[patch v11 07/23] ARM64 / ACPI: Introduce PCI stub functions for ACPI

Hanjun Guo hanjun.guo at linaro.org
Tue Mar 24 07:02:40 PDT 2015

CONFIG_ACPI depends CONFIG_PCI on x86 and ia64, in ARM64 server
world we will have PCIe in most cases, but some of them may not,
make CONFIG_ACPI depend CONFIG_PCI on ARM64 will satisfy both.

With that case, we need some arch dependent PCI functions to
access the config space before the PCI root bridge is created, and
pci_acpi_scan_root() to create the PCI root bus. So introduce
some stub function here to make ACPI core compile and revisit
them later when implemented on ARM64.

CC: Liviu Dudau <Liviu.Dudau at arm.com>
CC: Catalin Marinas <catalin.marinas at arm.com>
CC: Will Deacon <will.deacon at arm.com>
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit at amd.com>
Tested-by: Yijing Wang <wangyijing at huawei.com>
Tested-by: Mark Langsdorf <mlangsdo at redhat.com>
Tested-by: Jon Masters <jcm at redhat.com>
Tested-by: Timur Tabi <timur at codeaurora.org>
Tested-by: Robert Richter <rrichter at cavium.com>
Acked-by: Robert Richter <rrichter at cavium.com>
Reviewed-by: Grant Likely <grant.likely at linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo at linaro.org>
 arch/arm64/include/asm/pci.h |  6 ++++++
 arch/arm64/kernel/pci.c      | 25 +++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/arch/arm64/include/asm/pci.h b/arch/arm64/include/asm/pci.h
index 872ba93..b008a72 100644
--- a/arch/arm64/include/asm/pci.h
+++ b/arch/arm64/include/asm/pci.h
@@ -27,6 +27,12 @@
 extern int isa_dma_bridge_buggy;
 #ifdef CONFIG_PCI
+static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
+	/* no legacy IRQ on arm64 */
+	return -ENODEV;
 static inline int pci_proc_domain(struct pci_bus *bus)
 	return 1;
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 6f93c24..4095379 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -10,6 +10,7 @@
+#include <linux/acpi.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
@@ -46,3 +47,27 @@ int pcibios_add_device(struct pci_dev *dev)
 	return 0;
+ * raw_pci_read/write - Platform-specific PCI config space access.
+ */
+int raw_pci_read(unsigned int domain, unsigned int bus,
+		  unsigned int devfn, int reg, int len, u32 *val)
+	return -ENXIO;
+int raw_pci_write(unsigned int domain, unsigned int bus,
+		unsigned int devfn, int reg, int len, u32 val)
+	return -ENXIO;
+/* Root bridge scanning */
+struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
+	/* TODO: Should be revisited when implementing PCI on ACPI */
+	return NULL;

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