root_debug(_PCH_DEVFN(slot, func), __func__)
 #else
 #define _SA_DEV(slot)		PCI_DEV(0, SA_DEV_SLOT_ ## slot, 0)
 #define _PCH_DEV(slot, func)	PCI_DEV(0, PCH_DEV_SLOT_ ## slot, func)
@@ -39,7 +39,7 @@
 
 #define SA_DEV_SLOT_PEG		0x01
 #define  SA_DEVFN_PEG(func)	PCI_DEVFN(SA_DEV_SLOT_PEG, func)
-#define  SA_DEV_PEG(func)	pcidev_path_on_root(SA_DEVFN_PEG(func))
+#define  SA_DEV_PEG(func)	pcidev_path_on_root_debug(SA_DEVFN_PEG(func), __func__)
 #define  SA_DEV_PEG0		SA_DEV_PEG(0)
 #define  SA_DEV_PEG1		SA_DEV_PEG(1)
 #define  SA_DEV_PEG2		SA_DEV_PEG(2)