[linux] Add support for accessing PCI configuration space via /proc/bus/pci

Signed-off-by: Michael Brown <mcb30@ipxe.org>

4 files changed, 140 insertions, 0 deletions

diff --git a/src/include/ipxe/errfile.h b/src/include/ipxe/errfile.h
index 67edcc931..2b9d16ca0 100644
--- a/src/include/ipxe/errfile.h
+++ b/src/include/ipxe/errfile.h
@@ -275,6 +275,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #define ERRFILE_efi_init	      ( ERRFILE_OTHER | 0x00390000 )
 #define ERRFILE_efi_timer	      ( ERRFILE_OTHER | 0x003a0000 )
 #define ERRFILE_efi_umalloc	      ( ERRFILE_OTHER | 0x003b0000 )
+#define ERRFILE_linux_pci	      ( ERRFILE_OTHER | 0x003c0000 )
 
 /** @} */
 
diff --git a/src/include/ipxe/linux.h b/src/include/ipxe/linux.h
index dac508ea6..a01ace3de 100644
--- a/src/include/ipxe/linux.h
+++ b/src/include/ipxe/linux.h
@@ -30,6 +30,14 @@ FILE_LICENCE(GPL2_OR_LATER);
 #include <ipxe/device.h>
 #include <ipxe/settings.h>
 
+/**
+ * Convert a Linux error number to an iPXE status code
+ *
+ * @v errno		Linux error number
+ * @ret rc		iPXE status code (before negation)
+ */
+#define ELINUX( errno ) EPLATFORM ( EINFO_EPLATFORM, errno )
+
 /** A linux device */
 struct linux_device {
 	/** Generic device */
diff --git a/src/include/ipxe/linux/linux_pci.h b/src/include/ipxe/linux/linux_pci.h
new file mode 100644
index 000000000..439166733
--- /dev/null
+++ b/src/include/ipxe/linux/linux_pci.h
@@ -0,0 +1,130 @@
+#ifndef _IPXE_LINUX_PCI_H
+#define _IPXE_LINUX_PCI_H
+
+/** @file
+ *
+ * iPXE PCI API for Linux
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#ifdef PCIAPI_LINUX
+#define PCIAPI_PREFIX_linux
+#else
+#define PCIAPI_PREFIX_linux __linux_
+#endif
+
+struct pci_device;
+
+extern int linux_pci_read ( struct pci_device *pci, unsigned long where,
+			    unsigned long *value, size_t len );
+extern int linux_pci_write ( struct pci_device *pci, unsigned long where,
+			     unsigned long value, size_t len );
+
+/**
+ * Read byte from PCI configuration space
+ *
+ * @v pci	PCI device
+ * @v where	Location within PCI configuration space
+ * @v value	Value read
+ * @ret rc	Return status code
+ */
+static inline __always_inline int
+PCIAPI_INLINE ( linux, pci_read_config_byte ) ( struct pci_device *pci,
+						unsigned int where,
+						uint8_t *value ) {
+	int rc;
+	unsigned long tmp;
+
+	rc = linux_pci_read ( pci, where, &tmp, sizeof ( *value ) );
+	*value = tmp;
+	return rc;
+}
+
+/**
+ * Read word from PCI configuration space
+ *
+ * @v pci	PCI device
+ * @v where	Location within PCI configuration space
+ * @v value	Value read
+ * @ret rc	Return status code
+ */
+static inline __always_inline int
+PCIAPI_INLINE ( linux, pci_read_config_word ) ( struct pci_device *pci,
+						unsigned int where,
+						uint16_t *value ) {
+	int rc;
+	unsigned long tmp;
+
+	rc = linux_pci_read ( pci, where, &tmp, sizeof ( *value ) );
+	*value = tmp;
+	return rc;
+}
+
+/**
+ * Read dword from PCI configuration space
+ *
+ * @v pci	PCI device
+ * @v where	Location within PCI configuration space
+ * @v value	Value read
+ * @ret rc	Return status code
+ */
+static inline __always_inline int
+PCIAPI_INLINE ( linux, pci_read_config_dword ) ( struct pci_device *pci,
+						 unsigned int where,
+						 uint32_t *value ) {
+	int rc;
+	unsigned long tmp;
+
+	rc = linux_pci_read ( pci, where, &tmp, sizeof ( *value ) );
+	*value = tmp;
+	return rc;
+}
+
+/**
+ * Write byte to PCI configuration space
+ *
+ * @v pci	PCI device
+ * @v where	Location within PCI configuration space
+ * @v value	Value to be written
+ * @ret rc	Return status code
+ */
+static inline __always_inline int
+PCIAPI_INLINE ( linux, pci_write_config_byte ) ( struct pci_device *pci,
+						 unsigned int where,
+						 uint8_t value ) {
+	return linux_pci_write ( pci, where, value, sizeof ( value ) );
+}
+
+/**
+ * Write word to PCI configuration space
+ *
+ * @v pci	PCI device
+ * @v where	Location within PCI configuration space
+ * @v value	Value to be written
+ * @ret rc	Return status code
+ */
+static inline __always_inline int
+PCIAPI_INLINE ( linux, pci_write_config_word ) ( struct pci_device *pci,
+						 unsigned int where,
+						 uint16_t value ) {
+	return linux_pci_write ( pci, where, value, sizeof ( value ) );
+}
+
+/**
+ * Write dword to PCI configuration space
+ *
+ * @v pci	PCI device
+ * @v where	Location within PCI configuration space
+ * @v value	Value to be written
+ * @ret rc	Return status code
+ */
+static inline __always_inline int
+PCIAPI_INLINE ( linux, pci_write_config_dword ) ( struct pci_device *pci,
+						  unsigned int where,
+						  uint32_t value ) {
+	return linux_pci_write ( pci, where, value, sizeof ( value ) );
+}
+
+#endif /* _IPXE_LINUX_PCI_H */
diff --git a/src/include/ipxe/pci_io.h b/src/include/ipxe/pci_io.h
index 7368cf48b..781b77fe1 100644
--- a/src/include/ipxe/pci_io.h
+++ b/src/include/ipxe/pci_io.h
@@ -44,6 +44,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 
 /* Include all architecture-independent I/O API headers */
 #include <ipxe/efi/efi_pci_api.h>
+#include <ipxe/linux/linux_pci.h>
 
 /* Include all architecture-dependent I/O API headers */
 #include <bits/pci_io.h>