[PATCH v1 1/1] x86/PCI: Disable e820 usage for the resource allocation

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

The resource management improve for PCI on x86 broke booting of Intel MID
platforms. It seems that the current code removes all available resources
from the list and none of the PCI device may be initialized. Restore the
old behaviour by force disabling the e820 usage for the resource allocation.

Fixes: 4c5e242d3e93 ("x86/PCI: Clip only host bridge windows for E820 regions")
Depends-on: fa6dae5d8208 ("x86/PCI: Add kernel cmdline options to use/ignore E820 reserved regions")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 arch/x86/include/asm/pci_x86.h | 1 +
 arch/x86/pci/acpi.c            | 2 +-
 arch/x86/pci/intel_mid_pci.c   | 1 +
 3 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index f52a886d35cf..503f83fbc686 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -126,6 +126,7 @@ extern const struct pci_raw_ops *raw_pci_ext_ops;
 extern const struct pci_raw_ops pci_mmcfg;
 extern const struct pci_raw_ops pci_direct_conf1;
 extern bool port_cf9_safe;
+extern bool pci_use_e820;
 
 /* arch_initcall level */
 #ifdef CONFIG_PCI_DIRECT
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index a4f43054bc79..ac2f220d50fc 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -20,7 +20,7 @@ struct pci_root_info {
 #endif
 };
 
-static bool pci_use_e820 = true;
+bool pci_use_e820 = true;
 static bool pci_use_crs = true;
 static bool pci_ignore_seg;
 
diff --git a/arch/x86/pci/intel_mid_pci.c b/arch/x86/pci/intel_mid_pci.c
index 8edd62206604..7869b86bff04 100644
--- a/arch/x86/pci/intel_mid_pci.c
+++ b/arch/x86/pci/intel_mid_pci.c
@@ -313,6 +313,7 @@ int __init intel_mid_pci_init(void)
 	pcibios_enable_irq = intel_mid_pci_irq_enable;
 	pcibios_disable_irq = intel_mid_pci_irq_disable;
 	pci_root_ops = intel_mid_pci_ops;
+	pci_use_e820 = false;
 	pci_soc_mode = 1;
 	/* Continue with standard init */
 	acpi_noirq_set();
-- 
2.35.1